THE ISOLATION OF A 22 KDA BAND AFTER SDS-PAGE OF SCHISTOSOMA-MANSONI ADULT WORMS AND ITS USE TO DEMONSTRATE THAT IGE RESPONSES AGAINST THE ANTIGEN(S) IT CONTAINS ARE ASSOCIATED WITH HUMAN RESISTANCE TO REINFECTION

In schistosomiasis endemic areas, intensities of reinfection after tre atment are greater amongst young children than amongst adults, and hig h levels of parasite-specific IgE are associated with resistance to re infection in an age-dependent manner Previously we have reported that, in Western blots, a 22 kDa band was recognized by human IgE and that the incidence and intensity of S. mansoni reinfection were significant ly lower amongst individuals who had IgE against this band, compared w ith those who did not (Dunne et al, 1992). Here we report the isolatio n of a 22 kDa SDS-PAGE band, its incorporation into ELISA and the demo nstration that levels of human anti-22 kDa IgE had a significant negat ive correlation with intensities of subsequent reinfection. Rabbit ant i-22 kDa band serum recognized the outer tegument, gut tegument, and t he collecting ducts and flame cells of adult worms, The 22 kDa band an tigen(s) was also present in 'lung'- and 'post-lung' schistosomula sta ges of S., mansoni, and in S, haematobium, S. bovis and S. japonicum a dult worms. Metabolic labelling of schistosomula and worms demonstrate d the in vitro synthesis and release of 22 kDa antigens.