Immunological Reactions between Dextran Polysaccharide and Some Bacterial Antisera

Dextran, the synthetic polysaccharide produced by Leuconostoc mesenterioides from saccharose, reacts immunologically with antisera from pneumococci, some of the Sahnonella and some of the types of Streptococcus viridans (Bargen). This immunological relationship is independent of the specific antipolysaccharide antibodies of these sera, suggesting the existence of a distinct antibody produced by an active group of the specific bacterial polysaccharide, which is similar or identical to the active group of the dextran polysaccharide.