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

Abstract

Cameron and Staveley¹ 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-P₁ sera are produced in goats². In rabbits the production of P₁ antibodies can also be stimulated, but not by application of the cyst fluid alone³. We have explored another source of antigen, Lumbricus terrestris⁴. Sodium chloride extracts, both cooked and uncooked, contain a fairly large amount of P₁ 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 P₁ cold antibodies which are ‘genuinely’ present in the sera of P₂ 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-P₁ sera as well as A and H substances. By means of sodium chloride extracts from Lumbricus, P₂ erythrocytes pretreated with tannin can be transformed into P₁ 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.