title: Comparison of an opsonophagocytic assay and IgG ELISA to assess responses to pneumococcal polysaccharide and pneumococcal conjugate vaccines in children and young adults with sickle cell disease.
abstract: Children with sickle cell disease were immunized with either 2 doses of 7-valent pneumococcal conjugate vaccine followed by 1 dose of 23-valent pneumococcal polysaccharide vaccine or a single dose of 23-valent vaccine. Functional antibodies to 7 vaccine serotypes were measured by a flow cytometric opsonophagocytic assay (OPA) and compared with IgG anticapsular polysaccharide antibody concentrations measured by ELISA. Moderate correlations were found between OPA and ELISA antibody titers for all 7 serotypes (r values, 0.41-0.70; P<.001 for all serotypes). After immunization with 23-valent vaccine, geometric mean antibody titers by OPA were significantly higher in the combined schedule group for 5 of 7 vaccine serotypes but were significantly higher for only 2 of 7 serotypes as measured by ELISA. The ability of OPA to show a greater differential response to the 2 immunization schedules used in this study suggests that it may be useful in the evaluation of immunization regimens involving pneumococcal conjugate vaccines.
authors.affiliation: Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.
authors.forename: L
authors.initials: L
authors.lastname: Vernacchio
authors.forename: S
authors.initials: S
authors.lastname: Romero-Steiner
authors.forename: J E
authors.initials: JE
authors.lastname: Martinez
authors.forename: K
authors.initials: K
authors.lastname: MacDonald
authors.forename: S
authors.initials: S
authors.lastname: Barnard
authors.forename: T
authors.initials: T
authors.lastname: Pilishvili
authors.forename: G M
authors.initials: GM
authors.lastname: Carlone
authors.forename: D M
authors.initials: DM
authors.lastname: Ambrosino
authors.forename: D C
authors.initials: DC
authors.lastname: Molrine
mesh_terms: D000293:Adolescent; D000755:Anemia, Sickle Cell / Q000276:immunology*; D000907:Antibodies, Bacterial / Q000097:blood*; D001428:Bacterial Vaccines / Q000276:immunology*; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007114:Immunization; D007074:Immunoglobulin G / Q000097:blood*; D010587:Phagocytosis; D022242:Pneumococcal Vaccines; D013296:Streptococcus pneumoniae / Q000276:immunology*; D018074:Vaccines, Conjugate / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate