Sex, obesity, immunometabolism, and viral persistence in post-acute sequelae of SARS-CoV-2 infection

总结 在SARS-CoV-2感染后，有相当比例的人出现持续的症状或健康问题。 并发症，通常被称为“长期COVID”或COVID-19的急性后遗症（PASC）。宿主，病毒 对影响PASC发展的环境因素认识不足，阻碍了PASC的发展 of therapeutics治疗for patients病人. PASC也没有生物标志物，这使得PASC的发展变得复杂 诊断在拟议的工作中，我们将建立在初步数据显示免疫和代谢 与PASC的特定症状相关的失调。我们召集了一个跨学科的 在SARS-CoV-2病毒学、病毒免疫、RNA病毒持久性、切割、 基于边缘组织的病毒检测，COVID-19动物模型，队列方法学，传染病 诊断、高维单细胞数据分析和呼吸道病毒感染中基于性别的差异。 我们的团队包括NIH资助的COVID-19血清学卓越中心的主要研究者， 四项大型COVID-19临床研究，招募参与者超过1500人，纵向血液和呼吸系统 从症状发作后2天至18个月后的粘膜取样结合症状调查 症状发作。我们将研究持续性病毒抗原或RNA，宿主免疫反应，性别， 肥胖和PASC。我们的中心假设是，不同的和持久的免疫代谢谱是 与特定的后COVID状况相关。在目标1中，我们将使用免疫代谢高维流 细胞计数、靶向代谢基因表达谱分析和功能测定以及单细胞RNA测序 剖析推动这些独特人群分化和功能的代谢和免疫程序， 在来自具有不同PASC症状和后遗症的个体以及具有完全PASC症状和后遗症的个体的纵向样本中， 从COVID-19中恢复过来。在目标2中，我们将确定PASC的特定症状和后遗症是否 与SARS-CoV-2特异性B和T细胞应答的长期演变相关，提示病毒抗原 或RNA持久性，并由肥胖促进。在目标3中，我们将使用我们新的SARS-CoV-2小鼠模型， 评估SARS-CoV-2 RNA或抗原在多个器官中持续存在的性别差异，这可能导致 组织中的免疫代谢失调，并与小鼠PASC的行为体征相关。通过 在本提案中概述的实验中，我们将讨论某种形式的SARS-CoV-2持久性是否 导致PASC，或者如果PASC完全是远程病毒感染的结果， 巨大的临床意义。

Summary After SARS-CoV-2 infection, a significant percentage of people develop persistent symptoms or health complications, often referred to as ‘long COVID’ or post-acute sequelae of COVID-19 (PASC). The host, virus and environmental factors affecting the development of PASC are not well known, which hinders development of therapeutics for patients. There also are no biomarkers for PASC, which complicates development of diagnostics. In the proposed work, we will build on preliminary data showing immune and metabolic dysregulation correlating with specific symptoms of PASC. We have assembled a cross-disciplinary collaborative team with global expertise in SARS-CoV-2 virology, viral immunity, RNA virus persistence, cutting edge tissue-based viral assays, animal models of COVID-19, cohort methodology, infectious diseases diagnostics, high-dimensional single cell data analysis, and sex-based differences in respiratory viral infection. Our team includes the primary investigators of an NIH-funded COVID-19 Serology Center of Excellence and four large COVID-19 clinical studies with > 1500 enrolled participants and longitudinal blood and respiratory mucosal sampling coupled with symptom surveys from 2 days after symptom onset through 18 months after symptom onset. We will study the intersection of persistent viral antigen or RNA, host immune response, sex, obesity, and PASC. Our central hypothesis is that distinct and persistent immune metabolic profiles are associated with specific post-COVID conditions. In Aim 1, we will use immune-metabolic high-dimensional flow cytometry, targeted metabolic gene expression profiling and functional assays, and single cell RNA sequencing to dissect the metabolic and immune programs driving differentiation and function of these unique populations in longitudinal samples from individuals with distinct PASC symptoms and sequelae and those with complete recovery from COVID-19. In Aim 2, we will determine whether specific symptoms and sequelae of PASC are associated with prolonged evolution of SARS-CoV-2-specific B and T cell responses suggestive of viral antigen or RNA persistence and facilitated by obesity. In Aim 3, we will use our novel mouse model of SARS-CoV-2 to evaluate sex differences in the persistence of SARS-CoV-2 RNA or antigen in multiple organs, which may lead to immune-metabolic dysregulation in tissues and correlate with behavioral signs of PASC in mice. Through the experiments outlined in this proposal, we will address whether some form of SARS-CoV-2 persistence contributes to PASC or if PASC is entirely a consequence of a remote virus infection, a question with enormous clinical implications.