Dissertations / Theses: 'Primary human articular cells'

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Kohli, Nupur. "An investigation of primary human cell sources and clinical scaffolds for articular cartilage repair." Thesis, Aston University, 2016. http://publications.aston.ac.uk/28923/.

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Damage to articular cartilage of the knee can be debilitating because it lacks the capacity to repair itself and can progress to degenerative disorders such as osteoarthritis. The current gold standard for treating cartilage defects is autologous chondrocyte implantation (ACI). However, one of the major limitations of ACI is the use of chondrocytes, which dedifferentiate when grown in vitro and lose their phenotype. It is not clear whether the dedifferentiated chondrocytes can fully redifferentiate upon in vivo transplantation. Studies have suggested that undifferentiated mesenchymal stem or stromal cells (MSCs) from bone marrow (BM) and adipose tissue (AT) can undergo chondrogenic differentiation. Therefore, the main aim of this thesis was to examine BM and AT as a cell source for chondrogenesis using clinical scaffolds. Initially, freshly isolated cells were compared with culture expanded MSCs from BM and AT in Chondro-Gide®, Alpha Chondro Shield® and Hyalofast™. MSCs were shown to grow better in the three scaffolds compared to freshly isolated cells. BM MSCs in Chondro-Gide® were shown to have increased deposition of cartilage specific extracellular matrix (ECM) compared to AT MSCs. Further, this thesis has sought to examine whether CD271 selected MSCs from AT were more chondrogenic than MSCs selected on the basis of plastic adherence (PA). It was shown that CD271+MSCs may have superior chondrogenic properties in vitro and in vivo in terms of ECM deposition. The repair tissue seen after CD271+MSC transplantation combined with Alpha Chondro Shield® was also less vascularised than that seen after transplantation with PA MSCs in the same scaffold, suggesting antiangiogenic activity. Since articular cartilage is an avascular tissue, CD271+MSCs may be a better suited cell type compared to the PA MSCs. Hence, this study has increased the current understanding of how different cell-scaffold combinations may best be used to promote articular cartilage repair.

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Milella, Maria Serena. "Study of molecular mechanisms and pharmacological approaches of Alkaptonuria's disease." Doctoral thesis, Università di Siena, 2022. http://hdl.handle.net/11365/1204563.

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Alkaptonuria (AKU) is an autosomal recessive disorder, called also Black Bone Disease, for the characteristic dark coloration that some tissues and parts of the body assumed. The pathology is caused by the failure of the enzyme homogentisate 1,2- dioxygenase (HGD), that leads the accumulation of the metabolic intermediate homogentisic acid (HGA), derived by tyrosine. HGA highly reactivity triggers the formation of HGA-derived oxidized products, that react with cellular macromolecules, causing a significant generation of ROS and occurrence of oxidative stress. The ongoing oxidative stress status induces the expression of pro-inflammatory cytokines and the activation of immune cell system, with the consequently occurrence in patients of chronic inflammation and secondary AA amyloidosis. Moreover, HGA molecules bonds generate a dark polymer, called ochronotic pigment, that sticks on several organs, particularly on articular joints. Ochronosis triggers detrimental effects on tissues, as cellular death, extracellular matrix destruction, collagen fibrils rupture, since organs lose their function. Tyrosine and phenylalanine are daily taken by the body with diet, and catabolized by the HGD pathway. Thus, in AKU patients, HGA production is constant, since HGA levels in blood and urine are always elevated. Differently, the ochronotic pigment formation and deposit require more time, indeed symptoms in patients generally appear after the fourth decade of life. The rarity of AKU implies important challenges for its study. Actually, some aspects of the disease are still unexplored, despite it represents the first genetic disorder discovered that follows the principles of Mendelian recessive inheritance. In particular, one of the principal obstacles is the retrieval of AKU samples, that are scarce and generally in bad condition, for the nature of the disease. For this reason, the first step of this thesis project, described in Chapter 3, focused on the set up of in vitro model that allowed to reproduce, in a simple and cheap manner, all the characteristics of pathology. Specifically, it was set up an AKU model based on human primary chondrocytes, that allowed to study the most affected compartment in the disorder. Moreover, it was showed a preliminary study on the development of an in vivo Zebrafish model, with the objective of overcome the numerous limitations related to AKU mouse model. The aim of the present thesis work was dual: explore the molecular characteristics still unknown in AKU, and propose an innovative therapeutic approach, that could be extended to all the chronic inflammatory pathologies (Fig.1). In our lab, it was already showed that HGA administration to cells led the activation of autophagic process. Following this observation, it was explored in Chapter 4 the role of lysosomes in AKU. Indeed, is known that a dysregulation of these organelles frequently occurs in different kind of pathologies, as autoimmune or neurodegenerative disorders. Actually, an increase in lysosomes’ number had been detected in both AKU samples and model. Moreover, AKU lysosomes were localized in the periphery of cells, that represent a not physiologic conformation suggesting a decrease in their activity. Despite the ochronotic pigment deposition on cartilage and collagen fibrils was deeply studied, its formation and intracellular localization was never explicated. Thus, considering lysosomes’ role in the storage and degradation of toxic compounds, it was demonstrated in this work, for the first time, that, when cells were exposed to HGA, the ochronotic pigment was developed intracellularly and concentrated in lysosomes. Obviously, this observation could have enormous impact for the treatment of the disease and the counteraction of ochronotic pigment accumulation. Oxidative detrimental effects of HGA had been already described. Cellular macromolecules, as proteins and lipids, but also organelles, as mitochondria, undergo oxidative reactions, with the occurrence of damages often irreversible. Is known that oxidative stress and ROS target also DNA, with possible deleterious effects for cells and for all the body, considering the potential development of mutations that lead tumors onset. Thus, this aspect needs to be monitored in the progression of disorders. Therefore, the effect of HGA on the genome integrity was studied for the first time, as shown in Chapter 5. It was highlighted that HGA indirectly affected DNA, causing strand breaks and nucleolar stress. This induced the activation of repair mechanisms, on which depended cells destiny. In addition, Chapter 8 was dedicated to the study of inflammatory signal activated in AKU, a crucial characteristic of the disease. For the first time, the disorder was modeled on immune cells, in order to analyze the pattern of cytokines stimulated by HGA. It was demonstrated that the molecule was able to directly induce pro-inflammatory cytokines expression in different immune cell types. This preliminary study provides the basis for deeply understand the key issue of inflammation and immune cells activation in AKU patients. In scientific research, the molecular understanding of biological mechanisms and pathways involved in disorders results fundamental to improve their knowledge. This, beside its crucial significance, provides also the theoretical starting point for the research of possible therapeutic cure. Therefore, frequently these approaches are developed together and strictly connected. Until few years ago, AKU patients were treated only with palliative cure. Recently, EMA (European Medicines Agency) extended the application of the drug nitisinone for the treatment of AKU in adult patients. Despite this represents an important progress for the patients’ care, the drug carries some collateral effects, due to the induction of tyrosinemia, and its inability to counteract inflammation. Hence, in the present project it was studied a new therapeutic approach, described in Chapters 6 and 7, based on the combination of low-doses methotrexate (MTX), a widely used anti-inflammatory drug, with antioxidant molecules. In this way, it was obtained a formulation that combined anti-inflammatory and antioxidants properties, with a stronger effect in the counteraction of these conditions, compared to the effect of single treatments. Moreover, it was proved that the co-administration of drugs allowed to use a low concentration of MTX, with the consequent decrease of its adverse effects, and beneficial impact on patients’ health. The effectiveness of the proposed treatment was tested against typical markers of inflammation, oxidative stress and amyloidosis, proving that its application could be extended to different kind of inflammatory disorders (Chapter 6). It was also studied specifically its effect on AKU model, and demonstrated that the combination of MTX and antioxidants successfully reduced ochronotic pigment and amyloid fibrils (Chapter 7). In summary, the present thesis work gives new insight into molecular mechanisms of AKU and presented a new potential formulate for its treatment.

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Heymer, Andrea. "Chondrogenic differentiation of human mesenchymal stem cells and articular cartilage reconstruction." kostenfrei, 2008. http://www.opus-bayern.de/uni-wuerzburg/volltexte/2008/2944/.

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Ferng, Alice Shirong. "ENGINEERING ARTICULAR CARTILAGE FROM HUMAN AND CANINE NON-EMBRYONIC STEM CELLS." Thesis, The University of Arizona, 2009. http://hdl.handle.net/10150/192338.

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5

Fellows, Christopher R. "Analyses of articular cartilage-derived stem cells : identification of cellular markers for stem cells within the healthy and osteoarthritic knee articular cartilage." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/70446/.

