Immune responses in mice induced by HSV-1 glycoproteins presented with ISCOMs or NISV delivery systems

The purpose of this study was to evaluate the immunogenicity of a herpes simplex virus type 1 (HSV-1) antigen preparation, obtained following zwitterionic detergent treatment of virus, and incorporation of the antigens into either immunostimulating complexes (ISCOMs) or non-ionic surfactant vesicles (NISV) delivery systems. Using Balb/c mice the ISCOM and NISV HSV-1 vaccines were assayed for their capacity to induce and enhance both the humoral and cellular immune responses, and to elicit protection against both homologous and heterologous virus challenge. The serum from animals vaccinated with either the NISV or the ISCOM HSV-1 antigen preparation, were found to contain high levels of total IgG and IgG1 and IgG2a subclass antibodies. In addition, both preparations were found to induce high neutralizing (NT) antibody levels following a two immunization protocol and to provide some protection against homologous and heterologous HSV challenge infection. Lymphoproliferative responses were observed in cultures of splenocytes from mice immunized with both HSV-1 NISV vaccine and HSV-1 ISCOMs vaccine, following various antigenic stimuli in vitro. In general, these were most marked in animals immunized with the HSV-1 NISV preparation, and particularly so when the splenocytes were stimulated in vitro with live HSV-1. Both the NISV and ISCOM HSV-1 vaccines were found to have induced interleukin 2, interleukin 10 and interferon-γ in spleen cell culture supernatants, although again, the highest responses in general were observed in supernatant fluids from spleen cell cultures from animals immunized with the HSV-1 NISV preparation. These results suggest that a wide range of immune activity can be elicited by HSV-1 antigens presented to the immune system of mice in these formulations.