A VHL-HIF signaling axis orchestrates invariant natural killer T cell development and fate decisions.

Invariant natural killer T (iNKT) cells are a subset of innate-like T lymphocytes that play important roles in immune responses. The mechanisms underlying the stage-specific development and differentiation of iNKT effector subsets are not fully elucidated. Here, using Zbtb16-Cre-driven conditional knockout mice, we found that conditional deletion of the E3 ligase Von Hippel-Lindau (VHL) resulted in impaired terminal maturation of iNKT cells and attenuated lineage specification of the iNKT2 and iNKT17 subsets. VHL deficiency disrupted iNKT cell-mediated tumor surveillance, thereby promoting B16F10 pulmonary metastasis. VHL ablation triggered hypoxia-inducible factor 1α (HIF1α) accumulation, which upregulated Bnip3 expression and caused aberrant reactive oxygen species (ROS) accumulation, thus driving apoptosis. HIF1α upregulation suppressed iNKT2 differentiation by impairing mitochondrial respiration, whereas HIF2α-mediated IL2RA-STAT5 signaling inhibited iNKT17 specification. Together, our work identifies the VHL-HIF axis as a fundamental determinant of iNKT cell differentiation and function, offering a mechanistic basis for harnessing iNKT cells in cancer immunotherapy.