POSSIBLE ROLE FOR A POLYSACCHARIDE ANTIGEN SHARED BETWEEN STREPTOCOCCUS-PYOGENES AND STREPTOCOCCUS-MUTANS IN THE PATHOGENESIS OF POSTSTREPTOCOCCAL GLOMERULONEPHRITIS

Streptcoccus mutans has been shown to share a polysaccharide (PS) anti gen with S. pyogenes strains isolated from patients with acute poststr eptococcal glomerulonephritis (PSGN), using a monoclonal antibody f-77 reactive with the PS.(1) To investigate the pathogenetic role of the shared PS in PSNG, experimental nephritis was induced, in animals. Rat s were immunized thrice with heat-killed cells of S. mutans or S. pyog enes, followed by an intravenous injection of live cells of S. pyogene s. Histologic examination showed that both animal groups had comparabl e degrees of diffuse proliferative nephritis characterized by immune d eposits. The shared PS antigen was detected in glomeruli of all nephri tic rats by immunofluorescence using monoclonal antibody f-77. Further more, all nephritic rats had an elevated antibody titer To the shared PS antigen. These results suggest that prior sensitization (infections such as dental caries) to S. mutans modulates immune responses to sub sequent S. pyogenes infections and induces immune-complex disease (PSG N) through the shared PS antigen.