Profound Enhancement of the IL-12/IL-18 Pathway of IFN-γ Secretion in Human CD8+ Memory T Cell Subsets via IL-15

摘要: Human memory CD8(+) T cell subsets, termed central and effector cells, can be identified by expression of CD45RA, CD62 ligand (CD62L), CCR7. Accordingly, functional differences have been described for each subset, reflecting unique roles in immunological memory. The common gamma-chain cytokines IL-15 IL-7 shown to induce proliferation differentiation human as well increased functions (i.e., cytokines, cytotoxicity). In this study, we observed that addition or cultures cells profoundly enhanced the IL-12-IL-18 pathway IFN-gamma production. Importantly, lowered threshold concentrations IL-12 IL-18 required induction 100-fold. Comparison demonstrated was superior its ability enhance IL-12-IL-18-induced IFN-gamma, without evidence a synergistic effect between IL-7. We also IL-15- IL-7-mediated enhancement production property cells. Despite lack association division acquisition down-regulation CD62L correlated with IFN-gamma. Purified stimulated down-regulated acquired potent similar Thus, known role development memory, may amplify increasing sensitivity proinflammatory cytokine stimulation.