Effects of IL-12 on the generation of cytotoxic activity in human CD8+ T lymphocytes.

摘要: We have studied the effects of human rIL-12 on proliferation and generation cytotoxic activity in CTL precursors. Purified blood CD8+ T lymphocytes were stimulated overnight with immobilized alpha-CD3 cultured 3 to 4 additional days under various conditions. The addition IL-12 resulted a marked (10- 20-fold), dose-dependent, augmentation cytotoxicity per cell smaller (2-fold) increase number. cells was not inhibited by mAb p55 subunit IL-2 receptor (alpha-Tac) at concentration sufficient block exogenously added IL-2, indicating that did require IL-2. Addition time activation or 1 day later highly effective augmenting cytotoxicity, whereas delayed (day 2 3) no all doses tested synergized low dose inducing differentiation cells. synergistic effect blocked adding neutralizing serum IFN-gamma. In contrast this effect, significantly observed presence higher concentrations (4,500 13,500 pg/ml). An inhibitory also when subsequent This broad set potent responses suggests may play an important immunoregulatory role development vivo be useful tool for manipulating process investigational immunotherapeutic purposes.