| surface antigens of and cross-protection between two geographical isolates of schistosoma mansoni. | two isolates of schistosoma mansoni from puerto rico and egypt were examined to determine if there were differences in surface antigens of the schistosomulum and to assess the ability of the two isolates to induce protection against one another in vivo. immune mouse and human patient antisera recognized the same antigens on the schistosomulum surface of both isolates. however, mice immunized with schistosomula-released products from the egyptian isolate recognized an additional antigen of mr 13k ... | 1987 | 3108832 |