Total and serotype-specific pneumococcal antibody titres in children with normal and abnormal humoral immunity

• Published in: Vaccine 2006-07, Vol.24 (27), p.5637-5644
• Main Authors: Uddin, Sharif, Borrow, Ray, Haeney, Mansel R., Moran, Andrew, Warrington, Rosalind, Balmer, Paul, Arkwright, Peter D.
• Format: Article
• Language: English
• Subjects: Adolescent; Age; Age Factors; Antibiotics; Antibodies, Bacterial - blood; Antibodies, Bacterial - immunology; Antibody Formation - immunology; Antibody Specificity; Antigens; Applied microbiology; Bacterial diseases; Bacteriology; Biological and medical sciences; Child; Child, Preschool; Children; Cloning; Cohort Studies; Disease; DNA repair; Female; Fundamental and applied biological sciences. Psychology; Heptavalent Pneumococcal Conjugate Vaccine; Humans; Immunoglobulin G - immunology; Male; Meningococcal Vaccines - immunology; Meningococcal Vaccines - therapeutic use; Microbiology; Miscellaneous; Mortality; Pneumococcal antibodies; Pneumococcal Vaccines - immunology; Pneumococcal Vaccines - therapeutic use; Pneumonia; Polysaccharides, Bacterial - immunology; Serotypes; Streptococcus infections; Streptococcus pneumoniae; Streptococcus pneumoniae - immunology; Tetanus; Vaccine; Vaccines; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects)
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2006.03.088

A heptavalent pneumococcal conjugate vaccine (PCV-7) protects children against invasive pneumococcal disease. The aim of this study was to evaluate immunoglobulin subclass and serotype-specific pneumococcal antibody responses to vaccination in children with a history of recurrent or severe bacterial infections. Pneumococcal IgG, IgG1, IgG2 titres were assayed by ELISA, and nine serotype concentrations measured using a nonaplex bead assay in 145 children investigated for recurrent or severe infections. Children mounted an exclusively IgG1 response after vaccination with two doses of PCV-7 and a dose of 23 valent pneumococcal polysaccharide vaccine (PPV-23), with pneumococcal IgG2 antibody titres remaining low to negligible. Measurement of serotype-specific responses demonstrated that although PCV-7 specific serotype responses increased significantly post-vaccination, specific IgG against two of the serotypes not covered by PCV-7 but only by PPV-23 remained low. We conclude that in contrast to antibody response to natural infection with Pneumococcus or pneumococcal polysaccharide vaccines which are often of a IgG2 subclass, responses in children after PCV-7 are of IgG1 subclass. Serotype-specific IgG were useful in determining the protection against specific pneumococcal strains, and showed that the PPV-23 did not broaden protection against non-PCV-7 serotypes.