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Wiltshire, Carolyn. "Molecular screens for the isolation of genes involved in Candida albicans morphogenesis." Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU536131.
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Using two related dominant negative screens, galactose-negative cDNAs were isolated that contained C. albicans TUB2 (beta-tubulin), NHP6 (non-histone protein 6), CIT2 (citrate synthase) and MRPS9 (mitochondrial ribosomal protein S9) sequences. CaTUB2 encodes beta-tubulin, a component of the microtubule system of the cytoskeleton. Overexpression of this sequence in S. cerevisiae resulted in lethality associated with cell shape changes characteristics of an arrest in the G2/M phase of the cell division cycle. However, overexpression of an ADH1-CaTUB2 fusion in C. albicans did not affect cell shape. CaNHP6 encodes a protein that shows a high level of sequence identity to ScNhp6A and ScNhp6B, and is closely related to High Mobility Group proteins from other eukaryotes. CaNHP6 overexpression in S. cerevisiae cells caused cell cycle arrest. Expression of an ADH1-CaNHP6 fusion in C. albicans did not affect growth rate, but affected both of cell and colony morphogenesis. These effects were not dependent upon the PKC pathway. CaMRPS9 encodes a protein of the small mitochondrial ribosome subunit, and overexpression of this protein caused the slow development of galactose lethality in S. cerevisiae. The development of lethality correlated with the emergence of petite mutants, indicating that the overexpression of CaMRPS9 interferes with S. cerevisiae mitochondrial function, thereby preventing growth on galactose. Similarly, CaCIT2 expression was presumed to block growth of S. cerevisiae on galactose by interfering with respiratory metabolism. Separate approaches were taken to isolate CaGCN4. This gene was of interest because (a) hypha-specific promoters contain GCRE-like sequences [Gcn4 Response Element], (b) amino acid starvation promotes yeast-to-hypha morphogenesis, and (c) GCN-like responses are thought to occur in C. albicans. The 5'-truncated C. albicans GCN4 cDNA was isolated by functional complementation of a S. cerevisiae Delta gcn4 mutation. The 5'-region of the CaGCN4 ORF, including 624 bp of 5'-untranslated region, was isolated by PCR. The sequences of the overlapping 5' and 3'fragments revealed a major ORF capable of encoding a 323 aa protein with significant homology in its C-terminal bZIP domain to ScGcn4 and other fungal Gcn4-like proteins. The existence of this ORF in the C. albicans genome was confirmed by PCR. The CaGCN4 cDNA contained two upstream ORFs and was encoded by a single exon. The contribution of C. albicans Gcn4 to yeast-to-hypa morphogenesis remains to be verified.
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Woolfson, Adrian. "Natural and artificial forms of human CD1 genes." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282946.
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Syed, Nelofer. "Development of systems to conditionally silence genes in the immune system of the mouse." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406646.
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Alvarez, Contreras Carlos Alberto. "HOST-MICROBIOME INTERACTIONS AND REGULATION OF THE IMMUNE SYSTEM." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1600446008947681.
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Pereira, Lucas Campana. "Busca de genes associados à resposta ao teste de Montenegro para antígenos de Leishmania." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/42/42135/tde-27022013-155152/.
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O presente trabalho visa, através de métodos genético-epidemiológicos, identificarem genes associados à resposta ao antígeno da Leishmania. Utilizando amostras através do teste de Montenegro dos municípios de Monte Negro (RO) e Assis Brasil (AC). Na primeira abordagem foram feitos testes com TaqManÒ e a segunda com GWAS, e análises de associação foram feitas utilizando-se o pacote SPSS e o Plink. Não foram encontradas associações com cinco SNPs (MYD88, IL12, IL10, IFNGR1 e NRAMP1). A análise de dados de varredura genômica com filtros, indicou uma região no cromossomo 10 com 3 SNPs próximos que fazem parte de uma região regulatória que com o posterior auxilio do real time não se confirmaram, apesar do ensaio RS11251056 apresentar valores limítrofes, se tornando uma possível indicação para trabalhos futuros e por fim a último teste foi a meta-análise, através do método de Woolf, apresentou resultados indicativos de associação para ensaios encontrados no cromossomo 2 com ZNF638 relacionados a diferenciação celular e também no cromossomo 10 que contem lincRNAs e o gene NGR3, com dois ensaios apresentando valores significativos de p, onde podemos inferir que estas duas regiões podem participar ativamente na diferenciação da resposta ao antígeno da Leishmania.The present study aims, through genetic-epidemiological methods, to identify genes associated with response to Leishmania antigen. Using samples Montenegro skin test through the municipalities of Monte Negro (RO) and Assis Brazil (AC). In the first approach were tested with TaqManÒ and the second GWAS, and association analyzes were performed using SPSS and Plink. No associations were found with five SNPs (MyD88, IL12, IL10, IFNGR1, and NRAMP1). The analysis of genome scan data with filters, indicated a region on chromosome 10 with three nearby SNPs that are part of a regulatory region that later with the help of real time is not confirmed, although the test rs11251056 have borderline values, becoming an possible direction for future work and finally the last test was the meta-analysis by the method of Woolf, presented results indicating the association found in tests for chromosome 2 with ZNF638 related to cell differentiation and also on chromosome 10 that contains lincRNAs and gene NGR3, two runs with a significant p value, where we can infer that these two regions can actively participate in the differentiation of the response to Leishmania antigen.
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Watherston, Oliver Gavin. "The effect of small DNA tumour virus oncoprotiens on the expression of genes involved in the immune system." Thesis, University of Leeds, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.535132.
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Lo, Amanda Susana. "Role of Genes in the Jak-Stat Pathway in the Innate Immune System and Immunosenescence in Drosophila melanogaster." Thesis, University of Maryland, Baltimore County, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10275514.
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For many organisms, the immune system tends to deteriorate with age, leading to higher susceptibility to foreign pathogens. While several biological pathways are associated with immunity, the components of the Janus-kinase-Signal Transducers and Activators of Transcription (JAK-STAT) pathway on immunity at different age groups is unclear. This study explored the knock down effects of the Drosophila JAK-STAT pathway components and a candidate gene, robo3, in blood cells. Assessments of immune function were conducted through bacterial clearance assays and phagocytosis assay at one-week and five-weeks of age. This study suggests that some JAK-STAT pathway components important in other cell types seem to have less of a role in blood cells and immunity.
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Baú, Carlos Eduardo Giuliani. "IDENTIFICAÇÃO DE GENES DIFERENCIALMENTE EXPRESSOS EM GLIOBLASTOMA E SUA RELAÇÃO NAS VIAS DO SISTEMA IMUNOLÓGICO Santa Maria, RS 2016." Centro Universitário Franciscano, 2016. http://www.tede.universidadefranciscana.edu.br:8080/handle/UFN-BDTD/546.
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Microarrays are instruments for measurement and analysis of several genes simultaneously, one of its uses is the verification of distinguishing gene expression in diseases. This work aims to verify the distinction between the expression of proteins in glioblastoma, using the data collected from the Gene Expression Omnibus database, because this cancer is characterized as of high incidence and it’s difficult to treat. After computational statistical analysis, it was found that the genes TNIP2, TOLLIP, IKBKB, PSMF1, RASGRF2, NEFL, DNM1, CDC42, YES1, C1S and PAK1, are differentially expressed in the pathways of the immune system, however, only the genes TNIP2, TOLLIP, IKBKB, are part of the NF-KB pathway, known to fight inflammation. The expectation of this work, and it´s future studies, hope to demonstrate different expressed genes in the immune system and thus help to better understand the development of the disease and its treatment, by nanoencapsulation of temozolimoda, a drug used along with radiotherapy.
Microarranjos são instrumentos para leituras e análise de vários genes simultaneamente, sendo uma de suas utilizações a verificação da distinção de expressão de genes em doenças. A partir disso, este trabalho busca verificar a distinção de expressão entre as proteínas de glioblastoma, por meio de dados recolhidos do banco de dados Gene Expression Omnibus, por caracterizar-se como um câncer de grande incidência e difícil tratamento. Na análise estatística computacional realizada, constatou-se que os genes TNIP2, TOLLIP, IKBKB, PSMF1, RASGRF2, NEFL, DNM1, CDC42, YES1, C1S e PAK1, encontram-se diferencialmente expressos nas vias do sistema imunológico, porém, somente os genes TNIP2, TOLLIP, IKBKB, fazem parte da via NF-KB, conhecida no combate à inflamação. Espera-se com esse trabalho, além de aprimorá-lo em estudos futuros, complementar os estudos nesta área, pois sua análise poderá demonstrar diferentes genes expressos nas vias do sistema imunológico, podendo, assim, auxiliar na melhor compreensão no desenvolvimento da doença, bem como, seu tratamento, por meio da nanoencapsulação do temozolimoda, medicamento utilizado juntamente com radioterapia.
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Silva, Cláudia Regina dos Santos. "Análise da expressão de genes envolvidos na resposta inflamatória em crianças com síndrome de Down." Faculdade de Medicina de São José do Rio Preto, 2015. http://hdl.handle.net/tede/286.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
ABSTRACT Introduction: Down syndrome (DS) is a genetic disorder caused by the presence of an extra copy of human chromosome 21 (HSA21) with an incidence of one in 660 live births. Individuals with DS show alterations of the immune system resulting in increased frequency of infections and autoimmune diseases. Studies show that some genes involved in the immune system present altered expression in individuals with DS, however, the molecular mechanisms by which trisomy 21 leads to the immune system disorders in DS remain poorly investigated. Objective: This study aimed to investigate the expression pattern of a specific set of genes involved in the immune system and inflammation process in children with DS and children without the syndrome (control group), to identify differences that may be related to clinical manifestations of the syndrome. Casuistic and Methods: In this study were included six children with DS and six children without the syndrome. The quantification of the gene expression was performed using TaqMan ® Array Plate Human Inflammation Kit, which enables the investigation of 92 inflammation-related genes and four reference genes by real-time polymerase chain reaction (qPCR). Results: Of the 92 genes analyzed, 20 genes showed differential expression in children DS; 12 overexpressed (PLA2G2D, CACNA1D, ALOX12, VCAM1, ICAM1, PLCD1, ADRB1, HTR3A, PDE4C, CASP1, PLA2G5 e PLCB4) and 8 underexpressed (LTA4H, BDKRB1, ADRB2, CD40LG, ITGAM, TNFRSF1B, ITGB1 e TBXAS1). After statistical correction for false discovery rate, only the genes BDKRB1 and LTA4H showed differential expression, both underexpressed. Conclusion: DS children show differential expression of genes, not located on chromosome 21, compared to children without DS. The altered expression of these genes, considering their functions in the inflammatory response, suggests an important role in DS pathogenesis.
RESUMO Introdução: A síndrome de Down (SD) é um distúrbio genético causado pela presença de uma cópia extra do cromossomo humano 21 (HSA 21) com uma incidência de um a cada 660 nascidos vivos. Indivíduos com SD apresentam alterações no sistema imunológico que resultam no aumento da frequência de infecções e doenças autoimunes. Estudos mostram que alguns genes envolvidos no sistema imunológico apresentam expressão alterada em indivíduos com SD, entretanto, os mecanismos moleculares pelos quais a trissomia do 21 leva aos distúrbios do sistema imunológico em SD permanecem pouco investigados. Objetivo: O presente trabalho teve como objetivo investigar o padrão de expressão de um conjunto específico de genes envolvidos no sistema imunológico e no processo inflamatório em crianças com SD e crianças sem a síndrome (grupo controle), visando identificar diferenças que possam estar relacionadas com manifestações clínicas da síndrome. Casuística e Métodos: Foram incluídas no estudo seis crianças com SD e seis crianças sem a síndrome. A quantificação da expressão gênica foi realizada com o kit TaqMan® Human Plate Inflammation Array, que permite a investigação de 92 genes relacionados com a inflamação e quatro genes de referência pelo método de reação em cadeia da polimerase quantitativa em tempo real (PCRq). Resultados: Dos 92 genes analisados, 20 genes apresentaram expressão diferencial em crianças com SD; 12 com expressão aumentada (PLA2G2D, CACNA1D, ALOX12, VCAM1, ICAM1, PLCD1, ADRB1, HTR3A, PDE4C, CASP1, PLA2G5 e PLCB4) e oito com expressão reduzida (LTA4H, BDKRB1, ADRB2, CD40LG, ITGAM, TNFRSF1B, ITGB1 e TBXAS1). Após correção estatística para múltiplos testes apenas os genes BDKRB1 e LTA4H apresentaram expressão diferencial, ambos com expressão reduzida. Conclusão: Crianças com SD apresentam expressão diferencial de genes, não localizados no cromossomo 21, em relação a crianças sem a síndrome. A expressão alterada desses genes, considerando suas funções na resposta inflamatória, sugere um papel relevante na patogênese da SD.
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Shater, A. F. "Investigation of DNA variation in genes of the immune system in wild populations of Apodemus sylvaticus in relation to infection by Toxoplasma gondii and helminth parasites." Thesis, University of Salford, 2017. http://usir.salford.ac.uk/44600/.
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The aims of this study are to investigate DNA sequence variation in immune genes from Apodemus sylvaticus in relation to parasite infection. The purpose is to investigate the hypothesis that immune gene variation can influence parasite infection. Evidence from other studies, such as infection of wild voles with Borrelia and cattle with bovine tuberculosis, has demonstrated that the DNA sequence (and therefore the protein sequence) of toll-like receptors (TLRs) is correlated with infection status. Recent laboratory studies on mice showed that the genes for TLR11 or TLR12 are essential for recognition of the parasite Toxoplasma gondii. Furthermore, the NLRP1b gene, a key component in regulating inflammation during infection, her been found in laboratory studies to be responsible for resistance of the mice against toxoplasmosis. Also, it is located at the Toxo1 locus which has been shown to be a key host locus for controlling Toxoplasma parasite proliferation and recent studies on inbred mice confirm that NLRP1b is the main gene that is responsible for this control. But little is known of the role of these innate immune system genes in natural populations. The purpose of this study is to investigate gene diversity in relation to parasite infection in wild rodent populations. A recent study in our laboratory resulted in 126 wild wood mice (Apodemus sylvaticus) being tested for T. gondii infection and other helminth parasites. This provides a topical opportunity to investigate DNA polymorphisms in NLRP1 and TLRs that could be associated with infection. In a study which investigated polymorphisms in relation to TLR11 and TLR 12, several relations were obtained but only one of them is significant which is the relationship between Syphacea infection with H2 and non H2 haplotype. At the start of the project no sequence was available for the NLRP1b gene from A. sylvaticus. Using Clustal alignment of DNA sequences from Mus musculus and other rodents, several combinations of PCR primer pairs were designed and tested for the amplification of parts of this gene from A. sylvaticus. The amplification is complex due to the arrangement of exons and introns, but successful sequences have been obtained for Exon 3 part 2 and Exon 3 part 3 (approximately 450 base pairs) which covers the function region, called NACHT, from 80 mice. Polymorphisms were found at amino acid positions 15 and 22 of exon 3-2 and positions 11 and 36 of exon 3-3. Exon 3-2 amino acid polymorphism is either methionine or leucine at position 15 and glutamic acid or alanine at position 22. Exon 3-3 amino acid polymorphism is either histidine or leucine at position 16 and glutamic acid or lysine at position 36. The polymorphisms found in the NLRP1b gene were examined for any relationship to a broad range of nematode parasites. One of the exon 3-2 haplotypes (H1/H2) shows a significant association with different nematodes and two haplotypes (H2/H3 and H4/H4) have a significant association with Toxoplasma gondii in respect for different helminth parasites. Furthermore, three of the exon 3-3 haplotypes (H1/H4, H4/H4 and H3/H3) show a significant association with different nematodes and one haplotype (H4/H4) has a significant association with Toxoplasma gondii. In addition, one haplotype of exon 3-3 which is H2/H2 showed a significant association with parasitic infection status (negative or multiple parasites). Also, the homozygosity and heterozygosity of the SNPs were investigated. For exon 3-2, the homozygosity of the first SNPs locus showed significant association with Toxoplasma gondii. For exon 3-3, the homozygosity of the first SNPs locus, and the second SNPs locus when analysed separately show significant association with Toxoplasma gondii. But, when analysed together, the heterozygosity of both SNPs locus showed significant association with Toxoplasma gondii in respect for different helminth parasites. In this study, DNA sequence variation was found in the immune genes (TLR11, 12 and NLRP1b) natural populations of wood mice. There was an association between some haplotypes and parasite infection. This provides evidence in support of the hypothesis that variation in immune gene sequences can influence parasite infection. Future studies should be aimed at identifying the detailed interactions between parasites and host immune genes in natural populations of wild animals.
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Bilal, R. "Dynamics of gene regulatory networks in the immune system." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1386220/.
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The aim of this project is to study the dynamics of Gene Regulatory Networks (GRN) in the immune system. For this purpose two principles of regulation were discussed. First principle is to study the effect of the speed with which the system crosses the critical region on choosing the final attractor in bistable system and in the immune system genetic switch that governs the differentiation of progenitor cell in the presence of small asymmetries and fluctuations. Second is to study the constructive role played by high-frequency force driving vibrational resonance (VR), and the effect of interaction between vibrational resonance and stochastic resonance in signal detection. Understanding the integrated behaviour of gene regulatory networks, RNA, proteins and other molecules that mutually interact to control the dynamical behaviour of the network within and between cells, has come out as a fundamental problem in system biology. To study the effect of external signalling speed, we specifically analyzed the role of parameter sweeping, external asymmetry, and noise in the canonical supercritical pitch- fork bifurcation model, both by numerical simulations and analytical solutions. As genetic switch exhibits bistable behaviour in its dynamics, we will apply these results to genetic switch by using model of immune system genetic switch that governs differentiation of progenitor cell into two different fates. Since cell phenotype in stem cell differentiation, cell cycle progression, or apoptosis has been successfully identified as attractors of a whole network. So in the presence of small asymmetries and fluctuations, slow passage through the critical region increases considerably specific attractor selection, which has strong implication for the cell fate decision process. Excitable system do not respond to stimulus that is below its excitation threshold. We studied in detail two phenomena vibrational resonance and stochastic resonance to enhance the response of an excitable system to a low-frequency sub-threshold, by first considering mathematical model of excitable neurons the Fitz-Hugh Nagumo (FHN model), and then applying same phenomena on two different models of excitable genetic circuits. When optimal amplitude of high-frequency signal enhance the response of an excitable system to low-frequency sub-threshold is called vibrational resonance, while when appropriate noise intensities enhance the system detection of sub-threshold signals then this phenomenon is called stochastic resonance. We found for two different biological systems that adding a high-frequency force of an appropriate amplitude to the system enhance the neural or genetic response to a sub-threshold low-frequency signal. Also appropriate Gaussian white noise intensities reduces the optimal response that can be reached by vibrational resonance alone but it also reduce high-frequency amplitude that gives best response.
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Seymour, Rosemarie. "Mutations in the Mouse Sharpin Gene Cause the Chronic Proliferative Dermatitis Phenotype." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/SeymourR2008.pdf.
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Roberts, Amy Louise. "Genetic variation of innate immune receptor genes in Systemic Lupus Erythematosus." Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/genetic-variation-of-innate-immune-receptor-genes-in-systemic-lupus-erythematosus(9f2194d8-f4d5-4fe8-abda-b6712e34404a).html.
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Genetic variations within loci encoding cell surface receptors of the innate immune system, such as Complement Receptor 3 (CR3) and Fc gamma Receptors (FcγRs), are strongly associated with Systemic Lupus Erythematosus (SLE). Such genetic associations implicate the functional importance of these receptors in disease pathogenesis. CR3 (also known as CD18/CD11b) is an integrin receptor found on multiple immune cell types, including monocytes/macrophages, neutrophils, and Natural Killer (NK) cells. CR3 is a promiscuous receptor with many natural ligands, including complement fraction iC3b, ICAM-1, and β-glucan, and functions as a phagocytic receptor, leukocyte adhesion molecule, and immune regulator. ITGAM encodes the α-chain (CD11b) of CR3, and a common polymorphism (rs1143679) within ITGAM, which results in a non-synonymous amino acid substitution (R77H) in CD11b, is robustly associated with SLE (OR=1.76). In this thesis I demonstrate that the SLE-associated R77H common polymorphism does not affect the cell surface expression of CR3 on ex vivo monocytes and neutrophils in a healthy cohort of European ancestry. Additionally, a collaborative resequencing project identified two case-specific non-synonymous coding variants in ITGAM, which I demonstrate result in the under-functioning of CR3-mediated phagocytosis using an in vitro model. Finally, using a CR3-specific small molecule drug, which has therapeutic potential in inflammatory disease, I observed a CR3-dependent significant reduction in STAT5 phosphorylation following NK cell activation with cytokines. There are two genetic variants found within the FCGR locus on chromosome 1 which are robustly associated with SLE; homozygosity of the I232T (rs1050501) polymorphism within FcγRIIb (FCGR2B), and decreased gene copy number of FCGR3B. Recent work demonstrated that a consequence of a deletion at the FCGR locus, spanning the entire FCGR3B gene and parts of the upstream FCGR2C and downstream FCGR2B genes, results in ectopic expression of FcγRIIb on NK cells. In this thesis I explored the possibility of a genetic interaction between the two – copy number variation (FCGR3B) and rs1050501 (FCGR2B) - SLE-associated variants, but failed to detect such an effect within the European cohort used.
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Sotsios, Yannis. "Chemokines and T cells : activation requirements for RANTES secretion and CXCR4 signalling in mature T cells." Thesis, University of Bath, 2000. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323606.
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Cooper, Laken N. "Effects of Sleep Fragmentation on the Immune System of Zebra Finches Using Cytokine Gene Expression." TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1623.
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Sleep loss is known to trigger an inflammatory response and increase serum corticosterone in both human and murine models. However, very little evidence is available on the potential effects of sleep loss in avian models. This study aims to construct a profile using cytokine gene expression data to determine how birds respond to sleep loss in a controlled environment. I investigated changes in pro-inflammatory (IL-1β and IL-6) and anti-inflammatory (IL-10) cytokine gene expression in the periphery (fat, liver, spleen, and heart) and brain (hypothalamus, hippocampus, and apical hyperpallium) in zebra finches exposed to a novel sleep fragmentation method. Serum corticosterone, body mass, and behavioral profiles also were assessed. Sleep was interrupted periodically for over 12 hours using a sleep fragmentation chamber, which was modified from those typically used in murine studies. This chamber contained a sweeping wire bar that moved the distance of the cage at 2-minute intervals. I predicted that sleep fragmented birds would exhibit elevated pro-inflammatory and reduced anti-inflammatory gene expression relative to those birds that were not sleep fragmented. In addition, I predicted a decrease in body mass and an increase in serum corticosterone levels because of sleep fragmentation. Contrary to my predictions, sleep fragmentation resulted in lower levels of IL-1β in the apical hyperpallium, but lower levels of IL- 10 in the hippocampus. No differences were detected in the adipose tissue of individuals exposed to sleep loss. Sleep fragmentation resulted in an increase in percent body mass lost. Serum corticosterone levels did not differ across groups. These data provide preliminary insight into the inflammatory response that is seen as a result of sleep loss in an avian model. Overall, it appears that as compared to some mammals such as murine rodents, birds are not as susceptible to sleep loss.
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Neto, Guilherme Tude Coelho. "Peptídeo antimicrobiano LL-37 e seus efeitos em stemness de diferentes células tumorais." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5164/tde-06032017-104147/.
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Os peptídeos antimicrobianos desempenham papéis protetores críticos em uma gama de doenças humanas, incluindo o câncer. Vários estudos demonstraram funções - tais como proliferação, angiogênese, apoptose e imunomodulação - desses peptídeos em vias cancerígenas cruciais. Investigamos o papel do Peptídeo antimicrobiano LL-37 sobre stemness em câncer de mama (SKBR3) e células de melanoma (A375). Análise por PCR array da expressão diferencial de genes em SKBR3 e A375 com knockdown por siRNA para o mRNA de LL-37 revelou uma regulação negativa de genes relacionados com stemness, incluindo transcriptase reversa da telomerase, forkhead box D3 e para o fator indiferenciado de transcrição de células embrionárias 1, notavelmente em células de câncer de mama.Além disso, as células SKBR3 com knockdown para a expressão de LL-37 mostraram uma diminuição da produção de oncosferas em comparação com controles negativos, enquanto as células A375 exibiram uma produção aumentada. Tomados em conjunto, nossos achados indicam um papel para LL- 37 em stemness, dependendo do tipo de celular analisadoAntimicrobial peptides play critical protective roles in a range of human diseases, including cancer. Multiple studies have demonstrated functions -- such as proliferation, angiogenesis, apoptosis and immunomodulation -- of these peptides in crucial cancer pathways. We investigated the role of the antimicrobial peptide LL-37 on stemness in breast cancer (SKBR3) and melanoma cells (A375). PCR array analysis of differential gene expression in SKBR3 and A375 cancer cell lines downregulated for LL-37 expression by siRNA revealed downregulation of genes related to stemness, including telomerase reverse transcriptase, forkhead box D3 and undifferentiated embryonic cell transcription factor 1, remarkably in breast cancer cells. Furthermore, SKBR3 cells knocked down for LL-37 expression showed a decreased production of oncospheres in comparison with negative controls, while A375 cells exhibited increased production. Taken collectively, our findings indicate a role for LL-37 in cancer cell stemness depending on the cell type
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Bassano, Irene. "Regulation of gene expression in the immune system and in virally-transformed cells." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7724/.
