Immunofluorescent and immunoelectron microscopic demonstration of primate heart muscle antigens cross-reactive with Streptococcus pyogenes.

The presence of antigens in heart muscles cross-reactive with antibodies against Streptococcus pyogenes were examined in heart samples of seven primate species (chimpanzee, rhesus macaque, stump-tailed macaque, hamadryas baboon, capuchin monkey, green monkey and patas monkey). Cross-reactive antigens were localized by means of the indirect immunofluorescent technique in nearly all samples tested. The fluorescence pattern was the same as found in the heart muscle of other mammals. Using the indirect immunoferritin technique the substructural distribution of the antigens was investigated in heart muscle of rhesus macaque and hamadryas baboon. Beside the location on the cell surface the antigens were also demonstrated within the cell. Above all there was a strong labelling along the intercalated discs and in the sarcoplasmatic reticulum.