HSV-1 infection and immunity in immunosuppressed mice.

The effect of cyclophosphamide (CY) and hydrocortisone (HY) on the susceptibility of mice to intracerebral and intraperitoneal infection with herpes simplex virus type 1 (HSV-1) was investigated. The mean survival time, the survival ration, the localization of HSV-1 antigen in brain, spleen and liver as well as immunity after immunization with inactivated virus were determined. In the case of primary infection, an increased susceptibility to HSV-1 was observed after administration of the immunosuppressive drug. Immunization increased the resistance of mice to virus challenge, but no such effect was observed when the virus challenge, but no such effect was observed when or HY. The influence of CY and HY on the immunization process itself was divergent: when HY was given at the time of immunization, the resistance to virus challenge was abolished. On the other hand, CY given simultaneously with inactivated HSV-1 did not depress the immunization effect.