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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
931

Histone acetylation and inflammatory mediators in inflammatory bowel disease

Tsaprouni, Loukia G. January 2003 (has links)
During cell activation the tightly compacted DNA is made available to DNA-binding proteins allowing the induction of gene transcription. In the resting cell, DNA is packaged into chromatin whose fundamental subunit is the nucleosome, composed of an octamer of four core histones (H) 3, 4, 2A and 2B. During the induction of gene transcription, modification of histones, by acetylation, methylation etc., results in unwinding of the DNA, permitting access of large DNAbinding proteins, such as RNA polymerase II, and subsequent induction of gene transcription. This investigation initially examined the effects of pro-inflammatory stimuli LPS and TNF-a on the production of IL-8 in a macrophage cell line (U937 cells) and in two T-cell lines (Jurkat and HUT-78 cells) as a marker of NF-KB-directed inflammatory gene expression. The ability of dexamethasone (Dex) and triamcinolone acetonide (TA) (synthetic glucocorticoid agonists) to suppress expression of the inflammatory cytokine IL-8 and to regulate histone acetylation was also investigated in these cells. LPS and TNF-a caused an increase in IL-8 expression, which was further enhanced by the histone deacetylases inhibitor trichostatin A (TSA), suggesting a role for histone acetylation in IL-8 production in these cells. Dex and TA, repressed LPS- and TNF-a -induced IL-8 expression in all three cell lines. This effect of both Dex and TA was attenuated by TSA in all cell lines studied, where the effect of TSA was greater in TA stimulated cells. Stimulation of all cell lines with LPS and TNF-a induced acetylation of H4 lysine residues (K5, 8, 12 and 16), the highest elevation of which was for K8 and K12. Also demonstrate is a K5 and K16 specificity of acetylation by glucocorticoids, apparent in all cell lines studied. Dex and, to a greater extent, TA suppressed LPS- and TNFa-induced K8 and K12 acetylation. TSA attenuated the inhibitory effect of the glucocorticoids for all three cell lines. An inCrease in HDAC activity with GCs was observed and ChiP assay showed these events occur on the native IL-8 promoter via histone acetylation. Further studies investigated whether there were any links between histone acetylation and the regulation of apoptosis. It was showed that TSA induced apoptosis in cells previously stimulated with the inducer of oxidative stress hydrogen peroxide (H20 2). Studies into the activation of caspase 3 in LPS- and TNF-a stimulated cells revealed that the combinatory effect of Dex or TA with TSA Significantly enhanced expression of the marker in all three cell lines. In resting cells, Dex, and TA, in the presence of TSA downregulated caspase 3 expression. These findings support the notion that glucocorticoid actions on apoptosis is mediated, at least in part, through an action on histone acetylation. Finally, histone acetylation was investigated in vivo in two rat models of inflammation and in human subjects with inflammatory bowel disease (IBD). The results showed an increase in histone H4 acetylation lysine specificity of acetylation on K8 and K12 in inflamed tissue and Peyer's patches in animal models and in IBD patients. Whereas H3 acetylation was not elevated to the same extent in tissue and was restricted to the mantle zone of Peyer's patches. In general, the present studies on histone acetylation and inflammation (in animal models and IBD patients) underlined the possibility of a general mechanism linking activation of the transcription factor NFKB with histone acetylation. The ultimate objective of this work is to aid in the understanding of the mechanisms of how deregulation of chromosome structure leads to progression of the disease state. This knowledge may aid in the development of new therapeutic approaches or improved glucocorticoids.
932