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The correct development and functioning of the immune system is critical for the defence of the host organism against pathogens and cancers. V(D)J recombination generates diversity of immunoglobulin (Ig) and T cell receptor (TCR) genes by the regulated joining of variable (V), diversity (D) and joining (J) gene segments. Tissue-specific enhancers in the DNA genome activate these genes to undergo recombina-tion by triggering non-coding transcription through the recombining gene segments, following interaction with the respective promoters. How this is achieved is un-known. The specificity of enhancer/promoter interactions was examined using the murine Igλ chain locus. The transcription factors that bind to the three main promoters were identified by DNase I footprinting. Of these, a factor termed E47 was shown to interact with IRF4 by co-immunoprecipitation experiments. The importance of these interactions was confirmed by mutagenesis where it was shown that mutations of any of the binding sites in DNA for the transcription factors or mutations in the amino acids involved in protein-protein interactions decreased the rate of transcrip-tion. Together, these studies suggest that IRF4/E47 interactions may play a key role in triggering locus activation. RNA-Seq data from HPV-positive samples and cell lines were analysed to identify putative biomarkers for cervical cancer. Infection with HPVs is the main cause for cervical cancer accounting for 10-15% of cancer-related deaths in women world-wide. It is established that HPVs escape the immune response over decades to es-tablish tumorigenesis but the specific mechanism is unknown. Virus integration into the host genome and deregulation of several genes may play a key role in promot-ing cancer; of particular interest are those transcripts that form the “surfacesome”. Among these, particular interest was given to connexin 26 (Cx26), which is classified as cancer-predisposition gene and was found to be commonly down regulated in all samples analysed. Recombinant adenoviruses expressing the two HPV16 oncogenes were generated and employed to transduce HaCaT cells to analyse Cx26 mRNA and protein levels coupled with dye transfer assays to study the structural behaviour of connexins. The data presented showed that E6 and E7 alter Cx26 protein expression by relocating Cx26 within the cytoplasm from the membrane-bound form. This was confirmed in the dye transfer assay where cell-cell communications were lost.
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Asderakis, Argiris. "Influence of cytokine gene polymorphisms on kidney transplant outcome : the case of IFN-γ." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493685.
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Samples from 93 of 115 consecutive cadaveric renal transplants were selected to define polymorphisms in both IFN-γ and IL-10. A 12 CA repeat IFN-γ polymorphic allele was found in 73 patients (70 in patients analysed further). This polymorphism was associated with high IFN-γ production in vitro. According to the presence or not of the 12 CA repeat allele patients were separated in high and low producer genotype groups. The incidence of acute rejection was 54.3% in this high IFN-γ genotype group, contrasting with 44.4% in the low IFN-γ. Requirement for ATG therapy was greater in the high IFN-γ group (odds ratio [OR]=2.5). Among HLA-DR-mismatched patients, IFN-γ high producer genotype was more strongly associated with rejection (OR=1.6). In the cyclosporine monotherapy subgroup, 11 out of 14 patients with IFN-γ high genotype (78%) had acute rejection (OR=2.88, p=0.09). Graft survival was similar between the two IFN-γ groups. When the analysis was controlled for the presence of delayed graft function, 40.5% of the high IFN-γ genotype patients had serum creatinine levels above 200 micromoles/L contrasting with only 14.3% of the low IFN-γ genotype recipients at 5 years after transplantation (p=0.05). In a regression model of creatinine at 1 year the significant variables were the presence of DGF, donor age greater than 50, greater than two rejection episodes, DR mismatch, donor female to male recipient sex, IL-10 high genotype, and IFN-γ high genotype. Conclusion: The 12 CA repeat IFN-γ polymorphic allele is associated with high IFN-γ production. We have shown that this high producer genotype for IFN-γ influences acute rejection in kidney transplantation, particularly in high-risk groups; it is also associated with worse long-term graft function.
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Ingram, Richard J. M. "Duodenal ulcer promoting gene : effects on the pathophysiology of Helicobacter pylori infection and the host immune response." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/42105/.
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Duodenal ulceration remains a significant problem. Helicobacter pylori infection is the major cause of duodenal ulcers (DU). Worldwide, around 1 in 2 people are chronically colonised by H. pylori, most of whom will not develop gastroduodenal disease, though some will develop DU whilst others will develop gastric ulcer or gastric carcinoma. The risk of disease is related to bacterial virulence factors, host and environmental factors. Disease-specific bacterial risk factors have not been established. Duodenal ulcer promoting gene (dupA) was proposed as a disease-specific bacterial virulence factor for DU. This study aims to examine the influence of dupA on clinical outcomes and whether these are epidemiologically consistent, if the dupA status of clinical isolates correlates with the key pathogenic features of DU in vivo, and if there is a biologically plausible role in disease through effects on host immune responses. Results showed that the influence of dupA status on clinical outcomes was not specific to DU, but rather that epidemiological associations link dupA with an increased risk of gastroduodenal diseases in general for some populations. The dupA status of clinical isolates did not correlate with the key pathogenic features of DU in vivo, though there was some evidence of increased gastric mucosal inflammation in association with dupA+ strains. Experimental results using a human blood immune cell model show that monocyte-derived cells mediate a more pro-inflammatory response through interaction with the dupA system. This might be the mechanism that explains the in vivo associations of dupA with inflammation and disease. In this study population, dupA did not satisfy the criteria of a true virulence factor that promotes duodenal ulceration. The assertion of this thesis is that dupA is misnamed.
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Monaco, G. "Computational approaches to study the immune system using gene expression and flow cytometry data." Thesis, University of Liverpool, 2017. http://livrepository.liverpool.ac.uk/3017054/.
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Lorenzoni, Marco. "Pro-Tumorigenic role of ETS-related gene (ERG) in precursor prostate cancer lesions." Doctoral thesis, Università degli studi di Trento, 2019. http://hdl.handle.net/11572/242659.
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Prostate cancer (PCa) is the second most common cancer in men with more than 1 million new cases worldwide each year. While some of the genomic, genetic and molecular events characterizing PCa have been functionally associated with tumor onset, development and resistance to therapy, the meaning of many other molecular alterations remains poorly understood. Recent development of organoids technology and prostate organoid cultures has established an innovative and valuable model for the study of adult tissue homeostasis, physiology and disease. In this project we combined prostate organoids technology with genetic engineering and CLICK-chemistry coupled Mass Spectrometry approaches in order to better characterize molecular features of wild type and genetically engineered mouse prostate organoids modeling early steps of human prostate tumorigenesis. In details, by manipulating mPrOs to proxy ETS-related gene (ERG) precursor PIN/HGPIN lesions of human prostate, we identified possible novel pro-tumorigenic roles of ERG which unleashes cells proliferation from the tight control of growth stimuli, and, even more interesting, corrupts immune system components to escape immune surveillance. In conclusion, this project shows that coupling innovative biological systems and technological approaches can lead to significant improvements in the analysis and understanding of disease mechanisms.
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Amlinger, Lina. "The type I-E CRISPR-Cas system : Biology and applications of an adaptive immune system in bacteria." Doctoral thesis, Uppsala universitet, Mikrobiologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-312234.
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CRISPR-Cas systems are adaptive immune systems in bacteria and archaea, consisting of a clustered regularly interspaced short palindromic repeats (CRISPR) array and CRISPR associated (Cas) proteins. In this work, the type I-E CRISPR-Cas system of Escherichia coli was studied. CRISPR-Cas immunity is divided into three stages. In the first stage, adaptation, Cas1 and Cas2 store memory of invaders in the CRISPR array as short intervening sequences, called spacers. During the expression stage, the array is transcribed, and subsequently processed into small CRISPR RNAs (crRNA), each consisting of one spacer and one repeat. The crRNAs are bound by the Cascade multi-protein complex. During the interference step, Cascade searches for DNA molecules complementary to the crRNA spacer. When a match is found, the target DNA is degraded by the recruited Cas3 nuclease. Host factors required for integration of new spacers into the CRISPR array were first investigated. Deleting recD, involved in DNA repair, abolished memory formation by reducing the concentration of the Cas1-Cas2 expression plasmid, leading to decreased amounts of Cas1 to levels likely insufficient for spacer integration. Deletion of RecD has an indirect effect on adaptation. To facilitate detection of adaptation, a sensitive fluorescent reporter was developed where an out-of-frame yfp reporter gene is moved into frame when a new spacer is integrated, enabling fluorescent detection of adaptation. Integration can be detected in single cells by a variety of fluorescence-based methods. A second aspect of this thesis aimed at investigating spacer elements affecting target interference. Spacers with predicted secondary structures in the crRNA impaired the ability of the CRISPR-Cas system to prevent transformation of targeted plasmids. Lastly, in absence of Cas3, Cascade was successfully used to inhibit transcription of specific genes by preventing RNA polymerase access to the promoter. The CRISPR-Cas field has seen rapid development since the first demonstration of immunity almost ten years ago. However, much research remains to fully understand these interesting adaptive immune systems and the research presented here increases our understanding of the type I-E CRISPR-Cas system.
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Xu, Yang. "A Systems Approach to Dissecting Immune Gene Regulatory Networks in the Modulation of Brain Function." eScholarship@UMMS, 2010. http://escholarship.umassmed.edu/gsbs_diss/924.
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Although the central nervous system was long perceived as the ivory tower without immune entities, there is growing evidence that the immune and nervous systems are intimated connected. These two systems have been shown to communicate both cellularly and molecularly under physiological and pathological conditions. Despite our increasing understanding of the interplay between these two systems, there are still numerous open questions. In this thesis, I address such unanswered questions related to: the role of microglia and their mechanism in contributing to pathologies in Rett syndrome; the beneficial effects of T-cell secreted cytokines in supporting social brain function; the evolutionary link of the interactions between the nervous and immune systems; the transcription regulation of a subset of microglia population in common neurodegenerative diseases.
Collectively, the current thesis is focused on the joint frontier of bioinformatics and experimental work in neuroimmunology. A multifaceted approach, that includes transcriptomics, genomics and other biomolecular modules, was implemented to unearth signaling pathways and mechanisms underlying the presenting biological phenomena. The findings of this thesis can be summarized as follows: 1) MeCP2 acts as a master regulator in the transcriptional repression of inflammatory stimuli in macrophages; 2) T-cell secreted IFN-γ supports social brain function through an evolutionally conserved interaction between the immune and nervous systems; 3) The APOE-TREM2 pathway regulates the microglia phenotype switch in neurodegenerative diseases. Provided that recent technologies allow for readily manipulating the immune system, the findings presented herein may create new vistas for therapeutic interventions in various neurological disorders.
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Xu, Yang. "A Systems Approach to Dissecting Immune Gene Regulatory Networks in the Modulation of Brain Function." eScholarship@UMMS, 2017. https://escholarship.umassmed.edu/gsbs_diss/924.
Full textAbstract:
Although the central nervous system was long perceived as the ivory tower without immune entities, there is growing evidence that the immune and nervous systems are intimated connected. These two systems have been shown to communicate both cellularly and molecularly under physiological and pathological conditions. Despite our increasing understanding of the interplay between these two systems, there are still numerous open questions. In this thesis, I address such unanswered questions related to: the role of microglia and their mechanism in contributing to pathologies in Rett syndrome; the beneficial effects of T-cell secreted cytokines in supporting social brain function; the evolutionary link of the interactions between the nervous and immune systems; the transcription regulation of a subset of microglia population in common neurodegenerative diseases.
Collectively, the current thesis is focused on the joint frontier of bioinformatics and experimental work in neuroimmunology. A multifaceted approach, that includes transcriptomics, genomics and other biomolecular modules, was implemented to unearth signaling pathways and mechanisms underlying the presenting biological phenomena. The findings of this thesis can be summarized as follows: 1) MeCP2 acts as a master regulator in the transcriptional repression of inflammatory stimuli in macrophages; 2) T-cell secreted IFN-γ supports social brain function through an evolutionally conserved interaction between the immune and nervous systems; 3) The APOE-TREM2 pathway regulates the microglia phenotype switch in neurodegenerative diseases. Provided that recent technologies allow for readily manipulating the immune system, the findings presented herein may create new vistas for therapeutic interventions in various neurological disorders.
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Macedo, Claudia. "O papel modulador do gene Aire (autoimmune regulator) sobre redes de expressão gênica em células tímicas epiteliais medulares." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-13042009-144302/.
