Sm-p80-based DNA vaccine formulation induces potent protective immunity against Schistosoma mansoni

Abstract

No effective vaccine exists for the human parasitic disease, schistosomiasis. We have targeted a functionally important antigen, Sm‐p80 as a vaccine candidate because of its consistent immunogenicity, protective potential and important role in the immune evasion process. In this study we report that a Sm‐p80‐based DNA vaccine formulation confers 59% reduction in worm burden in mice. Animals immunized with Sm‐p80‐pcDNA3 exhibited a decrease in egg production by 84%. Sm‐p80 DNA elicited strong immune responses that include IgG2A and IgG2B antibody isotypes in vaccinated animals. Splenocytes proliferated in response to Sm‐p80 produced appreciably more Th1 response enhancing cytokines (IL‐2, IFN‐γ) than Th2 response enhancing cytokines (IL‐4, IL‐10). These data reinforce the potential of Sm‐p80 as an excellent vaccine candidate for schistosomiasis.