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Previous studies have identified stem cell populations in articular cartilage using colony forming assays and mesenchymal stem cell (MSC) marker expression. The specificity of classical MSC markers for isolation of stem cells within articular cartilage is insufficient, with large and highly variable quantities being reported in the literature. This study has demonstrated, for the first time, a panel of stem cell markers specific for articular cartilage-derived stem cells (ACSC). ACSCs were isolated, quantified and cultured from healthy and OA joints. Stem cells were clonally-derived cell lines that proliferated beyond 50 population doublings whilst maintaining a phenotype, and demonstrated tri-lineage potential. We discovered that OA cartilage had a two-fold increase in stem cell number, consisting of two divergent stem cell sub-populations. These divergent populations varied in proliferative capacity with only 50% of stem cells from the OA joint capable of extended proliferation in vitro. Using transcriptomic next generation sequencing of culture-expanded chondrocytes and ACSCs we successfully identified differentially expressed genes and a panel of novel markers of cartilage-specific stem cells. Novel markers were validated using qPCR and protein labelling and, were specifically expressed in ACSCs, with no expression in the culture-expanded full-depth chondrocytes. Using immunofluorescence for novel stem cell markers we found articular cartilage-derived stem cells are localised within the transitional zone in normal cartilage and the superficial zone in OA cartilage. OA cartilage was found to contain a 2-fold increase in stem cells using immunofluorescence. Subsequently, we used the panel of novel markers and fluorescent active cell sorting to isolate a sub-population from full-depth cartilage with stem cell characteristics. These cells were plastic adherent, clonogenic, with proliferative capacity greater than 50PD and displayed tri-lineage potential, therefore meeting all criteria for classification as a MSC population. The use of specific markers to isolate ACSCs will allow for further characterisation of stem cells, including a more in-depth understanding of the mechanisms of proliferation, differentiation and degeneration within articular cartilage.

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Patel, M. "Growth of human breast cells in primary culture." Thesis, University of Glasgow, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233149.

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Lundberg, Anna Maria Cecilia. "Investigation of TLR signalling pathways in human primary cells." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425006.

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8

McManus, Lindsay L. "A study of human mesenchymal stem cells, human primary osteoblasts and osteoblast-like cells using Raman spectroscopy." Thesis, University of Ulster, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.551188.

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Raman spectroscopy is a vibrational spectroscopy technique that provides a global biochemical signature and has been shown to have utility in the analysis of biological cells for bone tissue engineering applications. Traditionally, sample analysis in this field employs destructive biological methods that require the use of biomarkers, however, Raman has since become an essential tool in various areas of bio-industry and by incorporating the technique into biological laboratories these perturbing methodologies are no longer the only means of analysis. Therefore the focus of this study was to investigate the capability of Raman spectroscopy as a tool for the in vitro characterisation of the sub-cellular composition and osteogenic potential of human mesenchymal stem cells. As with most biological samples a high degree of heterogeneity is often found, therefore in order to extract the desired information from the biological studies multivariate analysis tools were utilised. The reliability and consistency of the vibrational analysis was confirmed by means of comparison with current gold-standard techniques such as, alizarin red staining, real-time polymerase chain reaction and immunocytochemistry. A further novelty was introduced with the use of Raman spectroscopy to determine the suitability of the U20S osteoblast-like cell line for use as a model for human primary osteoblasts with emphasis on the ability of these cell types to replicate their tissue of origin. Investigation of the U20S osteoblast-like cell line provided evidence of dense multilayered mineralised regions that corresponded more closely to native bone, which has not been previously reported on. This finding contradicts previous reports on U20S osteoblast-like cells which have consistently been described as non-osteoinductive. When Raman spectroscopy is coupled with biological and multivariate analyses techniques, it shows further novelty when employed to monitor mineralisation of human mesenchymal stem cells, human primary osteoblasts and osteoblast-like cells. This body of work culminates the success of a truly multidisciplinary approach and provides the potential for further work on bone cell analysis and the applications of spectroscopy for biological studies and bone tissue engineering applications.

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9

Beale, Gary S. "Evaluation of PKC isozyme expression, overexpression and antinsense-suppression in C6 glioma cells and primary articular chondrocytes." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310916.

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Alsayegh, Khaled. "Characterizing the Role of CDK2AP1 in Primary Human Fibroblasts and Human Embryonic Stem Cells." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/537.

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Cyclin Dependent Kinase-2 Associated Protein-1 (CDK2AP1) plays an important role in cell cycle regulation, by inhibiting CDK2 and by targeting it for proteolysis. It is also known to bind the DNA polymerase alpha-primase complex and regulate the initiation step of DNA synthesis. Its overexpression has been shown to inhibit growth, reduce invasion and increase apoptosis in a number of cancer cell lines. In studies in which mouse embryonic stem cells (mESCs) with targeted deletion of the Cdk2ap1 gene were used, Cdk2ap1 was shown to be required for epigenetic silencing of Oct4 during differentiation. The goal of this thesis was to examine the role of CDK2AP1 in somatic cells (primary human dermal fibroblasts (HDFs)) and human embryonic stem cells (hESCs) and specifically assess its impact on proliferation, self-renewal and differentiation. In the first part of this study, using a short-hairpin RNA (shRNA) approach, we investigated the effect of CDK2AP1 downregulation in HDFs. Outcomes indicated: (a) reduced proliferation, (b) premature senescence, (c) cell cycle alterations, (d) DNA damage, and (e) an increase in p53, p21, and the p53-responsive apoptotic genes BAX and PUMA. Simultaneous downregulation of p53 and CDK2AP1 in HDFs confirmed that observed phenotype was p53 dependent. In the second part of this study, using a shRNA approach, we investigated the role of CDK2AP1 on hESC fate associated with self-renewal and differentiation. We found that CDK2AP1 knockdown in hESCs resulted in: (a) reduced self-renewal (b) enhanced differentiation (c) cell cycle alterations and (d) increase in p53 expression. Results indicate that the knockdown of CDK2AP1 in hESCs enhances differentiation and favors it over a self-renewal fate. Thus, this study has successfully identified novel functions for CDK2AP1, as its knockdown has a significant impact on self-renewal, differentiation and senescence. Results obtained from this study could contribute to development of directed differentiation strategies for generating uniform populations of differentiated phenotypes from hESCs for clinical applications.

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Jones, Nancy. "Glycosaminoglycan synthesis by normal human mammary epithelial cells in primary culture." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/25903.

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The extracellular matrix (ECM) influences cell growth and differentiation. Glycosaminoglycans (GAGs), alone or complexed with protein (proteoglycans), are a major component of the ECM affecting cell behavior. GAG synthesis has been studied extensively in animal models and malignant cells. This research centres on studying GAG production by normal human mammary epithelial cells in culture. Mammary tissue obtained from reduction mammoplasties were dissociated to single cells. The epithelial cell population was seeded onto hydrated collagen gels at 2-2.5x10⁵ cells/cm² in medium containing 5% FCS and 5μg/ml of insulin. Ultrastructural studies confirmed the epithelial nature of the cultures. To measure GAG synthesis, cultures were incubated with ³H-glucosamine for 24 hours at 3 time points; days 3-4, 9-11 and 17-18. The cultures were proliferating at the early time point and had reached a stationary phase at the later time points. Cell, ECM and medium fractions were analyzed for GAGs as identified by enzyme degradation and cellulose acetate electrophoresis. At day 4, when cells were actively growing, the majority of GAGs produced were released into the medium fraction (75-80%). The predominant GAG was the nonsulfated GAG, hyaluronic acid (HA). Of the sulfated GAGs chondroitin sulfate (CS) 4 and 6 comprised only 18% of total GAGs; dermatan sulfate (DS) synthesis was negligible. At the later time periods, when cultures had ceased growing a higher percentage of total GAG was incorporated into an ECM (50-65%). The sulfated GAGs were preferentially incorporated into the ECM, CS 4 and 6 comprising 70% and DS comprising 30%. The marked difference in type and location of GAGs produced was not merely a function of time in culture. Cultures seeded at high densities (5x10⁵ cells/cm²) were not proliferating when terminated at day 4. Their GAG profile was similar to that of lower density cultures at day 10. This data provides a baseline from which we can determine if cell-synthesized GAGs, play a role in maintaining differentiated and malignant phenotypes.
Medicine, Faculty of
Graduate

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Varandas, Edna Soraia Gregório Ribeiro Varandas. "Low-dose effects of Bisphenol A on human primary vascular endothelial cells and colon cancer cells." Doctoral thesis, ISA/UL, 2014. http://hdl.handle.net/10400.5/7338.

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Doutoramento em Biologia - Instituto Superior de Agronomia
Bisphenol A (BPA) is an extensively utilized endocrine disruptor for which human exposure is considered generalized through ingestion. Information regarding BPA effects on vascular and digestive tract tissues is scarce. Therefore, in this work primary Human Umbilical Vein Endothelial Cells (HUVEC) and human colon adenocarcinona cell line HT29 were used to evaluate BPA effects at two distinct low-dose concentrations relevant in terms of human health risk assessment. BPA differentially affects the cell types studied, with more pronounced aneugenic effects, nucleolar disruption and transcriptional deregulation observed in HUVEC. Prolonged BPA exposure affects aging processes in senescent HUVEC. Interaction experiments involving expression of key cancer related genes shows that BPA antagonizes transcriptional effects of the chemotherapeutic agent doxorubicin in HT29. Additionally BPA aneugenic effects are enhanced by co-exposure with Eupatorium cannabinum L. ethanolic extract, a medicinal plant, for which a potent cytotoxic activity against HT29 cells is also demonstrated here. Altogether these results support increasing concerns regarding harmful effects of BPA at low-dose on human health and draw attention to the importance of a deeper understanding of BPA potential interactions with other chemicals.

