The Role of γc Cytokines (IL-2, IL-7, and IL-15) in Regulation of Activation-Induced Cell Death of Memory T Cells

Abstract

The role of γc cytokines (IL-2, IL-7, and IL-15) in the regulation of apoptotic death of memory T cells under cultivation conditions in vitro was studied using the method of cytofluorimetry. It was detected that the effect of IL-2 in combination with TCR activator is aimed at increasing the number of mature CD45RO+CD95+ T cells with a simultaneous decrease in the number of viable T cells, which gives reason to assume the proapoptotic effect of IL-2 under restimulation conditions. On the contrary, the effect of IL-7 and IL-15 in the activation model in vitro leads to an increase in the number of living T cells in СD45RO cultures (as compared with the samples, in which only the activator was added) against the background of an increase in the number of CD8+CD95+ T cells with a central memory phenotype (TCM). Changes induced by IL-15 are aimed an decreasing the content of CD4+CD95+ T cells in CD45RО+ cultures of the immune memory T cells. Thus, a dose-dependent positive effect of IL-2 on the clonal expansion and negative effect on the viability of T cells was demonstrated. While IL-7 and IL-15, on the contrary, preserve the viability of T cells, participating in the generation of a pool of long-lived memory T cells.