Lytic replication of Human herpesvirus 8 and induction of apoptosis.

Although many viruses can induce apoptosis in infected cells, large DNA viruses, such as poxviruses, herpesviruses and adenoviruses, usually exhibit the ability to suppress the induction of apoptosis in the infected cells. We investigated the ability of Human herpesvirus 8 (HHV-8) to protect cells from apoptosis induced by the virus. HHV-8 has been shown to harbor genes with anti-apoptotic capacity. However, we demonstrate here that a lytic replication of HHV-8 resulted in induction of apoptosis using different techniques to detect apoptosis. Therefore, despite the presence of anti-apoptotic genes in its genome, HHV-8 could complete its cycle of productive infection while inducing apoptosis in infected cells. This finding might have implications for the pathobiology of HHV-8 and other gamma herpesviruses in vivo.