Figure 4. T cell metabolic fitness and anti-tumor immunity.

Effector T cells require high levels of glucose and amino acid uptake and are inhibited by lactate and other metabolic waste products. Solid tumor that consume nutrients and accumulate waste products may limit the capacity of T cells to mount an anti-tumor immune response. Blockade of immune checkpoint modulatory signals, such as inhibition of PD-1 or CTLA4, can enhance effector T cell signaling and metabolism to improve T cell metabolic fitness and capacity to compete for nutrients in increasingly challenging metabolic environments.