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Th Cells (th + cell)
Selected AbstractsEarly and transient ontogenetic expression of the cocaine- and amphetamine-regulated transcript peptide in the rat mesencephalon: Correlation with tyrosine hydroxylase expressionDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2002F. Brischoux Abstract The ontogeny of cocaine- and amphetamine-regulated transcript (CART) expression has been analyzed by immunohistochemistry in the mesencephalon of the rat central nervous system, and compared to the pattern of tyrosine hydroxylase- (TH-) expression. CART-producing neurons were first detected on the embryonic day 11 (E11) in the ventral mesencephalic vesicle. These neurons are among the first cells of the mantle layer to differentiate. From E13, a complementary pattern of distribution was observed, dividing the mantle layer into an external TH zone and an internal CART zone. Many TH-positive neurons were found to migrate from the neuroepithelium through the area containing the CART-immunoreactive neurons to settle more laterally. These TH cells exhibited prominent leading and trailing dendrites in the immediate vicinity of CART perikarya. On E16, the number of CART neurons appeared to diminish, and they were confined near the ventricle and around the fasciculus retroflexus. On E18 and E20, only the Edinger-Westphal nucleus exhibited a strong CART staining as described in the adult brain. Thus, the very early detection of CART during prenatal ontogeny led us to speculate that this peptide might have a role in the development of specific regions of the rat brain. In particular, our observations suggest that CART-expressing neurons might help the migration of the dopaminergic neurons of the substantia nigra. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 221,229, 2002 [source] Age-matched lymphocyte subpopulation reference values in childhood and adolescence: application of exponential regression analysisEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 6 2008Sabine Huenecke Abstract Background:, Normal values of lymphocyte subpopulations for healthy children and adults have been published in defined age groups exclusively, which results in difficult data interpretation for patients close to the limit of contiguous age group ranges. In addition, normal values for a number of lymphocyte subpopulations have not been established to date. Objective:, The aim of this study was to develop a model which provides continuous age-dependent reference values. This model was applied for lymphocyte subpopulations such as naïve and memory T cells as well as their activation profile with diagnostic relevance in children and adults. Study design:, A total of 100 blood samples, obtained from 80 healthy children and 20 adults were analysed by means of four colour-flow cytometry. Continuous age-dependent reference values were computed based on the residual values in an exponential regression model. Results:, We calculated a continuous age-related regression model for both, absolute cell counts and percentages of CD3+CD4+ T helper (TH) cells, CD3+CD8+ cytotoxic T cells, CD56+CD3, natural killer (NK) cells, CD56+CD3+ T cells, CD3+CD4+CD45RA+ naïve TH cells, CD3+CD4+CD45RO+ memory TH cells, CD3+CD8+CD45RA+CD28+ naïve cytotoxic T cells, CD3+CD8+CD45RO+ memory cytotoxic T cells, CD3+CD8+CD69+ early activated cytotoxic T cells and CD3+CD8+HLA-DR+ late activated cytotoxic T cells, respectively, to obtain reference values. Conclusion:, Based on an exponential regression model, the obtained reference values reflect the continuous maturation of lymphocyte subsets during childhood. [source] Autologous nucleus pulposus primes T cells to develop into interleukin-4-producing effector cells: An experimental study on the autoimmune properties of nucleus pulposusJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2009Andrea Geiss Abstract An autoimmune response to herniated nucleus pulposus has been proposed to constitute a pathophysiologic mechanism for inducing sciatica based on the fact that nucleus pulposus under normal conditions is excluded from the development of immunological tolerance. The manifestation of an autoimmune response comprises different steps starting with antigen capture, continuing with activation of T helper (TH) cells and ending