Abstract: A helminth protein immunogen is described. Included as the immunogen is an isolated protein comprising an immunogenic, extracellular fragment of a schistosome tegument protein selected from the group consisting of a TSP-1 protein; a TSP-2 protein; and a 7TM protein. An antibody which binds the isolated protein is also described. Additionally, an immunotherapeutic composition comprising the immunogenic protein and an immunologically acceptable carrier, diluent or excipient is described. Furthermore, a vaccine comprising the immunogenic protein is described. Also described are an isolated nucleic acid that encodes the immunogenic protein and a genetic construct comprising that isolated nucleic acid. Further, a host cell comprising the genetic construct is described. A method of immunizing against schistosomiasis including the step of administering the immunotherapeutic composition to an animal is also described.