‘Host’ antigens associated with schistosomes: observations on their attachment and their nature

Abstract

Further investigations have been carried out on the nature of ‘host’ antigens associated with the adult worms of Schistosoma mansoni. These investigations show:1. The ‘host’ antigens are not removed from the surface of the worms by thorough washing and prolonged incubation in Hanks's balanced salts solution. The antigens must be firmly bound or even incorporated at the surface.2. Monkeys cannot be immunized against ‘mouse worms’ with mouse IgG immunoglobulins. Accordingly it is unlikely that the ‘host’ antigens are mouse anti-worm antibodies.3. The ‘host’ antigens are certainly associated with the membranes of mouse erythrocytes. They may also be associated with the ‘soluble protein’ fraction of the erythrocytes.4. Immunization with sheep erythrocytes failed to protect monkeys against challenge with ‘mouse’ worms. Therefore it is unlikely that the ‘host’ antigens are Forssman antigen.5. The mouse ‘host’ antigens associated with ‘mouse’ worms are not major histocompatibility antigens. Consequently it is likely that they are species-specific mouse antigens.