with production of autoantibodies. Activated TH cells differentiate into either TH1 cells, predominately producing proinflammatory cytokines such as interferon , (IFN,) or a TH2 subset mainly producing anti-inflammatory cytokines such as interleukin-4 (IL-4). The aim of the present study was to examine if exposure of autologous nucleus pulposus (NP) to the immune system for 3 weeks is potent enough to prime TH cells to differentiate into TH2 cells. The study was performed in a pig model allowing the exposure of NP to the immune system. To assess the polarization of TH cells the intracellular production of IFN, and IL-4 was measured in T cells by using flow cytometry. The revealed predominant production of IL-4 together with low production of IFN, in T cells after NP exposure to the immune system indicates that nucleus pulposus may prime TH cells to develop into IL-4-producing TH2 cells after being exposed to the immune system, for example, in association with disc herniation. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:97,103, 2009 [source] CD31+ Naïve Th Cells Are Stable during Six Months Following Kidney Transplantation: Implications for Post-transplant Thymic FunctionAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2005Peter Nickel Little is known about thymus function in transplant patients. Until recently, the phenotype of T cells that recently emigrated the thymus was unknown. Now it has been demonstrated that CD4+ recent thymus emigrants coexpress CD31 and CD45RA. Here, we investigated whether uremia and immunosuppression influence CD31+ CD45RA+ Th cells before and after kidney transplantation, respectively. Forty-eight renal transplant patients were included receiving either standard triple/quadruple (n = 35) immunosuppression, OKT-3 induction (n = 7) or FTY-720 (n = 6), respectively. Peripheral CD31+ CD45RA+ Th cells were quantified flowcytometrically before and at week 1, 4, 12 and 24 post-transplantation. Thirty-nine healthy adults served as controls. CD31+ CD45RA+ Th cells correlated inversely with age in patients and controls and were comparable in patients before transplantation and age-matched controls. Importantly, CD31+ CD45RA+ Th cell frequencies remained stable during 6 months post-transplantation. In conclusion, CD31+ CD45RA+ Th cells are not significantly altered by uremia before and during 6 months of immunosuppressive therapy after kidney transplantation. Implications for thymus function are discussed. [source] SUMOylation attenuates c-Maf-dependent IL-4 expressionEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 4 2010Bo-Shiou Lin Abstract The function of transcription factors can be critically regulated by SUMOylation. c-Maf, the cellular counterpart of v-maf oncogene, is a potent transactivator of the IL-4 gene in Th2 cells. We found in a yeast two-hybrid screen that c-Maf can interact with Ubc9 and PIAS1, two key enzymes of the SUMOylation pathway. In this study, we report that c-Maf co-localized with these two SUMO (small ubiquitin-like modifier) ligases in the nucleus and that c-Maf can be SUMOylated in vitro and also in primary Th2 cells. We also demonstrated that lysine-33 is the dominant, if not the only, SUMO acceptor site of c-Maf. SUMOylation of c-Maf attenuated its transcriptional activity. Reciprocally, a SUMOylation resistant c-Maf was more potent than WT-c-Maf in driving IL-4 production in c-Maf-deficient Th2 cells. Furthermore, we showed that ablation of the SUMO site did not alter the subcellular localization or the stability of c-Maf protein but instead enhanced its recruitment to the Il4 -promoter. We conclude that SUMOylation at lysine-33 is a functionally critical post-translational modification event of c-Maf in Th cells. [source] Organization and maintenance of immunological memory by stroma nichesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 8 2009Koji Tokoyoda Immunological memory is still one of the enigmas of modern immunology. We poorly understand the generation of memory cells from their precursors, the lifestyle of memory cells or their maintenance, reactivation and termination. Here, we discuss the recent evidence suggesting that memory plasma cells, as defined in this review, and memory Th cells are maintained in the bone marrow, resting (in terms of proliferation) in survival niches organized