Schistosoma mansoni: A comparison of mouse and rat worms with respect to host antigens detected by the technique of transfer into hamsters

A significant proportion of schistosomes transferred from the mouse into the mesenteric veins of hamsters pre-immunized with mouse erythrocytes were rejected. The rejection was specific, could be passively transferred with immune serum and was demonstrable with mouse worms which had been ‘washed’ in normal hamsters for up to 24 h. On the contrary, schistosomes transferred from the rat into the mesenteric veins of hamsters pre-immunized with rat erythrocytes were generally not rejected to any significant extent. Rejection was not brought about by variations in the immunization procedure, or by passive transfer of immunity, or by the use of ‘older’ rat worms. Rat antigens could be detected on rat schistosomes with the use of mixed agglutination techniques, but they appeared to be present in relatively low amounts. The significance of these findings is discussed in relation to a possible protective function of host antigens.