Comparative replication of HSV-1 in BALB/c and C57BL/6 mouse embryo fibroblasts in vitro.

Herpes simplex virus type 1 (HSV)-host cell interactions were studied in fibroblasts from inbred mice by measuring virus replication, virus adsorption, infectious center formation, and single-cell virus production. BALB/c mouse embryo fibroblasts (MEF) produced more intracellular and extracellular virus than C57BL/6 MEF, with differences in virus production first appearing at 16 hr after inoculation. Virus yield in C57BL/6 cells peaked earlier (16 hr) and at a lower level than in BALB/c cells (20 hr). These results were explained by a difference in single-cell virus replication, rather than less efficient adsorption or the presence of cells that could not be infected. Host-related variation in the ability of infected cells to support HSV replication may account, in part, for differences in the severity of HSV ocular disease.