Use of Clinical Samples to Identify Influenza Virus Antigenic Variants

利用临床标本鉴定流感病毒抗原变异株 摘要 甲型流感病毒(IAV)引起大流行和季节性爆发，导致数千人死亡 数百万人的生命。接种疫苗是预防流感暴发并将其降至最低限度的最佳选择 效果。了解流感病毒的抗原进化和快速选择井- 匹配的流感疫苗毒株是制定有效疫苗接种计划的关键。然而，抗原性 流感病毒的特性面临两大挑战：1)病毒繁殖，这是在 传统的血清学检测可能导致病毒的培养适应突变并扭曲其抗原性。 在临床样本中，以及2)用于常规血清学检测的参考血清是在流感中产生的 病毒血清阴性的雪貂，并不代表人类血清的免疫学特征，这通常是 通过接种疫苗、自然感染或两者兼而有之的方式接触过流感病毒。一个理想的平台 流感病毒抗原性的测定和流感疫苗株的选择应直接 使用临床样本。 该项目的目标是1)开发和应用一种新的高通量技术来直接 用不分离病毒的人类临床标本表征流感病毒的抗原性 2)直接利用临床标本了解IAV的抗原进化。这个 抗原特征将包括流感病毒阳性的临床样本，病毒可以或不能从这些样本中获得 要有教养。了解临床标本中流感病毒准种及适应培养的效果 突变的抗原特征，我们将在临床上进行下一代基因组测序 样本和相应的分离物。然后我们将研究序列多样性对抗原的影响 流感病毒的变异。我们还将确定先前接触流感病毒的影响 流感疫苗株筛选中的抗原性研究。 该项目将帮助我们为表征流感的抗原性提供基础技术。 临床样本中的病毒不会传播病毒。由此产生的抗原性鉴定平台将 克服常规血清学检测中病毒繁殖引起的偏差。此外，这是一个很高的- 并将显著减少血清学鉴定所需的人力， 减少抗原鉴定所需的时间，增加抗原性样本的数量 人物刻画。因此，该项目将导致流感疫苗毒株的重大技术进步。 选择和方便流感防控。此外，该项目还将提供有关 流感病毒准种和基因组抗原变异的分子机制 多样性和关于人类先前接触流感病毒的知识，这将帮助我们优化抗原 在疫苗株选择和了解流感病毒抗原性进化方面的特征。

Use of Clinical Samples to Identify Influenza Virus Antigenic Variants Summary Influenza A viruses (IAVs) cause pandemic and seasonal outbreaks that lead to the loss of thousands to millions of human lives. Vaccination is the best option for preventing influenza outbreaks and minimizing their effects. An understanding of the antigenic evolution of influenza viruses and the rapid selection of a well- matched influenza vaccine strain is the key to developing an effective vaccination program. However, antigenic characterization for influenza viruses presents two great challenges: 1) virus propagation, which is required in conventional serologic assays, can cause culture-adapted mutations and skew antigenic properties of viruses in clinical samples, and 2) reference sera used in conventional serologic assays are produced in influenza virus–seronegative ferrets and do not represent the immunologic profiles of human serum, which often has had prior exposures to influenza viruses through vaccination, natural infection, or both. An ideal platform for determining antigenic properties of influenza viruses and for selecting influenza vaccine strain should directly use clinical samples. The objectives of this project are 1) to develop and apply a novel high-throughput technology to directly characterize antigenic properties of influenza viruses by using human clinical samples without virus isolation and propagation and 2) to understand antigenic evolution of IAVs by using clinical samples directly. The antigenic characterization will include influenza virus–positive clinical samples from which virus can or cannot be cultivated. To understand influenza virus quasispecies in clinical samples and the effect of culture-adapted mutations on antigenic characterization, we will perform next-generation genomic sequencing on the clinical samples and corresponding isolates. We will then study the effects of the sequence diversity on antigenic variations of influenza viruses. We will also determine the effect that prior exposure to influenza virus(es) has on antigenic characterization during influenza vaccine strain selection. This project will help us provide fundamental technology for characterizing the antigenicity of influenza viruses in clinical samples without propagating virus. The resulting platform for antigenic characterization will overcome biases arising from virus propagation in conventional serologic assays. In addition, this is a high- throughput method and will significantly reduce the human labor needed for serologic characterization, decrease the time required for antigenic characterization, and increase the number of samples in antigenic characterization. Thus, this project will lead to significant technologic advances in influenza vaccine strain selection and facilitate influenza prevention and control. In addition, this project will provide knowledge about molecular mechanisms in antigenic variations associated with influenza virus quasispecies and genomic diversity and knowledge about prior human exposure to influenza viruses, which will help us optimize antigenic characterization in vaccine strain selection and understand antigenic evolution of influenza viruses.