- Zhu, Hao-Xian;
- Yang, Shu-Han;
- Gao, Cai-Yue;
- Bian, Zhen-Hua;
- Chen, Xiao-Min;
- Huang, Rong-Rong;
- Meng, Qian-Li;
- Li, Xin;
- Jin, Haosheng;
- Tsuneyama, Koichi;
- Han, Ying;
- Li, Liang;
- Zhao, Zhi-Bin;
- Gershwin, M;
- Lian, Zhe-Xiong
Primary biliary cholangitis (PBC) is a cholestatic autoimmune liver disease characterized by autoreactive T cell response against intrahepatic small bile ducts. Here, we use Il12b-/-Il2ra-/- mice (DKO mice) as a model of autoimmune cholangitis and demonstrate that Cd8a knockout or treatment with an anti-CD8α antibody prevents/reduces biliary immunopathology. Using single-cell RNA sequencing analysis, we identified CD8+ tissue-resident memory T (Trm) cells in the livers of DKO mice, which highly express activation- and cytotoxicity-associated markers and induce apoptosis of bile duct epithelial cells. Liver CD8+ Trm cells also upregulate the expression of several immune checkpoint molecules, including PD-1. We describe the development of a chimeric antigen receptor to target PD-1-expressing CD8+ Trm cells. Treatment of DKO mice with PD-1-targeting CAR-T cells selectively depleted liver CD8+ Trm cells and alleviated autoimmune cholangitis. Our work highlights the pathogenic role of CD8+ Trm cells and the potential therapeutic usage of PD-1-targeting CAR-T cells.