Increased levels of arginine in T cells result in the inhibition of glucose uptake and the promotion of mitochondrial oxidative metabolism. Concurrently, arginine modulates the conformation of several proteins involved in chromatin regulation. Together, these alterations in cell metabolism and perhaps gene expression driven by arginine promote the acquisition of a memory phenotype in T cells. This phenotype results in increased T cell survival, persistence, and an improved antitumor response.