Rozprawy doktorskie na temat „Statut immunitaire”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 23 najlepszych rozpraw doktorskich naukowych na temat „Statut immunitaire”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj rozprawy doktorskie z różnych dziedzin i twórz odpowiednie bibliografie.
Afriat, Mélanie Boog Georges. "Statut immunitaire et pré-éclampsie". [S.l.] : [s.n.], 2008. http://castore.univ-nantes.fr/castore/GetOAIRef?idDoc=51226.
Pełny tekst źródłaBoleslawski, Emmanuel. "Evaluation non invasive du statut immunitaire après transplantation hépatique". Paris 6, 2011. http://www.theses.fr/2011PA066618.
Pełny tekst źródłaJOSIEN, GILLE NATHALIE. "Valeur de l'elisa dans l'appreciation du statut immunitaire vis-a-vis de la rubeole". Lille 2, 1992. http://www.theses.fr/1992LIL2M142.
Pełny tekst źródłaGilles, Aurélie Meynadier Annabelle. "Effet d'une supplémentation en iode et sélénium chez la vache gestante sur le statut immunitaire du veau nouveau-né". [S.l.] : [s.n.], 2007. http://oatao.univ-toulouse.fr/1742/1/debouch_1742.pdf.
Pełny tekst źródłaLemay, Michel, i Michel Lemay. "Impact d'une ration contaminée par des mycotoxines de Fusarium sur la réponse immunitaire systémique et mucosale et la possible capacité de compléments antioxydants à rétablir le statut immunitaire de porcelets sevrés". Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27602.
Pełny tekst źródłaCe mémoire cherche à évaluer les effets du déoxynivalénol (DON) sur le système immunitaire systémique et mucosale de porcelets sevrés et d’évaluer la capacité de trois types d’antioxydants à rétablir le statut immunitaire de ces porcelets. Des porcelets ont été nourris avec l’une de six rations expérimentales : un témoin (< 0.8 mg/kg de DON); une ration contaminée au DON (3 mg/kg); un traitement contaminé par DON contenant des compléments de vitamines A, C et E; un traitement contaminé par DON contenant un complément de sélénium organique et de levures enrichies en glutathion (GSH); un traitement contaminé par DON contenant un complément de quercétine (provenant d’extrait d’oignons) et un traitement contaminé par DON contenant une combinaison des trois compléments précédents. Des prises de sang ont été effectuées afin de déterminer la concentration de cytokines, d’haptoglobine, la réponse anticorps à l’ovalbumine, les différentes populations de leucocytes et l’activité phagocytaire. Les porcelets ont été euthanasiés après 16 jours de traitements afin de récolter des échantillons de jéjunum et d’iléon. Ces échantillons ont été utilisés afin de mesurer l’expression de certains gènes ayant un rôle immunitaire. La contamination par DON a diminué le pourcentage de cellules de lignées monocytes/macrophages comparé au témoin (P< 0.05), a affecté les populations de lymphocytes T helper et de cellules NK ainsi que la concentration d’haptoglobine suggérant un effet immunosuppresseur. Pour les antioxydants, le traitement DON + vitamines a seulement permis de restaurer la concentration d’haptoglobine, le traitement de DON + sélénium-GSH a induit une réponse pro-inflammatoire, en augmentant la concentration d’interleukine 1 (IL-1) et d’interféron-γ (INF-γ) dans le sang tandis que le traitement DON + quercétine a réduit la réaction inflammatoire causée par DON et à partiellement restauré le statut immunitaire des porcelets. Dans l'ensemble, la contamination au DON et les compléments alimentaires en antioxydants ont modulé les fonctions immunitaires de porcelets sevrés alimentés avec des rations contaminées par DON.
