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Adoptive immunotherapies using T cells genetically redirected with a chimeric antigen receptor (CAR) or T cell receptor (TCR) are entering mainstream clinical practice. Despite encouraging results, some patients do not respond to current therapies. In part, this phenomenon has been associated with infusion of reduced numbers of early memory T cells. Herein, we report that AKT signaling inhibition is compatible with CAR and TCR retroviral transduction of human T cells while promoting a CD62L-expressing central memory phenotype. Critically, this intervention did not compromise cell yield. Mechanistically, disruption of AKT signaling preserved MAPK activation and promoted the intranuclear localization of FOXO1, a transcriptional regulator of T cell memory. Consequently, AKT signaling inhibition synchronized the transcriptional profile for FOXO1-dependent target genes across multiple donors. Expression of an AKT-resistant FOXO1 mutant phenocopied the influence of AKT signaling inhibition, while addition of AKT signaling inhibition to T cells expressing mutant FOXO1 failed to further augment the frequency of CD62L-expressing cells. Finally, treatment of established B cell acute lymphoblastic leukemia was superior using anti-CD19 CAR-modified T cells transduced and expanded in the presence of an AKT inhibitor compared with conventionally grown T cells. Thus, inhibition of signaling along the PI3K/AKT axis represents a generalizable strategy to generate large numbers of receptor-modified T cells with an early memory phenotype and superior antitumor efficacy.

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.