Activation of lymphocytes by varicella-zoster virus (VZV): expression of interleukin-2 receptors on lymphocytes cultured with VZV antigen.

The expression of human leukocyte antigen (HLA-DR) and interleukin-2 receptor (IL-2R; alpha and beta subunits) was significantly increased in peripheral blood mononuclear cells (PBMC) from varicella-zoster virus (VZV)-seropositive donors when PBMC were cultured with VZV antigen for 6 days. The increased expression of HLA-DR and IL-2R was observed in both CD4+ and CD8+ lymphocytes, which suggests that both types of lymphocytes from VZV-seropositive donors were activated when PBMC were cultured with VZV antigen. Adding anti-IL-2R alpha did not inhibit lymphocyte proliferation in response to VZV antigen, although marked inhibition was obtained by adding anti-IL-2R beta. No IL-2 was detected in the supernatant of PBMC cultured with VZV antigen; however, antibody to IL-2 inhibited lymphocyte proliferation on exposure to VZV antigen. These results indicate that IL-2 and expression of IL-2R beta are essential to lymphocyte activation by VZV antigen.