Differential Sensitivity of Naive and Memory CD8+T Cells to Apoptosis in Vivo

摘要: Apoptosis is a critical regulator of homeostasis in the immune system. In this study we demonstrate that memory CD8+ T cells are more resistant to apoptosis than naive cells. After whole body irradiation mice, both and decreased number, but reduction number was 8-fold greater addition examining radiation-induced apoptosis, analyzed expansion contraction vivo following exposure Ag. We found not only responded quickly after viral infection, secondary effector generated from underwent much less compared with primary effectors (3- 5-fold vs 10- 20-fold decrease). Increased numbers were observed lymphoid non-lymphoid tissues. When transferred into same animal, These experiments analyzing animal show unequivocally downsizing response reflects an intrinsic property simply due environmental effects. findings have implications for designing prime/boost vaccine strategies also optimizing immunotherapeutic regimens treatment chronic infections.