DataSheet_1_In-Depth Profiling of T-Cell Responsiveness to Commonly Recognized CMV Antigens in Older People Reveals Important Sex Differences.pdf

The impact of biological sex on T-cell immunity to Cytomegalovirus (CMV) has not been investigated in detail with only one published study comparing CMV-specific T-cell responses in men and women. Many studies, however, have shown an association between CMV infection and immunosenescence, with broad effects on peripheral blood lymphocyte subsets as well as the T and B-cell repertoires. Here, we provide a detailed analysis of CMV-specific T-cell responses in (n=94) CMV+ older people, including 47 women and 47 men aged between 60 and 93 years. We explore sex differences with respect to 16 different CMV proteins arranged in 14 peptide pools (overlapping peptides). Following ex vivo stimulation, CD4 and CD8 T-cells producing IFN-γ, TNF, and IL-2 were enumerated by flow-cytometry (intracellular cytokine staining). T-cell responses were evaluated in terms of each cytokine separately or in terms of cytokines produced simultaneously (polyfunctionality). Surface memory phenotype and CD3 downmodulation were assessed in parallel. The polyfunctionality index and a memory subset differentiation score were used to identify associations between response size, cytokine production, polyfunctionality, and memory subset distribution. While no significant sex differences were found with respect to overall CMV target protein selection, the T-cell response in men appeared more focused and accompanied by a more prominent accumulation of CMV-specific memory CD4 and CD8 T-cells. T-cell polyfunctionality and differentiation were similar in the sexes, however, CMV-specific T-cells in men produced more pro-inflammatory cytokines. Particularly, TNF production by CD4 T-cells was stronger in men than in women. Also, compared with women, men had larger responses to CMV proteins with immediate-early/early kinetics than women, which might have been driven by CMV reactivation. In conclusion, the CMV-specific T-cell response in men was larger and more pro-inflammatory than in women. Our findings may help explain sex differences in CMV-associated pathologies.

迄今尚未有针对生物性别对巨细胞病毒（Cytomegalovirus, CMV）特异性T细胞免疫影响的详细研究，目前仅发表过一项对比男性与女性CMV特异性T细胞应答的研究。不过，诸多研究已证实CMV感染与免疫衰老存在关联，其对外周血淋巴细胞亚群及T、B细胞受体库均具有广泛影响。本研究对94名CMV血清阳性（CMV+）老年受试者的CMV特异性T细胞应答展开了详细分析，受试者年龄介于60至93岁，其中女性47名、男性47名。研究针对由14组肽库（含重叠肽（overlapping peptides））覆盖的16种CMV蛋白，探究了相关性别差异。经离体刺激（ex vivo stimulation）后，研究通过流式细胞术（flow cytometry）结合胞内细胞因子染色（intracellular cytokine staining）法，对分泌IFN-γ、TNF及IL-2的CD4、CD8 T细胞进行了计数。本研究从单种细胞因子分泌情况，以及同时分泌多种细胞因子的T细胞（即T细胞多功能性（polyfunctionality））两个维度对T细胞应答进行评估，并同步检测了T细胞表面记忆表型及CD3分子下调情况。研究采用多功能性指数与记忆亚群分化评分，分析了应答强度、细胞因子分泌水平、T细胞多功能性与记忆亚群分布之间的关联。结果显示，尽管在整体CMV靶蛋白选择层面未发现显著性别差异，但男性的T细胞应答更为聚焦，且伴随CMV特异性记忆CD4、CD8 T细胞的积累更为显著。不过，两性的T细胞多功能性与分化程度并无明显差异，但男性的CMV特异性T细胞分泌的促炎细胞因子水平更高；具体而言，男性CD4 T细胞分泌的TNF水平显著高于女性。此外，相较于女性，男性对具有即刻早期/早期动力学特征的CMV蛋白的应答强度更高，该现象或由CMV再激活所介导。综上，男性的CMV特异性T细胞应答强度更高且促炎特性更强。本研究结果或有助于解释CMV相关疾病中的性别差异。