HOST-PARASITE FACTORS IN GROUP A STREPTOCOCCAL INFECTIONS* A CO~ARATIVE STImY OF STREPTOCOCCAL PYROGENIC TOXINS AI~rD GRA~- NEGATIVE BACTERIAL ENDOTOXIN BY NATALIE

There are few reports in the literature (1--4) on the pyrogenicity of streptococci or streptococcal filtrates. The most recent detailed investigations on streptococcal pyrogenic activity were reported by Stetson (5) and Watson (6). Stetson reported on the endotoxic activity of Group A streptococci grown in vitro. On the basis of studies with lysates of streptococci disrupted in a Mickle disintegrator, he suggested that streptococci possess an endotoxin similar to that of Gram-negative bacteria. Watson worked with extracellular products of Group A streptococci grown in vivo. Sterile extracts, prepared from rabbit lesions produced by intradermal injection of various types of Group A streptococci, contained pyrogenic toxins which were immunologically distinct. These toxins had other manifestations, causing lethality, cardiotoxic and other tissue damage, and enhancement of toxicity. They were identiffed with the scarlet fever group of toxins.