[Secretory antibodies in saliva against group G streptococci (author's transl)].

Saliva of 310 persons were examined for their ability to agglutinate 33 streptococcal strains of the groups A-T. It was found that the saliva of persons with blood group O agglutinated significantly more often streptococci of strain G9 than the saliva of persons with blood group A (33.3%, and 18.75% resp., p less than 0.01). A statistical significant difference between persons of blood group B and O, or A and B did not exist. The agglutination reactions were caused probably by unspecific immunoglobulins because this strain G9 binds unspecifically human IgG. It is known, that some streptococcal strains of the groups A, B, C, D, and G contain receptors for the Fc-fragment of IgG and/or IgA. The results demonstrate that persons of the blood group O secrete more often immunoglobulin than those with blood group A.