Is the nephritogenic antigen in post-streptococcal glomerulonephritis pyrogenic exotoxin B (SPE B) or GAPDH?
GROUND: Acute glomerulonephritis can follow infection by group A streptococci. An immune-complex pathogenesis is accepted, but the causative antigen(s) is still controversial. In recent years, 2 streptococcal antigens, the cationic cysteine proteinase exotoxin B (SPE B) and the plasmin receptor, a glyceraldehyde phosphate dehydrogenase (Plr, GAPDH) have attracted attention because: (1) they were localized in glomeruli in patients with acute post-streptococcal glomerulonephritis (APSGN); and (2) serum antibody to these antigens was associated with nephritogenic streptococcal infections. To date, putative nephritogens were always tested independently. Here, the relevance of SPE B and GAPDH was evaluated in the same renal biopsies and serum samples of well-defined APSGN patients. METHODS: Renal biopsies (17 patients) and serum samples (53 patients) with APSGN and appropriate controls were examined. Immunofluorescent staining of frozen sections was performed using specific antibodies to SP