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A expressão de antígenos restritos a tecidos (TRAs do inglês tissue restricted antigens) no timo pelas células epiteliais medulares (mTECs de medullary thymic epithelial cells) é essencial para a tolerância central das células T. Devido à sua heterogeneidade em termos de representação de autoantígenos, esse fenômeno foi denominado como expressão gênica promíscua (PGE de promiscuous gene expression), no qual o gene Aire (de autoimmune regulator) desempenha um papel como principal regulador transcricional positivo sobre um grande conjunto de TRAs dependentes de Aire. A proteína Aire tem a capacidade de interagir com seqüências específicas de DNA desempenhando um papel como regulador direto. Neste estudo utilizamos o método dos cDNA microarrays para acessar a PGE em células mTEC CD80+ murinas cultivadas in vitro. O agrupamento hierárquico dos dados permitiu a observação de que os genes de TRAs foram diferencialmente expressos. Para testar essa hipótese, inicialmente silenciamos o gene Aire pelo método de RNA interferente (RNAi) nas células mTEC. O agrupamento hierárquico dos dados de cDNA microarray mostrou um conjunto de genes de TRAs dependentes de Aire, os quais foram reprimidos após o silenciamento deste último. Redes gênicas reconstruídas desses dados permitiram a identificação de um nó gênico (Gucy2d) estabelecendo regulação positiva sobre genes downstream nas células mTEC normais. Entretanto, sob efeito do silenciamento de Aire, Gucy2d passou a ser um repressor. Esses resultados evidenciaram que genes da PGE estão conectados em rede, que um nó gênico pode atuar como intermediário no seu controle e que Aire na rede PGE desempenha seu controle como regulador upstream.The expression of tissue restricted antigens (TRAs) in thymus by medullary thymic epithelial cells (mTECs) is essential for the central selftolerance of T cells. Due to heterogeneity of autoantigen representation this phenomenon has been termed promiscuous gene expression (PGE), in which the autoimmune regulator (Aire) gene plays a role as main positive transcriptional regulator on a large set of Aire-dependent TRAs. Aire protein is able in binding to specific DNA sequence motifs and plays a role as a direct regulator. Here we used the cDNA microarray method to access PGE in murine CD80+ mTECs cultured in vitro. Hierarchical clustering of the data allowed observation that TRA genes were differentially expressed. To further investigate the control of PGE, we hypothesize that TRA genes establish networks contributing it selves to modulate their transcriptional levels. Aire in this case plays a role as upstream positive modulator. To test this hypothesis, initially we silenced Aire by gene knockdown (RNA interference) in mTECs. Hierarchical clustering of cDNA microarray data showed a set of Airedependent TRAs genes, which were down regulated after Aire silencing. Gene networks reconstructed from these data allowed the identification of a gene node (Gucy2d) establishing positive regulation upon downstream genes in normal mTECs. Nevertheless, under silencing of Aire, Gucy2d has become a repressor. These finding evidentiate that, genes features in PGE are connected in network; a gene node may act as intermediate in their control and that Aire in PGE network plays a role as an upstream regulator.
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Fernández, Bravo Ana. "Epidemiology and pathogenic characterization of species of the genus Aeromonas." Doctoral thesis, Universitat Rovira i Virgili, 2019. http://hdl.handle.net/10803/667146.
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El gènere Aeromonas inclou més de 32 espècies, algunes de les quals estan distribuïdes en el medi ambient i es consideren autòctones dels sistemes aquàtics. L'objectiu principal d'aquesta tesi va ser contribuir al millor coneixement de l'epidemiologia i la patogenicitat d'aquest gènere. En aquest treball s'ha investigat la presència d'Aeromonas en diferents mostres d'aigua demostrant que el mètode de floculació de llet desnatada utilitzat per a la detecció de virus sembla ser un bon mètode per a la detecció d'aquestes. A més, l'anàlisi d' A salmonicida, una espècie associada clàssicament amb malalties en peixos utilitzant un model de ratolí, va confirmar que aquesta espècie pot infectar mamífers amb diferents nivells de patogenicitat. Tenint en compte l'augment de les infeccions per Aeromonas en els últims anys, diferents col·laboracions amb hospitals universitaris s'han dut a terme. També es va demostrar que l'ús de MALDI-TOF per a la identificació d'Aeromonas aïllades de peixos era poc precisa a causa de les mancances a la base de dades. L'ús de genomes, la seva comparació i el desenvolupament de noves eines bioinformàtiques, va demostrar ser útil per entendre la potencial funció de les espècies en l'ambient. En aquesta tesi doctoral es va realitzat la caracterització de la metalochaperona HypA prèviament descrita en altres patògens, demostrant el paper en la tolerància a l'àcid de l'estómac i en la defensa d'Aeromonas contra macròfags. A més, s'ha demostrat el role de la toxina ExoA i el sistema de secreció tipus VI (SST6) en les infeccions mixtes que progressen en una fascitis necrotitzant, mitjançant l'estudi de soques aïllades d'un pacient d'Estats Units. Finalment,, un estudi de la defensa de monòcits humans contra Aeromonas es va dur a terme. Els resultats van demostrar una resposta immune espècie-específica, a més les espècies més prevalents en clínica presentaren una resposta més forta.El género Aeromonas incluye más de 32 especies, algunas de las cuales están distribuidas en el medio ambiente y se consideran autóctonas de los sistemas acuáticos. El objetivo principal de esta tesis fue contribuir al mejor conocimiento de la epidemiología y la patogenicidad de este género. En este trabajo se ha investigado la presencia de Aeromonas en diferentes fuentes de agua demostrando que el método de floculación de leche desnatada utilizado para detección de virus parece ser un buen método para la detección de estas. Además, el análisis de A. salmonicida, una especie asociada clásicamente con enfermedades en peces utilizando un modelo de ratón, confirmó que esta especie puede infectar mamíferos con diferentes niveles de patogenicidad. Teniendo en cuenta el aumento de las infecciones por Aeromonas en los últimos años, se han llevado a cabo colaboraciones con hospitales. También se demostró que el uso de MALDI-TOF para la identificación de Aeromonas aisladas de peces era poco precisa debido a las carencias en la base de datos. El uso de genomas, su comparación y el desarrollo de nuevas herramientas bioinformáticas, demostró ser útil para entender la función de las especies. En esta tesis doctoral se llevó a cabo la caracterización de la metalochaperona HypA previamente descrita en otros patógenos, demostrando el rol en la tolerancia al ácido del estómago y en la defensa de Aeromonas contra macrófagos. Además, se ha demostrado el rol de la toxina ExoA y el sistema de secreción tipo VI (SST6) en las infecciones mixtas que progresan en una fascitis necrotizante, mediante el estudio de cepas aisladas de un paciente de Estados Unidos. Finalmente, un estudio de la defensa de monocitos humanos contra Aeromonas se llevó a cabo. Los resultados demostraron una respuesta immune especie-específica, siendo más fuerte en las especies más prevalentes en clínica.
The genus Aeromonas includes more than 32 species, some of which are distributed in the environment and are considered to be indigenous to aquatic systems. The main objective of this thesis was to contribute to a better knowledge of the epidemiology and pathogenicity of this genus. In this work we have investigated the presence of Aeromonas in different water sources demonstrating the method of skimmed milk flocculation used for virus detection, it seems to be a good method for the detection of these bacteria. In addition, the analysis of A. salmonicida, a species classically associated with fish diseases using an in vivo model, confirmed that this species can infect mammals with different levels of pathogenicity. Considering the increase of infections by Aeromonas in recent years, different collaborations with university hospitals have been carried out to investigated different cases . It was also shown that the use of MALDI-TOF for the identification of Aeromonas spp isolated from clinical cases and fish was not precise due to the deficiencies in the database. The use of genomes, their comparison and the development of new bioinformatic tools, proved to be useful to understand the potential function of A. lusitana and A. salmonicida in the environment. In this doctoral thesis the metallochaperone HypA previously described with role in tolerance to stomach acid in other pathogens was characterized and in the defense of Aeromonas against macrophages. In addition, the role of the ExoA toxin and the type VI secretion system (T6SS) in mixed infections that progress in a necrotizing fasciitis have been demonstrated, using several mutant strains. Finally, a study of the defense of human monocytes against Aeromonas was performed. The results showed a species-specific immune response, that was higher in the most prevalent clinical species.
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Williman, Jonathan A., and n/a. "The use of the cytokines IFNγ, IL-12 and IL-23 to modulate immune responses raised by the gene gun method of DNA vaccination." University of Otago. Department of Microbiology & Immunology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20070405.151123.
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Since its discovery 15 years ago there has been an explosion of research in the field of DNA immunisation. Unfortunately despite early promises that DNA immunisation had the potential to cure almost any infectious disease, autoimmune disease or even cancer, progress towards clinical trials has been slow. This has been due in part to the huge range of permutations possible in delivering the DNA. One approach is to deliver the DNA by gene gun. Gene gun delivery is a very efficient way of transfecting cells however also has a number of possible disadvantages. These drawbacks include a weak immunogenicity in larger animals as well as the tendency to bias towards the development of a strong type 2 response.
In an effort to enhance antigen-specific immune responses and counter the type 2 polarisation of gene gun delivery, a series of DNA vaccines were created where the extracellular portion of the hemagglutinin (HA) gene from influenza A/PR8/34 virus was genetically fused the type 1 cytokines IFNγ, IL-12 and IL-23. Interleukin-23 has been recently discovered and even though both IL-12 and IL-23 contain the p40 subunit they seem to have dissimilar functions.
The vaccine constructs were first tested in cellular assays in vitro to ensure correct production and biological activity of the attached cytokines. They were then delivered in various combinations to groups of BALB/c mice to test development of immune responses and the effect of different delivery regimes. Finally mice were immunised then challenged with live influenza virus to determine the different DNA vaccines� protective efficacy.
DNA vaccines containing the HA gene alone (pHA) or fused to IFNγ (pIFNγHA), IL-12 (pIL-12HA) or IL-23 (pIL-23HA) were successfully constructed. The fusion of the HA gene to the genes for IFNγ, IL-12 or IL-23 did not significantly disturb the structure of the antigen or prevent the biological actions of the cytokines. Mice immunised three times with pHA had high titres of serum IgG1 antibody and their splenocytes produced approximately equal amounts of IFNγ and IL-5. Co-delivery of IFNγ was unable to alter immune responses regardless of whether it was delivered at the first, last or during all immunisations. Surprisingly co-delivery of IL-12 acted to suppress both antibody and cellular immune responses, possibly through an IFNγ/nitric oxide feedback loop. On the other hand co-delivery of IL-23 tended to enhanced immune responses and, while it did not significantly alter the type 1 to type 2 balance, it was able to increase the ability of mice to clear live influenza virus from their lungs when they were challenged 26 weeks after immunisation. This protection was associated with increased levels of neutralising antibody in the serum of pIL-23HA immunised mice.
This research has illuminated several of the pitfalls in the development of DNA vaccines and the use of cytokine as adjuvants. However it has also broadened our understanding of IL-23 and implies that IL-23 could be effectively used to increase the development of longterm immunity after immunisation.
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Brown, David Spaulding. "CD4+ T Cell Responses: A Complex Network of Activating and Tolerizing Signals as Revealed by Gene Expression Analysis: A Dissertation." eScholarship@UMMS, 2005. https://escholarship.umassmed.edu/gsbs_diss/230.
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Immunologic self-tolerance is maintained by both central and peripheral mechanisms. Furthermore, regulation of mature lymphocyte responses is governed by inhibitory as well as stimulatory signals. TCR recognition of cognate peptide bound to MHC molecules provides the initial stimulus leading to T lymphocyte activation and determines the antigen specificity of any subsequent response. However, lymphocytes must discriminate between foreign and self antigens presented by self-MHC molecules to maintain self tolerance and avoid pathological autoimmunity. Consequently, TCR ligation alone is reported to result in abortive activation, T cell anergy, apoptosis, and tolerance. Under normal physiological conditions, costimulatory signals modify lymphocyte responsiveness to TCR ligation to prevent autoimmunity while enabling robust responses to foreign antigen. Members of the CD28/B7 superfamily provide the critical secondary signals essential for normal immune cell function.
CD28 is an essential positive costimulatory molecule with critical functions in thymic development, lineage commitment, and regulation of peripheral lymphocyte responses to antigenic stimuli. CD28 ligation by APC-expressed B7 molecules alters proximal signaling events subsequent to MHC/TCR interactions, and initiates unique signaling pathways that alter mRNA stability and gene transcription. Furthermore, CD28 signaling is required for regulatory T cell development and function. Thus, CD28 has a central role in both potentiating lymphocyte activation mediated by TCR engagement and regulating peripheral tolerance. In contrast, Ctla-4 mediates an inhibitory signal upon binding B7 molecules on an antigen-presenting cell. Its importance in governing lymphocyte responses is manifested in the fatal lymphoproliferative disorder seen in Ctla-4-/- mice. The lymphocyte proliferation is polyclonal, antigen and CD28 dependent, and arises from defects in peripheral CD4+T cell regulation. The high percentage of peripheral T lymphocytes expressing activation markers is accompanied by lymphocyte infiltration into numerous non-lymphoid tissues and results in death by 3-4 weeks. While still controversial, Ctla-4 signaling has been reported to be essential for induction of peripheral T lymphocyte tolerance in vivo and in some model systems is proposed to regulate both T lymphocyte anergy induction and the immune suppressive effects of some regulatory T cells in the prevention of autoimmunity.
