THE PURIFICATION, CHARACTERIZATION, SEROLOGICAL ACTIVITY AND HEPATOTOXIC PROPERTIES OF 2 CATIONIC GLYCOPROTEINS (ALPHA-1 AND OMEGA-1) FROM SCHISTOSOMA-MANSONI EGGS

T cell-deprived mice acutely infected with S. mansoni suffer microvesicular hepatocyte damage which is not seen in infected, immunological intact animals. A cationic fraction (CEF6) of the PBS-soluble portion of S. mansoni eggs (SEA) induces antibodies which, on passive transfer, prevent hepatocyte damage. CEF6 contains 2 antigens, omega-1 and alpha-1, and has also been shown to be a useful serodiagnostic reagent. This paper describes the purification and characterization of the 2 antigens present in CEF6. omega-1 is a monomeric glycoprotein with a pI > 9.0 and a molecular weight of 31 kDa. alpha-1 consists of two immunologically cross-reactive dimers, 41 and 36 kDa in non-reducing conditions, each of which consists of one unique and one common glycoprotein subcomponent. In ELISA with mouse and human infection sera omega-1 is shown to be S. mansoni specific and is better able to distinguish S. mansoni infections from other schistosome infections than are unfractionated SEA, CEF6 or alpha-1. Passive transfer of monospecific anti-omega-1 sera into S. mansoni infected, T cell-deprived mice completely prevented the occurrence of microvesicular hepatocyte damage in these animals. Monospecific anti-alpha-1 serum had no hepatoprotective capacity.