Novel family of CB2R agonists regulates inflammatory responses

Christou, Ivy January 2012 (has links)
Inflammation is a multifactorial response towards noxious stimuli, however appropriate regulation and resolution of inflammation is crucial for the prevention of chronic inflammatory diseases such as atherosclerosis. The endocannabinoid (eCB) system is an endogenous immunomodulatory system which consists of a series of lipophilic ligands that signal via two G-protein-coupled receptors. Cannabinoid receptor 1 (CB1R) is mainly expressed in the central nervous system and its activation has psychoactive effects. Cannabinoid receptor 2 (CB2R) is mainly expressed on leukocytes and receptor activation has anti-inflammatory actions in mouse models of atherosclerosis and chronic inflammatory pain. It is considered that CB2R activation is involved in modulation of the recruitment of inflammatory cells, especially monocytes/macrophages; however the exact mechanism of action has not been fully elucidated. We hypothesised that activation of CB2R modulates monocyte/ macrophage recruitment and signalling, thus providing a homeostatic mechanism to limit macrophage activation in inflammatory responses. The high lipophilicity of cannabinoid ligands and their lack of selectivity for CB2R over CB1R limits CB2R drug development. In collaboration with Dr Angela Russell, we used virtual screening and a CB2R cAMP assay that we validated to discover a novel CB2R agonist, 3-((2’-Cyanobenzyl)thio)-5H-[1,2,4]triazino[5,6-b]indole, (DIAS2). In collaboration with Dr Russell’s group who did chemical synthesis, we extended this novel scaffold to include over 80 compounds. Using the same hCB2R cAMP screening assay we demonstrated that 16 compounds with the same scaffold are at active at CB2R in the nanomolar range. At least 3 compounds, including DIAS2, were found to be ≥ 300-fold selective for CB2R over CB1R in cAMP assays and radioligand binding studies. In the inflammatory model of zymosan-induced peritonitis, DIAS2 dose-dependently inhibited inflammatory monocyte recruitment by 50% at highest dose of 5 mg/kg with no effect on neutrophils. In further zymosan-induced peritonitis experiments 5 mg/kg of DIAS2 and a structurally-similar CB2R agonist from the same family of triazino-indoles inhibited monocyte recruitment while a different CB2R agonist (JWH-133) at 5 mg/kg did not inhibit monocyte recruitment. Analysis of peritoneal exudates showed that the inhibition of monocyte recruitment was not associated with changes in the levels of JE, MIP-1α and nitric oxide but was associated with increased levels of the chemokine KC. Using in vitro cell biology approaches, we demonstrated that 10μΜ dose of both DIAS2 and JWH-133 reduced forskolin-induced cAMP production in primary murine macrophages. Also 2.5 to 10 μΜ οf JWH-133 and HU-308 dose-dependently induced primary murine macrophage chemotaxis which could be blocked a CB2R antagonist (SR 144528, 1 μΜ) while DIAS2 at doses up to 10 μΜ was not a chemoattractant. Accordingly HU-308 and JWH-133 were at least 3-fold more efficacious than DIAS2 at recruiting β-arrestin to the murine CB2R. Moreover in studies with primary murine macrophages 10 μΜ dose of JWH-133 and HU-308 induced ERK1/2 and Akt phosphorylation within 30 minutes, while 2-AG (an endogenous eCB ligand) and DIAS2 at 10 μΜ had no such effect. In summary, we have discovered a novel family CB2R agonists and demonstrated that some devoid of chemotactic active CB2R agonists can reduce monocyte recruitment in vivo while other chemoattractant CB2R agonists have no in vivo anti-inflammatory effect. We propose that non-chemotactic CB2R agonists represent a new class of anti-inflammatory drugs with a novel mode of action.
933

The effects of high intensity interval training on resting mean arterial pressure and C-reactive protein content in prehypertensive subjects

Skutnik, Benjamin C. January 1900 (has links)
Master of Science / Department of Kinesiology / Craig A. Harms / Subjects with prehypertension are at risk for developing hypertension (HTN). Hypertension is associated with low-grade systemic inflammation (LGSI). Aerobic exercise training (ET) is a proven means to reduce both blood pressure and LGSI in healthy and diseased subjects. Recently, high intensity interval training (HIIT) has been show to elicit similar cardiovascular and metabolic adaptations as ET in healthy and at-risk populations in a more time efficient manner. Therefore, we hypothesized that HIIT would elicit greater reductions in blood pressure and LGSI than ET. Twelve pre-hypertensive subjects (systolic blood pressure 127.0 ± 8.5 mmHg; diastolic blood pressure 86.2 ± 4.1 mmHg) were randomly assigned to an ET group (n=5) and a HIIT group (n=7). All subjects performed an incremental test to exhaustion (VO2max) on a cycle ergometer prior to, after 4 weeks, and after 8 weeks of training. Resting heart rate and blood pressure were measured prior to and three times a week during training. LGSI was measured via high-sensitivity C-reactive protein (hs-CRP) prior to, after 4 weeks and after 8 weeks of training. ET subjects performed an eight week exercise training program at 40% VO2 reserve determined from the VO2max test, while HIIT subjects performed exercise at 60% peak power determined from the VO2max test. ET group trained four days/week while HIIT trained three days/week. ET exercised for 30 minutes continuously at a constant workload and cadence of 60 rpm while HIIT performed a protocol on a 1:1 work-to-rest ratio at a constant workload and cadence of 100 rpm. Both groups showed similar (p<0.05) decreases in mean arterial (ET = -7.3%, HIIT = -4.5%), systolic (ET = -6.6%, HIIT = -8.8%), and diastolic (ET= -9.7, HIIT= -8.2%) blood pressure. HIIT decreased in LGSI (-33.7%) while ET did not change LGSI (p>0.05). VO2max increased ~25% with both HIIT and ET with no differences (p>0.05) between groups. These data suggest both HIIT and ET similarly decreased resting blood pressure and increased VO2max while HIIT was effective in decreasing LGSI in subjects who were pre-hypertensive.
934

