We have previously demonstrated that the large extracellular loop of the S. mansoni tegument tetraspanin, Sm-TSP-2, when linked to a thioredoxin fusion partner and formulated with Freund's adjuvants, is an efficacious vaccine antigen, eliciting high levels of protection in a murine schistosomiasis model of infection [12]. The gene discussed is THBS2; the disease is schistosomiasis.