Vertical transmission of type 2 herpes simplex virus infection in immunosuppressed hamsters

The effect of immunosuppressive procedure with cyclophosphamide on the vertical transmission of the type 2 herpes simplex virus in hamsters was investigated. Single injection of the cyclophoshamide one day before virus inoculation in various stages of pregnant course caused high rate of placental and fetal infection of the virus. Immunofluorescence technique revealed the presence of viral antigen in more than 90% of placentas and 29% of fetuses with treatment at the middle of late stage of gestation. The drug treatment alone without viral infection brought no detectable changes in placentas or fetuses, whereas slight depletion of mononuclear cells in perifollicular area of the spleen was found. The drug could destroy easily the defense mechanism of the placenta.