The effect of the anti-inflammatory drug sodium salicylate in mature periparturient dairy cattle and immortalized bovine mammary epitheilal (MAC-T) cells

Montgomery, Shawnee January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Barry Bradford / During the transition period, 3 wk before to 3 wk after calving, dairy cows experience a variety of sudden hormonal and metabolic shifts that could result in metabolic disorders or diseases, which can be detrimental to the productive life and longevity of the cow. Cows undergo a negative energy balance, where they cannot consume enough feed to meet their energy requirements. To make up this deficit, cows mobilize adipose tissue in the form of non-esterified fatty acids (NEFA) which are transported to the liver and are either used for fuel or stored as triglycerides. High levels of circulating NEFA can lead to endoplasmic reticulum (ER) stress, which is linked to inflammation. This low-grade inflammation can compromise cell function. To mitigate this inflammation, sodium salicylate, a non-steroidal anti-inflammatory drug (NSAID), was given to mature (3+ parity) cows for 7 d after parturition via their drinking water. Blood was collected daily and a glucose turnover assay was performed. Liver, muscle, and adipose tissue was collected on d 7. Overall, it appeared that SS increased insulin sensitivity and depressed gluconeogenesis post-transcriptionally. Multiple in vitro studies were performed on immortalized bovine mammary epithelium (MAC-T) cells to determine the action of SS when ER stress was induced with palmitate (PALM). Treatment with SS did not mitigate, and in some cases exacerbated, the ER stress response. The addition of bovine serum albumin (BSA), a common component of cell culture media, may alter reactive oxygen species (ROS) measurements due to its antioxidant property. Overall, SS seems to alter metabolic processes and the cellular response to stress.
935

Regulation of oxidative stress and inflammation in ischemia/reperfusion-induced acute kidney injury

Wang, Pengqi 06 April 2016 (has links)
Renal ischemia/reperfusion (I/R) is a main cause of acute kidney injury (AKI) and delayed graft function after renal transplantation. Previous studies in human and experimental models have identified that inflammation and oxidative stress are two key players in renal I/R injury. However, the underlying mechanisms remain speculative. The overall objective of the study was to investigate the biochemical and molecular mechanisms of I/R-induced renal injury and the effect of tyrosol supplementation on I/R-induced kidney oxidative stress damage. In the present study, renal I/R was induced in Sprague-Dawley rats and in a human kidney proximal tubular cell line. A significantly elevated expression of pro-inflammatory cytokine expression (MCP-1, IL-6) was observed. There was a significant decrease in mRNA and protein levels of two hydrogen sulphide (H2S)-producing enzymes, CBS and CSE, with a concomitant reduction of glutathione and H2S production. In the cell culture model, hypoxia–reoxygenation of proximal tubular cells led to a decrease in CBS and CSE expression and an increase in pro-inflammatory cytokine expression. Supplementation of glutathione or H2S donor (NaHS) effectively abolished cytokine expression in tubular cells. Experiments were conducted to detect oxidative stress markers. It was demonstrated that there was a significant increase in peroxynitrite formation and lipid peroxidation in the kidney after I/R insult, which might be caused by the elevation in nitric oxide (NO) metabolites and inducible nitric oxide synthase (iNOS). Administration of tyrosol, a natural phenolic compound, reduced peroxynitrite formation, lipid peroxidation and the level of NO metabolites via inhibiting NF-B activation and iNOS expression. Tyrosol treatment improved kidney function and had a protective effect against I/R-induced AKI. The present study has clearly demonstrated that (1) there is a reduction of H2S production via inhibition of CBS and CSE expression, which contributes to increased pro-inflammatory cytokine expression in the kidney and in tubular cells upon I/R insult; (2) restoration of endogenous H2S production would be of therapeutic value in regulating inflammatory response in I/R-induced kidney injury; (3) tyrosol treatment has a beneficial effect against renal I/R-induced oxidative stress, in part, through its inhibition on NF-B activation and iNOS-mediated NO production. / May 2016
936

