Tong Zhonghua, Yan Xiangyu, Chen Tao, Song Weijun, Su Di, Wang Naixin, Zhang Yafei, Kong Yingjin, Wang Dongni, Wang Penghe, Chen Yujia, Wang Xiaoqi, Cui Jingxuan, Sui Jiayu, Liu Shuang, Li Yanxi, Yang Qiannan, Zheng Ziqi, Jin Zexi, Li Yunling, Liu Fang, Li Jiaxuan, Qi Lishuang, Deng Jiaxing, Li Zhaoying, Yang Shuang, Jia Haibo, Ji Yong, Zhang Maomao, Yu Bo
Departments of Cardiology (Z.T., X.Y., T.C., W.S., D.S., N.W., Y.Z., Y.K., D.W., P.W., Y.C., X.W., J.C., J.S., S.L., Yanxi Li, Q.Y., Z.Z., Z.J., F.L., Z.L., S.Y., H.J., M.Z., B.Y.), The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China.
The Key Laboratory of Myocardial Ischemia, Chinese Ministry of Education, Harbin, Heilongjiang, China (Z.T., X.Y., T.C., W.S., D.S., N.W., Y.Z., Y.K., D.W., P.W., Y.C., X.W., J.C., J.S., S.L., Yanxi Li, Q.Y., Z.Z., Z.J., F.L., Z.L., S.Y., H.J., M.Z., B.Y.).
Circulation. 2025 Aug 5. doi: 10.1161/CIRCULATIONAHA.125.073836.
Acute myocarditis (AM), particularly fulminant myocarditis (FM), is an infrequent but life-threatening cardiac inflammation, with limited effective precision-targeted treatments available. This urgent clinical challenge has prompted further investigations into the mechanisms underlying this pathology to develop novel therapeutic approaches.
We enrolled 40 patients diagnosed with AM (24 mild, 16 fulminant) between December 2022 and November 2023. Using a multi-omics approach, we analyzed peripheral blood mononuclear cells and plasma-integrated single-cell RNA sequencing, single-cell T-cell receptor sequencing, cytometry by time of flight, and Olink proteomics to identify specific pathogenic immune subsets and molecular alterations. In vitro experiments validated the function and inducing signals of identified pathogenic subsets. In coxsackievirus B3-induced FM mice, cytometry by time of flight analysis was performed on peripheral blood mononuclear cells and cardiac infiltrating immune cells. Pharmacological blockade of key molecular was tested to assess potential therapeutic efficacy.
We identified that a specialized type of CD8 effector T cells, CD57CD8 T cells with high cytotoxicity and migration potential, were significantly enriched and exhibited large clonal expansion in AM. Differential expression analysis revealed upregulation of natural killer-like receptor genes in CD57CD8 effector T cells from FM compared with mild cases, which was positively associated with enhanced cytotoxicity and migration potential. In vitro experiments confirmed the existence of circulating CD57CD8 effector T cells with high cytotoxic degranulation and migration potential inducing cardiomyocyte apoptosis, supporting their cardiac migration and cardiomyocyte cytotoxicity in pathogenesis. Elevated circulating interleukin (IL)-18 levels in patients with AM induced the functional differentiation of CD57CD8 effector T cells. In addition, increased proinflammatory CXCL8CD14 monocytes potentially contributed to increasing IL-18 levels and crosstalk with CD57CD8 effector T cells. In FM mice, we observed the analogous expansions of CD57CD8 effector T cells and CXCL2LY6C monocytes in both blood and hearts, accompanied by elevated plasma IL-18 levels. Disrupting the pathogenic axis involving proinflammatory monocytes, IL-18 signaling, and CCR5-mediated cardiac recruitment significantly alleviated FM in mice.
Our study provides a comprehensive immune landscape for understanding the pathogenesis of AM, especially in FM, highlighting clonal CD57CD8 effector T cells with high cytotoxicity and migration potential, along with their upstream inflammatory signals, as potential therapeutic targets for mitigating immune-related cardiac damage in AM management, especially in FM.
急性心肌炎（AM），尤其是暴发性心肌炎（FM），是一种罕见但危及生命的心脏炎症，可用的有效精准靶向治疗有限。这一紧迫的临床挑战促使人们进一步研究这种病理状况的潜在机制，以开发新的治疗方法。
我们纳入了2022年12月至2023年11月期间诊断为AM的40例患者（24例轻度，16例暴发性）。我们采用多组学方法，分析外周血单个核细胞和血浆，整合单细胞RNA测序、单细胞T细胞受体测序、飞行时间流式细胞术和Olink蛋白质组学，以识别特定的致病性免疫亚群和分子改变。体外实验验证了所识别的致病性亚群的功能和诱导信号。在柯萨奇病毒B3诱导的FM小鼠中，对外周血单个核细胞和心脏浸润免疫细胞进行飞行时间流式细胞术分析。测试关键分子的药物阻断以评估潜在的治疗效果。
我们发现一种特殊类型的CD8效应T细胞，即具有高细胞毒性和迁移潜力的CD57CD8 T细胞，在AM中显著富集并表现出大量克隆扩增。差异表达分析显示，与轻度病例相比，FM患者CD57CD8效应T细胞中自然杀伤样受体基因上调，这与细胞毒性和迁移潜力增强呈正相关。体外实验证实，存在具有高细胞毒性脱颗粒和迁移潜力的循环CD57CD8效应T细胞，可诱导心肌细胞凋亡，支持它们在发病机制中的心脏迁移和心肌细胞细胞毒性。AM患者循环白细胞介素（IL）-18水平升高诱导了CD57CD8效应T细胞的功能分化。此外，促炎CXCL8CD14单核细胞增加可能有助于提高IL-18水平，并与CD57CD8效应T细胞发生相互作用。在FM小鼠中，我们观察到血液和心脏中CD57CD8效应T细胞和CXCL2LY6C单核细胞类似的扩增，同时血浆IL-18水平升高。破坏涉及促炎单核细胞、IL-18信号传导和CCR5介导的心脏募集的致病轴可显著减轻小鼠的FM。
我们的研究为理解AM，尤其是FM的发病机制提供了全面的免疫图谱，突出了具有高细胞毒性和迁移潜力的克隆性CD57CD8效应T细胞及其上游炎症信号，作为减轻AM，尤其是FM中免疫相关心脏损伤的潜在治疗靶点。
