Immunity induced by DNA immunization with herpes simplex virus type 2 glycoproteins B and C

The complete sequence of herpes simplex virus type 2 (HSV-2) glycoproteins B and C (gB & gC) were cloned into plasmid expression vectors and evaluated in murine and guinea pig genital HSV-2 models. Balb/c mice were immunized with either pgB-2 or pgC-2 plasmids intramuscularly (IM) or intradermally ( ID). The vaccines induced HSV-2-specific neutralizing and ELISA IgG antibod y, but little or no enhancement of viral clearance from the vagina was dete cted following intravaginal challenge. Immunization of guinea pigs with pgB -2 or pgC-2 induced ELISA IgG antibody; however, antibody titers were appro ximately one log(10) unit lower than that seen in HSV-2 convalescent sera. Ih? immunization of guinea pigs with either plasmid also did not decrease v aginal viral shedding following vaginal challenge, but the severity of the acute disease and the subsequent number of recurrent lesion days were reduc ed in animals immunized with pgB-2. Lastly, IM immunization of latently inf ected guinea pigs with a combined gB-2 and gC-2 plasmid vaccine significant ly reduced the number of subsequent HSV-7 recurrences. DNA vectors expressi ng gB-2 or gC-2 were both immunogenic, although the gB-2 plasmid induced hi gher titers of antibody and significantly reduced primary and recurrent her petic disease in the guinea pig model. These results also suggest that immu notherapy with plasmid expression vectors may be effective against recurren t genital HSV-2 disease. (C) 1999 Elsevier Science Ltd. All rights reserved .