EFFECTS OF γс-CYTOKINES (IL-2, IL-7 AND IL-15) UPON IN VITRO MATURATION AND DIFFERENTIATION OF CD4+CD45RО+/CD8+CD45RО+ T CELLS

Effect of γс-cytokines (IL-2, IL-7 и IL-15) upon maturation and differentiation of cytotoxic and helper CD45RО+ Tcell population was studied in the homeostatic in vitro culture conditions. We have found that IL-2, IL-7 and IL-15 mediate maturation and differentiation of CD8 T cells central memory, replenishing the population of cells that exhibit effector functions. Action of IL-2 on CD4+ central memory T cells is accociated with generation of effector memory cells by reducing the number of immature effectors (CD62L–CD27+), whereas IL-7 promotes the formation of immature (CD62L–CD27+) effectors. IL-2, IL-7 and IL-15 initiate formation of terminally-differentiated cells in a subpopulation of CD8+CD45RO+ lymphocytes, providing a stable immunological memory to a pathogen reinfestation.