Cutting Edge: CTLA-4 Ligation Delivers a Unique Signal to Resting Human CD4 T Cells That Inhibits Interleukin-2 Secretion but Allows Bcl-XL Induction

摘要: We have assessed the functional effects of a panel CTLA-4 mAbs on resting human CD4 + T cells. Our results demonstrate that some can inhibit proliferative responses cells and cell cycle transition from G 0 to 1 . The inhibitory were evident within 4 h, at time when surface expression remained undetectable. Other had no detectable effects, indicating binding Ab alone is not sufficient mediate down-regulation responses. Interestingly, while IL-2 production was shut off, anti-CTLA-4 permitted induction survival gene bcl-X L Consistent with this observation, viable apoptosis detected after ligation.