This paper aimed to evaluate the effects of deoxynivalenol (DON) on systemic and mucosal immune systems of weanling pigs, and to evaluate the capacity of three antioxidant supplements to restore the immune status of these piglets. Piglets were fed with one of six dietary treatments: a control diet (< 0.8 mg/kg of DON), a DON contaminated diet (3 mg/kg); a DON contaminated diet supplemented with vitamins A, C, and E; a DON contaminated diet supplemented with organic selenium and a glutathione (GSH) enriched yeast; a DON contaminated diet supplemented with quercetin (from onion extract) and a DON contaminated diet supplemented with a combination of all three previous supplements. Blood samples were taken from the jugular vein to determine cytokines, haptoglobin, antibody response to ovalbumin, different leukocyte populations and phagocytosis activity. Piglets were euthanized after 16 days of treatment for jejunum and ileum sampling. These intestinal samples were used to measure the expression of genes involved in regulation of immune response. The DON contamination lowered the monocyte/macrophage lineage cell population percentage compared to control (P< 0.05), it also affected the lymphocyte T helper population, the NK cell population and the haptoglobin concentration suggesting an immunosuppressive effect. For the dietary antioxidant supplement, the DON + vitamin treatment only had an effect on restoring haptoglobin concentration; the DON + selenium-GSH treatment induced a pro-inflammatory reaction by increasing IL-1 and IFN-γ concentration in the peripheral blood and T memory lymphocyte populations while the DON + quercetin treatment reduced the inflammation effect of DON and partially restored the immune status of the piglets fed DON contaminated diet. Globally, DON contamination and dietary antioxidant supplementation did modulate immune function of pigs fed DON contaminated diet. However, further studies are required to determine their potential to mitigate the effect of DON on innate and acquired immunity.
This paper aimed to evaluate the effects of deoxynivalenol (DON) on systemic and mucosal immune systems of weanling pigs, and to evaluate the capacity of three antioxidant supplements to restore the immune status of these piglets. Piglets were fed with one of six dietary treatments: a control diet (< 0.8 mg/kg of DON), a DON contaminated diet (3 mg/kg); a DON contaminated diet supplemented with vitamins A, C, and E; a DON contaminated diet supplemented with organic selenium and a glutathione (GSH) enriched yeast; a DON contaminated diet supplemented with quercetin (from onion extract) and a DON contaminated diet supplemented with a combination of all three previous supplements. Blood samples were taken from the jugular vein to determine cytokines, haptoglobin, antibody response to ovalbumin, different leukocyte populations and phagocytosis activity. Piglets were euthanized after 16 days of treatment for jejunum and ileum sampling. These intestinal samples were used to measure the expression of genes involved in regulation of immune response. The DON contamination lowered the monocyte/macrophage lineage cell population percentage compared to control (P< 0.05), it also affected the lymphocyte T helper population, the NK cell population and the haptoglobin concentration suggesting an immunosuppressive effect. For the dietary antioxidant supplement, the DON + vitamin treatment only had an effect on restoring haptoglobin concentration; the DON + selenium-GSH treatment induced a pro-inflammatory reaction by increasing IL-1 and IFN-γ concentration in the peripheral blood and T memory lymphocyte populations while the DON + quercetin treatment reduced the inflammation effect of DON and partially restored the immune status of the piglets fed DON contaminated diet. Globally, DON contamination and dietary antioxidant supplementation did modulate immune function of pigs fed DON contaminated diet. However, further studies are required to determine their potential to mitigate the effect of DON on innate and acquired immunity.
Fortin, Guérin Samanta. "Évaluation des différences en immunité et en survie entre les oisillons de statut paternel différents chez l'hirondelle bicolore". Mémoire, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5404.
Pełny tekst źródłaMONGET, ANNE-LAURE. "Statut en micronutriments antioxydants et effets d'une supplementation chez le sujet age institutionnalise ; consequences sur le metabolisme oxydatif et l'etat immunitaire". Paris 7, 1995. http://www.theses.fr/1995PA077141.
Pełny tekst źródłaAmiell, Serge. "Tétanos, poliomyélite et diphtérie : étude du statut vaccinal de l'adulte et de la réponse immunitaire en fonction de l'âge à 3 types de vaccins". Bordeaux 2, 1990. http://www.theses.fr/1990BOR25099.
Pełny tekst źródłaNeveu, Bérangère. "Analyse de réponses lymphocytaires T CD8+ dirigées contre le virus de l'hépatite C : corrélation avec le statut clinique". Nantes, 2007. http://www.theses.fr/2007NANT2093.