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13

Kothari, Manish. "Purification and characterisation of malignant epithelial cells from human primary breast cancers." Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444603.

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14

Kakal, Juzer. "Transcriptional regulation of the CD127 gene in primary human CD8 T-cells." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28090.

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Factors regulating expression of the IL-7 receptor throughout the CD8 T-cell life-span have not been fully characterized but IL-7 has been shown to down regulate the IL-7 receptor alpha-chain (CD127) at the cell surface. Here we show that IL-7 induced a decline in the level of total CD127 transcripts in CD8 T-cells. Also, IL-7 had no effect on CD127 mRNA stability, or alternative splicing. We also find that down regulation of CD127 by IL-7 requires de novo transcript and protein synthesis. Reporter assay analysis of the CD127 promoter showed that sequences up to 3kb upstream of the TATA box are required for basal CD127 gene expression. Within this region a Glucocorticoid Response Element near -2.2kb was identified as an important regulator of CD127 transcription. Conversely, IL-7 did not down regulate the ∼3kb promoter construct suggesting that the IL-7 responsive elements may lie outside this region.

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15

Chan, Michelle Tsz Ting. "Regulation of primary, immortalized, and metatstatic human pancreatic ductal cells by insulin." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43770.

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Epidemiological studies have reported positive correlation between type 2 diabetes and risk of pancreatic cancer. Hyperinsulinemia occurring during early diabetes has been postulated to be a possible pathophysiological mechanism in promoting pancreatic cancer, but the mechanisms by which elevated insulin levels contribute to pancreatic carcinogenesis are still unknown. Here, the effects of insulin and its associated mechanism on cellular viability were examined in three cell models that are meant to represent three stages in pancreatic cancer progression. Furthermore, using small molecule inhibitors, the role of RAF/ERK pathway and PI3K/AKT pathway on cellular viability were also compared across three cell models. Different stages of pancreatic cancer progression were modeled in vitro with primary human pancreatic ductal cells, an immortalized pre-malignant human pancreatic ductal cell line (HPDE), and an advanced metastatic human pancreatic adenocarcinoma cell line (PANC1). All cell types were serum starved and treated with insulin, IGF1, or small molecule inhibitors targeting RAF1, MEK, AKT, or PI3K, then subjected to cell viability assays, cell death assays, and Western blot analysis for ERK and AKT activation. We observed that cell viability was promoted by exogenous insulin in PANC1 cells, and not in primary cells. In PANC1 cells, the insulin-mediated enhancement of cell viability was associated with sustained AKT activation. Furthermore, insulin-mediated reduction in cell death was not observed. When comparing the roles of RAF/ERK and PI3K/AKT pathways on cell viability, we observed an increase in cell death in primary cells when AKT was inhibited. In contrast, cell death was induced in HPDE and PANC1 cells when the RAF1 or MEK were inhibited. If extrapolated, the data suggest that hyperinsulinemia may not play a role in initiating pancreatic cancer, but high levels of insulin may accelerate the cancer progression.

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Crossland, Katherine Louise. "Characterisation of a novel transmembrane protein in primary human CD4+ T-cells." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2573.

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There are two main mechanisms of tolerance, one in the thymus and one in the periphery. Anergy, a peripheral mechanism, is a state of hypo-responsiveness where T-cells fail to respond to antigenic stimulus. A breakdown in immunological self-tolerance leads to autoimmunity and so provides an exciting research area for therapeutic intervention in autoimmune disease. Differential display studies comparing anergic and activated CD4+ T-cells identified claudin domain containing protein 1 (CLDND1) to be differentially expressed between these two states. In addition, preliminary experiments performed in our lab identified CLDND1 as a potential negative regulator of CD4+ T-cell activation. The aim of this study was to identify the role of CLDND1 in CD4+ T-cells. Antibodies against CLDND1 were raised and validated before use to determine CLDND1 expression in immune cell subsets and during T-cell activation. The function of CLDND1 in T-cells was investigated using gene silencing or over-expression techniques. CLDND1 expression was also sought in the autoimmune disease, rheumatoid arthritis (RA), to identify whether CLDND1 may be involved in disease pathogenesis. Antibodies were successfully raised against CLDND1 and CLDND1 was found to be transiently up-regulated during CD4+ T-cell activation. CLDND1 gene silencing attempts, while successful at the RNA level, did not translate to a reduction in CLDND1 protein, suggesting CLDND1 may be regulated independently of gene transcription. Over-expression studies were consistent with CLDND1 being a negative regulator of T-cell proliferation or an inducer of cell death, depending on the activating stimulus used. CLDND1 expression was found to correlate with rheumatoid factor (RF) status in early RA patients and may suggest a role for CLDND1 in the disease setting. Some findings identify similarities between CLDND1 and other proteins, providing links for functional pathways and a plethora of further avenues of research.

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Zielecki, Julia. "Establishment of in vitro-infection models for Chlamydia trachomatis based on human primary cells and primary tissue." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://dx.doi.org/10.18452/16405.

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Zellkultursysteme mit Krebszelllinien werden seit Langem zur Untersuchung der Interakti-on zwischen Pathogenen und ihren Wirtszellen eingesetzt. Diese Systeme eignen sich aufgrund der reduzierten Komplexität für die Analyse einzelner Faktoren, spiegeln jedoch nicht den Zustand primärer Zellen oder die komplexe Gewebestruktur wieder. Um die Beschränkungen zu umgehen, wurden in dieser Arbeit neue Modelle etabliert auf der Grundlage von reversibel immortalisierten humanen Primärzellen und ex vivo Kultur von intaktem humanem Eileitergewebe. Infektionen mit dem humanpathogenen Bakterium Chlamydia trachomatis, welches chronische Schmerzen oder Unfruchtbarkeit auslösen kann, wurden in diesen Modellen untersucht. Reversible Immortalisierung wurde mit pri-mären human Eileiterzellen (FT Zellen) und humanen Nabelschnurzellen (HUVEC) durchgeführt. Das System basiert auf lentiviralem Gentransfer und dem Cre-lox-System. HUVEC Zellen wurden mit Kombinationen der Onkoproteine hTERT, SV40T und Bmi1 immortalisiert. Immortalisierung von FT Zellen wurde mit SV40T und Bmi1 erreicht. Eine Analyse der FT Zelllinien zeigte Veränderungen des Karyotyps durch die Immortalisie-rung. Bemerkenswerterweise konnten die Stammzellmarker CD44 und Oct4 in FT Zellen nachgewiesen werden. Ex vivo Gewebekultur humaner Eileiter wurde als stabiles Infekti-onsmodel für Chlamydia trachomatis etabliert. Mittels hochauflösender Konfokal-mikroskopie wurde gezeigt, dass die Infektion mit C. trachomatis tiefgreifende Verände-rungen im Epithel der Mukosa auslöst und zum Verlust der Zelladhäsion und Zellpolarität führt. Ein erhöhter Anteil apoptotischer Zellen wurde nach Infektion mit Serovar D beo-bachtet, einem klinischen Isolat des Genitaltraktes. Dieses Ergebnis steht im Gegensatz zu Infektionen mit dem Laborstamm Serovar L2. Phänotypische Veränderungen in nicht infizierten Zellen weisen auf die Existenz parakriner Signalwege während der akuten In-fektion und Veränderung der epithelialen Homeostase hin.
Cell culture systems with cancer-derived cell lines have long been used to study the interaction between pathogens and their host cells. Due to reduced complexity these systems are convenient for the analysis of single factors; however, they do not represent the condition of primary cells or the complex tissue structure. To circumvent these limitations new models were established in this study on the basis of reversibly immortalized human primary cells and ex vivo culture of intact human fallopian tube tissue. Infections with the human pathogenic bacterium Chlamydia trachomatis, which can lead to chronic pain or infertility, were analyzed in these models. Reversible immortalization was applied to primary human fallopian tube (FT) cells and human umbilical vein cells (HUVEC). This system is based on lentiviral gene transfer and the Cre-lox-system. HUVEC cells were immortalized with a combination of two of the oncoproteins hTERT, SV40T and Bmi1. Immortalization of FT cells was achieved with SV40T and Bmi1. Analysis of FT cell lines revealed changes of the karyotype induced by immortalization. Remarkably, the stem cell markers CD44 and Oct4 were detected in FT cells. Ex vivo tissue culture of human fallopian tubes was established as stable and reliable infection model for Chlamydia trachomatis. Via high resolution confocal analysis the infection with C. trachomatis was discovered to trigger profound changes in the epithelial mucosa, causing loss of cell adhesion and polarity. Interestingly, an increase in the rate of apoptotic cells was observed after infection with serovar D, a clinical genital tract isolate. This finding is in contrast to infections with serovar L2, a laboratory strain. Phenotypic changes in non-infected cells suggest the existence of paracrine signalling during acute infection and change in epithelial homeostasis.

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Nelli, Rahul Kumar. "Molecular host response to influenza virus infections in primary pig and human cells." Thesis, University of Nottingham, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.595851.

