CAPSULATION OF PNEUMOCOCCUS WITH SOLUBLE C-LIKE (Cs) POLYSACCHARIDE

Abstract
Capsulated mutants of pneumococcus producing a capsule of soluble polysaccharide related immunologically to the C or cell wall polysaccharide of pneumococcus have been isolated from several noncapsulated variants of this organism. The capsular material of these strains reacts with antisera both to homologous strains and to noncapsulated strains of pneumococcus and with human C-reactive protein. C-reactive protein has been shown to give a positive capsular precipitin or Quellung reaction with Cs pneumococcal variants and to agglutinate them.