<i>Schistosoma bovis</i> as an immunological analogue of <i>S. haematobium</i>

<jats:p><jats:bold>Summary</jats:bold> The host‐parasite relationships of <jats:italic>Schistosoma bovis</jats:italic> and <jats:italic>S. haematobium</jats:italic> have been compared in normal and T‐cell‐deprived mice, and have been found to contrast with that of S. <jats:italic>mansoni.</jats:italic> Deprived mice infected with either of the former two schistosome species survived as long as, or longer than, comparably infected immunologically intact controls, and hepatocytes of infected deprived mice were not damaged in the absence of granuloma formation. <jats:italic>S.</jats:italic> ma/wow'‐infected deprived mice, however, die earlier than intact controls, and surfer extensive hepatocellular abnormalities. A high degree of cross‐reactivity between <jats:italic>S. bovis, S. haematobium</jats:italic> and <jats:italic>S. mansoni</jats:italic> antibodies and antigens was noted in immunoprecipitation but a greater degree of homology between <jats:italic>S. haematobium</jats:italic> and <jats:italic>S. bovis</jats:italic> egg antigens was demonstrated by enzyme immunoassay (ELISA). <jats:italic>S. haematobium</jats:italic> and <jats:italic>S. bovis</jats:italic> thus resemble each other more closely than either resembles <jats:italic>S. mansoni</jats:italic>, and in view of the apparent antigenic similarities between <jats:italic>S. haematobium</jats:italic> and <jats:italic>S. bovis</jats:italic> and the relatively greater ease with which the <jats:italic>S. bovis</jats:italic> life‐cycle can be maintained in the laboratory, the animal parasite may be useful in providing material for further immunological studies of the human infection.</jats:p>