Analytical Research & Development, MRL, Merck & Co., Inc., Kenilworth, NJ, USA.
Analytical Research & Development, MRL, Merck & Co., Inc., Kenilworth, NJ, USA.
J Immunol Methods. 2021 Jul;494:113054. doi: 10.1016/j.jim.2021.113054. Epub 2021 Apr 15.
Respiratory syncytial virus (RSV) is a common pathogen causing severe respiratory illness in infants and elder adults. The development of an effective RSV vaccine is an important unmet medical need and an area of active research. The traditional method for testing neutralizing antibodies against RSV in clinical trials is the plaque reduction neutralization test (PRNT), which uses 24-well plates and needs several days post infection to develop viral plaques. In this study, we have developed a virus reduction neutralization test (VRNT), which allows the number of RSV infected cells to be automatically counted by an imaging cytometer at one day post infection in 96-well plates. VRNT was found robust to cell seeding density, detection antibody concentration, virus input and infection time. By testing twenty human sera, we have shown good correlation between VRNT50 and PRNT50 titers for multiple RSV strains: A2, Long and 18537 (serotype B). To understand the VRNT performance, eight human serum samples with high, medium and low neutralization titers were selected for VRNT qualification. We have demonstrated that VRNT had good specificity, precision, linearity and relative accuracy. In conclusion, VRNT is a better alternative to PRNT in serum neutralization test for RSV vaccine candidates.
呼吸道合胞病毒（RSV）是一种常见的病原体，可导致婴儿和老年人严重的呼吸道疾病。开发有效的 RSV 疫苗是一个重要的未满足的医学需求，也是一个活跃的研究领域。临床试验中检测针对 RSV 的中和抗体的传统方法是蚀斑减少中和试验（PRNT），该方法使用 24 孔板，并且需要在感染后几天才能形成病毒蚀斑。在这项研究中，我们开发了一种病毒减少中和试验（VRNT），该试验允许在感染后一天通过成像细胞仪在 96 孔板中自动计数 RSV 感染的细胞数。VRNT 对细胞接种密度、检测抗体浓度、病毒输入和感染时间具有稳健性。通过测试 20 个人血清，我们已经证明了 VRNT50 与多种 RSV 株（A2、Long 和 18537（血清型 B）的 PRNT50 滴度之间具有良好的相关性。为了了解 VRNT 的性能，我们选择了 8 个人血清样本，这些样本具有高、中和低中和滴度，用于 VRNT 资格鉴定。我们已经证明 VRNT 具有良好的特异性、精密度、线性和相对准确性。总之，VRNT 是 RSV 疫苗候选物血清中和试验中比 PRNT 更好的替代方法。
