Relation Between Skin Reactions to Specific Carbohydrate Type I Pneumococcus and Human Blood Groups

Abstract

Tillett and Francis 1 demonstrated the occurrence of a wheal and erythema reaction to the intradermal injection of minute amounts of the homologous type-specific pneumococcus polysaccharide in patients recovering from pneumococcus pneumonia. Subsequent studies by a number of investigators 2 have, in general, confirmed their findings. These authors showed, furthermore, that positive skin tests of this sort were not restricted to cases immediately or even remotely convalescent from pneumonia, but that an appreciable number of supposedly perfectly healthy individuals also gave positive skin tests. Using the Type I carbohydrate the percentage of positive reactions in normal persons was variously reported from 11.6% to 71%. In our own experience prior to the present series positive tests had been encountered in about 70% of normal cases. 3

Recently Witebsky, Neter, and Sobotka 4 have shown the existence of a close immunological relationship between the Type I Pneumococcus acetyl polysaccharide of Avery and Goebel 5 and the human blood group specific substance A. These authors pointed out, among other observations, that the iso-agglutination of human blood group A corpuscles could be inhibited by Type I Pneumococcus acetyl polysaccharide. They presented strong evidence by means of this method, and also by employing complement fixation and hemolysis inhibition tests, that the relationship was specifically associated with the acetyl polysaccharide and that it was lost in the deacetylated polysaccharide.

These observations upon the relationship between the blood group specific substance A and the Type I Pneumococcus acetyl polysaccharide led to the present attempt to establish a correlation between human blood groups and positive skin tests to the Type I acetyl polysaccharide in so-called normal, non-convalescent persons.