Binding studies with antibodies having phosphorylcholine specificity and fragments derived from their homologous Streptococcus pneumoniae type 27 capsular polysaccharide.

The capsular polysaccharide from Streptococcus pneumoniae type 27 (S-27) has been fragmented into oligosaccharides by controlled degradations. Binding of these derived small ligands with heterogeneous rabbit anti-S-27 antibody of selected phosphorylcholine affinity indicates that a major immunodeterminant of S-27 is the phosphorylcholine moiety, but that these anti-PC. antibodies are also capable of binding to the polysaccharide backbone from which the P.C. has been removed.