Relationship between haptoglobin and Streptococcus pyogenes T4 antigens

Abstract

DURING a survey of agglutinating activity of human saliva against streptococci¹ we found that saliva from individuals of blood group 0 agglutinated a particular strain of group G streptococci more often than did serum from those with blood group A or B. When we tested 833 sera we found a dimorphism for antibody-like substances against group G streptococci—sera could be divided into two groups according to their agglutination titre against group G streptococci. The first group had low titres, not rising above 1 : 4 and more usually 1 : 1; the second group had much higher titres ranging from 1 : 200 to 1 : 3,200. There was no overlap between the two groups of sera. We thought that this might be related to a genetic system, probably diallelic. We now report a relationship between the haptoglobin genotype of serum and the streptococcal antigens with which it reacts.