Papel dos monócitos inflamatórios na sepse / The role of inflammatory monocytes in sepsis

Cebinelli, Guilherme Cesar Martelossi 12 February 2019 (has links)
Sepse é uma síndrome, na qual, o paciente apresenta lesões de órgãos com risco a vida, em decorrência de uma inflamação exagerada desencadeada por uma infecção. Estima-se uma ocorrência anual de 31,5 milhões de casos de sepse e 19,4 milhões de casos de choque séptico no mundo, causando potencialmente 5,3 milhões de mortes. Esses índices alarmantes fizeram com que em 2017, a Organização Mundial da Saúde (OMS) adotasse uma resolução com o objetivo de aperfeiçoar a prevenção, diagnóstico e tratamento dessa condição clínica que vem sendo negligenciada. A iniciação da sepse, ocorre quando há um descontrole da infecção, acarretando excessiva ativação de células do sistema imune inato. Isso resulta em uma inflamação sistêmica danosa que é responsável pela maioria das alterações fisiopatológicas da sepse. Nesse contexto do sistema imune inato, o papel de neutrófilos já é bem compreendido da patogênese da sepse. Contudo, a função dos monócitos inflamatórios ainda não é bem estabelecida. Ao mesmo tempo que essas células podem participar do controle de infecções, elas também podem contribuir com a inflamação sistêmica e a lesão de órgãos. Deste modo, a compreensão do papel dessas células se faz importante para determinação de novos alvos terapêuticos para essa condição clínica. Nossos resultados demonstraram, em modelo experimental de sepse, que o aumento da emigração de monócitos inflamatórios da medula óssea está relacionado com maior taxa de mortalidade dos animais e exacerbação da inflamação sistêmica. A migração dessas células para órgãos, como rim e pulmão, está relacionado com inflamação e aumento de lesões, nesses locais. Deste modo, conclui-se que monócitos inflamatórios possuem um papel deletério na patogênese da sepse / Sepsis is a syndrome in which the patient has life-threatening organ damage due to an exaggerated inflammation triggered by an infection. The annual occurrence is 31.5 million cases of sepsis and 19.4 million cases of septic shock in the world, which potentially cause 5.3 million deaths. In concern of these alarming reports in 2017, the World Health Organization (WHO) adopted a resolution aimed at improving the prevention, diagnosis and treatment of this neglected clinical condition. The initiation of sepsis occurs when the infection was not controlled, causing excessive activation of the innate immune cells. This excessive activation causes a systemic inflammation that is responsible for most pathophysiological phenomena in sepsis. In this context of the innate immune system, the role of neutrophils is already well understood in the pathogenesis of sepsis. However, the role of inflammatory monocytes is not yet well established. These cells can participate in the control of infections, or can also contribute to systemic inflammation and organs damage. Thus, the understanding of the roles of these cells become important for the development of new therapeutic targets for this clinical condition. Our results demonstrated that the systemic increase of the inflammatory monocytes frequency is related to higher mortality rate, exacerbation of systemic inflammation, increased migration to organs (lung and kidney), and in these sites, are related to inflammation and lesions. Thus, we concluded that these cells have a deleterious role in the pathogenesis of sepsis
937

Etude physiopathologique d'une ichtyose inflammatoire, le "peeling skin disease", à l'aide de deux modèles murins invalidés pour la cornéodesmosine / Pathophysiological study of an inflammatory ichthyosis, the "peeling skin disease", using two corneodesmosin-deficient mouse model

