title: Prediction of pneumococcal conjugate vaccine effectiveness against invasive pneumococcal disease using opsonophagocytic activity and antibody concentrations determined by enzyme-linked immunosorbent assay with 22F adsorption.
abstract: We compared the abilities of two serological readouts, antipolysaccharide IgG antibody concentrations and opsonophagocytic activity (OPA) titers, to predict the clinical effectiveness of the 7-valent pneumococcal conjugate vaccine (7vCRM) against invasive pneumococcal disease (IPD). We also assessed the accuracy of the previously established thresholds for GlaxoSmithKline's enzyme-linked immunosorbent assay with 22F adsorption (22F-ELISA) (≥0.2 μg/ml) and OPA assay (titer, ≥8) in predicting effectiveness. We showed that following a 3-dose 7vCRM primary vaccination, the serological response rates as determined using thresholds of ≥0.2 μg/ml IgG and an OPA titer of ≥8 corresponded well with overall effectiveness against IPD. In addition, the OPA assay seemed to better predict serotype-specific effectiveness than enzyme-linked immunoassay. Finally, when applied to post-dose-2 immune responses, both thresholds also corresponded well with the overall IPD effectiveness following a 2-dose 7vCRM primary vaccination. These results support the importance of the OPA assay in evaluating immune responses to pneumococcal conjugate vaccines.
authors: GlaxoSmithKline Biologicals, Avenue Fleming 20 (W23), 1300 Wavre, Belgium. lode.schuerman@gskbio.com
authors: L
authors: L
authors: Schuerman
authors: J
authors: J
authors: Wysocki
authors: J C
authors: JC
authors: Tejedor
authors: M
authors: M
authors: Knuf
authors: K-H
authors: KH
authors: Kim
authors: J
authors: J
authors: Poolman
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D009895:Opsonin Proteins / Q000097:blood*; D010587:Phagocytosis; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D007074:Immunoglobulin G; D009895:Opsonin Proteins; D022242:Pneumococcal Vaccines