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Conventional swine and human influenza viruses are usually not life threatening in their respective host. However the outcomes of highly pathogenic avian influenza (HPAI) H5Nl infections in humans (-60% mortality, WHO, 2011) and pigs (mild or absent; Nidom, 2010) are in sharp contrast. To investigate the biological basis of resistance in pigs to highly pathogenic avian H5Nl infections, we examined the host receptor distribution for virus binding, which could provide valuable comparative information of virus affinity between pigs and humans. A major determinant of influenza infection is the presence of virus receptors on susceptible host cells to which the viral haemagglutinin is able to bind. Avian viruses preferentially bind to sialic acid 0.2, 3-galactose (SAa2, 3- Gal) linked receptors, whereas human strains bind to sialic acid a2, 6-galactose (SAa2, 6-Gal) linked receptors. The relative expression and spati al distribution of SAa2, 3-Gal and SAa2, 6-Gal receptors in the major organs of pigs were examined, by lectin histochemistry.

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Schuster, Susanne, and Antje Garten. "Resveratrol Differentially Regulates NAMPT and SIRT1 in Hepatocarcinoma Cells and Primary Human Hepatocytes." Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-142581.

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Resveratrol is reported to possess chemotherapeutic properties in several cancers. In this study, we wanted to investigate the molecular mechanisms of resveratrol-induced cell cycle arrest and apoptosis as well as the impact of resveratrol on NAMPT and SIRT1 protein function and asked whether there are differences in hepatocarcinoma cells (HepG2, Hep3B cells) and non-cancerous primary human hepatocytes. We found a lower basal NAMPT mRNA and protein expression in hepatocarcinoma cells compared to primary hepatocytes. In contrast, SIRT1 was significantly higher expressed in hepatocarcinoma cells than in primary hepatocytes. Resveratrol induced cell cycle arrest in the S- and G2/M- phase and apoptosis was mediated by activation of p53 and caspase-3 in HepG2 cells. In contrast to primary hepatocytes, resveratrol treated HepG2 cells showed a reduction of NAMPT enzymatic activity and increased p53 acetylation (K382). Resveratrol induced NAMPT release from HepG2 cells which was associated with increased NAMPT mRNA expression. This effect was absent in primary hepatocytes where resveratrol was shown to function as NAMPT and SIRT1 activator. SIRT1 inhibition by EX527 resembled resveratrol effects on HepG2 cells. Furthermore, a SIRT1 overexpression significantly decreased both p53 hyperacetylation and resveratrol-induced NAMPT release as well as S-phase arrest in HepG2 cells. We could show that NAMPT and SIRT1 are differentially regulated by resveratrol in hepatocarcinoma cells and primary hepatocytes and that resveratrol did not act as a SIRT1 activator in hepatocarcinoma cells.

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20

Filippis, Christodoulos [Verfasser]. "PD-1 checkpoint inhibition in Leishmania infection of primary human cells / Christodoulos Filippis." Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2018. http://d-nb.info/1225484898/34.

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21

Kruschinski, Anna [Verfasser]. "Engineering antigen-specific primary human NK cells against HER-2 positive carcinomas / Anna Kruschinski." Berlin : Freie Universität Berlin, 2011. http://d-nb.info/1025489705/34.

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Sessions, John W. "In Vitro Molecular Modification of Human Cultured and Primary Cells Using Lance Array Nanoinjection." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/5859.

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Fundamentally altering cellular function at a genetic level is a major area of interest in the biologic sciences and the medical community. By engineering transfectable constructs that can be inserted to dysfunctional cellular systems, scientists can mitigate aberrant genetic behavior to produce proper molecular function. While viral vectors have been a mainstay in the past, there are many limitations, particularly related to safety, that have changed the focus of genome editing to incorporate alternative methods for gene delivery. Lance Array Nanoinjection (LAN), a second-generation microfabricated transfection biotechnology, is one of these alternative technologies. LAN works by utilizing both simultaneous electrostatic interaction with molecular loads and physical lancing of hundreds of thousands of target cell membranes. The purpose of this work is to demonstrate LAN in the context of in vitro transfection of immortalized culture cells and primary cells. As part of that exploration, three distinct areas of investigation are considered, which include: characterizing environmental factors that impact LAN transfection, demonstrating LAN genetic modification of immortalized HeLa 229 culture cells using an indicator marker, and lastly, investigating the effects of LAN on human primary, neonatal fibroblasts.

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Music, Ena. "Optimisation of methods for driving Chondrogenesis of human and ovine bone marrow–derived stromal cells." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/207820/1/Ena_Music_Thesis.pdf.

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This thesis investigated the effects of different molecules and oxygen levels on the quality of engineered cartilage tissues produced using both human and sheep bone marrow–derived stromal cells. As damaged cartilage cannot repair naturally, it is hoped that cell-based repair strategies can delay the need for joint replacement surgery due to osteoarthritis, which affects 1 in 10 Australians.

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Kroeker, Andrea. "A proteomic approach to discovering novel anti-influenza mechanisms in primary human airway epithelial cells." Journal of Proteomic Research, 2012. http://hdl.handle.net/1993/30400.

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The influenza virus has a large impact on global health; however, it is difficult to formulate vaccines and influenza therapies that are effective against influenza. The influenza virus mutates rapidly, has the ability to emerge as novel strains with pandemic potential and can quickly become resistant to any given drug. Therefore, the generation of novel anti-influenza therapeutics that are effective against multiple strains would be highly beneficial. To date, the majority of anti-influenza research has focused on targeting specific components of the virus in order to interfere with its replication. However, it has been proposed that host proteins and signaling pathways may be essential components to viral replication and could also become novel anti-influenza drug targets. Therefore, this study utilized a large proteomic screen to identify host proteins that were up- and down-regulated in response to influenza infection. Collectively, these proteins clustered into five specific cell pathways and processes including interferon signaling, purine metabolism, cell death, ubiquitin-like signaling and mitochondrial oxidoreductases. Overall, this project identified potential novel anti-influenza targets in primary airway epithelial cells.
May 2015

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Yost, Arla June. "Development and application of an in vitro culture model for primary human T-ALL cells." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/41988.

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T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy that affects both children and adults. Optimization of chemotherapy regimens has led to steady improvements in outcome for pediatric patients over the last 5 decades, with a long-term survival rate of 80%. However, the five-year survival rate for adults is still only 35-40% and there is a poor prognosis for relapse patients (Goldstone et al., 2008). Further improvements in outcome will undoubtedly require introduction of novel approaches and more specific targeted therapies. Research efforts in this area have been hampered by the lack of a reproducible model for in vitro growth of human T-ALL blasts. Most efforts to date have relied heavily upon established cell lines, which can be a useful tool to study malignancies but do not necessarily always represent bona fide disease biology, and in vivo studies involving patient samples expanded as xenografts in immunocompromised mice, which are costly, time-consuming and complicated by non-cell autonomous effects. Current methods for in vitro culture of patient T-ALL samples yield variable performance with high rates of apoptosis and less than robust proliferation. Development of an efficient and reproducible in vitro culture method for growth of primary human T-ALL blasts would greatly enhance the ability to test and validate novel therapies by allowing for direct assay for sensitivity/resistance of patient cells which have not been subject to extensive manipulation or selection. In this work we report an in vitro co-culture system using defined, serum-free media and a stromal feeder cell layer which supports robust growth and minimal apoptosis of patient T-ALL blasts. We have shown that the stromal feeder cell layer and supplemental IL-7 cytokine is critical for sustained patient T-ALL blast growth in this model. Finally, we have demonstrated the utility of this culture system as a platform that will facilitate ongoing efforts to identify growth factors/cytokines required for maintenance of leukemia cell self-renewal activity, aid in the study of signaling pathways important in T-ALL pathogenesis and maintenance, and allow for prospective testing of novel compounds for therapeutic efficacy on patients’ own tumor cells, thus enabling implementation of personalized medicine initiatives.

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DeGrace, Marciela. "RNAi Screens in Primary Human Lung Cells Reveal Hermansky-Pudlak Syndrome Proteins as Influenza Suppressors." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10152.

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Influenza is an important human pathogen that causes fatal disease in 250,000-500,000 people worldwide each year. Because of high levels of variation between influenza strains, vaccines are not always effective and must be administered annually. Influenza virus, which replicates primarily in the lung epithelium, encodes only 10 proteins and relies heavily on host products to replicate. Determining which cellular factors are important for influenza replication represents an important area of virology and cellular biology research, and could elucidate proteins or pathways to target for antiviral therapies. We developed a high throughput screening method in primary human bronchial epithelium (HBECs) to identify novel regulators of influenza replication. We first used this method to functionally examine 1745 genes that were identified as potential influenza regulators due to transcriptional regulation by virus or viral products, direct interaction with viral proteins via yeast two-hybrid, or through computational analysis. This screen confirmed some known regulators of influenza replication while identifying novel viral interactors as influenza regulators (e.g. USHBP1, ZMAT4). We also found that the WNT, p53, and ER stress pathways, among others, affect viral replication and interferon production. The life cycle of influenza involves extensive intracellular trafficking of viral components. We again used RNAi to systematically examine the roles of vesicle, RNA, and protein trafficking genes in the production of infectious influenza A virus in primary lung cells. Among the factors that significantly impact viral infection, we identify a set of five genes with strong antiviral effects that are mutated in patients with Hermansky-Pudlak syndrome (HPS). Depletion of HPS genes leads to elevated viral RNA at an early stage of influenza infection prior to transcription. In contrast, depletion of these genes does not alter the innate immune response to virus or interferon. Using an HPS-1 patient cell line, we find an increase in viral fusion to endosomal compartments but no change in viral binding to the cell surface or entry into the early endosome. Our studies uncover a potential role for many trafficking factors in the influenza life cycle, and point to an HPS1-dependent process that inhibits viral entry prior to viral membrane fusion.

