Cytopathic effects induced by Epstein-Barr virus replication in epithelial nasopharyngeal carcinoma hybrid cells.

NPC-KT cl.S61, a subclone derived from an epithelial-nasopharyngeal carcinoma hybrid cell line (NPC-KT), showed cytopathic changes characteristic of herpesvirus replication, including formation of multinucleated giant cells and inclusion bodies, when Epstein-Barr virus replicative cycle was induced by 5-iodo-2'-deoxyuridine. Acyclovir (an inhibitor of herpesvirus DNA polymerase), Epstein-Barr virus-immune human serum, or 2-deoxyglucose (an inhibitor of the glycosylation) interfered with syncytium formation, indicating that a virus-specified glycoprotein belonging to the late group is responsible for cell fusion induced by Epstein-Barr virus replication in cl.S61 cells.