Alloimmunity: Cytokines, CTLA-4, CD25 Physiological Mechanisms of Regulating
نویسندگان
چکیده
منابع مشابه
Physiological mechanisms of regulating alloimmunity: cytokines, CTLA-4, CD25+ cells, and the alloreactive T cell clone size.
The mechanisms underlying physiological regulation of alloimmune responses remain poorly defined. We investigated the roles of cytokines, CTLA-4, CD25(+) T cells, and apoptosis in regulating alloimmune responses in vivo. Two murine cardiac transplant models were used, B10.D2 (minor mismatch) and C57BL/6 (major mismatch), into BALB/c recipients. Recipients were wild type, STAT4(-/-) (Th1 deficie...
متن کاملTargeted CTLA-4 engagement induces CD4+CD25+CTLA-4high T regulatory cells with target (allo)antigen specificity.
CTLA-4 (CD152) is actively involved in down-regulating T cell activation and maintaining lymphocyte homeostasis. Our earlier studies showed that targeted engagement of CTLA-4 can down-modulate T cell response and suppress allo- and autoimmune responses. In this study, we report that targeted CTLA-4 engagement can induce immune tolerance to a specific target through selective induction of an Ag-...
متن کاملHuman CD8+CD25+ thymocytes share phenotypic and functional features with CD4+CD25+ regulatory thymocytes.
CD8+CD25+ cells, which expressed high levels of Foxp3, glucocorticoid-induced tumor necrosis factor receptor (GITR), CCR8, tumor necrosis factor receptor 2 (TNFR2), and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) mRNAs, were identified in the fibrous septa and medullary areas of human thymus. Activated CD8+CD25+ thymocytes did not produce cytokines, but most of them expressed surface C...
متن کاملPhenotype, Localization, and Mechanism of Suppression of CD4+CD25+ Human Thymocytes
Phenotypic markers, localization, functional activities, and mechanisms of action in vitro of CD4(+)CD25(+) T cells, purified from postnatal human thymuses, were investigated. These cells showed poor or no proliferation in mixed lymphocyte culture (MLC), and suppressed in a dose-dependent fashion the proliferative response to allogeneic stimulation of CD4(+)CD25(-) thymocytes. Virtually all CD4...
متن کاملRole of CD8+ regulatory T cells in organ transplantation
CD8(+) T cells are regulatory T cells (Tregs) that suppress both alloimmunity and autoimmunity in many animal models. This class of regulatory cells includes the CD8(+)CD28(-), CD8(+)CD103(+), CD8(+)FoxP3(+) and CD8(+)CD122(+) subsets. The mechanisms of action of these regulatory cells are not fully understood; however, the secretion of immunosuppressive cytokines, such as interleukin (IL)-4, I...
متن کامل