by dedicated stroma cells, which control the homeostasis of immunological memory. [source] Mouse Th17 cells: Current understanding of their generation and regulationEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2009Chen Dong Abstract IL-17-expressing CD4+ T cells have been recently recognized as a new subset of Th cells, namely Th17 cells. Considerable progress has been made in understanding the developmental regulation of mouse Th17 cells. Here, I summarize this knowledge and discuss on the relationship of Th17 with regulatory and follicular Th cells. [source] Multi-tasking of helper T cellsIMMUNOLOGY, Issue 2 2010Yisong Y. Wan Summary CD4 T helper cells (Th) are critical in combating pathogens and maintaining immune homeostasis. Since the establishment of the Th1,Th2 paradigm in the 1980s, many types of specialized Th cells, including Th1, Th2, Th17, Th9, follicular helper T and regulatory T, have been identified. We have become accustomed to the idea that different Th cells are ,committed' to their paths but recent emerging evidence suggests that under certain conditions, seemingly committed Th cells possess plasticity and may convert into other types of effector cells. In this review, we will first introduce the major sub-types of Th cells that are involved in immune regulation. Then, we will describe in detail the inter-convertibility of Th cells among different sub-types under in vitro and in vivo conditions. Finally, we will discuss our current understanding of the underlying mechanisms on how a particular type of Th cells may convert into other types of Th cells. [source] The CD1d-binding glycolipid ,-galactosylceramide enhances humoral immunity to T-dependent and T-independent antigen in a CD1d-dependent mannerIMMUNOLOGY, Issue 1 2006Gillian A. Lang Summary Specific interaction of class II/peptide with the T-cell receptor (TCR) expressed by class II-restricted CD4+ T helper (Th) cells is essential for in vivo production of antibodies reactive with T-dependent antigen. In response to stimulation with CD1d-binding glycolipid, V,14+ TCR-expressing, CD1d-restricted natural killer T (NKT) cells may provide additional help for antibody production. We tested the hypothesis that the CD1d-binding glycolipid ,-galactosylceramide (,-GC) enhances production of antibodies reactive with T-dependent antigen in vivo. ,-GC enhanced antibody production in vivo in a CD1d-dependent manner in the presence of class II-restricted Th cells and induced a limited antibody response in Th-deficient mice. ,-GC also led to alterations in isotype switch, selectively increasing production of immunoglobulin G2b. Further analysis revealed that ,-GC led to priming of class II-restricted Th cells in vivo. Additionally, we observed that ,-GC enhanced production of antibodies reactive with T-independent antigen, showing the effects of NKT cells on B cells independently of Th cells. Our data show that NKT cells have multiple effects on the induction of a humoral immune response. We propose that NKT cells could be exploited for the development of novel vaccines where protective antibody is required. [source] REVIEW ARTICLE: Th1/Th2/Th17 and Regulatory T-Cell Paradigm in PregnancyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2010Shigeru Saito Citation Saito S, Nakashima A, Shima T, Ito M. Th1/Th2/Th17 and regulatory T-cell paradigm in pregnancy. Am J Reprod Immunol 2010 T-helper (Th) cells play a central role in modulating immune responses. The Th1/Th2 paradigm has now developed into the new Th1/Th2/Th17 paradigm. In addition to effector cells, Th cells are regulated by regulatory T (Treg) cells. Their capacity to produce cytokines is suppressed by immunoregulatory cytokines such as transforming growth factor (TGF)-, and interleukin (IL)-10 or by cell-to-cell interaction. Here, we will review the immunological environment in normal pregnancy and complicated pregnancy, such as implantation failure, abortion, preterm labor, and preeclampsia from the viewpoint of the new Th1/Th2/Th17 and Treg paradigms. [source] CD31+ Naïve Th Cells Are Stable during Six Months Following Kidney Transplantation: Implications for Post-transplant Thymic FunctionAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2005Peter Nickel Little is known about thymus function in transplant patients. Until recently, the