Alteration of the growth of cytomegalovirus and herpes simplex virus type 1 by epidermal growth factor, a contaminant of crude human chorionic gonadotropin preparations.

Pretreatment (12-48 h) of human fibroblasts with crude, human chorionic gonadotropin (HCG) was found to suppress cytomegalovirus infection and enhance productive herpes simplex type 1 (HSV) infection in vitro. Maximal effect on virus replication occurred at the time of maximal infectivity of control cultures (48 h and 6 days after viral innoculation for HSV and cytomegalovirus, respectively). The alteration in viral growth was not due to the HCG itself, but rather to epidermal growth factor, a contaminant of crude HCG. The effect of epidermal growth factor on viral infectivity was shown to be a cell-mediated event requiring protein synthesis.