The role of CD28 and CTLA4 in the function and homeostasis of CD4+CD25+ regulatory T cells.

摘要: CD4+CD25+ T cells regulate a variety of autoimmune and alloimmune responses including the development diabetes in non-obese diabetic (NOD) mice. We have examined role CD28/CTLA4/B7 interactions expansion survival regulatory (T(reg)) this setting. CD28/ B7 are essential T(reg) thymus for their periphery. The CD28-mediated homeostasis these is independent Il2, OX40, CD40L, factor Bcl-XI. In addition, analysis from CTLA4-deficient mice suggests that CTLA4 expression not required or function. However, non-activating anti-CTLA4 antibodies blocked suppressor activity vitro. Thus, clinical application co-stimulatory blockade using agents such as CTLA4Ig treatment disease may result complicated outcomes.