Pełny tekst źródłaUp to 170 million people are infected by hepatitis C virus (HCV), among whom 4/5 remain chronically infected and are predisposed to cirrhosis and/or hepatocarcinoma. To better understand the mechanisms that influence progression to HCV chronic infection versus viral control, we performed an in-depth functional and molecular analysis of highly purified HCV-specific T cells in seropositive donors, having resolved their infection or not, and in HCV-seronegative healthy donors. We managed to isolate from blood samples HCV-specific CD8+ T cells directed against three immunodominant HCV epitopes restricted by HLA-A*0201, using magnetic beads coated with HLA class I/peptide complexes. T cell populations specific to those antigens were isolated from almost all donors, irrespective of their serological status. Chronically infected patients yielded weaker HCV-specific CD8+ responses than those having cleared their infection, as assessed by IFN- production, cytotoxicity and degranulation assays. These functional differences were primarily accounted for by decreased frequency of specific T cells expressing high-affinity TCR in chronically infected patients rather than by intrinsic T cell functional defects or by active downmodulation by inhibitory receptors. Healthy donors yielded mainly low avidity HCV-specific T cell responses, very similar to chronic patients, although high avidity subsets were detected in some individuals. Our results indicate that enrichment for high avidity T cells is associated with successful viral clearance and suggest a link between the quality of the initial HCV-specific T cell repertoire and susceptibility to chronic infection
Müller, Judith Elisabeth. "Neisseria meningitidis: portage et statut immunitaire au décours d´une épidémie liée au sérogroupe W135 dans la Ceinture africaine de la méningite et leur interprétation pour une stratégie préventive". Paris 6, 2008. http://www.theses.fr/2008PA066198.
Pełny tekst źródłaNicola, Celeste. "Thérapies du cancer de nouvelle génération et fonctions cognitives : Nouveaux concepts, nouveaux mécanismes, biomarqueurs originaux". Electronic Thesis or Diss., Normandie, 2023. http://www.theses.fr/2023NORMR050.
Pełny tekst źródłaAdvances in oncology have considerably improved the overall survival of cancer patients, thus understanding their toxicities and cerebral impacts is a major issue to maintain patients' quality of life (QoL). Certain cancer treatments can indeed lead to cognitive dysfunctions referred to as "cancer related cognitive impairment" (CRCI), which can impair Qol and compromise the autonomy of elderly patients. In this thesis work, we leverage preclinical models to decipher the direct impact of new-generation hormone therapies used in prostate cancer and of immunotherapies in the immune and inflammatory context linked to cancers, in the occurrence of cognitive, and/or emotional deficits as well as "fatigue". In a first study, we demonstrated the impact of the hormone therapies Enzalutamide and Abiraterone Acetate/Prednisone on exploration activity and spatial learning, in relation to brain altered dopaminergic transmission. In a second work, we showed that systemic inflammation, blood-brain barriers permeability accompanying meningeal infiltration of peripheral macrophages and neuroinflammation as well as deficits in cognition or emotional reactivity, depending on immuno-inflammatory or immune-desert cancer type. Combined with cancers, anti-PD-1 or -PD-L1 treatments exacerbate the decline in executive functions, while PD-L1 specifically relays the infiltration of a lymphocyte subpopulation in meninges implicated in cognitive deficits and anxiety. This work proposes new systemic biomarkers and original ways of intervention to improve the cancer patients QoL treated with new-generation therapies
Morell, Ginestà Mireia. "Disseny d'una pauta immunosupressora en un model de xenotrasplantament hepàtic en rosegadors: alteracions del sistema immunitari i del status hemostàtic". Doctoral thesis, Universitat de Barcelona, 2004. http://hdl.handle.net/10803/861.
Pełny tekst źródłaLes principals conclusions a que s'han arribat són que en el model de xenotrasplantament hepàtic ortotòpic hàmster-rata, es poden aconseguir supervivències indefinides en monoteràpia amb Tacrolimus a dosis baixes sense que es manifesti cap signe de rebuig i amb una correcta funció de l'empelt. S'ha vist que l'increment de la subpoblació de limfòcits T CD4+CD45RC- i la presència de gran quantitat de cèl·lules B (i no cèl·lules plasmàtiques) en els empelts de les rates xenotrasplantades, juntament amb el bon estat general dels animals, una preservació total de la histologia, una bona funció hepàtica, un equilibri de l'status hemostàtic acompanyat d'uns nivells molt baixos d'immunosupressió, ens fa assegurar que en aquests animals s'està donant un procés d'acceptació indefinida de l'empelt que anomenem "protolerant". Que els canvis de les proporcions i del nombre total de cada subpoblació limfocitària en sang perifèrica són bons indicadors del que està succeint a l'empelt i no s'observen diferències entre al·lotrasplantament i xenotrasplantament. En el model utilitzat de xenotrasplantament hepàtic es produeix una activació de la trombosi en els primers dies postrasplantament deguda a un desequilibri general com a conseqüència del recanvi de tots els components de síntesi hepàtica, però que no comporta més problemes perquè és corregida amb el temps i l'animal receptor adopta el perfil de paràmetres hemostàtics de l'espècie donant. L'administració continuada de l'antagonista del PAF UR-12670 a una dosi de 20 mg/kg no és suficient per perllongar la supervivència de l'empelt i induir tolerància. Tanmateix modula la resposta cel·lular, redueix la infiltració leucocitària, condiciona les subpoblacions limfocitàries infiltrants al parènquima, té un efecte citoprotector sobre els hepatòcits i millora l'estat general de l'empelt suggerint la implicació del PAF en el rebuig tardà del xenoempelt (LXR). I finalment podem dir que en el model de xenotrasplantament hepàtic hàmster-rata no es dóna un canvi d'especificitat dels anticossos d'isotip IgM a diferents dies postrasplantament. Així mateix, aquests anticossos polireactius de l'isotip IgM presents al sèrum de les rates xenotrasplantades a diferents dies postrasplantament no són específics d'espècie.
Grissa, Oussama. "Défenses antioxydantes, inflammation et immunomodulation, au cours du diabète gestationnel, dans les compartiments maternel, foetal et placentaire". Thesis, Dijon, 2010. http://www.theses.fr/2010DIJOS099/document.
Pełny tekst źródłaGestational diabetes mellitus (GDM) is defined as ‘carbohydrate intolerance of variable severity with onset or first recognition during pregnancy’, irrespective to necessary treatment and its evolution in the post partum. GDM is associated with a number of complications/ pathologies both in mother and in their newborns, with short and long-term. In this study, we investigated the role of cytokines, adipokines and antioxidant status during GDM and macrosomia. Our study has demonstrated that these pathologies are associated with a perturbation in lipid metabolism, and antioxidant and immune status. GDM is linked to the down-regulation of adiponectin along with Th1 cytokines and upregulation of leptin and inflammatory cytokines whereas macrosomia was associated with the up-regulation of Th1 cytokines and the down-regulation of the obesity-related agents (IL-6, TNF-α, leptin and adiponectin). Several alterations observed at birth in carbohydrates and lipids metabolism in the children born to diabetic mothers, still persist at the adulthood. It seems that in utero programming during diabetic pregnancy creates a ‘‘metabolic memory’’ which is responsible for the development of obesity and physiological anomalies in macrosomic offspring. According to multiple linear regressions incremental that we established, it appears that growth factors that influence the increase of foetal weight are: PDGF in mother's side and FGF2 in maternal and foetal side
Barlogis, Vincent. "Déterminants de l'état de santé et de la qualité de vie des patients atteints de déficits immunitaires primitifs diagnostiqués au cours de leur enfance". Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0201.
Pełny tekst źródłaImportance: Most children with primary immunodeficiencies (PID) now reach adulthood. Assessment of their long-term health status represents a major challenge. We aimed to gain insight into how PID affects patient health status and quality of life (QoL). Design: The French Reference Center for PIDs (CEREDIH) initiated a prospective multicenter cohort which enrolled participants who met all inclusion criteria: (1) patient with PID included in the CEREDIH registry, (2) clinical diagnosis before 18 years, (3) alive and living in France. Among 1810 patients eligible for inclusion (on 1/17/2016), 1047 were children, and 763 were adults. A severity score was assigned to each health condition: grade 1 (mild) to grade 4 (life-threatening/disabling). We report the health status of children by focusing on two endpoints: grade 4 conditions and grade 3 or 4 conditions. Results: In the adult study, only 12% of adults with PID had never experienced severe or life-threatening conditions, and 7.6% of patients had been diagnosed with cancer. Furthermore, adults reported significantly lower scores for all domains of QoL, and QoL was strongly associated with poor health conditions. In the pediatric study, the response rate was 62.5%. Of the 656 children participants, 83% experienced at least one grade 3 or 4 condition. Children with PID scored significantly lower for most QoL domains. QoL was strongly associated with heavy burden of health conditions. Conclusions: Taken together, these studies demonstrate that the deleterious health effects bore by patients with PID become heavy since childhood, emphasizing the need to establish multidisciplinary healthcare teams, from childhood
Maalem, Aïda Selma. "Rôle du facteur de transcription STAT5b dans la fonction tolérogène des cellules dendridiques chez la souris NOD". Mémoire, Université de Sherbrooke, 2013. http://hdl.handle.net/11143/6340.
