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CD4+ T Helper (cd4+ t + helper)
Selected AbstractsAllergic contact dermatitis: the cellular effectorsCONTACT DERMATITIS, Issue 1 2002Ian Kimber Contact hypersensitivity reactions are mediated by lymphocytic effector cells. Until recently it was believed that the most important of these were CD4+ T lymphocytes. However, there is growing evidence that in many instances the predominant effector cell may be a CD8+ T lymphocyte, with in some instances CD4+ cells performing a counter-regulatory function. Here we review the roles of CD4+ T helper (Th) cells and CD8+ T cytotoxic (Tc) cells, and their main functional subpopulations (respectively, Th1 and Th2 cells and Tc1 and Tc2 cells) in the elicitation of contact hypersensitivity reactions and consider the implications of effector cell selectivity for the biology of allergic contact dermatitis. [source] Natural killer T-cell characterization through gene expression profiling: an account of versatility bridging T helper type 1 (Th1), Th2 and Th17 immune responsesIMMUNOLOGY, Issue 1 2008Marcus Niemeyer Summary Natural killer T (NKT) cells constitute a distinct lymphocyte lineage at the interface between innate and adaptive immunity, yet their role in the immune response remains elusive. Whilst NKT cells share features with other conventional T lymphocytes, they are unique in their rapid, concomitant production of T helper type 1 (Th1) and Th2 cytokines upon T-cell receptor (TCR) ligation. In order to characterize the gene expression of NKT cells, we performed comparative microarray analyses of murine resting NKT cells, natural killer (NK) cells and naïve conventional CD4+ T helper (Th) and regulatory T cells (Treg). We then compared the gene expression profiles of resting and alpha-galactosylceramide (,GalCer)-activated NKT cells to elucidate the gene expression signature upon activation. We describe here profound differences in gene expression among the various cell types and the identification of a unique NKT cell gene expression profile. In addition to known NKT cell-specific markers, many genes were expressed in NKT cells that had not been attributed to this population before. NKT cells share features not only with Th1 and Th2 cells but also with Th17 cells. Our data provide new insights into the functional competence of NKT cells which will facilitate a better understanding of their versatile role during immune responses. [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] The Expression of Th1- and Th2-Related Chemokine Receptors in Women with Recurrent Miscarriage: the Impact of Lymphocyte ImmunotherapyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010Nasim Kheshtchin Citation Kheshtchin N, Gharagozloo M, Andalib A, Ghahiri A, Maracy MR, Rezaei A. The Expression of Th1- and Th2-Related chemokine receptors in women with recurrent miscarriage: the impact of lymphocyte Immunotherapy. Am J Reprod Immunol 2010; 64: 104,112 Problem, Recurrent miscarriage (RM) is defined as three or more consecutive pregnancy losses prior to the 20th week of gestation. The aim of this study was to investigate the expression of T helper (Th)1- and Th2-related chemokine receptors on CD4+ T helper and CD8+ T cytotoxic (Tc) cells in RM and control subjects. The effects of lymphocyte immunotherapy on the balance of Th1/Th2 and Tc1/Tc2 chemokine receptors were further evaluated in RM women. Method of study, The expression of Th1-related (CCR5 and CXCR3) and Th2-related (CCR3 and CCR4) chemokine receptors on CD4+ or CD8+ T cells from RM women were analyzed and compared with controls using flow cytometry. The expression of chemokine receptors in RM women was also compared before and after lymphocyte immunotherapy. Results, The ratios of Th1/Th2 and Tc1/Tc2 chemokine receptors were higher in RM women compared to controls. The ratio of Th1/Th2 chemokine receptors was decreased in RM women after immunotherapy, while no significant change was identified in the Tc1/Tc2 after immunotherapy. Conclusion, This study indicates the Th1 dominant immune responses in circulation of RM women compared to controls. Moreover, lymphocyte immunotherapy might influence pregnancy outcome via a shift in the balance of the Th1/Th2 chemokine receptors. [source] | ||||||||||