Enabling risk-based testing through characterization of environmentally induced immune dysregulation and susceptibility to the SARS-CoV2 virus and COVID-19

在2022财年，我们继续将免疫毒理学研究项目的重点放在体外方法上。一项主要工作涉及使用体外人全血培养系统，研究个体间易感性因素和环境风险因素（如暴露于多芳烃）如何影响对病毒感染（SARS-CoV-2和流感）的反应。终点包括淋巴细胞毒性、细胞因子释放和自然杀伤细胞活性。在2022财年，BRT对从商业来源购买的200份血液样本进行了这些检测。这些数据目前正在报告和出版之前进行分析。在FY22增加体外方法工具箱的努力导致了基于流式细胞术的测定的发展，以测量体外病毒抗原刺激后的t细胞活化。BRT继续扩大工具箱，目前正在测试这种培养系统，以促进对病毒抗原的体液抗体介导免疫的询问。我们已经开始了一种免疫抑制化合物的初步体外研究，该化合物将作为体外PAC-MAP研究的阳性对照。来自这些研究的数据将与先前根据本合同收集的小鼠体内数据相对照，并用于确定人类相关性，并建立使用体外系统可以产生的数据的科学信心。这个体外工具箱对于鉴定有可能调节人体免疫功能的化学物质至关重要，并将使国家毒理学规划处于该领域测试的前沿。

In FY 22 we continued to focus the immunotoxicology research program on in vitro approaches. A major effort involved investigating how interindividual susceptibility factors and environmental risk factors such as exposure to polyaromatic hydrocarbons impact the response to viral infection (SARS-CoV-2 and Influenza), using an in vitro human whole blood culture system. Endpoints include lymphocytotoxicity, cytokine release, and Natural Killer cell activity. In FY22, BRT performed these assays for 200 blood samples purchased from commercial sources. The data are currently being analyzed prior to reporting and publication. Efforts in FY22 to add to this toolbox of in vitro approaches resulted in the development of a flow cytometry-based assay to measure T-cell activation following in vitro stimulation with viral antigens. BRT continues to expand the toolbox and is currently testing this culture system to facilitate interrogation of humoral antibody mediated immunity to viral antigens. We have begun preliminary in vitro studies with an immunosuppressive compound that will serve as a positive control for the in vitro PAC-MAP studies. The data from these studies will be referenced against mouse in vivo data previously collected under this contract and serve to anchor human relevance and establish scientific confidence in the data that can be generated using the in vitro system. This in vitro toolbox will be critically important to identify chemicals that have the potential to modulate immune function in humans and will position NTP at the cutting edge of testing in this field.