Zaafouri, Sarra 09 October 2017 (has links)
La cornification est la dernière étape de la différenciation terminale de l'épiderme. Elle est caractérisée par de profonds remaniements morphologiques et biochimiques du kératinocyte et aboutit à la formation d'une couche cornée solide, résistante, imperméable et hydratée, responsable de la fonction " barrière " de l'épiderme. Certaines génodermatoses rares, appelées ichtyoses, sont dues à des mutations de gènes impliqués dans la cornification. Le " Peeling Skin Disease " (PSD, OMIM 270300) est une ichtyose inflammatoire généralisée, caractérisée par une importante desquamation, de l'eczéma et un prurit souvent sévère et insomniant. Cette maladie chronique entraine une altération importante de la qualité de vie du patient. A ce jour, aucune thérapie efficace n'est disponible. Le PSD est dû à des mutations homozygotes du gène Cornéodesmosine (CDSN), qui code une protéine adhésive de l'épiderme essentielle à la cohésion du stratum corneum (SC) et à l'homéostasie de la barrière épidermique. La physiopathologie du PSD est encore mal connue. Le décollement du SC conduit à une rupture de la barrière épidermique, qui déclenche à son tour érythème, atopie et prurit, par des mécanismes non élucidés. Afin de décortiquer ces mécanismes, j'ai utilisé deux modèles murins d'invalidation du gène Cdsn (knock-out, KO) dans l'épiderme. Le premier mime le stade précoce du PSD (décollement du SC chez l'embryon E18.5 Cdsnep-/-) et le second, qui est inductible, reproduit le stade chronique (défaut persistant de la barrière épidermique chez la souris adulte Cdsniep-/-). J'ai réalisé l'étude comparative du transcriptome cutané de ces deux modèles à l'aide de puces à ADN. Des signatures d'expression génique distinctes, en lien avec une réponse de restauration de la barrière cutanée, ont été obtenues : induction principalement de gènes de l'inflammation et de la prolifération (Cdsnep-/-) vs des gènes de défenses de l'hôte et de la cornification (Cdsniep-/-). En particulier, une forte expression de gènes codant des inhibiteurs de protéases à cystéine de la famille des stéfines A (cystatine A chez l'homme) et des protéases à sérine de la famille des kallikréines (KLKs), caractérise le modèle adulte Cdsniep-/-. Ceci a été secondairement confirmé dans l'épiderme de patients atteints de PSD. Parmi les KLKs, KLK13 est apparue la plus fortement exprimée, contrairement à KLK5 dont l'expression reste faible et stable. KLK13 pourrait donc intervenir dans la réponse inflammatoire et/ou la desquamation, mécanismes dans lesquels jusqu'à présent seule KLK5 a été décrite comme jouant un rôle central. Une surexpression de KLK13 avait déjà été décrite dans l'épiderme de patients atteints de PSD et au niveau de lésions psoriasiques, ce qui conforte notre hypothèse. Ainsi, mes résultats mettent en lumière KLK13, dont la fonction dans l'épiderme est encore très peu connue. En parallèle, dans le cadre d'un travail collaboratif, j'ai participé à une étude centrée sur la composante inflammatoire de la maladie, réalisée à l'aide de notre modèle de souris adultes Cdsniep-/-. Les résultats obtenus montrent un développement simultané des voies inflammatoires de type Th2 et Th17, ainsi qu'une contre-régulation entre ces deux axes au cours de la maladie chez la souris. En conclusion, mon travail contribue à mieux comprendre les mécanismes physiopathologiques du PSD. Notamment, le modèle adulte Cdsniep-/- apparaît comme particulièrement pertinent pour étudier la maladie humaine. L'exploration du rôle, dans le contexte du PSD, des gènes candidats identifiés pourrait déboucher sur la découverte de nouvelles cibles thérapeutiques. Enfin, nos résultats seront certainement bénéfiques à l'étude d'autres maladies dermatologiques inflammatoires rares (syndrome de Netherton, syndrome SAM) ou fréquentes (psoriasis, dermatite atopique), qui présentent un défaut de barrière épidermique. / Cornification is the final step of epidermal differentiation. It is characterized by structural and biochemical modifications of keratinocytes and leads to the formation of a solid, resistant, impermeable and moisturized cornified layer, responsible for the "barrier" function of the epidermis. Some rare genodermatoses, called ichthyoses, are caused by mutations of genes involved in cornification. The Peeling Skin Disease (PSD, OMIM 270300) is a generalized inflammatory ichthyosis characterized by important desquamation, eczema and severe itching. This chronic disease severely affects patients 'quality of life and no specific therapy is currently available. PSD is due to homozygous mutations in the Corneodesmosin (CDSN) gene, which codes an adhesive epidermal protein crucial for the cohesion of the stratum corneum (SC) and the epidermal barrier homeostasis. The pathophysiology of PSD is still poorly understood. The detachment of the SC leads to an impairment of the epidermal barrier which could in turn trigger erythema, atopic manifestations and pruritus by so far unidentified mechanisms. In order to dissect these mechanisms, I used two epidermis-specific Cdsn-deficient mouse models (knock-out, KO). The first mimics the early phase of PSD (detachment of the SC in Cdsnep-/- E18.5 embryos) and the second, inducible, reproduces the chronic phase (permanent permeability defect in Cdsniep-/- adult mice). I performed a comparative analysis of the skin transcriptome between these two models using DNA microarrays. Distinct molecular signatures related to a skin barrier repair response were highlighted: increased expression of inflammatory and proliferative genes (Cdsnep-/-) vs antimicrobial defense and cornification genes (Cdsniep-/-). In particular, a strong expression of genes coding for inhibitors of cysteine proteases from the stefin A family (cystatin A in humans), and serine proteases of the kallikrein (KLK) family, was distinguishable in Cdsniep-/- mice. This was secondarily confirmed in the epidermis of PSD patients. Among the KLKs, KLK13 was the most strongly up-regulated, contrary to KLK5 whose expression remains low and constant. Thus, KLK13 could take part into the inflammatory response and/or the desquamation when until now only KLK5 was described as playing a central role in these mechanisms. An up-regulation of KLK13 has already been described in the epidermis from PSD patients and from chronic psoriatic plaques, reinforcing our hypothesis. Thus, my results highlight KLK13, whose epidermal function is still poorly characterized. At the same time, I was part of a collaborative study focusing on the inflammatory component of the disease carried out with our Cdsniep-/- adult mouse model. The results showed a simultaneous development of type 2 and type 17 T lymphocytes responses as well as a counter-regulation between these two inflammatory axes. In conclusion, my work contributes to a better understanding of PSD pathophysiology. Notably, the Cdsniep-/- adult mouse model seems especially relevant to study the human disease. A further exploration, in the context of PSD, of the role of the candidate genes we identified could lead to the discovery of new therapeutic targets. Finally, our results will certainly be helpful for the understanding of other inflammatory skin diseases with epidermal barrier defects, whether they are rare (Netherton syndrome, SAM syndrome) or frequent (psoriasis, atopic dermatitis).
938

