Schistosoma mansoni: identification, characterization, and purification of the spine glycoprotein by monoclonal antibody

A tegumental surface membrane antigen of Schistosoma mansoni has been identified by use of a monoclonal antibody. The binding of ¹²⁵I-labeled monoclonal antibody showed that proteins sharing antigenic determinants recognized by this monoclonal antibody were present in cercariae and worms of both sexes, but were absent from schistosome egg extract. The protein molecules expressing these antigenic determinants differed in molecular weight: 120,000 in cercaria and 170,000 in male and female worms. The cercarial glycoprotein immunoprecipitated with the monoclonal antibody was also immunoprecipited by sera of infected humans, as shown by two-dimensional gel electrophoresis and tryptic peptide mapping. The location of the glycoprotein identified by the monoclonal antibody was restricted to the spines of the schistosomular surface, the tubercle-associated spines of the male worm, and the dorsal spines of the female worm. The spine glycoprotein was readily purified by immunoaffinity chromatography. These findings are discussed in relation to parasite development and the relevance of this antibody for serodiagnosis and immunoprophylaxis.