Enhancing tumor response to adoptive T cell therapy by targeting PHD2/3 in CD8 T cells
In our study, we utilized cutting-edge CrisPR-Cas9 technology to evaluate the effects of deleting prolyl hydroxylase domain-containing enzymes (PHD) 2 and 3, which stabilizes HIF-1 signaling, in CD8 T cells that have already undergone differentiation and activation, mirroring the conditions encountered in clinical settings. Our study revealed a significant boost in T-cell activation and effector functions after PHD2/3 deletion, and conclusively established its dependence on HIF-1. This improvement in CD8 T cell performance translated into a remarkable enhancement in the response to adoptive T cell therapy, across various tumor models, even including those reported to be extremely resistant to immunotherapeutic interventions. Furthermore, our data provide compelling evidence that the increased effector functions observed in PHD-deficient (KO) CD8 T cells are intricately linked to an increased glycolytic flux. These findings hold significant promise for advancing CD8 T -cell based therapies and overcoming the immune suppression barriers within challenging tumor microenvironments. Overall design: To decipher the impact of HIF-1 signaling on the function of CD8 T cells, we generated activated murin TCRP1A CD8 T lymphocytes in which HIF-1a or PHD2/3 have been knock-out by Crispr-Cas9 nucleofection technology. We then performed RNA-seq analysis on HIF-1a KO, PHD2/3 KO and WT (control) CD8 T cells which have been incubated in norrmoxia or hypoxia for 48 hours. Samples were analysed in biological triplicates.