A Study of the Antibodies to Group A Streptococcal T Antigen in Human Serum

Abstract

T antigen of group A streptococcus has been thought as one of the common antigens to some of the different M types. However, T-typing method is practically more useful than M-typing for the identification of group A streptococci due to the stability in its antigenicity.
In this paper, the method of testing of agglutinins in rabbit and the application of this method tohuman sera were examined with the following results.
1) With the same procedure as the preparation of T monovalent serum from rabbit hyperimmuneserum, it was shown that the specific antibody to T protein existed in human serum.
2) It was confirmed that the T antibody was predominantly positive to the T type isolated from the patient about 5 weeks after the onset of pharyngitis.
3) In the sera from carriers, the positive rate and the endtiter of agglutinins to the standard T antigens were higher to the T types isolated from carriers than the other types.
4) T agglutinin of the healthy carriers was examined against the prevalent types in Japan including type 1, 4, 6, 12, and so on. Positive rate of T agglutinins to any one of the tested antigens was 68.5% in the primary school children and 44.0% in adults.
5) There observed that the T antibody pattern was different according to the groups, age, sex, and place.