Pełny tekst źródłaAlbert, Vega Chloé. "Definition of an Immune Functional Assay in order to characterize the altered immune status of septic patients". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEN006.
Pełny tekst źródłaOne person dies of sepsis every 3.5 seconds leading the WHO to adopt sepsis as a global health priority in 2017. The new definition of sepsis changed in early 2016 and is now defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. The complex pathophysiology of sepsis, yet not well-understood, together with the inter-individual variability makes of sepsis a very heterogeneous condition. In addition, sepsis is a very variable condition which evolves over time. Until now, all the anti-inflammatory and immunostimulant therapies tested have not been proven beneficial when applied to an unselected sepsis population. Stratification has then been proposed as the best approach to achieve immunorestoration among sepsis patients. Accordingly, ex vivo stimulation, called immune functional assays (IFA), offers the possibility to monitor the dynamics of the disease while evaluating the function of the immune cells, the potential restoration of the immunity and anticipating the response of the cells to immunotherapy. In this project, we developed a standardized IFA tested on healthy donors using lipopolysaccharide (LPS) and staphylococcal enterotoxin B (SEB) stimuli as triggers of the innate and adaptive immunity, respectively, and evaluated the response measuring gene expression with the NanoString technology. First, we assessed an independent validation of the assay through a 44-gene signature transcription to test the reproducibility and robustness of the IFA, as referred to a published study. Then, using two independent cohorts of septic patients, our standardized IFAs confirmed a profound innate immune alterations shared by all septic patients. Heterogeneity in the alterations of the adaptive immune arm was captured after ex vivo stimulation using an enhanced transcriptomic read-out consisting of 86 genes, which made possible to identify groups of patients with an immune restoration potential. Finally, we opened few lines of investigation seeking to optimize the IFA with clinical implementation aims. Screening of synthetic compounds for the stimulation and reduction in time-to-results were evaluated. This brings us a step closer to the development of an immune monitoring tool in sepsis to implement at the bedside
Le, Bourgot Cindy. "La supplémentation périnatale en fibres prébiotiques (fructo-oligosaccharides à courte chaîne, scFOS) modifie le microbiote intestinal et programme le phénotype métabolique et immunitaire du porc, pris comme modèle de l’Homme". Thesis, Rennes, Agrocampus Ouest, 2016. http://www.theses.fr/2016NSARB285/document.
Pełny tekst źródłaPerinatal scFOS supplementation modifies metabolic response to an unbalanced diet in adults by stimulating intestinal endocrine function and pancreas sensitivity to glucose, by reducing risks of inflammation, and in fine by changing metabolic homeostasis in association with modifications of microbiota.In summary, prebiotic consumption during perinatal life programs the immune and metabolic phenotype of adults through persistent modulations of intestinal microbiota. The integrated approach of data enables us to identify molecular actors involved in the differential adaptation of individuals to an unbalanced diet according to their perinatal nutrition
Cohen, Romain. "Caractérisation phénotypique et clinique des cancers colorectaux métastatiques avec instabilité des microsatellites Clinical and molecular characterization of hereditary and sporadic metastatic colorectal cancer harbouring microsatellite instability/DNA mismatch repair deficiency Association of primary resistance to immune checkpoint inhibitors in metastatic colorectal cancer with misdiagnosis of microsatellite instability or mismatch repair deficiency status". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS313.
Pełny tekst źródłaMicrosatellite instability (MSI) is a tumor phenotype linked to somatic or germline inactivating alterations of DNA mismatch repair (MMR) genes. MSI is observed in approximately 5% of metastatic colorectal cancers (mCRC) and has recently emerged as a major positive predictive biomarker for the efficacy of immune checkpoint inhibitors (ICKi) amongst mCRC patients. The objectives of my work was to clinically and molecularly characterize MSI mCRC, to evaluate the accuracy of MSI screening methods and the response to immunotherapy in the context of ICKi clinical trials. Fist, I show that sporadic and inherited MSI mCRC display distinct natural history (Cohen et al., Eur J Cancer 2017). In a second work, I show that MSI testing in routine practice is associated with almost 10% of false positives due to misinterpration of IHC and PCR assays. Moreover, these false-positives are the main cause of mCRC primary resistance to ICKi observed in clinical trials (Cohen*, Hain* et al., JAMA Oncol. 2018). After summarizing the literature concerning MSI, its consequences on CRC and immunotherapy, I present the results of the nosologic and diagnostic works developed during this doctoral thesis. Then I will go on perspectives in the context of MSI cancer
Delfortrie, Suzanne. "Rôle de la VE-statine (EGFL7) dans la tumorigenèse : répression de l'activation des cellules endothéliales et contribution à l'échappement à l'immunité anti-tumorale". Phd thesis, Université du Droit et de la Santé - Lille II, 2011. http://tel.archives-ouvertes.fr/tel-00693157.
Pełny tekst źródłaNaulleau, Catherine. "Supplémentation en glutamine et statut immunitaire de nageurs élites en compétition". Thèse, 2008. http://hdl.handle.net/1866/2703.
Pełny tekst źródłaThe purposes of this study were to determine the positive impacts of glutamine supplementation upon immune system status and to determine whether changes in plasma glutamine relate to the appearance of upper respiratory tract infections (URTI) in elite swimmers. Furthermore, this study evaluated dietary intakes and its influence on immune parameters and URTI incidence. Fourteen athletes (8 men, 6 women) took part of the study. Each athlete participated in both experimental conditions: glutamine supplement and an isocaloric solution placebo. The supplementation period lasted seven day, including three consecutive competing days. Post competing hematologic profils of swimmers show that glutamine supplement does not significantly improve plasma glutamine neither cytokines levels, compared to a placebo solution. Even if plasma glutamine concentrations are similar with both conditions, the post competiting levels tend to be higher than pre competing values, when glutamine is supplemented. Futhermore, plasma glutamine levels show a decreasing trend under control conditions (p=0.060). In this study, URTI can not be explained by low plasma glutamine or supplemented glutamine. However, URTI incidence is higher after competitions, where 8 athletes showed symptoms (control group) and 3 only in the experimental group. Athletes with URTI seem to consume less energy and proteins than healthy athletes (p=0.060). These data does not suggest that glutamine supplementation improves immune function or prevents URTI in highly trained swimmers during competition. However, results support the hypothesis that exogenous glutamine stabilizes plasma glutamine levels, allowing athletes to tolerate training workload and recover properly.
Jinane, Noureddine. "Effet de la source du sélénium sur le statut du sélénium, de la GSH-Px et sur le système immunitaire des bovins de boucherie". Thèse, 2010. http://hdl.handle.net/1866/5160.
Pełny tekst źródłaAbstract The aims of this study were to determine the effects of selenium (Se) supplementation sources (organic and inorganic) on Se and GSH-Px concentrations of beef cows (n=33) and their calves and on immune parameters of the calves. Two groups of cows were given daily 3 mg of either organic or inorganic Se in mineral supplement starting from 12 weeks before calving until weaning. The third group had no Se added into the diet and their calves were divided into two subgroups either injected or not with 0.087 mg/kg of sodium selenite after birth. Serum Se and whole blood GSH-Px were respectively measured by HPLC-UV and by kinetic-enzymatic technique. Calves immune parameters were evaluated using commercial kits for phagocytosis, respiratory burst and CD4:CD8 ratio and radial immunodiffusion for total IgG concentrations. In cows and calves, Se supplementation increased significantly serum and colostrum Se concentrations (P<.02) with significant higher effect for organic source. However, milk Se concentrations increased significantly only with the organic source (P≤.0007). Se supplementation increased GSH-Px concentrations in cows (P≤.04) and their calves (P≤.0004); organic source induced a higher effect than inorganic one in calves (P≤.0004). Se injection in calves allowed a temporary increase (P<.0001) of serum Se concentrations. No significant differences were noticed throughout the experiment for all of the immune parameters measured (P>.01, not significant after Bonferroni adjustment). Our results showed that Se supplementation improved colostrum, milk and serum Se and GSH-Px concentrations in cows and their calves without effect on the measured immune parameters in calves. Key words: selenium, beef calves, phagocytosis, respiratory burst, antibodies, CD4:CD8 ratio, GSH-Px.
