Group a Streptococcus Polysaccharide: Studies on Its Preparation, Chemical Composition, and Cellular Localization after Intravenous Injection into Mice

A method was developed for the extraction of the group A streptococcus polysaccharide employing pepsin digestion of ground streptococcal cells. This method did not result in the isolation of polysaccharide with chemical and physical chemical properties different from those exhibited by preparations extracted with hot formamide. Studies of the chemical composition of this polysaccharide demonstrated it to be composed chiefly of rhamnose and glucosamine monosaccharide units in the approximate ratio of five moles of rhamnose to two moles of glucosamine. The fate of the polysaccharide after intravenous injection into mice was studied using the fluorescent antibody technique. It was found to be rapidly eliminated by the kidney. The presence of the polysaccharide in the renal tubular epithelial cells during the excretory phase was the only evidence of its cellular localization that could be detected under the conditions of these experiments.