Valenzuela-Pérez Lucía, Kim Lee Hyun Se, Bayer Rachel L, Mishra Shravan K, Washington Alexander M, Guo Qianqian, Herman Adam, Graham Rondell P, Sidahmed Malaz M, Ssali Edward, Hassan Adna A, Dinc Ece Janet, Pavelko Kevin D, Gores Gregory J, Starlinger Patrick, Revelo Xavier S, Ibrahim Samar H, Kostallari Enis, Bamidele Adebowale O, Hirsova Petra
bioRxiv. 2025 Jul 3:2025.06.27.660220. doi: 10.1101/2025.06.27.660220.
Unresolved inflammation and fibrosis are the two key features of metabolic dysfunction-associated steatohepatitis (MASH), a progressive form of steatotic liver disease that can evolve into cirrhosis and liver cancer. Although innate immunity has been well studied in MASH, the role of CD4⁺ T cells remains underexplored despite their potential to coordinate immune responses by providing help to other immune cells, promoting inflammation, or regulating immune activity through effector and regulatory subsets. To better understand the role of CD4 T cells in the pathogenesis of MASH, we comprehensively characterized hepatic CD4 T cells in murine and human MASH at a single-cell protein, transcriptional, and functional level. Mass cytometry and CITE-sequencing revealed a marked shift in intrahepatic CD4⁺ T-cell composition in MASH, with enrichment of Th1, regulatory, and cytotoxic CD4⁺ T cells. Similar phenotypic changes were mirrored in the peripheral blood and validated in human MASH samples. Functional assays demonstrated increased production of IFNγ and TNFα by hepatic CD4⁺ T cells, highlighting their proinflammatory effector activity. Transcriptomic profiling identified Tnfrsf4 (OX40) upregulation in hepatic CD4⁺ T cells during MASH. Therapeutic blockade of the OX40L-OX40 axis reversed hepatic fibrosis and improved histologic disease scores in mice with established MASH, and also decreased inflammatory markers in a human liver model. Together, these studies provide a proteogenomic single-cell atlas for hepatic CD4⁺ T cells and uncover a CD4⁺ T cell-dependent immunopathogenic circuit as a promising immunotherapeutic target to alleviate MASH and liver fibrosis.
未解决的炎症和纤维化是代谢功能障碍相关脂肪性肝炎（MASH）的两个关键特征，MASH是一种进行性脂肪性肝病，可发展为肝硬化和肝癌。尽管先天性免疫在MASH中已得到充分研究，但CD4⁺T细胞的作用仍未得到充分探索，尽管它们有可能通过向其他免疫细胞提供帮助、促进炎症或通过效应和调节亚群调节免疫活动来协调免疫反应。为了更好地理解CD4⁺T细胞在MASH发病机制中的作用，我们在单细胞蛋白质、转录和功能水平上全面表征了小鼠和人类MASH中的肝脏CD4⁺T细胞。质谱流式细胞术和CITE测序显示，MASH中肝内CD4⁺T细胞组成发生了显著变化，Th1、调节性和细胞毒性CD4⁺T细胞富集。外周血也出现了类似的表型变化，并在人类MASH样本中得到验证。功能分析表明，肝脏CD4⁺T细胞产生的IFNγ和TNFα增加，突出了它们的促炎效应活性。转录组分析确定了MASH期间肝脏CD4⁺T细胞中Tnfrsf4（OX40）上调。对OX40L-OX40轴的治疗性阻断可逆转已建立MASH的小鼠的肝纤维化并改善组织学疾病评分，还可降低人类肝脏模型中的炎症标志物。总之，这些研究为肝脏CD4⁺T细胞提供了一个蛋白质基因组单细胞图谱，并揭示了一个依赖CD4⁺T细胞的免疫致病回路，作为缓解MASH和肝纤维化的一个有前景的免疫治疗靶点。