Signaling pathways activated by TCR ligation and CD28 costimulation have been extensively characterized. In contrast, the mechanisms mediating Ctla-4 maintenance of tolerance remain largely unknown. Ctla-4 gene expression is tightly controlled during T cell development and activation, and its intracellular localization and expression on the cell surface is regulated by numerous pathways and intermediates. While a tailless Ctla-4 mutant is capable of inhibiting T cell activation, recent studies have shown that a ligand independent form of Ctla-4 is also capable of providing an inhibitory signal to T lymphocytes. In conjunction with the strictly controlled expression kinetics and the perfect amino acid homology between the intracellular domains of mouse and human Ctla-4, this data suggests that Ctla-4 may participate in the modulation or initiation of intracellular signaling pathways.
Positive and negative costimulatory receptors on the T cell modify lymphocyte responses by altering both quantitative and qualitative aspects of the lymphocyte response including threshold of activation, cytokine secretion, and memory responses. Positive costimulation augments T cell responses, in part, by downregulating the expression of genes that actively maintain the quiescent phenotype. This study was initiated to determine the role of Ctla-4 ligation in modifying the global gene expression profile of stimulated T cells and to determine if the Ctla-4 mediated maintenance of T cell tolerance was achieved, in part, by altering the transcription of quiescence genes necessary for the prevention of T cell activation subsequent to TCR and CD28 stimulation.
Previous studies investigating the influence of Ctla-4 ligation on transcriptional profiles of activated lymphocytes detected only quantitative alterations in the transcriptional regulation initiated by CD28 signaling. In contrast, our data suggests that quantitative effects of Ctla-4 ligation that differentially influence pathways acting downstream of stimulatory receptors results in a stable and qualitatively unique phenotype detectable at the level of the transcriptome. Thus, the cumulative effect of Ctla-4 signaling is unique and not constrained to reversing alterations in expression initiated by CD28. In addition, Ctla-4 ligation can be shown to influence T lymphocyte responsiveness and the resulting global expression profile within 4 hours after stimulation and prior to detectable Ctla-4 surface expression. In a subpopulation of T cells, TCR stimulation activates pathways that result in commitment to activation with 2-6 hours. In contrast, CD28 signaling must be maintained for 12-16 hours to ensure maximal responses at the population level. The period of sensitivity to Ctla-4 inhibition of activation is more constrained and does not extend beyond 12 hours. Together, these data support a potential role for Ctla-4 in modification of the early transcriptional response and may explain various alterations in phenotype resulting from Ctla-4 ligation that have been reported in secondary responses.
Identification of genes involved in lymphocyte activation, maintenance of selftolerance, and attenuation of immune responses opens the door to therapeutic manipulation of the pathways implicated. CD28 costimulation results in general amplification of TCR-initiated transcriptional responses, and specifically alters the expression profile of a subset of genes. In contrast, Ctla-4 ligation directly and specifically alters the expression of a select group of genes when ligated, and results in minimal suppression of the global CD28-mediated costimulatory transcriptional response. Ctla-4 regulated genes comprise a heterogeneous family, but include known quiescence factors, transcriptional regulators, and various determinants of cell cycle progression and senescence. The role of Ctla-4 in maintaining self-tolerance indicates that targeted manipulation of these gene products presents a novel therapeutic opportunity, and suggests that the mechanisms involved in Ctla-4-mediated maintenance of peripheral T cell tolerance and regulation of immune responsiveness is more nuanced than previously thought. In addition, this study provides the most comprehensive description of global gene expression during primary lymphocyte activation yet available. The integration of statistical and bioinfomatics analyses with large scale data mining tools identifies genes not previously characterized in lymphocytes and can direct future work by predicting potentially interacting gene products and pathways.
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Gallwitz, Maike. "Sculpted through Time : Evolution and Function of Serine Proteases from the Mast Cell Chymase Locus." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7379.
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Johansson, Martin. "Systemic lupus erythematosus and rheumatoid arthritis analyses of candidate genes involved in immune functions, for susceptibility and severity /." Doctoral thesis, Umeå : Umeå university, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-30388.
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Mattana, Teresa Cristina Colvara. "Variantes do gene CD226 associadas com a susceptibilidade ao diabetes mellitus tipo 1 autoimune." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/5/5135/tde-26102012-103243/.
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Recentemente, estudos de Genome Wide Association (GWA) identificaram uma nova região cromossômica, 18q22, como de susceptibilidade ao Diabetes tipo 1 autoimune (DM1A). Nesta região localiza-se o gene CD226, responsável por codificar uma molécula de adesão leucocitária (CD226) envolvida no processo de adesão celular, diferenciação de células T CD4+ virgens, citotoxicidade induzida por células natural killer (NK) e produção de citocinas. Até o momento, apenas o polimorfismo rs763361 A/G foi relacionado ao diabetes autoimune e pouco é conhecido quanto ao envolvimento de outras variantes do CD226, associadas a outras doenças autoimunes, na patogênese do DM1A. Com o objetivo de definir as variantes polimórficas relacionadas à susceptibilidade ao DM1A, às suas características fenotípicas e outras manifestações de autoimunidade, 532 pacientes diabéticos tipo 1A e 594 controles normais foram envolvidos neste estudo. Inicialmente, em um subgrupo de 106 diabéticos e 102 controles, as regiões codificadoras e flanqueadoras do gene CD226, obtidas do DNA genômico de leucócitos do sangue periférico, foram amplificadas pela técnica de Reação em Cadeia da Polimerase e submetidas à sequenciamento direto. Em uma segunda etapa, os polimorfismos rs763361, rs1788101 e rs727088 foram genotipados pelo ensaio TaqMan nos demais pacientes e controles. Resultados: foram identificadas 12 variantes no gene CD226, sete com frequência acima de 5%. Nenhuma variante nova foi encontrada. A variante rs727088 não estava em equilíbrio de Hardy Weinberg no grupo controle. Os genótipos AA da variante rs763361 e CC do rs727088 foram associados ao risco de DM1A e estavam em desequilíbrio de ligação. O genótipo do haplótipo ACAC, formado pelas variantes de risco, predominou nos pacientes diabéticos. Tanto o genótipo AA do rs763361 como o CC do rs727088 e o genótipo do haplótipo ACAC foram associados com menores valores de peptídeo C em pacientes com até dois anos de duração da doença. Nenhum polimorfismo influiu na presença de autoanticorpos pancreáticos e extra-pancreáticos. Conclusão: O genótipo AA da variante rs763361 do gene CD226 predispõe ao diabetes autoimune na nossa população, assim como a menores valores de Peptídeo C, contribuindo para a maior agressividade da doença. Dados da variante rs727088 devem ser analisados com cautela devido à falta de equilíbrio de Hardy Weinberg no grupo dos controlesRecently, Genome Wide Association (GWA) studies identified a new locus, 18q22, as a canditate to Type 1 A, or immune mediated diabetes (T1AD) susceptibility. This locus harbors the CD226 gene, responsible for encoding the leukocyte adhesion molecule (CD226) involved in cell adhesion, differentiation of naïve CD4+T cells, cytotoxicity induced by natural killer (NK) cells and cytokine production. Although just one single nucleotide polymorphism (SNP) rs763361 A/G had been related to T1AD, little is known about the involvement of new variants of CD226, implicated in other autoimmune disorders, in the pathogenesis of T1AD. In order to identify polymorphic variants related to T1AD susceptibility and their influences in phenotypic characteristics and other manifestations of autoimmunity, 532 type 1A diabetic patients and 594 health controls were enrolled in this study. Initially, in a subset of 106 diabetics and 102 controls, coding and flanking regions of CD226 gene obtained from genomic DNA extraction were amplified by polymerase chain reaction technique and subjected to direct sequencing. In a second step, the polymorphisms rs763361, rs727088 and rs1788101 were genotyped by TaqMan assay in the remaining patients and controls. Results: 12 variants in CD226 gene, seven of them with frequency above 5 % where identified. We did not found new variants. The variant rs727088 was not in Hardy Weinberg equilibrium in the control group. The genotypes AA (OR=1.45; p=0.005) and CC (OR=1.41; p=0.01) related to rs763361 and rs727088 variants respectively, were associated with risk of T1AD. Both predominated in female (p<0.01). Further, these variants were in linkage disequilibrium. The genotype haplotype ACAC formed by the risk variants was more frequent in patients with diabetes (30.5% x 25.6%; OR=1.42; p=0.014). The AA genotype of rs763361, the CC genotype and ACAC genotype haplotype were associated with lower levels of C-peptide in patients with no more than two years of disease course. The presence of pancreatic and extra-pancreatic autoantibodies was not associated with CD226 SNPs. Conclusion: The AA genotype of rs763361 variant of the gene CD226 predisposes to autoimmune diabetes in our population, as well as to lower levels of C-peptide, contributing to the aggressiveness of the disease. It predominated in female. Data of rs727088 variant should be analyzed with caution due to the lack of Hardy Weinberg equilibrium in the control group
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Fornari, Thaís Arouca. "Análise da expressão gênica promíscua no timo de camundongos NOD (non obese diabetic) durante a emergência do Diabetes melitus tipo 1." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-13042009-150027/.
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A tolerância imunológica é a propriedade essencial do sistema imune que controla as reações patológicas contra antígenos do próprio. O timo é visto como o principal órgão envolvido com a indução de tolerância aos antígenos próprios que são expressos pelas células tímicas (tolerância central), enquanto que a indução de tolerância aos antígenos relacionados a outros tecidos (TRAs) tem sido atribuída aos mecanismos de tolerância extratímica (tolerância periférica). Entretanto, a evidência da expressão de TRAs de órgãos e tecidos parenquimais no timo pelas células medulares epiteliais (mTECs) de camundongos e de humanos a qual foi referida como expressão gênica promíscua (PGE) reforçou a concepção de tolerância central de TRAs. O controle molecular dessa expressão tem sido atribuído ao gene Aire (Auto immune regulator) que é um regulador de transcrição. No presente estudo, procurou-se retratar a expressão gênica promíscua no timo de camundongos NOD (Non Obese Diabetic) por meio da análise da expressão gênica em grande escala, ou seja, descrevendo seu transcriptoma usando a tecnologia de cDNA microarrays. Para a análise dos dados utilizamos programas de bioinformática dedicados a microarrays bem como dados de bancos para a caracterização da PGE e susceptibilidade genética ao diabetes melitus do tipo 1 (DM-1). Três conjuntos de resultados puderam ser evidenciados. No primeiro conjunto observou-se a ocorrência da PGE de antígenos tecidos/órgãos parenquimatosos (TRAs) em timos recém removidos e em in vitro em cultura ATOC de camundogos NOD pré-autoimunes e autoimunes (diabéticos). O segundo conjunto de resultados consistiu na análise do efeito da inativação do transcrito de gene Aire na expressão gênica do timo de camundongos NOD in vitro em cultura ATOC. Finalmente, no último conjunto de dados, demonstrou-se que certos genes de TRAs com expressão promíscua, se encontram em regiões cromossômicas de susceptibilidade ao DM - 1 (idds). Como três deles (Il-4, Cd4 e Cdk4) são diretamente relacionados com a patogenia do DM-1 em camundongos foi possível estabelecer um paralelo entre PGE e susceptibilidade genética.Immunologic tolerance is an essential property of the immune system, which controls immune reactions directed against the body self components. The thymus is seen as the main organ involved with the tolerance induction to self antigens, which are expressed by the thymic cells (central tolerance), while the tolerance induction to the diverse other peripheral tissues and organs is attributed to extra thymic mechanisms (peripheral tolerance). Nevertheless, the evidence for the expression of peripheral tissue related antigens (TRAs) in the thymus by the medullary thymic epithelial cells (mTECs) of mice and humans, which have been termed to as promiscuous gene expression (PGE), has contributed to the concept of central tolerance to TRAs. The molecular control of such gene expression has been attributed to the Aire (autoimmune regulator) gene, which plays a role as a transcriptional regulator. In the present study, we searched to picture PGE in the thymus of NOD (non obese diabetic) mice by means of high throughput gene expression, analyzing the transcriptome by the cDNA microarray method. To analyzing data we used bioinformatics programs dedicated to microarrays and specialized data banks to characterize PGE and genetic susceptibility to type 1 diabetes mellitus (DM-1). Studying pre and autoimmune NOD mice, we evidentiate three sets of results. In the first set, it was observed the occurrence of PGE of parenchymal tissue/organs antigens (TRAs) in fresh thymuses and in thymuses cultured in vitro in adult thymus organ cultures (ATOC). The second set of results consisted in the analysis of the effect of in vitro (ATOC) Aire gene silencing on PGE. Finally, in the third data set, we demonstrated that certain promiscuously expressed genes are positioned in DM-1 genetic susceptibility chromosomal regions (idds). As three of such genes (IL4, Cd4 and Cdk4) are directly associated to the DM-1 pathogenesis in mice, it was possible to establishing a parallel between PGE in the thymus and genetic susceptibility to this autoimmune disease.
