Role of coexpression of IL-2 and herpes simplex virus proteins in recombinant vaccinia virus vectors on levels of induced immunity.

Vaccinia virus recombinants co-expressing the genes for IL-2 and HSV-1 gC or gD were used to study the potential adjuvant effects of IL-2 on immunity to HSV-1. In addition, constructs were produced which, while expressing IL-2, encoded for reduced levels of HSV-1 gC. Studies with mice revealed that gC and gD could stimulate HSV-1 immunity as measured by neutralizing antibody (NA), lymphoproliferation and viral clearance. IL-2 enhancement of NA and lymphoproliferation was observed only in those groups of mice immunized with the sub-optimal gC construct which co-expressed IL-2. In no instance did the presence of IL-2 augment the ability of mice to clear an epithelial challenge of HSV-1.