Preclinical Study Identifies GALE as Checkpoint Restricting Vγ9Vδ2 T Cell Killing

Using a genome-wide CRISPR screen, researchers have identified UDP-galactose 4-epimerase (GALE) as a tumor-intrinsic checkpoint that restricts Vγ9Vδ2 T cell-mediated cancer cell killing. Vγ9Vδ2 T cells mediate HLA-independent targeting of tumor cells, offering distinct opportunities for cancer immunotherapy, although their therapeutic efficacy has remained limited. The investigation demonstrated that GALE, a key nucleotide-sugar metabolic enzyme controlling the interconversion of UDP-galactose and UDP-glucose, supports protein glycosylation and cell-surface glycan remodeling that promotes tumor resistance to Vγ9Vδ2 T cell cytotoxicity.

Mechanistically, the study revealed that GALE promotes complex N-glycosylation of CD155 and CEACAM1 on tumor cells. This remodeling favors their engagement with the inhibitory receptors TIGIT and TIM3, respectively, while limiting the binding of CD155 to the activating receptor CD226. Further experimental observations showed that enzymatic activity of GALE drives resistance to Vγ9Vδ2 T cell killing, whereas galactose restores resistance in GALE-deficient cells, demonstrating that CEACAM1 and CD155 complex N-glycans impair immune killing.

In preclinical evaluations, the loss of GALE potentiated Vγ9Vδ2 T cell-mediated tumor killing across multiple mouse models and in patient-derived organoids from colorectal cancer, with Vγ9Vδ2 T cells suppressing GALE-deficient colorectal cancer in vivo. In addition, multiomics analyses identified drivers of GALE overexpression in tumors. The authors noted that these findings reveal how nucleotide-sugar metabolism shapes tumor–immune communication through complex N-glycan remodeling, identifying GALE and its downstream receptor–ligand interactions as potential therapeutic targets for enhancing Vγ9Vδ2 T cell antitumor activity in future translational research.

Subject of Research: Regulation of Vγ9Vδ2 T cell antitumor killing by metabolic enzyme GALE

Article Title: GALE is a tumor-intrinsic checkpoint of Vγ9Vδ2 T cell-mediated killing

Article References: Shan, Z., Wang, D., Zheng, Z., Ye, Z., Mao, S., Xie, L., Li, Y., Guo, Y., Weng, L., Wu, Q., Wang, Y., Ran, Q., Yang, Y., Niu, T., Li, L., Luo, D., Weng, J., Yu, L., Wei, L., … Wang, P. (2026). GALE is a tumor-intrinsic checkpoint of Vγ9Vδ2 T cell-mediated killing. Nature Cancer. https://doi.org/10.1038/s43018-026-01249-5

Image Credits: AI Generated

DOI: 10.1038/s43018-026-01249-5

Keywords: GALE, Vγ9Vδ2 T cells, immune checkpoints, cancer immunotherapy, CRISPR screen, protein glycosylation, CD155, CEACAM1, tumor-intrinsic, checkpoint, cell-mediated, killing