Regulation of Alloreactive CD8 T Cell Responses by Costimulation and Inflammation

Jangalwe, Sonal 30 June 2017 (has links)
CD8 T lymphocytes are a crucial component of the adaptive immune system and mediate control of infections and malignancy, but also autoimmunity and allograft rejection. Given their central role in the immune system, CD8 T cell responses are tightly regulated by costimulatory signals and cytokines. Strategies targeting signals that are critical for T cell activation have been employed in a transplantation setting to impede alloreactive T cell responses and prevent graft rejection. The goal of my thesis is to understand how costimulatory signals and inflammation regulate alloreactive CD8 T cell responses and how to target these pathways to develop more effective tools to prevent graft rejection. Costimulation blockade is an effective approach to prolong allograft survival in murine and non-human primate models of transplantation and is an attractive alternative to immunosuppressants. I describe a novel murine anti-CD40 monoclonal antibody that prolongs skin allograft survival across major histocompatibility barriers and attenuates alloreactive CD8 T cell responses. I find that the pro-apoptotic proteins Fas and Bim function concurrently to regulate peripheral tolerance induction to allografts. Activation of the innate immune system by endogenous moIecules released during surgery or infections in transplant recipients can modulate T cell responses. However, the direct impact of inflammation on alloreactive CD8 T cell responses is not clear. Using a T cell receptor (TCR) transgenic mouse modeI, I demonstrate that inflammatory stimuli bacterial lipopolysaccharide (LPS) and the viral dsRNA mimetic poly(I:C) differentially regulate donor-reactive CD8 T cell responses by generating distinct cytokine milieus. Finally I demonstrate the role of pro-inflammatory cytokines stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) in improving human B cell development in humanized NOD-scid IL2Rγnull (NSG) mice.
939