phenotype of T cells that recently emigrated the thymus was unknown. Now it has been demonstrated that CD4+ recent thymus emigrants coexpress CD31 and CD45RA. Here, we investigated whether uremia and immunosuppression influence CD31+ CD45RA+ Th cells before and after kidney transplantation, respectively. Forty-eight renal transplant patients were included receiving either standard triple/quadruple (n = 35) immunosuppression, OKT-3 induction (n = 7) or FTY-720 (n = 6), respectively. Peripheral CD31+ CD45RA+ Th cells were quantified flowcytometrically before and at week 1, 4, 12 and 24 post-transplantation. Thirty-nine healthy adults served as controls. CD31+ CD45RA+ Th cells correlated inversely with age in patients and controls and were comparable in patients before transplantation and age-matched controls. Importantly, CD31+ CD45RA+ Th cell frequencies remained stable during 6 months post-transplantation. In conclusion, CD31+ CD45RA+ Th cells are not significantly altered by uremia before and during 6 months of immunosuppressive therapy after kidney transplantation. Implications for thymus function are discussed. [source] Lipoteichoic acid from Staphylococcus aureus enhances allergen-specific immunoglobulin E production in miceCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2003K. Matsui Summary Background Our previous study demonstrated that lipoteichoic acid (LTA) from Staphylococcus aureus induced T helper type 2 (Th2)-prone dermatitis resembling that seen in atopic dermatitis (AD) patients in mice sensitized percutaneously with an allergen. However, the effects of LTA on allergen-specific IgE production in such sensitized mice have not been elucidated. Objective The purpose of this study was to determine the effects of LTA from S. aureus on allergen-specific IgE production in mice sensitized percutaneously with a house dust mite antigen (MA). Methods Mice were sensitized with a single topical application of MA and/or LTA to barrier-disrupted abdominal skin. One to 5 weeks later, MA-specific IgE antibodies in sera from sensitized mice were detected by an enzyme-linked immunosorbent assay (ELISA). Expression of B7.1 (CD80), B7.2 (CD86) and CD40L molecules by CD40-positive (CD40+) and CD4-positive (CD4+) cells in the lymph nodes of sensitized mice were analysed by flow-cytometry (FACS). Results Simultaneous sensitization with MA and LTA increased IgE production 3 weeks later, significantly more than sensitization with MA alone. FACS analysis of CD40+ cells in the lymph nodes from sensitized mice showed that simultaneous sensitization with MA and LTA did not enhance CD80- or CD86-expression by antigen-presenting cells such as B lymphocytes and dendritic cells more than sensitization with MA alone. However, analysis of CD4+ cells in the lymph nodes showed that simultaneous sensitization with MA and LTA increased the number of CD40L-expressing Th cells more than sensitization with MA alone. Conclusion These results suggest that LTA enhances allergen-specific IgE production by a mechanism associated with up-regulation of CD40L-expressing Th cells and this might explain the role of skin colonization with S. aureus in AD patients. [source] Relationship between changes in interferon-, production by peripheral blood T cells and changes in peak expiratory flow rate in patients with chronic stable asthmaCLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2002Y. I. Koh Summary Background Cytokines production by T helper lymphocytes (Th cells), which orchestrate the interplay of the different cells involved in airway inflammation of asthma, may be reflected in peripheral blood. Some studies have suggested that the Th cell cytokines by peripheral blood T cells correlate with asthma severity. Objective To investigate the relationship between changes in IFN-, production by peripheral blood T cells and changes in lung function in chronic stable asthmatics. Methods Sixteen patients with chronic stable moderate asthma aged 35,65 years (nine women) were recruited. Morning and evening peak expiratory flow rates (PEFR) monitoring and blood sampling for peripheral blood T cell culture, total IgE and blood eosinophils were performed at baseline and week 12. Levels of IFN-,, IL-4 and IL-5 in culture supernatants of peripheral blood T cell were determined by using enzyme-linked