Sicotte, Maryline. "Malnutrition, VIH et traitement antirétroviral dans les pays à ressources limitées". Thèse, 2014. http://hdl.handle.net/1866/12310.
Pełny tekst źródłaZerif, Echarki. "Mécanismes cellulaires et moléculaires des fonctions tolérogèniques et immunogéniques des cellules dendritiques dans les réponses auto-immunes". Thèse, 2017. http://hdl.handle.net/1866/19331.
Pełny tekst źródłaThe contribution of DCs in the initiation and progression of autoimmune diseases is well established. Several studies have reported that phenotypic and functional abnormalities of DCs, in Non Obese Diabetic (NOD), contribute to spontaneous type 1 diabetes (T1D) development. DCs are among the first cells that infiltrate the pancreatic islets, produce excessive amounts of pro-inflammatory cytokines, and contribute to the activation of T effector cells (Teff). This increased ability of DCs to activate Teff is regulated by several intracellular signaling pathways. STAT5 is among the critical transcription factors in the regulation of genes associated with the development, maturation and functions of DCs. The predisposition to T1D in NOD is determined by several regions of susceptibility to diabetes (idd1-20). Interestingly, the Stat5b gene is located in the idd4 susceptibility region in NOD mice suggesting its involvement in the development of diabetes. Recent studies have identified a dysfunction in the Jak-Stat5 signaling pathway in NOD mice, including the presence of a mutation (L327M) at the DNA-binding domain of Stat5b which alters its binding to DNA. Furthermore, previous studies from our laboratory have shown that the GM-CSF- or TSLP-conditioned DCs, which activate the Jak-Stat5 signaling pathway, is a potential pathway for immunotherapy in NOD mice. These data suggest a central role for Stat5b in the regulation of tolerogenic functions of the immune cells. Here, we generated a transgenic NOD mouse model (NOD.CD11cStat5b-CA) that constitutively express the active form of STAT5B from the C57BL/6 mouse specifically in DCs. Our results showed that these transgenic mice are completely protected against autoimmune diabetes. This long-term diabetes protection is associated with the acquisition of tolerogenic functions by Stat5b-CA.DCs, that exhibit a mature tolerogenic phenotype, overexpression of immunoregulatory molecules (PD-L1 and PD-L2) and produce anti-inflammatory cytokines (TGF-β) and a significantly decrease their production of pro-inflammatory cytokines (IL-12p70, TNF-α and IL-23). Moreover, we have highlighted the role of STAT5B in the upregulation of IRF4 and also the involvement of the STAT5B/ EZH2 complex in downregulation of IRF8. This differential regulation of the Irf4 and Irf8 genes expression is accompanied by promoting the development of CD11c+CD11b+ DC subset. Furthermore, we demonstrated that the tolerogenic Stat5b-CA.DCs were able to restore and maintain peripheral immune tolerance to autoantigens, which is associated with their high ability to induce conversion and expansion Tregs and to promote Th2 and Tc2 immune deviation. We also demonstrated that a single intravenous injection of Stat5-CA.DCs (splenic or bone marrow derived dendritic cells) or Tregs from transgenic mice NOD.CD11cStat5b-CA halted ongoing diabetes in recipient NOD mice. Thus, our study provides clear evidence that the correction of the Jak-Stat5b signaling pathway defect in DC of NOD mice induces long-term protection against diabetes suggesting that signaling pathway can be a potential therapeutic target not only in the context of type 1 diabetes but also in other autoimmune diseases.