Antibody responses against HIV in rhesus macaques following combinations of mucosal and systemic immunizations with chimeric alphavirus-based replicon particles.

Mucosal and systemic transmission of HIV is prevalent. Therefore, mucosal followed by parenteral immunizations with chimeric vs. complete alphavirus-based replicon particles, encoding an HIV envelope glycoprotein, were tested. Female rhesus macaques were immunized intranasally and then intramuscularly. Following the immunizations, enhanced mucosal and systemic antibody responses were detected with the chimeric compared to the complete replicon particles. Although similar proportions of the same peripheral blood monocyte lineage target cells were infected with the chimeric vs. the complete replicon particles, the latter resulted in enhanced expression of the gene of interest, suggesting a possible mechanism of the enhanced immunogenicity.