Kleinschmidt Annett, Vadivelu Kumaran, Serino Laura, Neidig Nina, de Wergifosse Bertrand
GSK, Marburg, Germany.
GSK, Siena, Italy.
NPJ Vaccines. 2021 Feb 23;6(1):29. doi: 10.1038/s41541-021-00286-8.
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.
针对B群脑膜炎球菌（MenB）疫苗的免疫原性在上市前已通过人血清杀菌活性测定法（hSBA）进行评估，该测定法针对少量菌株进行检测。我们报告了一种替代定性hSBA的鉴定/验证情况，该方法使用接种疫苗者血清中存在的内源性补体（enc-hSBA）。在成人接种4组分MenB疫苗（4CMenB）之前和之后采集血清样本。在鉴定实验中使用了一组具有代表性的侵袭性分离株和4种抗原特异性指示菌株。每种菌株在≥3次实验中使用接种前/后血清进行检测，以评估中间精密度。一个包含110种菌株的小组和4种指示菌株符合鉴定标准，证明了测定的精密度。使用4种指示菌株证明了测定的稳健性、特异性和敏感性。Enc-hSBA具有高度标准化的特点，允许对大量与流行病学相关的MenB菌株进行检测，并考虑到接种疫苗者之间的补体活性差异。因此，enc-hSBA能够更准确地评估针对MenB疫苗的有效性。