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Singh, Vikramjeet [Verfasser]. "Effects of cladribine on primary rat microglia and human monocyte-derived dendritic cells / Vikramjeet Singh." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2013. http://d-nb.info/1030453098/34.

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Makino, Seiko. "Investigation of expression quantitative trait loci and regulatory genetic variants in primary human immune cells." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:67d0c1e8-c6f1-4ca7-a311-52f20b79128b.

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The post human genome sequence era has begun to explore various aspects of the functional genome in relation to disease including gene expression, genetic variation and epigenetics. The genetic determinants of common and complex phenotypes are difficult to resolve even though their heritability is recognised. Recent genome-wide association studies (GWAS) for common diseases has identified many new disease susceptibility associated loci. These loci often lie in non-coding regions of the genome and disease associated genetic variants are proposed to act by modulating gene expression. This thesis investigated genetic variation as determinants of gene expression in the context of the immune system especially focused on the innate immune and inflammatory responses. Different primary human immune cell types were collected from healthy volunteers of European ancestry to achieve this. In order to identify genetic variants associating with gene expression, expression quantitative trait loci (eQTL) mapping was conducted in a cell type specific manner. The primary dataset (n=288) consists of CD19⁺ B-cells from the adaptive immune system and CD14⁺ monocytes from the innate immune system. 78% of the total cis eQTL were found to be cell type specific and include genes relating to their roles in the immune response. Trans eQTL showed greater cell type specificity and include master regulatory eQTL on the LYZ locus at chromosome 12q15 in monocytes and the KLF4 (9p31) in B-cells. The identified eQTL are implicated in association with autoimmune disease susceptibility including inflammatory bowel disease, diabetes and rheumatoid arthritis. The second analysed dataset (n=64) consists of CD14+ monocytes and macrophages differentiated ex vivo. Macrophages are involved in many inflammatory diseases as well as in the innate immune response. The differential gene expression and eQTL mapping analyses were conducted to investigate macrophages specific gene expression signatures and associations to genetic variants. Macrophage eQTL are involved in signal transduction for the inflammatory response (IL1RN and STAT4) and lipid metabolism (PPARG) with implication for metabolic disease association. The eQTL analyses using primary immune cell types provide insights into genetic variation in association to gene expression which is involved in autoimmunity and disease susceptibility.

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Burger, Katharina [Verfasser]. "Influence of different noxa on DNA repair capacity of primary human skin cells / Katharina Burger." Konstanz : Bibliothek der Universität Konstanz, 2011. http://d-nb.info/1017360456/34.

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Pickering, Curtis Reid. "Understanding the early events in breast carcinogenesis by inactivating p16INK4a in primary human mammary epithelial cells." Diss., Search in ProQuest Dissertations & Theses. UC Only, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3324574.

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Donà, Gabriella. "Human red blood cells alterations in Primary Aldosteronism: Mineralocorticoid Receptor (MR) involvement in the Aldosterone pathway." Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3423923.

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Red blood cells (RBCs) are a-nucleated cells particularly exposed to different stimuli, among which circulating hormones and intra/extra-cellular derivatives from oxidization processes. In addition, our previous studies showed that in the case of inflammatory diseases with GSH content alterations, RBCs were much more sensitive to diamide, a mild oxidant able to trigger tyrosine-phosphorylation (Tyr-P) of membrane proteins, mainly band 3. Aldosterone (Aldo), mineralocorticoid hormone, has been shown to induce many effects other than the common diuretic process regulation and involving the expression and activation of the superoxide generating enzyme NADPH oxidase, thus potentially explaining the increased plasma markers of oxidative stress (OS) like isoprostanes in primary aldosteronism (PA), disease characterized by excessive Aldo secretion. This well-known Aldo action is mediated by the activation of a cytosolic specific receptor, the mineralocorticoid receptor (MR), in the so called genomic pathway, which distinguishes from the direct effect of Aldo on many proteins and enzymes in the second mechanism, also known as non-genomic pathway. Starting from these evidences, if a direct Aldo involvement in the triggering of inflammatory-related oxidative status of the cells was evolving, RBCs were the eligible cells for the investigation of the non-genomic Aldo pathway. The study involved PA patients and healthy control (HC) and consisted with three phases: i) a first approach was carried out to evidence potential alterations in PA RBCs followed by an in vitro deepening to assess the effective direct/indirect involvement of Aldo in these alterations; ii) once identified as responsible of the RBCs alterations found in PA, Aldo pathway within HC RBCs cytosol was investigated; iii) at last, Aldo-related pathway in RBCs was studied with particular attention to the mechanism leading to membrane band 3 alterations starting from Aldo induced receptor activation. In the first part, PA RBCs were showed to have oxidative-like alterations such as band 3 protein increase of both Tyr-P level and clustering, thus suggesting that PA could be linked to other inflammatory diseases. The effects of Aldo, cortisol (Cort) and canrenone (Can) (added as agonist and inhibitor, respectively) were compared and Aldo was confirmed as the only responsible of the alterations previously observed in PA RBCs. Furthermore, Aldo was shown to trigger RBCs membrane alterations leading to autologous IgG binding in a sort of premature ageing of the cells. The second part of the study analyzed the mechanism of Aldo action: for the first time MR was identified in RBCs cytosol as a soluble multi-protein complex, differently regulated by the effector utilized. In facts, in the presence of Aldo, MR broke away from the complex to form dimers which were promptly proteolysed in a sort of turn off signaling. Can or Cort were not able to trigger similar events, thus explaining the different alterations found on RBCs membranes. However, since to now no direct evidence was found about the possibility that Aldo induced an increase of oxidation status in RBCs, oxidization level in both membranes and cytosol was addressed in the third and last part of the study. Results showed no difference in GSH and GSSP contents and carbonic anhydrase (CA) monomerization and activity between HC and PA RBCs. In contrast, preliminary data would confirm a sort of oxidative-related increase of band 3 disulfide bond formation, thus suggesting a new intriguing mechanism leading to band 3 increased oxidative status without changing the common anti-oxidative cellular defenses. Further investigations addressing this mechanism are in progress. In conclusion, we found that in PA RBCs Aldo is responsible for the membrane alterations leading to a potential premature removal of the cells from circulation. Aldo exerts its effect through the activation of the soluble MR complex, which participates in the modulation of the Aldo signaling through the possibility of being differently affected by other steroids or Aldo inhibitors (Can). Further studies are in progress to explore both nature and potential mediators of the Aldo-induced alterations in the band 3 dimer formation.
Gli eritrociti (RBCs) sono cellule non nucleate particolarmente esposte a differenti stimoli, tra i quali l’effetto degli ormoni circolanti nel sangue e i derivati dei processi di ossidazione intra o extracellulari. Studi precedenti condotti nel nostro laboratorio hanno dimostrato che, nel caso di malattie infiammatorie con alterazione del contenuto di GSH rispetto ai controlli, gli eritrociti erano molto più sensibili alla diamide, un blando ossidante in grado di innescare la tirosin-fosforilazione (Tyr-P) delle proteine di membrana, principalmente della proteina banda 3. L’aldosterone (Aldo), ormone mineralocorticoide, oltre alla sua classica azione regolatoria dei processi diuretici, è in grado di indurre molti altri effetti tra i quali l’espressione e l’attivazione dell’enzima NADPH ossidasi, generatore di anione superossido. Questo fatto potrebbe potenzialmente spiegare l’incremento di marker plasmatici di stress ossidativo (OS) come gli isoprostani, nell’aldosteronismo primitivo (PA), patologia caratterizzata da un’eccessiva secrezione di Aldo. Partendo da queste evidenze, gli RBCs erano cellule ottimali per studiare se l’Aldo potesse indurre un aumentato stato di ossidazione determinato da una sua azione diretta sui processi infiammatori. Infatti, in queste cellule non nucleate, un eventuale coinvolgimento dell’Aldo nei meccanismi infiammatori, mediante un’azione non-genomica, sarebbe stato univocamente dimostrato. Lo studio ha coinvolto sia pazienti con PA che controlli sani (HC) e si è svolto in tre fasi: i) in un approccio iniziale abbiamo valutato se esistessero potenziali alterazioni negli RBCs dei pazienti, procedendo, poi, con un approfondimento in vitro condotto sugli RBCs di HC per confermare o meno un diretto coinvolgimento dell’Aldo nell’indurre queste alterazioni; ii) una volta identificato come responsabile effettivo delle alterazioni riscontrate, abbiamo cercato di chiarire il meccanismo di azione dell’Aldo a livello citosolico; iii) infine, partendo dall’evidenza che l’azione dell’Aldo veniva mediata dall’attivazione del recettore citosolico, abbiamo cercato di capire il meccanismo attraverso cui questa attivazione si trasmettesse, a livello delle membrane. Nella prima parte, abbiano dimostrato che negli RBCs dei pazienti erano presenti delle alterazioni quali un incremento sia della Tyr-P della banda 3 che una sua aggregazione, suggerendo, così, che la patologia potesse essere correlata ad uno stress ossidativo come dimostrato in altre malattie infiammatorie. Inoltre, dopo aver comparato gli effetti di Aldo, cortisolo (Cort) e canrenone (Can) (aggiunti rispettivamente come agonista ed inibitore), abbiamo confermato che era proprio l’Aldo il diretto responsabile delle alterazione che, in ultima, portavano ad un aumento della quantità degli anticorpi autologhi legati alla membrana, rispecchiando una prematuro invecchiamento cellulare. Nella seconda parte dello studio, abbiamo dimostrato, per la prima volta, la presenza a livello citosolico del recettore dei mineralocorticoidi (MR), che risulta essere presente in un complesso multi-proteico di elevato peso molecolare. Inoltre, abbiamo evidenziato come solo l’Aldo inducesse la liberazione dell’MR dal complesso a formare dimeri prontamente proteolizzati in una sorta di spegnimento del segnale. Al contrario, né Cort né Can erano in grado di indurre l’attivazione del recettore. Tuttavia, poiché finora non è mai stato dimostrato se l’Aldo potesse indurre un aumento delle stato ossidativo dell’eritrocita, nella terza parte dello studio abbiamo analizzato alcuni markers di ossidazione sia a livello di membrana che di citosol. I nostri risultati indicano che nessuna modifica del contenuto di GSH o di proteine glutationilate (GSSP) era presente nei pazienti rispetto ai controlli, come nessuna alterazione nella monomerizzazione e attivazione della anidrasi carbonica (CA), nuovo parametro nella valutazione di un aumentato stato di ossidazione. Tuttavia, i nostri risultati mostrano che la proteina banda 3 risulta effettivamente sottoposta ad uno stress ossidativo che ne induce l’aggregazione attraverso la formazione di ponti disolfuro. Risultato, questo, che merita ulteriori indagini ed approfondimenti. In conclusione, abbiamo trovato che negli RBCs dei pazienti con PA l’Aldo è responsabile di alterazioni di membrana che portano ad una potenziale prematura rimozione delle cellule dalla circolazione. L’azione dell’Aldo viene mediata a livello citosolico dall’MR, ma non dal Cort. Ulteriori studi sono in corso per esplorare sia la natura che il meccanismo di potenziali mediatori dell’effetto dell’Aldo-MR a livello delle membrane eritrocitarie.

