Immunochemical Studies on the Specific Polysaccharide of Type II Pneumococcus

Abstract

Preparations of type II pneumococcal capsular polysaccharides have been studied with respect to their reactivity with homologous type II antiserum and their cross reaction with rabbit anti-Friedlander B. From their capacities to precipitate antibody, from methylpentose analyses on specific precipitates formed with excess antibody, and from supernatant tests, it was concluded that certain of these preparations had undergone degradation. A sample of SII was obtained which showed no evidence of degradation by any of the immunochemical criteria employed. The findings are discussed in relation to the value of immunochemical methods in defining criteria of purity of high molecular weight substances.