Early Drivers of Humoral Immunity to SARS-CoV-2 Infections

对SARS-CoV-2(CoV2)感染的体液免疫持续时间和性质尚不清楚。多数 研究的重点是临床疾病患者的免疫反应，但对抗体知之甚少。 对CoV2的反应，关于暴露后和发病前最早的免疫事件 疾病或无症状个体，以及这如何影响长期免疫记忆。这项建议 通过前瞻性地跟踪与临床病例的家庭接触来解决我们知识中的这些差距 CoV2来确定与28天的早期病毒暴露相关的先天和获得性免疫事件 句号。对这些患者的样本进行了详细的评估，包括外周血细胞和 口腔分泌物的蛋白质组学分析，最初复制CoV2的位置。我们将确定是否有可能 交叉反应的T细胞和分泌的IgA可能有助于这种早期的保护性免疫反应，如果存在的话 它们是否通过向B细胞提供更多的T细胞帮助来增强随后的体液免疫反应？这些 研究还将提供对CoV2的先天免疫反应的详细知识，以及这如何形成 体液免疫的性质和持续时间。我们的中心假设是外周血淋巴细胞和 在接触病毒时和发病前从个人口咽分泌物收集的 症状会表现出与病毒清除和病毒清除相关的先天和获得性免疫反应 预测是否形成有效的体液免疫和长期免疫记忆。 这一假说将通过探索以下目标来解决：i)评估早期免疫体液和 新冠肺炎确诊患者密切接触者对柯萨奇病毒2型的细胞免疫应答 新冠肺炎患者密切接触者的早期先天免疫反应 与体液免疫反应和病毒血症的关系；以及iii)检查体液免疫的早期驱动因素 关于免疫记忆的持久性和对疫苗的反应。这项全面的评估 早期先天感染与获得性免疫对长期记忆和免疫意志的影响 为开发高信息量和可扩展的血清学测试提供严格的基础。我们的方法 因此，通过开发和验证新的检测方法，对RFA-CA-20-039高度响应 同时测量早期感染CoV2的先天和获得性免疫反应；这种方法 将有助于确定与无症状和有症状相关的免疫参数和血清标志物 感染和疾病严重程度。

The duration and nature of humoral immunity to SARS-CoV-2 (CoV2) infection is poorly understood. Most studies have focused on the immune response in patients with clinical illness, but little is known about antibody response to CoV2 regarding the earliest immunological events immediately after exposure and prior to onset of illness or in asymptomatic individuals and how this impacts long-term immunological memory. This proposal addresses these gaps in our knowledge by prospectively following household contacts with clinical cases of CoV2 to determine innate and adaptive immune events associated with this early viral exposure over a 28 day period. Detailed evaluation of samples from these patients including RNAseq of peripheral blood cells and proteomic analysis of oral secretions, the site of initial CoV2 replication. We will determine whether potentially cross-reactive T cells and secretory IgA may contribute to this early protective immune response and if present do they enhance the subsequent humoral immune responses by providing greater T cell help to B cells. These studies will also provide a detailed knowledge of innate immune responses to CoV2 and how this shapes the nature and duration humoral immunity. Our central hypothesis is that peripheral blood lymphocytes and oropharyngeal secretions collected from individuals at the time of viral exposure and prior to onset of symptoms will show innate and adaptive immune responses that correlate with viral clearance and predict whether or not effective humoral immunity and long-term immunological memory develops. This hypothesis will be addressed by exploring the following aims; i) evaluating the early immune humoral and cellular immune responses to CoV2 in close contacts of individuals diagnosed with COVID-19; ii) to assess early innate immune responses in close contacts of individuals diagnosed with COVID-19 and assess their relationship with humoral immune responses and viremia; and iii) to examine early drivers of humoral immunity on the durability of immunological memory and responses to vaccines. This comprehensive evaluation of the relationships between early infection with innate and adaptive immune on long-term memory and immunity will provide a rigorous basis for the development of highly informative and scalable serological tests. Our approach is therefore highly responsive to RFA-CA-20-039, through the development and validation of novel assays that simultaneously measure innate and adaptive immune responses to CoV2 from early infection; this approach will help define immune parameters and serological markers associated with asymptomatic vs. symptomatic infection and disease severity.