Immunochemical studies on cross-reactions of antipneumococcal sera. I. Cross-reactions of types II and XX antipneumococcal sera with dextrans and of type II antipneumococcal serum with glycogen and Friedlaender type B polysaccharide.

The cross-reaction of anti-SII with Friedlander Type B polysaccharide seems to involve a fraction of anti-SII independent, at least in part, from the fraction cross-reacting with dextrans. Quantitative inhibition studies with oligosaccharides showed that glucuronic acid residues may be involved in this cross-reaction since glucuronic acid was the only inhibitor tested which was effective.