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Nie, Mei. "The transcriptional regulation of the human IL-8 and MCP-1 genes in cultured primary mesangial cells." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368257.

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Günther, Katharina [Verfasser], and Frank [Gutachter] Edenhofer. "Generation of early human neuroepithelial progenitors from primary cells for biomedical applications / Katharina Günther ; Gutachter: Frank Edenhofer." Würzburg : Universität Würzburg, 2018. http://d-nb.info/1160188033/34.

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Drexler, Stefan Karl. "Investigation of SIGIRR and other TIR domain containing molecules in primary human myeloid cells and rheumatoid arthritis." Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/1415.

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Key components of the innate immune response to infections are the Toll-like receptors (TLRs), which are able to detect invading pathogens and subsequently generate inflammatory responses. Many details of the signalling pathways of TLRs have emerged from gene targeted mice or inhibition studies in transformed cell lines. However, the signalling pathways activated in primary human cells and disease tissues are less well understood. Previous studies identified differences in TLR signalling between human cells of myeloid- and non-myeloid origin. While over-expression of a dominant negative construct of the TLR adaptor molecule MyD88 inhibited TLR4 signalling in HUVECs it had no effect on TLR4 signalling in macrophages. Based on this observation, this thesis examined the function of MyD88 in primary human monocyte derived dendritic cells (DCs). Unexpectedly, over-expression of MyD88 dn resulted in the activation of DCs. Subsequent experiments, provided evidence for a DC specific inhibitory mechanism, which depends on endogenous MyD88 and is disrupted by TIR domain over-expression. To further investigate the mechanism, the function of SIGIRR in human DCs was examined. SIGIRR is a member of the TIR domain containing receptor family that has been shown to be expressed in murine and human DCs but not macrophages. However, results in this thesis show that SIGIRR is expressed by human DCs as well as macrophages. While SIGIRR has been studied in murine models, nothing is known about its function in primary human cells. Therefore, an adenoviral construct encoding wild-type SIGIRR was generated and over-expressed in DCs and macrophages, which impaired TLR2, TLR3, TLR4, TLR5, TLR7/8 and IL-1R but not TNFα signalling. In accordance with these results, siRNA knock down of SIGIRR in macrophages led to an increase of TLR3, TLR4, TLR7/8 and IL-1R but not TNFα induced cytokine production. Therefore, SIGIRR seems to be an inhibitor of TIR domain dependent signalling, affecting the MyD88 dependent as well as the TRIF dependent signalling pathway. Furthermore, immunoprecipitation studies of SIGIRR with MyD88 suggest, that SIGIRR interacts with MyD88 constitutively through TIR domain interaction, indicating that SIGIRR inhibits TLR/IL-1R signalling by sequestering MyD88. Given the potency of SIGIRR to inhibit TLR/IL-1R signalling in human DCs and macrophages, this thesis further investigated its role in rheumatoid arthritis disease models. Over-expression of SIGIRR wt in human RA synovial membrane cultures inhibited the spontaneous secretion of cytokines by those cells. In contrast, SIGIRR deficient mice were resistant to collagen induced arthritis (CIA). SIGIRR null mice immunised with CIA showed a loss in IgG2a anti-collagen antibody production as well as reduced Th1 and Th17 immune responses but increased Th2 immunity. Subsequent results indicated that SIGIRR is able to regulate CD4+ T cell development through the inhibition of ST2/IL-33 signalling. Therefore, while SIGIRR inhibits pro-inflammatory cytokine release during the progression stages of RA, it may also regulate the development of Th2 development, thereby reducing CIA incidence. These studies highlight the importance of investigating signalling pathways in physiologically relevant cells in order to fully understand the roles TLRs and specific signalling molecules play in the human immune system and human disease process.

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Van, Vollenstee Fiona A. "Isolation and characterization of human adipose derived mesenchymal stem cells and production of GFP-labeled primary cells for in vivo tracking following transplantation." Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/45939.

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Introduction It is well known that resident adipose stem/stromal cells (ASCs) are a heterogeneous population of multipotent cells characterized by (a) their ability to adhere to plastic; (b) immunophenotypic expression of certain cell surface markers, while lacking others; and (c) the capacity to differentiate into cells of mesodermal origin including osteocytes, chondrocytes and adipocytes. Adipose derived stromal cells offer great therapeutic potential in multiple medical fields, including, orthopedics, cardiology, oncology and degenerative diseases, to name a few. Combining different disciplines of medicine and engineering, organ and tissue repair can be achieved through tissue engineering and regenerative medicine. Adipose derived stromal cells (ASCs) can be utilized as biological vehicles for vector-based gene delivery systems, since they home to sites of inflammation and infection in vivo. In order to reach the long-term aim of clinical translation of cell-based therapy, preclinical safety and efficacy need to be shown in animal models. This has motivated the development of standardized isolation, characterization and differentiation operating procedures as well as an in vivo tracking system for ASCs and lentiviral vector transduction for a vector-based gene delivery system. Methodology Human ASCs were isolated from lipoaspirate, expanded in culture, immunophenotyped using flow cytometery and induced to differentiate into adipogenic, osteogenic and chondrogenic lineages. Tri-lineage differentiation was confirmed by microscopy. The ASCs were then transduced with green fluorescent protein (GFP)-expressing lentiviral vectors in vitro. The effect of the GFP lentiviral vector on ASCs was investigated by studying ASC immunophenotypic expression of surface markers as well as their capacity to differentiate into osteocytes, chondrocytes and adipocytes. Results The isolated and expanded cell population, from harvested lipoaspirate adhered to recommended ASC identity criteria. The heterogeneity of ASCs was confirmed by the presence of sub-populations. Transduction efficiency in ASC cultures of approximately 80% was observed after introducing a total of 300 μl of concentrated lentiviral vector suspension per 4.8 x 104 cells. No immunophenotypic differences were observed between GFP positive and GFP negative cultures. Flow cytometric analysis revealed a progressive increase in GFP expression following in vitro expansion of transduced ASCs. Both non-transduced and transduced cultures successfully differentiated into osteocytes, chondrocytes and adipocytes. Conclusion The isolated and expanded cell population conformed to the recommended characterization criteria. Heterogeneity was demonstrated with the identification of immunophenotypic sub-populations and semi-quantification of adipogenesis was performed. ASCs were efficiently transduced using the GFP lentiviral vectors produced in our facility. In addition, transduced ASCs maintained adherence to plastic, ASC immunophenotype and were able to differentiate successfully into cells of the three lineages of mesodermal origin. This optimized GFP-ASC transduction technique offers a feasible tracking system as well as a vector-based gene delivery system for future preclinical studies.
Dissertation (MSc)--University of Pretoria, 2015.
tm2015
Immunology
MSc
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Pagni, Sarah Ellen. "Phenotypic Analysis of Dengue Virus with Different Epidemic Capacities in Primary Human Cells and Vector Contribution to Infectivity." Thesis, Icahn School of Medicine at Mount Sinai, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3594601.