immunosorbent assay (ELISA) kits. Results Patients with increased IFN-, changes from baseline showed significantly increased changes in morning (P = 0.02) and evening (P < 0.05) PEFR compared with those with decreased IFN-, changes. The changes in IFN-, production and IFN-,: IL-4 ratio significantly correlated with the changes in morning PEFR (Rs = 0.59, P < 0.02; Rs = 0.63, P < 0.01, respectively) and tended to correlate with the changes in evening PEFR (Rs = 0.45, P = 0.08; Rs = 0.5, P = 0.05, respectively). The changes in IL-4 and IL-5 did not correlate with the changes in IgE and blood eosinophils, respectively. Conclusions These findings suggest that IFN-, may be associated with the alteration of lung function in asthmatics and play a role in the pathophysiology of chronic stable asthma. [source] Assessing immune function in adult bronchiectasisCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2006P. T. King Summary Bronchiectasis is characterized by chronic airway infection and damage and remains an important health problem. Recent literature has emphasized the role of host defence and immune deficiency in the pathogenesis of bronchiectasis, but there have been few studies of immune function in adult bronchiectasis. A comprehensive screen of immune function was conducted in 103 adult patients with bronchiectasis, encompassing full blood examinations, immunoglobulins and IgG isotypes, complement levels, lymphocyte subsets and neutrophil function. Full blood examinations were normal in this cohort, as were complement levels. Statistical analysis confirmed that a significant number of subjects had low levels of IgG3 (13 patients), B cell lymphocytes (six patients) and T helper cell lymphocytes (seven patients) when compared with controls (P < 0·05). The most common abnormality was found with testing of the neutrophil oxidative burst. All subjects had a normal neutrophil phagocytic function but 33 of the subjects had an oxidative burst that was below the normal range (P < 0001). Almost half the group (45 subjects) had abnormally low levels of one of these four parameters. The findings of low B cells, Th cells and oxidative burst in bronchiectasis are novel. The results emphasize the importance of immune function assessment for adult bronchiectasis. [source] Proinflammatory cytokines (IL-17, IL-6, IL-18 and IL-12) and Th cytokines (IFN- ,, IL-4, IL-10 and IL-13) in patients with allergic asthmaCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 2 2001C. K. Wong Allergen-reactive T helper type-2 (Th2) cells and proinflammatory cytokines have been suggested to play an important role in the induction and maintenance of the inflammatory cascade in allergic asthma. We compared the plasma concentrations of novel proinflammatory cytokines IL-17 and IL-18, other proinflammatory cytokines IL-6 and IL-12, Th2 cytokines IL-10 and IL-13, and intracellular interferon- , (IFN- ,) and IL-4 in Th cells of 41 allergic asthmatics and 30 sex- and age-matched health control subjects. Plasma cytokines were measured by enzyme-linked immunosorbent assay. Intracellular cytokines were quantified by flow cytometry. Plasma IL-18, IL-12, IL-10, IL-13 concentrations were significantly higher in allergic asthmatic patients than normal control subjects (IL-18: median 228·35 versus 138·72 pg/ml, P < 0·001; IL-12: 0·00 versus 0·00 pg/ml, P = 0·001; IL-10: 2·51 versus 0·05 pg/ml, P < 0·034; IL-13: 119·38 versus 17·89 pg/ml, P < 0·001). Allergic asthmatic patients showed higher plasma IL-17 and IL-6 concentrations than normal controls (22·40 versus 11·86 pg/ml and 3·42 versus 0·61 pg/ml, respectively), although the differences were not statistically significant (P = 0·077 and 0·053, respectively). The percentage of IFN- , -producing Th cells was significantly higher in normal control subjects than asthmatic patients (23·46 versus 5·72%, P < 0·001) but the percentage of IL-4 producing Th cells did not differ (0·72 versus 0·79%, P > 0·05). Consequently, the Th1/Th2 cell ratio was significantly higher in normal subjects than asthmatic patients (29·6 versus 8·38%, P < 0·001). We propose that allergic asthma is characterized by an elevation of both proinflammatory and Th2 cytokines. The significantly lower ratio of Th1/Th2 cells confirms a predominance of Th2 cells response in allergic asthma. [source] |