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Zhang, Fengmin. "Resistance to Friend Murine Leukemia Virus Infection Conferred by the Fv-4 Gene is Recessive but Appears Dominant From the Effect of the Immune System." Kyoto University, 2001. http://hdl.handle.net/2433/150599.
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Schultis, Kim [Verfasser], and Bianca [Akademischer Betreuer] Schaub. "Potential biomarkers for the prediction of childhood wheeze : insights into new gene regulation mechanisms of the innate immune system at birth / Kim Schultis ; Betreuer: Bianca Schaub." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://d-nb.info/1218465875/34.
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Mexal, Sharon. "Differential expression in the hippocampus of schizophrenic and control smokers : a high-throughput analysis of the effects of psychopathology, smoking, and postmortem brain parameters on gene expression /." Connect to full text via ProQuest. IP filtered, 2005.
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Pietrzak, Elżbieta. "Wpływ galaktooligosacharydów na modulację ekspresji genów związanych z układem immunologicznym ptaków i ryb." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2020. http://dlibra.utp.edu.pl/Content/3212.
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Celem pracy było określenie wpływu galaktooligosacharydów GOS (oligosacharydów regulujących skład mikrobioty jelitowej oraz modulijącuch odpowiedź immunologiczną gospodarza) na modulację ekspresji genów związanych z układem immunologicznym ptaków i ryb. Wykazano, że stosowanie prebiotyku GOS w praktyce hodowlanej z wykorzystaniem metody in ovo lub jako dodatek paszowy, może przyczynić się do poprawy zdrowotności zwierząt w produkcji drobiarskiej oraz akwakulturze
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Narayan, Kavitha. "The Function of Innate γδ T Cell Subsets is Molecularly Programmed in the Thymus in Three Stages: A Dissertation." eScholarship@UMMS, 2011. https://escholarship.umassmed.edu/gsbs_diss/527.
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The immune system generates discrete lineages of cells that are designed to respond optimally to environmental cues and infectious agents. Two distinct lineages of T cells, distinguished by expression of either an αβ or γδ T cell receptor (TCR), arise from a common progenitor in the thymus. The type of pathogen and the cytokine milieu directs effector differentiation of αβ T cells in the periphery through the induction of specific transcriptional networks. γδ T cell development is distinct from that of αβ T cells in its ordered rearrangement of TCR genes and the pairing of Vγ and Vδ chains to generate γδ T cell subsets that home to specific tissues. Unlike conventional αβ T cells, γδ T cells express a preactivated or memory phenotype prior to pathogen encounter, and recent evidence indicates that effector functions may be programmed during thymic development. To better understand the development and function of γδ T cells, we analyzed the gene expression profiles of subsets of γδ T cells segregated by TCR repertoire and maturation state in the thymus. We also determined the impact of TCR signaling and trans-conditioning on γδ T cell subset-specific gene signatures by analysis of Itk-/- and Tcrb-/- γδ T cell subsets. Our analysis has defined three stages of γδ T cell subset-specific differentiation, and indicates that γδ T cells may consist of at least two separate lineages, distinguished by the expression of a Vγ2 or Vγ1.1 TCR, that arise from different precursors during thymic development. Key transcriptional networks are established in immature γδ T cells during the first phase of development, independent of TCR signaling and trans-conditioning, with Vγ2+ cells expressing modulators of WNT signaling, and Vγ1.1+ cells expressing high levels of inhibitor of DNA binding 3 (ID3), which regulates E2A/HEB proteins. The second stage involves the further specification of the Vγ2+ subset specific gene signature, which is dependent upon ITK-mediated signals. In the third stage, terminal maturation of γδ T cell subsets occurs, dependent on both TCR and trans-conditioning signals. The expression patterns of Vγ1.1+ subsets that differ in Vδ usage diverge, and all subsets further elaborate and reinforce their effector programming by the distinct expression of chemokine and cytokine receptors. Alteration of WNT signaling or E2A/HEB activity results in subset specific defects in effector programming, indicating that the transcriptional networks established at the immature stage are crucial for the functional maturation of γδ T cells. These data provide a new picture of γδ T cell development, regulated by multiple checkpoints that shape the acquisition of subset-specific molecular signatures and effector functions.
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Bitter, Sondhja. "Influence of specific farming activities of pregnant mothers on gene-expression of CD14 and toll-like receptors of the newborn : indicators for prenatal priming of the immune system /." Basel, 2007. http://www.public-health-edu.ch/new/Abstracts/BS_07.04.08.pdf.
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Trotta, Maria Beatriz Fortunato. "Mecanismos inflamatórios e imunológicos na síndrome de Down." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5131/tde-04032010-175343/.
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Nos últimos anos houve um aumento da expectativa de vida de indivíduos com síndrome de Down, com causas de morte que diferem da população em geral. Alguns estudos mostraram que a resposta imunológica difere ao longo da vida com alterações relacionadas ao envelhecimento. O gene RCAN1 (regulador de calcineurina tipo 1), localizado na região q22.12 no cromossomo 21 é descrito como responsável pelo fenótipo da SD. O gene RCAN1 inibe a ação da calcineurina, responsável pela desfosforilação do fator nuclear de células T ativadas (NFAT), uma etapa essencial para a ativação de genes responsáveis pela expressão de citocinas. A consequência é uma possível diminuição da resposta imune efetora. Em adultos com síndrome de Down as respostas imunes humoral e celular têm sido pouco investigadas. Apesar da superexpressão do gene RCAN1 já ter sido descrita em diversos tecidos, sua expressão em células mononucleares de sangue periférico (PBMC) de adultos não foi ainda avaliada. Os objetivos deste estudo foram avaliar aspectos humorais e celulares da resposta imune, avaliar a expressão quantitativa do gene RCAN1 e relacionar os achados com a produção de citocinas. O grupo de estudo foi composto de adultos com síndrome de Down (SD) com cariótipo de trissomia livre (n=24), um grupo controle (CTR) composto de deficientes mentais com outras etiologias (n=21) e um grupo de indivíduos saudáveis (n=8), como parâmetros para alguns experimentos. Os grupos SD e CTR convivem na Associação de Pais e Amigos dos Excepcionais (APAE-SP). Foram realizados hemogramas e sorologias para detecção de hepatite B, citomegalovírus, mononucleose infecciosa, toxoplasmose, rubéola, sarampo, PCR, fração de complemento C3, C4, antiestreptolisina O e dosagem de imunoglobulinas IgG, IgM e IgA. Células mononucleares foram obtidas por gradiente de Ficoll-Hypaque e submetidas à cultura celular, análise quantitativa de expressão gênica de RCAN1 e avaliação imunofenotípica por citometria de fluxo. Os sobrenadantes da cultura foram coletados para dosagem das citocinas IL-2, IL-4, IL-5, IL-10, TNF e INF. Os resultados deste estudo mostraram que a frequência de sorologias positivas para os vários agentes infecciosos e os demais parâmetros imunológicos foram comparáveis nos dois grupos de doentes mentais. A análise imunofenotípica dos indivíduos com SD mostrou aumento de células NK, de linfócitos TCD8+, alteração na relação CD4:CD8 (1:1) e diminuição de linfócitos B (CD19+) quando comparados ao grupo controle (p<0,05). A produção espontânea de INF, TNF e IL-10 foi maior no grupo SD em relação ao grupo CTR (p<0,05). Porém, quanto à expressão do gene RCAN1, não foi observada diferença entre os dois grupos analisados. O estudo do perfil imunológico humoral e celular de adultos com síndrome de Down provenientes da APAE-SP permitiu concluir que não houve diferenças quanto aos aspectos humorais avaliados nos dois grupos (SD e CTR). Quanto aos aspectos celulares, a imunofenotipagem sugere um possível sinal de envelhecimento precoce do sistema imune e a produção de citocinas um predomínio de perfil pró-inflamatório. Contudo, o perfil de citocinas não apresenta relação com o nível de expressão do gene RCAN1.In recent years there has been an increase in life expectancy of individuals with Down´s syndrome (DS), with death causes differ from the general population. Some studies have shown that the immune response differs throughout life with changes related to aging. The RCAN1 gene (regulator of calcineurin type 1), located in the q22.12 region of chromosome 21 is described as responsible for the phenotype of DS. The gene RCAN1 inhibits the calcineurin activity, responsible for the dephosphorylation of the nuclear factor of activated T cells (NFAT), an essential step for the activation of the genes responsible for cytokines expression. The consequence is a possible reduction of the effector immune response. In adults with DS, the humoral and cellular immune responses have not been throughly investigated. Although the overexpression of the RCAN1 gene has already been described in many tissues, its expression in mononuclear cells of peripheral blood (PBMC) of adults with DS has not been evaluated. The objectives of this study were to evaluate aspects of humoral and cellular immune response, evaluate the quantitative expression of the RCAN1 gene and correlate the findings with the production of cytokines. The study group consisted of adults with Down´s syndrome (DS) with free trisomy karyotype (n = 24), a control group (CTR) composed of the mentally disabled of other etiologies (n = 21) and a group of healthy subjects (n = 8), as parameters for some experiments. The SD and CTR groups are followed in Associação de Pais e Amigos dos Excepcionais (APAE-SP). It was evaluated Hemogram and serology for detection of hepatitis B, cytomegalovirus, infectious mononucleosis, toxoplasmosis, rubella, measles, cRP, complement fraction C3, C4, antistreptolysin O and IgG, IgM and IgA immunoglobulin isotypes. The mononuclear cells were obtained by Ficoll-Hypaque gradient and the cells were cultured without stimuli, analyzed for the quantitative gene expression of RCAN1 and evaluated for immunophenotyping by flow cytometry. The culture supernatants were collected for measurement of cytokines IL-2, IL-4, IL-5, IL- 10, TNF and IFN.The results of this study showed that the frequency of positive tests for various infectious agents and other immunological parameters were comparable in both groups (DS and CTR). Immunophenotyping of individuals with DS showed an increase in NK cells, CD8 + lymphocytes, changes in CD4: CD8 ratio (1:1) and decreased B lymphocytes (CD19 +) when compared to the control group (p <0.05). The DS group had a spontaneous production of IFN, TNF and IL-10 higher than the CTR group (p<0.05). However, there was not any difference in RCAN1 gene expression (mRNA) between the two groups of the mentally disabled. The humoral and cellular immune profile in adults with Down´s syndrome from APAE-SP showed that there was no difference in the humoral aspects assessed in both groups (SD and CTR). For the cellular aspects, the immunophenotyping suggests a possible sign of premature aging of the immune system and the cytokine production show a proinflammatory profile. Nevertheless, this cytokines profile is not associated with level of expression of the RCAN1 gene.
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Richards, Kathryn H. "Mutations in the vpu and env Genes of HIV-1 Can Adversely Impact Infectivity: A Dissertation." eScholarship@UMMS, 2008. https://escholarship.umassmed.edu/gsbs_diss/378.
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The Human Immunodeficiency Virus (HIV) is able to infect CD4+ T cells as well as macrophages. Macrophage-tropism has been linked to determinants in the envelope of HIV. These determinants allow envelopes to exploit low levels of CD4 for infection. Macrophages are an important reservoir of virus, especially during chronic infection, and are likely responsible for the bulk of virus produced after CD4+T cells have declined. Viral factors that may impact the ability to infect macrophages are worth studying because this cell type is so important in infection.
It was previously reported that the macrophage-tropic primary isolate AD8 was vpu-independent. The molecular clone YU-2, derived from brain tissue without culture, was also reported to be macrophage-tropic despite having a mutation in the vpu start codon. It was therefore possible that vpu-independent envelopes could evolve in vivo. To examine this possibility, I constructed chimeras containing wild type or defective vpu start codons, and gp160 sequences from AD8, YU-2 or SF162 (a vpu-dependent control). I also used full length AD8 and YU-2 with wild type or defective vpu start codons. I infected macrophages with equal amounts of virus, and measured viral output over two weeks. Viruses with defective vpu start codons were released to lower levels compared to their wild type vpucounterparts. In contrast to previous reports, the AD8 envelope is not vpu-independent for replication in macrophages. The YU-2 envelope is also not vpu-independent.
Macrophage-tropic envelopes from late stages of infection can be sensitive to antibodies that bind the CD4 binding site on gp120, implying that macrophage-tropic envelopes have more exposed CD4 binding sites. Neutralizing antibodies may act as modulators of macrophage-tropism over the course of infection. Using chimeras containing gp120 sequences derived from the PBMC of four HIV+patients, I examined the capacity for envelopes to infect macrophages. Three patients (MM1, 4, and 8) had macrophage-tropic envelopes before and after developing autologous neutralizing antibodies. Three patients (MM1, 4, and 23) developed heterologous antibodies against IIIB, an easily neutralized T-cell line adapted strain of HIV-1. This data indicates that macrophage-tropism in these patients is not modulated by the presence of neutralizing antibodies.
