کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9261668 1214314 2005 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Thymic regulatory T cells
موضوعات مرتبط
علوم زیستی و بیوفناوری ایمنی شناسی و میکروب شناسی ایمونولوژی
پیش نمایش صفحه اول مقاله
Thymic regulatory T cells
چکیده انگلیسی
Recently, small subsets of CD4+CD25+ and of CD8+CD25+ cells sharing similar characteristics have been detected in human fetal and post-natal thymuses. Both CD4+CD25+ and CD8+CD25+ human thymocytes express Foxp3 and GITR mRNA, as well as surface CCR8 and TNFR2 and cytoplasmic CTLA-4 proteins, which are common features of mature Treg cells. Following activation they do not proliferate or produce cytokines, but express surface CTLA-4 and TGF-β1. They suppress the proliferation of autologous CD4+CD25− thymocytes to allogeneic stimulation by a contact-dependent mechanism related to the combined action of surface CTLA-4 and TGF-β leading to the inhibition of the IL-2R α chain on target T cells. Lastly, both CD4+CD25+ and CD8+CD25+ Treg thymocytes exert strong suppressive activity on Th1, but much lower on Th2 cells, since these latter may escape from suppression via their ability to respond to growth factors other than IL-2. Treg cells that develop in, and emerge from, the thymus are certainly responsible for the maintenance of self-tolerance and prevention of autoimmune disorders. The result that Th1 cells are highly susceptible to the suppressive activity of Treg thymocytes is consistent with the important role of these cells in protecting against the Th1-mediated immune response to autoantigens.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Autoimmunity Reviews - Volume 4, Issue 8, November 2005, Pages 579-586
نویسندگان
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