健康个体中SARS-CoV-2反应性记忆T细胞免疫研究

SARS-CoV-2 reactive memory T cell immunity in healthy individuals

目的 了解健康个体中的SARS-CoV-2反应性CD4+T细胞的记忆表型和功能。方法 使用SARS-CoV-2来源多肽刺激来自参与者的PBMC,通过胞内染色和流式细胞术检测SARS-CoV-2反应性记忆T细胞,并进行记忆表型分析,通过CBA检测SARS-CoV-2来源多肽刺激后的细胞因子分泌水平,初步评估SARS-CoV-2反应性记忆T细胞的功能。结果 40%(6/15)健康个体可检测到SARS-CoV-2反应性CD4+记忆T细胞,记忆表型分析显示其主要由中央记忆型T细胞组成(82.2%),其他记忆细胞占17.8%。与阴性对照相比,SARS-CoV-2来源多肽刺激后,IL-10分泌水平的下降具有统计学意义(P<0.05),IFNγ、TNFα、IL-2和IL-4分泌水平的差异不具有统计学意义。结论 健康个体中存在SARS-CoV-2反应性CD4+记忆T细胞。

Objective To understand the memory phenotype and function of SARS-CoV-2 reactive CD4+ T cells in healthy individuals.Methods In this study, SARS-CoV-2-derived peptides were used to stimulate PBMC from participants.SARS-CoV-2 reactive memory T cells were detected by intracellular staining and flow cytometry, and memory phenotype analysis was performed.CBA was used to detect cytokine secretion after SARS-CoV-2-derived peptides stimulation to evaluate the function of SARS-CoV-2 reactive memory T cells.Results We found that SARS-CoV-2 reactive CD4+ memory T cells could be detected in 40%(6/15) healthy donors.Phenotypic analysis of memory showed that these T cells were mainly composed of central memory T cells(82.2%),and other memory cells accounted for 17.8%.Compared with negative control, IL-10 was significantly decreased after stimulation of SARS-CoV-2-derived peptides(P<0.05),while the secretion of IFNγ,TNFα,IL-2 and IL-4 showed no significant difference.Conclusions SARS-CoV-2 reactive CD4+ memory T cells are present in healthy individuals from China.