The macrophage-tropism of envelopes tends to segregate depending on the tissue origin of the virus. Envelopes from two separate tissues from the same patient exhibit very different infectivity characteristics. The B33 envelope, from brain tissue, is very infectious and is macrophage-tropic, while the LN40 envelope, from lymph node tissue, is weakly infectious and is not macrophage-tropic. Replacing the entire gp41 of LN40 with that of B33 restores some infectivity to LN40. The cytoplasmic domain of gp41 contains many motifs important for assembly and infectivity. To examine which motifs are responsible for the weak infectivity of LN40, I made chimeras of gp41, as well as point mutations in gp41. The LN40 chimera containing the entire gp41 of B33 restored the most infectivity. Point mutations in the palmitoylation site, Pr55gagbinding region, and dileucine motif at the C-terminus also restored infectivity when combined. Determinants in the gp41 cytoplasmic domain are responsible for the weak infectivity of LN40; however, it is possible that there are contributing determinants in gp120, such as the ability to use low levels of CD4.
Here, I examined how changes in the vpu and env genes of HIV-1 can impact infectivity, especially infectivity of macrophages. Changes that adversely impact the virus’ ability to infect macrophages may also impact the overall course of disease. However, the data here show that retaining the ability to infect, and replicate in, macrophages give HIV an advantage. I speculate that retaining the ability to infect macrophages gives the virus a reservoir for later in disease, when CD4+ T cells have been depleted, as well as way of avoiding neutralizing antibodies. This work further defines the importance of macrophages in HIV-1 infectivity and disease.
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Chiu, Ya-Lin. "HIV-1 Gene Expression: Transcriptional Regulation and RNA Interference Studies: a Dissertation." eScholarship@UMMS, 2003. https://escholarship.umassmed.edu/gsbs_diss/118.
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Gene expression of human immunodeficiency virus type-1 (HIV-1), which causes Acquired Immunodeficiency Syndrome (AIDS), is regulated at the transcriptional level, where negative factors can block elongation that is overcome by HIV Tat protein and P-TEFb. P-TEFb, a positive elongation transcription factor with two subunits, CDK9 and Cyclin T1 (CycT1), catalyzes Tat-dependent phosphorylation of Ser-5 in the Pol II C-terminal domain (CTD), allowing production of longer mRNAs. Ser-5 phosphorylation enables the CTD to recruit mammalian mRNA capping enzyme (Mce1) and stimulate its guanylyltransferase activity. This dissertation demonstrates that stable binding of Mce1 and cap methyltransferase to template-engaged Pol II depends on CTD phosphorylation, but not on nascent RNA. Capping and methylation doesn't occur until nascent pre-mRNA become 19-22 nucleotides long. A second and novel pathway for recruiting and activating Mce1 involved direct physical interaction between the CTD, Tat and Mce1. Tat stimulated the guanylyltransferase and triphosphatase activities of Mce1, thereby enhancing the otherwise low efficiency of cotranscriptional capping of HIV mRNA. These findings imply that multiple mechanisms exist for coupling transcription elongation and mRNA processing at a checkpoint critical to HIV gene expression.
To elucidate P-TEFb's function in human (HeLa) cells, RNA interference (RNAi) was used to degrade mRNA for hCycT1 or CDK9. Down-regulation of P-TEFb expression by RNAi can be achieved without causing major toxic or lethal effects and can control Tat transactivation and HIV replication in host cells. High-density oligonucleotide arrays were used to determine the effect of P-TEFb knockdown on global gene expression. Of 44,928 human genes analyzed, 25 were down-regulated and known or likely to be involved in cell proliferation and differentiation. These results provide new insight into P-TEFb function, its potent role in early embryonic development and strong evidence that P-TEFb is a new target for developing AIDS and cancer therapies.
To fulfill the promise of RNAi for treating infectious and human genetic diseases, structural and functional mechanisms underlying RNAi in human cells were studied. The status of the 5' hydroxyl terminus of the antisense strand of short interfering RNA (siRNA) duplexes determined RNAi activity, while a 3' terminus block was tolerated in vivo. A perfect A-form helix in siRNA was not required for RNAi, but was required for antisense-target RNA duplexes. Strikingly, crosslinking siRNA duplexes with psoralen did not completely block RNAi, indicating that complete unwinding of the siRNA helix is not necessary for RNAi in vivo. These results suggest that RNA amplification by RNA-dependent RNA polymerase is not essential for RNAi in human cells.
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Melichar, Heather J. "SOX13, A γδ T Cell-Specific Gene, Is a WNT-Signaling Antagonist Regulating T Cell Development: A Dissertation." eScholarship@UMMS, 2006. https://escholarship.umassmed.edu/gsbs_diss/251.
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Mature αβ and γδ T cells arise from a common precursor population in the thymus. Much debate has focused on the mechanism of T cell lineage choice made by these multi-potential precursor cells. It is widely believed that the decision of these precursor cells to commit to the γδ or αβ T cell lineages is regulated primarily by a specific instructive signal relayed through the appropriate T cell receptor. Contrary to this model, we present evidence for a TCR-independent lineage commitment process. Comparison of global gene expression profiles from immature αβ and γδ lineage thymocytes identified Sox13, an HMG-box transcription factor, as a γδ T cell-specific gene. Unlike other HMG-box transcription factors such as TCF1, LEF1 and SOX4, that are critical for proper αβ T cell development, Sox13 expression is restricted to early precursor subsets and γδ lineage cells. Importantly, SOX13 appears to influence the developmental fate of T cell precursors prior to T cell receptor expression on the cell surface. Transgenic over-expression of Sox13 in early T cell precursors strongly inhibits αβ lineage development, in part, by inhibiting precursor cell proliferation and concomitantly, leading to increased cell death among αβ lineage subsets. Steady-state γδ T cell numbers, however, appear unaffected. Strikingly, the DP αβ lineage cells that do develop in Sox13 transgenic mice are imprinted with a γδ- or precursor-like molecular profile, suggesting that SOX13 plays an active role in the lineage fate decision process or maintenance. Sox13-deficient mice, on the other hand, have selectively reduced numbers of γδ thymocytes, indicating that SOX13 is essential for proper development of γδ T cells. We present additional data demonstrating that SOX13 is a canonical WNT signaling antagonist modulating TCF1 activity, raising a strong possibility that WNT signals, and their modulators, are at the nexus of γδ versus αβ T cell lineage commitment.
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Robertson, Chadia L. "Analysis of the Role of Astrocyte Elevated Gene-1 in Normal Liver Physiology and in the Onset and Progression of Hepatocellular Carcinoma." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3573.
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First identified over a decade ago, Astrocyte Elevated Gene-1 (AEG-1) has been studied extensively due to early reports of its overexpression in various cancer cell lines. Research groups all over the globe including our own have since identified AEG-1 overexpression in cancers of diverse lineages including cancers of the liver, colon, skin, prostate, breast, lung, esophagus, neurons and neuronal glia as compared to matched normal tissue. A comprehensive and convincing body of data currently points to AEG-1 as an essential component, critical to the progression and perhaps onset of cancer. AEG-1 is a potent activator of multiple pro-tumorigenic signal transduction pathways such as mitogen-activated protein extracellular kinase (MEK)/ extracellular signal-regulated kinase (ERK), phosphotidyl-inositol-3-kinase (PI3K)/Akt/mTOR, NF-κB and Wnt/β-catenin pathway. In addition, studies show that AEG-1 not only alters
global gene and protein expression profiles, it also modulates fundamental intracellular processes, such as transcription, translation and RNA interference in cancer cells most likely by functioning as a scaffold protein.
The mechanisms by which AEG-1 is overexpressed in cancer have been studied extensively and it is clear that multiple layers of regulation including genomic amplification, transcriptional, posttranscriptional, and posttranslational controls are involved however; the mechanism by which AEG 1 itself induces its oncogenic effects is still poorly understood. Just as questions remain about the exact role of AEG-1 in carcinogenesis, very little is known about the role of AEG-1 in regulating normal physiological functions in the liver. With the help of the Massey Cancer Center Transgenic/Knockout Mouse Core, our lab has successfully created a germline-AEG-1 knockout mouse (AEG-1-/-) as a model to interrogate AEG-1 function in vivo. Here I present the insights gained from efforts to analyze this novel AEG-1-/- mouse model. Aspects of the physiological functions of AEG-1 will be covered in chapter two wherein details of the characterization of the AEG-1-/- mouse are described including the role of AEG-1 in lipid metabolism. Chapter three discusses novel discoveries about the specific role of AEG-1 in mediating hepatocarcinogenesis by modulating NF-κB, a critical inflammatory pathway.
First identified over a decade ago, Astrocyte Elevated Gene-1 (AEG-1) has been studied extensively due to early reports of its overexpression in various cancer cell lines. Research groups all over the globe including our own have since identified AEG-1 overexpression in cancers of diverse lineages including cancers of the liver, colon, skin, prostate, breast, lung, esophagus, neurons and neuronal glia as compared to matched normal tissue. A comprehensive and convincing body of data currently points to AEG-1 as an essential component, critical to the progression and perhaps onset of cancer. AEG-1 is a potent activator of multiple pro-tumorigenic signal transduction pathways such as mitogen-activated protein extracellular kinase (MEK)/ extracellular signal-regulated kinase (ERK), phosphotidyl-inositol-3-kinase (PI3K)/Akt/mTOR, NF-κB and Wnt/β-catenin pathway. In addition, studies show that AEG-1 not only alters
global gene and protein expression profiles, it also modulates fundamental intracellular processes, such as transcription, translation and RNA interference in cancer cells most likely by functioning as a scaffold protein. The mechanisms by which AEG-1 is overexpressed in cancer have been studied extensively and it is clear that multiple layers of regulation including genomic amplification, transcriptional, posttranscriptional, and posttranslational controls are involved however; the mechanism by which AEG 1 itself induces its oncogenic effects is still poorly understood. Just as questions remain about the exact role of AEG-1 in carcinogenesis, very little is known about the role of AEG-1 in regulating normal physiological functions in the liver. With the help of the Massey Cancer Center Transgenic/Knockout Mouse Core, our lab has successfully created a germline-AEG-1 knockout mouse (AEG-1-/-) as a model to interrogate AEG-1 function in vivo. Here I present the insights gained from efforts to analyze this novel AEG-1-/- mouse model. Aspects of the physiological functions of AEG-1 will be covered in chapter two wherein details of the characterization of the AEG-1-/- mouse are described including the role of AEG-1 in lipid metabolism. Chapter three discusses novel discoveries about the specific role of AEG-1 in mediating hepatocarcinogenesis by modulating NF-κB, a critical inflammatory pathway.
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Warke, Rajas V. "Molecular Dissection of the Cellular Reponse to Dengue Virus Infection." eScholarship@UMMS, 2008. https://escholarship.umassmed.edu/gsbs_diss/366.
Full textAbstract:
The immune response to viral infection involves a complexity of both innate and adaptive pathways at the cellular and the molecular level. There are many approaches to begin to define the pathways at work to control viral pathogenesis. The approach favored in this thesis was to conduct a broad screen of the innate immune response at the gene expression level of infected cells.
The innate immune response is critical to the control of viral infections. Type I interferons (IFN), IFNα and IFNβ, are antiviral proteins that are an integral part of the innate immune response. Furthermore, by virtue of their effects on maturation and activation of antigen-presenting cells, IFNs are a pivotal link between the innate and adaptive immune systems. Most cell types produce type-I IFN when exposed to viruses. However, viruses have evolved multiple strategies to suppress IFN production or signaling. It is imperative to understand the virus-host interaction at the molecular level in order to identify as yet unknown mechanisms of the host antiviral response; these additional pathways may be useful in counteracting the viral suppression of IFN. Type-I IFNs regulate expression of at least five hundred genes, suggesting a complex network of signaling pathways. Depending on the cell type different proteins regulate the induction of IFN or the expression of IFN-inducible genes. Identification of proteins that induce selected IFN-inducible genes may provide synergistic activity with or may have an advantage over type-I IFN for anti-viral therapy in the future.
Many diseases are untreatable if identified late in their progression. In resource-limited countries, many diseases are diagnosed clinically, which can lead to incorrect or delayed diagnosis and treatment. The identification of biomarkers of disease has the potential to guide the correct therapy in a timely fashion. The objective of this thesis was to identify novel anti-viral therapies and disease biomarkers for dengue virus (DENV) infection.
DENV is a mosquito-borne positive-sense single-stranded RNA virus, which causes an estimated 50 million infections annually. Most DENV infections result in a febrile illness called Dengue fever (DF). Less frequently, infections cause Dengue hemorrhagic fever (DHF), a potentially fatal vascular leakage syndrome associated with the production of pro-inflammatory cytokines. At present patients infected with DENV can only be treated by intravenous fluid support to prevent hypovolemia and hypotensive shock. This treatment is less effective in severe cases if the diagnosis is delayed. Identification of therapeutics with both antiviral and immune-modulatory activity may lower patient mortality and reduce the burden of DENV on society.
