Soluble blood group reactive substances in the hemolymph of Biomphalaria glabrata (Mollusca)

The hemagglutinating activity of Biomphalaria glabrata hemolymph was examined with different erythrocyte samples of several human donors. The agglutinin was not specific for the ABO blood group antigens of man. In further tests, the hemolymph was investigated for soluble inhibitors of anti-human blood group agglutinins. An inhibition was observed with respect to human anti-A and anti-B isoagglutinins as well as to anti-P and anti-H reagents. These results were confirmed in agar-gel double diffusion tests: The hemolymph showed very strong precipitation lines with several anti-A, anti-B, and anti-H lectins of invertebrate and plant origins. Some of the indicated blood group reactive substances were identified as glycoproteins. The role of these sugar-containing macromolecules in the relationship between Schistosoma miracidia and the intermediate host snail Biomphalaria glabrata is discussed.