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Dengue virus (DENV) is the leading cause of arthropod transmitted disease worldwide, with an estimated 2.5 billion individuals at risk for infection each year in tropical and subtropical areas. There are four serotypes of DENV which are transmitted by the mosquito Aedes aegypti and Aedes albopictus. Although DENV infections are asymptomatic, dengue disease can present as dengue fever (DF), dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS). There are several hypotheses as to explain differences in disease severity. This thesis investigates the contribution of intrinsic viral factors to the innate immune response in primary immune cells utilizing clinical isolates of DENV-3 from Sri Lanka before and after the emergence of DHF in 1989. Using these clinical isolates we analyzed their replication and innate immune phenotype in a primary human system. Our data shows an increase in interferon (IFN) and IFN-stimulated gene induction only in dendritic cells (DCs) infected with post-DHF DENV-3, compared to the pre-DHF DENV-3. Co-culture experiments reveal that DCs infected with post-DHF DENV-3 prime T cells more efficiently towards Th1 responses than DCs infected with pre-DHF DENV-3. DCs infected with post-DHF DENV-3 also undergo apoptosis at higher levels in an IFN dependent manner compared with DCs infected with pre-DHF DENV-3. Current work investigates specific mutations in the DENV NS2B3 and NS5 genes may correspond to some of the observed differences in virulence between the viruses.

Secondly, as human-to-human transmission is very rare, this thesis examines the contribution of the vector to the immune response against DENV. We investigated the innate immune response in primary cells to DENV grown in a variety of mammalian cells (primary and cell lines) in addition to DENV grown in mosquito cells and whole mosquitos. Although we do not observe a significant difference in DENV grown in mammalian cells, dendritic cells infected with mosquito DENV express higher levels of pro-inflammatory cytokines at early time points after infection. Dendritic cells treated with mosquito homogenate also upregulated these cytokines suggesting that upregulation of proinflammatory cytokines could be caused by a mosquito factor. Future experiments will examine immune responses to individual mosquito salivary factor proteins.

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Ayres, Reuben Christopher Simon. "In vitro investigation into the role of human intrahepatic biliary epithelial cells as targets in primary biliary cirrhosis." Thesis, University of Southampton, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296245.

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Singleton, Belinda Kate. "The molecular analysis of large deletions of the HPRT gene induced by ionising radiations in primary human cells." Thesis, University of Sussex, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284081.

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McLaren, John. "Human renal proximal tubular cells, in suspension and primary culture, as in vitro models of drug-induced nephrotoxicity." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU545620.

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The kidney is the target for a wide variety of chemical agents, including heavy metals, haloalkenes, analgesics and antibiotics. The functional and metabolic characteristics of the proximal tubule (PT) predispose it as the primary site for xenobiotic damage. The aim of this study was to isolate and characterise human and rat PT cells in suspension and primary culture for use as defined models to investigate drug-induced PT cell damage in vitro . A second aim was to compare the response of human and rat systems to known nephrotoxins. Human and rat PT cells (90&'37 viable) were isolated from kidney cortex by collagenase digestion followed by isopycnic Percoll density centrifugation. This resulted in the formation of two distinct bands of cell at densities 1.040g/ml (A) and 1.060g/ml (B) for both preparations. Characterisation of human cells in terms of morphology, marker enzymes, retention of active transport systems and responsiveness to parathyroid hormone indicated that &'62 95&'37 of the cells in band B were proximal tubular. Each transport system demonstrated Michaelis-Menten kinetics; kinetic parameters suggested that a higher proportion of PT cells from the S1-S2 segment of the nephron were present in human isolates. Human isolated cells also contained levels of glutathione and cytochrome P450, in particular ethoxyresorufin-O-deethylase activity, a marker for the P4501A family, similar to the intact kidney. Both human and rat cells were successfully cultured in serum-supplemented medium (10&'37 v/v) with human cells reaching confluence by 3-4 days and rat by 5-6. Maximal attachment was seen when cells from both preparations were inoculated onto collagen coated plates with an additional layer of fibronectin. Only human cells were able to reach confluence on porous membranes and demonstated an enhanced morphology when compared to normal cultured cells. Cultured cells from both preparations retained an epithelial morphology and showed minimal secondary cell contamination as shown by light microscopy and in the case of human cultures additionally through immunohistochemical staining. Immunohistochemical staining also demonstrated that human cells in culture were depositing components of the extracellular matrix. The maintenance of PT cell function, throughout the time in culture, was shown following maintenance of active transport systems, in particular the glucose carrier system and on porous membranes the organic anion system. Only rat cells maintained the organic cation system in primary culture. In addition human cells maintained the preferential response to parathyroid hormone. Except for the transport of organic cations, the other carrier systems and responsiveness to hormones were evident at both sub-confluent and confluent stages of cell culture.

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Simons, Donald Mark Lelkes Peter I. "A dissection of T cell receptor signaling pathways in primary human T cells activated in the rotating-wall vessel bioreactor /." Philadelphia, Pa. : Drexel University, 2007. http://hdl.handle.net/1860/2522.

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41

Macnair, R. "A biocompatibility study of orthopaedic materials with primary and immortalised osteoblast-like cells derived from rat and human tissue." Thesis, University of Strathclyde, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266231.

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Loh, Lip Nam. "Eschericha coli Kl interactions with human brain microvascular endothelial cells, a primary step in the development of neonatal meningitis." Thesis, London School of Hygiene and Tropical Medicine (University of London), 2011. http://researchonline.lshtm.ac.uk/923208/.

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Escherichia coli (E. coli) Kl is one of the commonest Gram negative bacteria causing neonatal bacterial meningitis in both developed and developing countries. Haematogenous spread is a key step in E. coli Kl meningitis; however, it is not clear how bacteria cross the brain endothelium to gain entry into the central nervous system. Previous studies have focussed mainly on the identification of bacterial virulence factors, as well as the signalling pathways that are activated for the recruitment of actin cytoskeleton to the bacterial adhesion site on the apical surface of human brain microvascular endothelial cells (HBMEC) and finally lead to bacterial uptake. However, the cellular requirements and mechanisms of post-invasion events are poorly understood. This study aims to further characterize E. coli KI entry, intracellular trafficking and the associated molecular mechanisms. To achieve this, a virulent fluorescent proteinexpressing E. coli K I strain was constructed. In a previous study, caveolin-l, a lipid raft marker associated with clathrin-independent endocytosis, was found associated with invading and intracellular bacteria in HBMEC. To further study the effect of caveolin-l on the bacterial entry, different caveolin-l mutants were applied here. Overexpression of caveolin-l Y 14A mutant and caveolin-l~, which is non-phosphorylatable, did not block E. coli Kl invasion of HBMEC. Furthermore, E. coli Kl invasion of caveolin-l knockout mouse lung endothelial cells (MLEC) was not blocked, which suggested that caveolin-l was not required for E. coli K 1 invasion of endothelial cells. The role of dynamin, a large GTPase that has been implicated in the membrane fission of caveolae buds, was also investigated. Based on quantitative microscopy scoring, no evidence of any inhibitory effect on the bacterial invasion was observed in cells overexpressing green fluorescent protein- (GFP) tagged dominant negative dynamin 2 [Dyn2(aa)K44A] and dominant negative dynamin 1 (DynlK44A). The experimental evidence from this study therefore suggests that E. coli Kl might invade HBMEC via a caveolae- and dynamin-independent endocytic pathway. To further explore the endocytosis pathway that the bacteria use to invade HBMEC, immunofluorescence staining of E. coli Kl infected HBMEC revealed colocalization of the bacteria with flotillin 1, another lipid raft marker associated with clathrin-independent endocytosis. However, E. coli K1 infection of flotillin 1 knockout MLEC demonstrated a significantly increased bacterial uptake. This observation suggests that E. coli K 1 uptake does not require flotillin 1. In parallel, the number of intracellular non-pathogenic E. coli K-12 recovered from the lysates of flotillin 1 knockout MLEC was also significantly higher than that recovered from the lysates of wild type MLEC. Further, overexpression of GFP-tagged flotillin 1 and flotillin 2 in HBMEC inhibited E. coli Kl invasion, which suggest flotillin might have a role as a regulatory cell barrier in host defence.

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Loro, Emanuele Loro. "Normal myogenesis and increased apoptosis in myotonic dystrophy type-1 muscle cells." Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3423200.

