FAS ANTIGEN AND BCL-2 EXPRESSION ON LYMPHOCYTES CULTURED WITH CYTOMEGALOVIRUS AND VARICELLA-ZOSTER VIRUS-ANTIGEN

Fas antigen and bcl-2 expression on peripheral blood mononuclear cells (PBMC) cultured with cytomegalovirus (CMV) and varicella-zoster virus (VZV) antigen was analyzed by three-color flow cytometry. Expression of Fas antigen increased significantly in CD45RO(+) populations of both CD4(+) and CD8(+) cells obtained from CMV and VZV seropositive donors after culture with CMV and VZV antigen for 6 days. Fas antigen expression did not increase in PBMC cultured with control antigen. In contrast, bcl-2 expression decreased both in CD4(+)CD45RO(+) and CD8(+)CD45RO(+) cells from the same donors. Fas antigen and bcl-2 expression in CD45RA(+) populations did not change. Cell viability of cultured cells with CMV and VZV antigen decreased after treatment with anti-Fas antibody and DNA fragments indicating apoptosis were detected in the cell lysate of these cultured cells after treatment with anti-Fas antibody. These data suggest that Fas antigen and bcl-2 protein may interact in regulating the cell death process of activated memory lymphocytes and eliminating lymphocytes activated by viral infection. (C) 1995 Academic Press, Inc.