P1 Blood Group Substance in Lumbricus terrestris (Earthworm) and Ascaris suum

Cameron and Staveley 1 found that the echinococcus cyst fluid contains P blood group substance if there are scolices present in the cysts. When the echinococcus cyst fluid is used as an antigen, excellent anti- P 1 sera are produced in goats 2 . In rabbits the production of P 1 antibodies can also be stimulated, but not by application of the cyst fluid alone 3 . We have explored another source of antigen, Lumbricus terrestris 4 . Sodium chloride extracts, both cooked and uncooked, contain a fairly large amount of P 1 substance together with H substance and B blood group substance. Some of the extracts inhibited also anti- A , but never anti- M , anti- N , or anti- D . The long-lasting immunity of man against Ascaris gave rise to the idea that the P 1 cold antibodies which are ‘genuinely’ present in the sera of P 2 group people could have developed following antigenic stimulation by Ascaris lumbricoides or other nemathelminthes. We therefore studied sodium chloride extracts from Ascaris suum and observed a high content of substance inhibiting anti- P 1 sera as well as A and H substances. By means of sodium chloride extracts from Lumbricus , P 2 erythrocytes pretreated with tannin can be transformed into P 1 erythrocytes. The extract can be cooked and we have been using it for the immunization of goats. The detailed quantitative relations will be referred to elsewhere.