IL-2 inhibited the generation of CD4+ memory T cells.

The survival of T cells at different stages of development is dependent on extrinsic signals. IL-7 is necessary for the development of memory T cells. IL-7 could induce and maintain the differentiation, survival, and proliferation of CD4(+) memory T cells, and the roles of IL-2 and IL-15 in the generation of CD4(+) memory T cells were still unclear. A CD4(+) memory T cells in vitro generated system by adding IL-7. The phenotype of CD4(+) memory T cells was identified by FACS. The cells proliferation was analyzed by CFSE staining. The involved signal pathways were analyzed by Western blot. We found that IL-2, not IL-15, could inhibit CD4(+) memory T cells generation. Western blot showed that IL-7 up-regulated the P-STAT5A expression and down-regulated Bax expression, IL-2 reduced the effect of IL-7. Besides, IL-2-combined IL-7 up-regulated the P-AKT and Foxo3a expression a little. In conclusion, our data revealed the inhibitory role of IL-2 in CD4(+) memory T cells generation and indicated that PI3K/AKT signal pathway was involved.