Antigenic communities were studied with sera from rabbits immunized with the Yamanashi and Chinese strains of Schistosoma japonicum eggs, and the antigens of five subspecies of Oncomelania snails, by immunoelectrophoresis.
With regard to antigenic communities defined by the Yamanashi strain of S. japonicum eggs and Oncomelania snails, the schistosome egg produced 5 to 6 bands with Oncomelania hupensis nosophora, 3 to 4 bands with O.h.hupensis, 3 bands with O.h.chiui, 2 bands with O.h.quadrasi and 1 band with O.h.formosana. Similarly, the antigenic communities defiend by the Chinese strain of S.japonicum eggs and Oncomelania snails, the schistosome egg produced 5 bands with O.h.hupensis, 4 bands with O.h.nosophora, 2 bands with O.h.chiui, 1 band with O.h.quadrasi and 0 or 1 band with O.h.formosana. Our results showed that more bands were seen between the S.japonicum egg and suitable intermediate hosts, the same as when S.japonicum adult worm antigens were used.
Antigens in common between the fractionated Oncomelania and both strains of S.japonicum eggs were found mainly in Fractions 1 and 2, and were estimated to have molecular weights of 17,000-670,000.