Progression of intravaginal infection by herpes simplex-2 in genetically athymic mice

The purpose of this paper was to study the pathogenesis of wild-type Herpes simplex-2 (HSV-2) primary intravaginal (IVAG) infection in genetically athymic (nude) mice. Nude (nu/nu) N: NIH(S) and Balb/c mice, as well as their euthymic counterparts were IVAG infected with 5 x 10(5) pfu of HSV-2. The progression of the infection was followed by HSV-2 immunolabeling using the peroxidase-antiperoxidase technique in tissue sections of the whole body, electron microscopy, and viremia titration at two different time points. 70% of athymic NIH mice, 30% of euthymic NIH mice, and 80% of both athymic and euthymic Balb/c mice developed acute vulvovaginitis and died between 8-10 days post-infection (pi). Viremia was not detected in either athymic or euthymic mice. HSV-2 replicated in the vulvovaginal, vesical and perianal epithelia, then progressed towards the central nervous system mainly along autonomic nerves and ganglia. HSV-2 antigens were not detected in liver, spleen, kidney, skin, heart, lung or bone marrow. The conclusion is that the T-cell immune response seems to limit the IVAG infection of NIH mice at the inoculation site, but is not involved in preventing HSV-2 dissemination through the blood.