Studies on the O Antigen of Salmonella typhosa IV. Endotoxic Properties of the Purified Antigen

Publisher Website
Google Scholar
Abstract
A study was made of the endotoxic properties of a protein-free lipopolysaccharide isolated from the 0-901 strain of S. typhosa. The product was lethal for rabbits in a dose range of 20-30 [mu]g while 300-500 [mu]g were required to kill mice. The minimum pyrogenic dose in rabbits was 0.0002 [mu]g, characterizing it as a pyrogen of extremely high potency. In a quantitative study of the local Shwartzman reaction, 1 [mu]g or less was effective as a preparatory or provocative dose. Its activity in eliciting bilateral renal cortical necrosis, the lesion characteristic of the generalized Shwartzman reaction, was in the range of 5-20 [mu]g. Thus, very small quantities of a lipopolysaccharide, freed of protein, are capable of producing the various biological alterations generally attributed to endotoxins.