Naive CD8 + T cells rely upon oxidation of fatty acids as a primary source of energy. After antigen encounter, T cells shift to a glycolytic metabolism to sustain effector function. It is unclear, however, whether changes in glucose metabolism ultimately influence the ability of activated T cells to become long-lived memory cells. We used a fluorescent glucose analog, 2-NBDG, to quantify glucose uptake in activated CD8 + T cells. We found that cells exhibiting limited glucose incorporation had a molecular profile characteristic of memory precursor cells and an increased capacity to enter the memory pool compared with cells taking up high amounts of glucose. Accordingly, enforcing glycolytic metabolism by overexpressing the glycolytic enzyme phosphoglycerate mutase-1 severely impaired the ability of CD8 + T cells to form long-term memory. Conversely, activation of CD8 + T cells in the presence of an inhibitor of glycolysis, 2-deoxyglucose, enhanced the generation of memory cells and antitumor functionality. Our data indicate that augmenting glycolytic flux drives CD8 + T cells toward a terminally differentiated state, while its inhibition preserves the formation of long-lived memory CD8 + T cells. These results have important implications for improving the efficacy of T cell-based therapies against chronic infectious diseases and cancer.

Somatic gene mutations can alter the vulnerability of cancer cells to T cell-based immunotherapies. To mimic loss-of-function mutations involved in resistance to these therapies, we perturbed genes in tumour cells using a genome-scale CRISPR-Cas9 library comprising ~123,000 single guide RNAs, and profiled genes whose loss in tumour cells impaired the effector function of CD8+ T cells (EFT). We correlated these genes with cytolytic activity in ~11,000 patient tumours from The Cancer Genome Atlas. Among the genes validated using different cancer cell lines and antigens, we identified multiple loss-of-function mutations in APLNR, encoding Apelin receptor, in patient tumours refractory to immunotherapy. We show that APLNR interacts with JAK1, modulating interferon-gamma responses in tumours, and its functional loss reduces the efficacy of adoptive cell transfer and checkpoint blockade immunotherapies in murine models. Collectively, our study links the loss of essential genes for EFT with the resistance or non-responsiveness of cancer to immunotherapies.

Tumours progress despite being infiltrated by tumour-specific effector T cells1. Tumours contain areas of cellular necrosis, which is associated with poor survival in a variety of cancers2. Here, we show that necrosis releases an intracellular ion, potassium, into the extracellular fluid of mouse and human tumours causing profound suppression of T cell effector function. We find that elevations in the extracellular potassium concentration [K + ]e act to impair T cell receptor (TCR)-driven Akt-mTOR phosphorylation and effector programmes, this potassium-mediated suppression of Akt-mTOR signalling and T cell function is dependent upon the activity of the serine/threonine phosphatase PP2A3,4. While the suppressive effect mediated by elevated [K + ]e is independent of changes in plasma membrane potential (V m ), it does require an increase in intracellular potassium ([K + ]i). Concordantly, ionic reprogramming of tumour-specific T cells through overexpression of the potassium channel K v 1.3 lowers [K + ]i and improves effector Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use