The Cord Blood T cell Proliferation and Apoptosis: Influence of Interleukin-2, -4, -7 and Dexametasone.

We have shown that the severity of newborns' clinical condition is accompanied by two independent deviations in functional properties of T cells: week proliferative response to activation through CD3 molecule and high sensitivity to apoptosis. Studies of effects exerted by recombinant interleukins and dexamethasone upon cord blood mononuclear cell (CBMC) apoptosis proves that the IL-2, -4 and -7 deficiency is common to enhance apoptosis in CBMC cultures of newborn infants. However, interleukin deficiency is not the sole cause of high level of CBMC apoptosis, and some other factors are required, which may determine the cell sensitivity towards apoptosis. The weakness of proliferative response of T cells to activation seems to be determined rather by the effect of suppressive factors, production of which can be blocked by dexamethasone, than by the death of activated cells in apoptosis.