Abstract
The toxic cellular component of Group A streptococci, which produces a chronic multinodular lesion of the dermal connective tissue of rabbits, has been isolated by means of differential centrifugation and electrophoresis. The substance appeared to be a macromolecular complex of polysaccharide and protein, the polysaccharide having the serological and chemical characteristics of the group-specific C substance. Evidence is presented indicating that the polysaccharide moiety is an essential part of the toxic complex. It is suggested that further studies of this material may help elucidate the mechanism of tissue damage in the non-suppurative sequelae of Group A streptococcal infections.