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Myotonic dystrophy type 1 (DM1) is caused by (CTG)n expansion in the 3’-untranslated region of DMPK gene. Mutant transcripts are retained in nuclear RNA foci, which sequester RNA binding proteins thereby misregulating their functions (i.e. splicing regulation). Controversy still surrounds the pathogenesis of the DM1 muscle distress, characterized by myotonia, weakness and wasting with distal muscle atrophy. Eight primary human cell lines from adult-onset (DM1) and congenital (cDM1) patients, (CTG)n range 90-1800, were successfully differentiated into aneural-immature and contracting-innervated-mature myotubes. Morphological, immunohistochemical, RT-PCR and Western blotting analyses of several markers of myogenesis indicated that in vitro differentiation-maturation of DM1 myotubes was comparable to age-matched controls. In all pathological muscle cells, (CTG)n expansions were confirmed by long PCR and RNA fluorescence in-situ hybridization. Moreover, the DM1 myotubes displayed the splicing alteration of insulin receptor and MBNL1 genes associated to the DM1 phenotype. Considerable myotube loss and atrophy of 15-day-differentiated DM1 myotubes indicated activated catabolic pathways, as confirmed by the presence of apoptotic (caspase-3 activation, cytochrome c release, chromatin fragmentation) and autophagic (P62/LC3) markers. Treatment with the pancaspase inhibitor Z-VAD significantly reduced the decrease in myonuclei number and in average width in15-day-differentiated DM1 myotubes. We thus propose that the muscle wasting typical in DM1 is due to impairment of muscle mass maintenance-regeneration, through premature apoptotic-autophagic activation, rather than altered myogenesis.
La distrofia miotonica di tipo 1 (DM1) è causata dall'espansione (CTG)n nella regione trascritta ma non tradotta al 3' del gene DMPK. I trascritti mutati sono trattenuti in foci nucleari, i quali sequestrano diverse proteine leganti RNA spesso alterandone le funzioni (i.e. regolazione dello splicing). A livello del muscolo, i meccanismi patogenetici che portano a miotonia, debolezza e perdita di massa dei muscoli distali, non sono ad oggi chiari. Otto linee di mioblasti primari umani, ottenuti da biopsie di pazienti affetti da DM1 nelle forme adulta e congenita (range di espansione tra 90 e 1800 CTG), sono state differenziate ed innervate con successo, ottenendo miotubi in grado i contrarre. L'analisi morfologica e la quantificazione di diversi marker di miogenesi mediante RT-PCR e Western blotting, hanno indicato che il diferenziamento in vitro dei mioblasti primari DM1 è indistinguibile da quello ottenuto con mioblasti di controllo. In ciascuna linea DM1 è stata confermata l'espansione (CTG)n mediante long-PCR ed ibridizzazione in situ. Inoltre, nei miotubi DM1 è stato rilevata l'alterazione dello splicing del recettore per l'insulina e di MBNL1, caratteristica del fenotipo DM1. A 15 giorni di differenziamento, una considerevole perdita di miotubi DM1 ha suggerito l'attivazione di pathways catabolici, come confermato dalla presenza di marker di apoptosi (taglio proteolitico della caspasi 3, rilascio di citocromo c dai mitocondri, frammentazione della cromatina) e di autofagia (aumento dei livelli di LC3 lipidato e di P62). Il trattamento con l'inibitore delle caspasi Z-VAD si è dimostrato efficace nell'attenuare la riduzione del numero di mionuclei e del calibro medio dei miotubi a 15 giorni di differenziamento. Proponiamo quindi che la compromissione muscolare tipica della DM1 sia dovuta, più che ad un'alterata miogenesi, a problemi nei meccanismi di mantenimento/rigenerazione, che si esplicano attraverso la prematura attivazione di apoptosi e/o autofagia

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Rimland, Casey. "Understanding regional diversity in the human biliary tree through transcriptomic profiling of primary tissues and in vitro derived organoids." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/286011.

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The biliary tree is a series of ductular tissues responsible for the drainage of bile produced by the liver and pancreatic secretions from the pancreas. The biliary tree is affected by a diversity of life- threatening diseases collectively called cholangiopathies. Cholangiopathies show regionalization, with some diseases such as biliary atresia predominantly targeting extrahepatic bile ducts (EHBDs) outside of the liver. Despite this, little is known on whether anatomical location within the biliary tree contributes to differences in functionality of biliary epithelium, especially in the EHBD compartment. Additionally, reports have demonstrated the possibility for in vitro culture of bile duct stem/progenitor cell organoids from both intrahepatic (IHBD) and EHBD sources. The relation of these organoid systems to each other, and to their tissue of origin, is largely unknown. In this dissertation, I address these major questions by combining transcriptional analyses and in vitro culture of human bile duct organoids derived from primary IHBD and EHBD epithelium. First, I show that in vitro organoids can be derived from four regions of the human biliary tree: gallbladder, common bile duct, pancreatic duct, and intrahepatic bile ducts. Characterization of these organoids demonstrated expression of adult stem cell (LGR5/PROM1) and ductal (KRT19/KRT7) markers suggesting these cultures contained cells with a biliary stem/progenitor phenotype. Further, I show that IHBD organoids are distinct from EHBD organoids requiring different conditions for sustained growth. Using RNA-Sequencing, I demonstrate that primary tissues from different regions of the extrahepatic biliary tree display unique expression profiles and identify novel tissue-specific markers. I also show that only a limited number of these tissue specific differences are maintained in the in vitro organoids and that the organoids are very different from their tissue of origin. Finally, I demonstrate that IHBD, but not EHBD organoids, express a low-level of hepatocyte-specific markers under differentiation conditions. Taken together, the work in this dissertation has uncovered regional specific markers for different anatomical regions of the human biliary tree. Further, I demonstrate that major differences exist between IHBD organoids and EHBD organoids in vitro and discover that only IHBD organoids have the capacity to express hepatocyte markers under differentiation conditions. Ultimately, these results may help to identify new targets for therapeutic development for cholangiopathies and regenerative medicine. They have also provided important insight to the understanding of both basic biliary physiology and also the field of biliary stem/progenitor cell organoids.

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Zielecki, Julia [Verfasser], Thomas F. [Akademischer Betreuer] Meyer, Richard [Akademischer Betreuer] Lucius, and Stefan [Akademischer Betreuer] Bereswill. "Establishment of in vitro-infection models for Chlamydia trachomatis based on human primary cells and primary tissue / Julia Zielecki. Gutachter: Thomas F. Meyer ; Richard Lucius ; Stefan Bereswill." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://nbn-resolving.de/urn:nbn:de:kobv:11-100196653.

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46

Zielecki, Julia Verfasser], Thomas F. [Akademischer Betreuer] [Meyer, Richard [Akademischer Betreuer] Lucius, and Stefan [Akademischer Betreuer] Bereswill. "Establishment of in vitro-infection models for Chlamydia trachomatis based on human primary cells and primary tissue / Julia Zielecki. Gutachter: Thomas F. Meyer ; Richard Lucius ; Stefan Bereswill." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://d-nb.info/1017495181/34.

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47

Zhang, Yuan. "Cell-cell interactions and Gossypol's effects on cell functions of primary cultured Human Breast Epthelial, Stromal and Adipose Stromal cells /." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488187763845791.

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48

Linnemann, Jelena [Verfasser], and Magdalena [Akademischer Betreuer] Götz. "An organotypic assay for the quantification and characterization of regenerative primary human mammary epithelial cells / Jelena Linnemann ; Betreuer: Magdalena Götz." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2017. http://d-nb.info/1154683699/34.

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Gonsalves, Kyle Joseph. "An exploration of RNA and miRNA expression and their role in cell cycle regulation of human primary trabecular meshwork cells." Thesis, University of Iowa, 2019. https://ir.uiowa.edu/etd/6744.

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In the Kuehn lab, it has been shown that inducible pluripotent stems cells that have been induced to be trabecular meshwork cell-like (iPSC-TM) have a unique ability to regenerate dysfunctional trabecular meshwork (TM) cells by sharing specific unknown factors. In this thesis will discuss the novel means by which I isolate primary human Trabecular Meshwork (pTMs) and efficiently prepare cell cultures for experimentation, such as a sequencing experiment in which I studied expression changes that arose when the TM cell culture’s cell cycle control is manipulated. Previous research has shown that pTM grow atypical when 100% confluent compared to other epithelial cells creating an interesting time frame by which to observe their unique cell cycle control. Using newly isolated TM cell cultures I investigated expression of mRNA and miRNA to understand their roles in cell cycle control of these atypical cultures. With regards to the isolation of TM cell cultures were able to show that the “Crawling Out” methodology is an effective way to establish a pure TM cell line with both a low contamination rate and less passages/time. With these cultures we were able to establish 50 mRNAs and 19 miRNAs that were differential expressed in the TM cell cultures that were atypically grown. When reviewing the literature many of these expression changes were linked to carcinogenics, and the progression/prognosis of various cancer types.

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Huang, Yijiang [Verfasser], and Peter [Akademischer Betreuer] Müller. "Chondrogenic differentiation and proliferation potential of human adipose-derived stem cells combined porous chitosan-based scaffolds for articular cartilage formation in vitro / Yijiang Huang ; Betreuer: Peter Müller." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1182228720/34.

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Dissertations / Theses on the topic 'Primary human articular cells'

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