CONSTRUCTION AND CHARACTERIZATION OF A REPLICATION-DEFECTIVE HERPES-SIMPLEX-VIRUS-2 ICP8-MUTANT STRAIN AND ITS USE IN IMMUNIZATION STUDIES IN A GUINEA-PIG MODEL OF GENITAL-DISEASE
Xj. Dacosta et al., CONSTRUCTION AND CHARACTERIZATION OF A REPLICATION-DEFECTIVE HERPES-SIMPLEX-VIRUS-2 ICP8-MUTANT STRAIN AND ITS USE IN IMMUNIZATION STUDIES IN A GUINEA-PIG MODEL OF GENITAL-DISEASE, Virology, 232(1), 1997, pp. 1-12
A replication-defective mutant of herpes simplex virus 2 (HSV-2) was e
ngineered by replacing the ICP8 gene of HSV-2 strain 186 with an ICP8-
lacZ fusion gene from the herpes simplex virus 1 (HSV-1) HD-2 mutant s
train. The resulting virus, HSV-2 5BlacZ, is defective for growth in V
ero cells but is capable of growth in a cell line that expresses HSV-1
ICP8. In Vero cells, the mutant virus is defective for DNA synthesis
but is able to express many viral proteins at levels similar to those
of wild-type virus, including several of the late kinetic class. SDS-P
AGE and Western blot analysis demonstrated the expression of glycoprot
eins B and D by 5BlacZ in Vero cells. Initial studies have shown that
immunization with 5BlacZ protects guinea pigs from intravaginal HSV-2
challenge. Immunized animals had less severe genital skin disease and
reduced replication of the challenge virus in the genital tract during
primary infection and reduced episodes of recurrent disease. Thus, HS
V-2 ICP8 shows gene regulatory properties similar to those of HSV-I IC
P8, and this HSV-2 ICP8 mutant virus shows a phenotype similar to thos
e of HSV-1 ICP8 mutant strains. Replication-defective mutants of HSV-2
offer a potential vaccine approach for immune intervention against HS
V-2 genital disease and latent infection. (C) 1997 Academic Press.