Human antibody responses to capsular polysaccharides of Streptococcus pneumoniae 6B, 14, and 19F

Human antibody responses to Streptococcus pneumoniae 6B, 14, and 19F capsular polysaccharide were analyzed. Thirty-one healthy young adults were immunized with the pneumococcal 23-valent PS vaccine. Serum samples were obtained from them before and 1 month after vaccination. The amounts of total antibody, heavy chain and light chain isotypes were determined by enzyme-linked immunosorbent assay (ELISA). Vaccination increased the total levels of anti-6B, anti-14, and anti-19F PS antibodies by 3.4-fold, 3.8-fold and 4.1-fold, respectively. Some individuals showed great variations in antibody responses to different serotypes of PS. The IgG antibody was predominant in the responses to the three PSs, and most of the IgG anti-PS antibodies were IgG2 isotype. There was no significant difference in the κ and γ. responses.