Depletion of L2pB1 cells increases abdominal inflammation, blood lipids, and glucose intolerance in DIO mice

Newmark, Jordan Alison 17 June 2016 (has links)
L2pB1 cells are a subset of B-1 B lymphocytes expressing programmed death ligand 2 (PD-L2) on their surface. They constitute 30-50% of B lymphocytes in the mouse peritoneal cavity and contribute to the production of natural IgM antibody. Previous studies have indicated a protective role of B-1 B cells in attenuating atherosclerosis and insulin resistance. We report that L2pB1 cells possess a unique IgM antibody specificity for phosphorylcholine (PC) and phosphatidylcholine (PtC) IgM enabling them to perform PC- and PtC-specific phagocytosis of PtC-nanoparticles. Here we demonstrate that induced depletion of L2pB1 in a transgenic mouse model with L2pB1-specific diphtheria toxin receptor (DTR) expression increases abdominal inflammation in the peritoneal cavity as well as the visceral adipose tissue in diet-induced obese (DIO) mice. L2pB1-depleted DIO mice also display increased triglycerides and blood glucose levels per gram of body weight relative to PBS-injected control DIO mice. Our results suggest that L2pB1 cells may play a role in anti-inflammatory regulation in DIO. Further investigation is required to discover how L2pB1 cells protect from obesity-induced inflammation and whether L2pB1 cells can provide cellular therapy to control chronic inflammation in obese patients. / 2018-06-16T00:00:00Z
940

Perfil inflamatório em gestações com distúrbios hiperglicêmicos: enfoque na análise das vilosidades coriônicas. / Inflammatory profile in pregnancies with hyperglycemic disorders: Focus on analysis of chorionic villi.

Alencar, Aline Paixao 21 October 2015 (has links)
Em diferentes mopdelos, o aumento dos níveis séricos de glicose pode ativar cascatas de sinalização envolvendo receptores semelhantes a Toll, o fator de transcrição NF-kB, moléculas da familia NLRP, ASC e caspase-1, que culminam na produção, ativação e liberação de moléculas inflamatórias. Investigamos o perfil inflamatório sérico e placentário em gestantes com distúrbios glicêmicos e a possível participação da via do inflamassoma NLRP1 e NRLP3 para o estabelecimento desse perfil. Para avaliar o papel da hiperglicemia no estabelecimento desse perfil, a via do inflamassoma foi também estudada em explantes de vilos coriônicos tratados com 100, 200, 300 e 400 mg/dL de glicose. Nossos resultados mostraram aumento na ativação de NF-kB e da expressão de NLRP1, NLRP3, ASC e Caspase-1 nas placentas de gestantes hiperglicemicas e nas culturas tratadas com doses de 300 r 400 mg/dL de glicose. Esses dados sugerem que a ativação da via do inflamassoma na porção fetal da placenta contribui para o processo inflamatório nessas pacientes. / In different models, the increase in serum glucose levels can activate signaling cascades involving Toll-like receptors, the transcription factor NF-kB, NLRP proteins, ASC and caspase-1, which culminate in the production, activation and release of inflammatory molecules . We investigated the serum and placental inflammatory profile in pregnant women with glucose disorders and the possible participation of via the NLRP1 and NRLP3 inflammasome to establish this profile. To evaluate the role of hyperglycemia, molecules of the inflammasome pathway was also studied in explants of chorionic villi treated with 100, 200, 300 and 400 mg / dL glucose. Our results showed an increase in NF-kB activation and expression of NLRP1, NLRP3, ASC and Caspase-1 in placentas of pregnant hyperglycemic women and in cultures treated with 300 and 400 mg / dL glucose. These data suggest that the inflammasome activation of the fetal portion of the placenta contributes to the inflammatory process in these patients.

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