STUDIES ON THE IMMUNE RESPONSE OF THE RHEUMATIC SUBJECT AND ITS RELATIONSHIP TO ACTIVITY OF THE RHEUMATIC PROCESS. IV. CHARACTERISTICS OF STRAINS OF HEMOLYTIC STREPTOCOCCUS, EFFECTIVE AND NON-EFFECTIVE IN INITIATING RHEUMATIC ACTIVITY 1

Abstract

IV. Of 40 strains of hemolytic streptococcus associated with pharyngeal infection in rheumatic subjects one halt were effective in initiating intense rheumatic activity, the other half were not. All strains were of the human type, culturally alike, and predominantly Strep. pyogenes. However, while effective drains produced strong skin toxins and streptolysins, and gave rise to production of high antistreptolysin titres in subjects from whom they were isolated, ineffective strains were characterized by absence of these properties.[long dash]V. In view of the apparent close relationship between infection with skin toxin producing hemolytic streptococci and initiation of rheumatic activity in susceptible subjects, expts. were made to determine the effect of increased circulating antitoxin, actively or passively produced. Practically all of 100 healthy nurses immunized with toxin became Dick negative. Respiratory infection associated with streptococci was not, however, prevented nor were rheumatic sequelae, in such instances, inhibited. Ten subjects in whom the rheumatic process was quiescent at the time, but with acute pharyngitis associated with the presence of hemolytic streptococci in the throat, were used in the passive immunization expts. Anti-streptococcus serum (N.Y.5) failed to prevent rheumatic recrudescences in 6 of 7 persons in whose throats toxin producing strains were found. Authors suggest that, if the toxin plays a role in the genesis of rheumatic lesions, the relationship is not a simple one of direct damage to mesodermal tissues, but that its effectiveness depends on the immune response of the host.[long dash]VI. There is a sharp rise in antistreptolysin titer with onset of a rheumatic attack, the median of the values developed being 500 units. Those patients who became infected with hemolytic streptococcus but did not suffer a recrudescence developed no antistreptolysin. The high values fell to natural levels in approximately a year, the rate of fall varying markedly in different subjects.[long dash]VII. Rheumatic attacks developing within 6 months following splenec-tomy (20 children) seemed less severe than usual. After 1 yr., however, all attacks were typical of acute rheumatism. The immune response (rise in antistreptolysin titer with an attack) was not permanently modified.