DENV infection is cleared in most individuals after a short period of viremia {Libraty, 2002 #2225}. Based on in vitro and mouse models, type-I and type-II IFN signaling pathways are thought to be critical in the regulation of DENV infection. Higher serum levels of type I and type II IFNs during acute DENV infection in patients lend support to the above hypothesis {Kurane, 1993 #2152; Libraty, 2002 #2225}.
To understand the DENV-human host cell interaction at the molecular level, we performed global gene expression analysis on DENV-infected primary human cells using Affymetrix GeneChips (HG-U133A). We studied dendritic cells (DC), monocytes, B cells and human umbilical vein endothelial cells (HUVECs), all of which are known to be permissive to DENV infection. We first identified genes commonly regulated in multiple cell types in response to DENV infection; we hypothesized that understanding this common gene expression profile would identify signaling pathways involved in regulation of viral spread, activation of immune cells or induction of inflammation. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), one of the 23 common response genes, was identified as a key link between type I and type II interferon response genes. Pretreatment of cells with recombinant TRAIL (rTRAIL) inhibited DENV replication in monocytes, B cells, HUVECs and DCs. Using the DC infection model, we showed that this inhibition of viral replication was apoptosis-independent. Type-I IFN receptor (IFNR) blocking experiments showed that signaling through the type-I IFN receptor played an important role in the antiviral activity of exogenous rTRAIL. Furthermore, TRAIL also significantly reduced the expression of mRNA and protein of pro-inflammatory cytokines (TNFα, MIP-1β and IFNα) and chemokines (MCP-2, IP-10 and IL-6) in response to DENV infection. The data that TRAIL inhibits both viral replication and pro-inflammatory cytokine production suggest that TRAIL has therapeutic value in dengue.
The endothelial cell is the site of pathology in DENV infection in vivo (vascular permeability and plasma leakage). To understand the direct effect of DENV infection on endothelial cells and its role in the induction of genes regulating vascular permeability, we compared gene expression in DENV-infected HUVECs to that of uninfected cells and cells infected with other RNA and DNA viruses, including flaviviruses (West Nile, yellow fever, and Japanese encephalitis viruses), bunyaviruses (Sin Nombre and Hantaan viruses), Epstein-Barr virus and vaccinia virus. Among the genes confirmed for their differential expression, ST2 (Interkeukin-1 receptor-like-1 protein-IL1RL1) and indoleamine 2,3-dioxygenase (IDO) were identified to be upregulated specifically in response to DENV infection. Higher serum soluble ST2 (sST2) levels were detected in DENV-infected patients than in patients with other febrile illnesses (OFI) at the end of the febrile stage and at defervescence (p=0.0088 and p=0.0004, respectively). In addition, patients with secondary DENV infections had higher serum sST2 levels compared with patients with primary DENV infections (p=0.047 at the last day of fever and p=0.030 at defervescence). Higher levels of IDO activity (pIn conclusion, global gene expression analysis identified novel proteins with promising characteristics for the treatment and/or diagnosis of DENV infection. Although further studies will be needed to validate the clinical utility of TRAIL, sST2, and IDO, these studies demonstrate the utility of this unbiased genomics approach to identify therapies to currently incurable diseases.
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Quillet, Anne. "Role des antigenes hla classe i dans la susceptibilite a la cytotoxine naturelle nk/lak." Paris 7, 1988. http://www.theses.fr/1988PA077142.
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Bukhari, Zahida. "Controle genetique de la production d'interleukine-2 chez la souris." Paris 7, 1987. http://www.theses.fr/1987PA077022.
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Malhotra, Nidhi. "Distinct Gene Circuits Control the Differentiation of Innate Versus Adaptive IL-17 Producing T Cells: A Dissertation." eScholarship@UMMS, 2012. https://escholarship.umassmed.edu/gsbs_diss/579.
Full textAbstract:
T lymphocytes are distinguished by the expression of αβ TCR or γδ TCR on their cell surface. The kinetic differences in the effector functions classifies γδ T cells as innate-like lymphocytes and αβ T cells as adaptive lymphocytes. Although distinct, αβ and γδ T cell lineages produce a common array of cytokines to mount an effective immune response against a pathogen. The production of cytokine IL-17 is a shared characteristic between the γδ T (Tγδ17) cells and the CD4 T (Th17) cells. γδ T cells develop into Tγδ17 cells in the thymus whereas CD4 T cells differentiate into Th17 cells in response to antigens in the peripheral lymphoid tissues. γδ T cells exported from the thymus, as pre-made effectors, are the early IL-17 producers compared with the late IL-17 producing Th17 cells. In this thesis we describe how TGFβ-SMAD2 dependent pathway selectively regulates Th17 cell differentiation but not Tγδ17 cells generation. We further illustrate the requirement of WNT-HMG box transcription factor (TF) signaling for the thymic programming of Tγδ17 cells.
Cytokine TGFβ in co-operation with IL-6 induces the differentiation of Th17 cells. Conversely, TGFβ signaling also regulates the differentiation and maintenance of CD4+FOXP3+ regulatory T cells. The mechanism by which TGFβ signals synergize with IL-6 to generate inflammatory versus immunosuppressive T cell subsets is unclear. TGFβ signaling activates receptor SMADs, SMAD2 and SMAD3, which associate with a variety of nuclear factors to regulate gene transcription. Defining relative contributions of distinct SMAD molecules for CD4 T cell differentiation is critical for mapping the versatile intracellular TGFβ signaling pathways that tailor TGFβ activities to the state of host interaction with pathogens. We show here that SMAD2 is essential for Th17 cell differentiation and that it acts in part by modulating the expression of IL-6R on T cells. While mice lacking SMAD2 specifically in T cells do not develop spontaneous lymphoproliferative autoimmunity, Smad2-/- T cells are impaired in their response to TGFβ in vitro and in vivo and they are more pathogenic than controls when transferred into lymphopenic mice. These results demonstrate that SMAD2 is essential for TGFβ signaling in CD4+ T effector cell differentiation and that it possesses functional capabilities distinct from SMAD3.
Although SMAD2 is essential for the differentiation of Th17 cells, TGFβ signaling via SMAD2 is not required for the thymic programming of innate Tγδ17 cells. Among different γδ T cells, Vγ2+ (V2) γδ T cells are the major IL-17 producing subsets. We demonstrate that Sry-high mobility group (HMG) box TFs regulate the development of V2 Tγδ17 cells. We show that the HMG box TF, SOX13 functions in a positive loop for the intrathymic generation of V2 Tγδ17 cells. SOX13 regulates the programming of Tγδ17 cells by controlling the expression of B-lymphoid kinase (BLK) in developing immature V2 γδ T cells. BLK is an Src-family kinase expressed by all Tγδ17 cells. Furthermore, we show another HMG box TF, TCF1, the nuclear effector of canonical WNT signaling, is the primary negative regulator of IL-17 production by all γδ T cells. We propose that the antagonism of SOX13 and TCF1 determines the generation of IL-17 producing γδ T cells. We also show that extrinsic cues from αβ T cells do not affect the generation of IL-17 producing γδ T cells. Using OP9-DL1 culture system, we demonstrate that the progenitors of V2 Tγδ17 cells are the c-Kit+ early thymic precursors.
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Equeter, Carole. "Analyse des profils d'expression génique des lymphocytes T CD4+ chez les patientes atteintes d'un cancer du sein." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210249.
Full textAbstract:
De nombreux travaux ont démontré la modulation, par les tumeurs, de certaines fonctions des cellules du système immunitaire. Dans le cadre de notre travail, nous avons étudié les lymphocytes T CD4+, cellules clefs de la réponse immune spécifique, chez des patientes atteintes d’un cancer du sein.Sur base de l’établissement des profils d’expression génique des lymphocytes T infiltrant les tumeurs, nous avons dérivé la « tumor-infiltrating CD4+ signature » (TICD4S) composée de 61 gènes immuns et qui reflète l’état d’activation immunitaire. Cette signature présente une valeur prédictive chez les patientes porteuses de tumeurs ERBB2-positives et ER-négative/PR-négative/ERBB2-négative: une plus forte expression de ces gènes est associée à une meilleure survie.
Nous avons également étudié conjointement les profils géniques établis au départ des lymphocytes T CD4+ de la tumeur, du ganglion axillaire et du sang de dix patientes. Nous avons constaté que ces profils d’expression génique des TIL CD4+ diffèrent selon le statut ER de la tumeur qu’ils infiltrent. Les lymphocytes T ganglionnaires CD4+ subissent également les effets de la masse tumorale et, tout comme les TIL, sont moins activés chez les patientes porteuses de tumeurs ER-négatives. Par contre, les lymphocytes T sanguins semblent subir dans une moindre mesure les effets de la tumeur et peu de différences ont été notées par rapport à leurs homologues isolés chez des donneuses saines.\
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Ghosh, Sreya. "Different Journeys, Same Destination: Exploring the Role of a PYHIN Protein and Involvement of Caspase-8 in the Regulation and Activation of Inflammasomes." eScholarship@UMMS, 2009. http://escholarship.umassmed.edu/gsbs_diss/928.
Full textAbstract:
Interferon-inducible PYHIN protein family includes the DNA-binding proteins, AIM2 and IFI16, which form ASC-caspase 1 dependent inflammasomes, important in immunity against cytosolic bacteria, DNA viruses and HIV. The role of other members of this family in the recognition of DNA and/or regulation of immune responses is unclear. We identified an immune regulatory function of p205, another member of the PYHIN family, in the transcriptional control of immune genes. Knockdown of p205 in macrophages revealed that inflammasome activation due to dsDNA and ligands that engage the NLRP3 inflammasome were severely compromised. Detailed mechanistic analysis showed that loss of p205 was associated with a decrease in Asc mRNA and protein levels. p205 knockdown resulted in reduced RNA Polymerase II-mediated endogenous Asc gene transcription and mRNA processing, suggesting a co-transcriptional control of Asc gene expression. Ectopically expressed p205 induced expression of an Asc gene-luciferase reporter and collaborated with other transcription factors, such as c/EBPβ, p65/RelA, to further enhance expression. p205 knockdown also affected the expression of the immune genes Cd86, Cox2, Cxcl2, Il1α, Il10, Il12α, Il6 and Ifnα in LPS-stimulated macrophages. Together these findings suggest that p205 regulates inflammation through control of Asc gene expression, and other immune genes.
Fungal infections activate both caspase 1-dependent and -independent inflammasomes. In an independent study, we show that Paracoccidioides brasiliensis fungal infection also induces caspase 8-dependent non-canonical inflammasome. Caspase 8-dependent IL-1β processing required dectin-1, Syk and Asc. Rip3-/- Casp8-/- mice infected with P. brasiliensis displayed increased fungal load and showed worse disease progression compared to wild type and Rip3-/- mice. These results revealed the importance of caspase 8 in activating and regulating inflammasome responses during fungal infection in vivo.
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Ghosh, Sreya. "Different Journeys, Same Destination: Exploring the Role of a PYHIN Protein and Involvement of Caspase-8 in the Regulation and Activation of Inflammasomes." eScholarship@UMMS, 2017. https://escholarship.umassmed.edu/gsbs_diss/928.
Full textAbstract:
Interferon-inducible PYHIN protein family includes the DNA-binding proteins, AIM2 and IFI16, which form ASC-caspase 1 dependent inflammasomes, important in immunity against cytosolic bacteria, DNA viruses and HIV. The role of other members of this family in the recognition of DNA and/or regulation of immune responses is unclear. We identified an immune regulatory function of p205, another member of the PYHIN family, in the transcriptional control of immune genes. Knockdown of p205 in macrophages revealed that inflammasome activation due to dsDNA and ligands that engage the NLRP3 inflammasome were severely compromised. Detailed mechanistic analysis showed that loss of p205 was associated with a decrease in Asc mRNA and protein levels. p205 knockdown resulted in reduced RNA Polymerase II-mediated endogenous Asc gene transcription and mRNA processing, suggesting a co-transcriptional control of Asc gene expression. Ectopically expressed p205 induced expression of an Asc gene-luciferase reporter and collaborated with other transcription factors, such as c/EBPβ, p65/RelA, to further enhance expression. p205 knockdown also affected the expression of the immune genes Cd86, Cox2, Cxcl2, Il1α, Il10, Il12α, Il6 and Ifnα in LPS-stimulated macrophages. Together these findings suggest that p205 regulates inflammation through control of Asc gene expression, and other immune genes.
Fungal infections activate both caspase 1-dependent and -independent inflammasomes. In an independent study, we show that Paracoccidioides brasiliensis fungal infection also induces caspase 8-dependent non-canonical inflammasome. Caspase 8-dependent IL-1β processing required dectin-1, Syk and Asc. Rip3-/- Casp8-/- mice infected with P. brasiliensis displayed increased fungal load and showed worse disease progression compared to wild type and Rip3-/- mice. These results revealed the importance of caspase 8 in activating and regulating inflammasome responses during fungal infection in vivo.