Endogenous complement human serum bactericidal assay (enc-hSBA) for vaccine effectiveness assessments against meningococcal serogroup B.

ABSTRACT: Immunogenicity of vaccines against meningococcal serogroup B (MenB) has been assessed pre-licensure with a human serum bactericidal activity assay (hSBA), tested against small numbers of strains. We report the qualification/validation of an alternative qualitative hSBA which uses endogenous complement (enc-hSBA) present in the vaccinee's serum. Serum samples were collected from adults pre-vaccination and post-vaccination with the 4-component MenB vaccine (4CMenB). A representative panel of invasive isolates and 4 antigen-specific indicator strains were used in qualification experiments. Each strain was tested in ?3 experiments with pre/post-vaccination sera to evaluate intermediate precision. A 110-strain panel and the 4 indicator strains met qualification criteria, demonstrating assay precision. Assay robustness, specificity and sensitivity were demonstrated using the 4 indicator strains. Enc-hSBA is highly standardized, allows testing across large panels of epidemiologically-relevant MenB strains, and accounts for complement activity differences between vaccinees. Therefore, enc-hSBA enables a more accurate estimation of effectiveness for vaccines against MenB.

SUBMITTER: Kleinschmidt A 

PROVIDER: S-EPMC7902841 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature