Induction of humoral and cellular immune responses in mice by HIV-derived infectious pseudovirions.

ABSTRACT

Infectious pseudovirions based on HIV show the morphology of the parent virus and a genome that is partially expressed in infected cells. The constructs are capable of a single round of infection. In this study, we generated vesicular stomatitis virus (VSV) glycoprotein (G) pseudotyped HIV-1-derived pseudovirions that contain a codonoptimized p17/p24 HIV-1 gag or the green fluorescent protein (GFP) gene as transgene. BALB/c mice were immunized in a DNA prime pseudovirion boost fashion. Immunization induced a Gag-specific antibody response, high titers of neutralizing antibodies directed against the VSV-G protein and a Gag-specific IFN-gamma-secreting cytotoxic T lymphocyte (CTL) response. CTL responses were induced by both structural proteins contained in the pseudovirion preparation and through expression of the transgene. Infection properties similar to those of live attenuated HIV and the immunogenicity observed make infectious pseudovirions valuable tools to further study the mechanism of immune stimulation in models of HIV infection.