PDF(Pubmed)
Abstract：
Six serotypes (Ia, Ib, II, III, IV, and V) cause nearly all group B streptococcal (GBS) disease globally. Capsular polysaccharide (CPS) conjugate vaccines aim to prevent GBS disease, however, licensure of a vaccine would depend on a standardized serological assay for measuring anti-CPS IgG responses. A multiplex direct Luminex-based immunoassay (dLIA) has been developed to simultaneously measure the concentration of serum IgG specific for the six prevalent GBS CPS serotypes. Assay validation was performed using serum samples obtained from human subjects vaccinated with an investigational 6-valent GBS CPS conjugate vaccine. Results for the assay are expressed as IgG concentrations (µg/mL) using a human serum reference standard composed of pooled sera from vaccinated subjects. The lower limits of quantitation (LLOQ) for all serotypes covered in the 6-plex GBS IgG dLIA fell within the range of 0.002-0.022 µg/mL IgG. Taken together, the 6-plex GBS IgG dLIA platform is specific for the six GBS serotypes included in Pfizer\'s investigational vaccine, has a wide dilution adjusted assay range, and is precise (<18.5% relative standard deviation) for all serotypes, and, therefore, is suitable for quantitatively measuring vaccine-induced or naturally acquired serotype-specific anti-CPS IgG responses against GBS.
摘要：
六种血清型（Ia，Ib,II,III,IV,和V）引起全球几乎所有B组链球菌（GBS）疾病。荚膜多糖（CPS）结合疫苗旨在预防GBS疾病，然而,疫苗的许可将取决于用于测量抗CPSIgG应答的标准化血清学测定。已开发出基于Luminex的多重直接免疫测定法（dLIA），以同时测量对六种流行的GBSCPS血清型具有特异性的血清IgG浓度。使用从用研究性6价GBSCPS缀合物疫苗接种的人受试者获得的血清样品进行测定验证。使用由来自接种受试者的合并血清组成的人血清参考标准,将测定结果表示为IgG浓度(yg/mL)。6-plexGBSIgGdLIA中涵盖的所有血清型的定量下限（LLOQ）在0.002-0.022µg/mLIgG的范围内。一起来看,6-plexGBSIgGdLIA平台对辉瑞研究性疫苗中包含的六种GBS血清型具有特异性，具有广泛的稀释调整测定范围，并且对所有血清型都是精确的（<18.5%的相对标准偏差），and,因此,适于定量测量针对GBS的疫苗诱导的或天然获得的血清型特异性抗CPSIgG应答。
