JCI Insight. 2025 Mar 04. pii: e174600. [Epub ahead of print]
Yanying Yang,
Xiaoyan Li,
Fangming Liu,
Mingyue Ma,
Ying Yang,
Chengchao Ruan,
Yan Lu,
Xiaoyang Li,
Xiangdong Wang,
Yinghong Shi,
Zheng Zhang,
Hua Wang,
Zhouli Cheng,
Duojiao Wu.
This study aimed to explore the potential correlation between the metabolic intermediate L-2-hydroxyglutarate (L-2-HG) and T cell exhaustion, as well as the underlying mechanisms involved. In this study, we investigated the presence of exhausted T cells (Tex) in patients under certain conditions: HIV infection, chronic leukemia, and hepatocellular carcinoma. To gain insights into the epigenetic signatures and transcriptome alterations in Tex, we employed a combination of RNA-seq and ATAC-seq analyses. To evaluate the impact of L-2-HG on mitochondrial function, differentiation, and anti-tumor capacity of Tex, we utilized in vitro cell culture experiments and animal tumor models. We observed mitochondrial depolarization and metabolic dysfunction in Tex, accompanied by a significant reduction in the metabolic intermediate L-2-HG level. Moreover, altered epigenetic characteristics was observed in Tex, including a substantial increase in H3K27me3 abundance. Culturing Tex with L-2-HG demonstrated improved mitochondrial metabolism, reduced H3K27me3 abundance, and enhanced memory T cell differentiation. In the mouse melanoma tumor model, L-2-HG-treated CD8+T cells for adoptive therapy led to significantly reduced tumor volume and significantly enhanced effector function of T cells. The study revealed L-2-HG acted as an immune metabolite through epigenetic modifications of Tex.
Keywords: Cancer immunotherapy; Immunology; Metabolism; T cells