UV-enhanced replication of herpes simplex virus in DNA-repair competent and deficient fibroblasts

Abstract Replication of herpes simplex virus type 1 was enhanced in fibroblast cultures when cells were ultraviolet irradiated 12 to 48 hours before infection. Maximum enhancement (340% increase) occurred at exposures of 9.6 J/m 2 in DNA-repair competent fibroblasts. Repair deficient xeroderma pigmentosum cells responded to lower ultraviolet exposures (1.6 to 5.6 J/m 2 ) with lower levels of enhancement (37% to 140%). Ultraviolet irradiation of host cells before infection increased viral DNA synthesis, but did not alter the ability of the cell to adsorb virus. Prostaglandins were not shown to contribute to the process. These results suggest that ultraviolet-enhanced replication of herpes simplex virus may be associated with DNA-repair activities, and that ultraviolet-enhanced herpes simplex virus replication should be further examined for its contribution to herpes simplex virus recurrence in vivo.