Metabolism, migration and memory in cytotoxic T cells

Abstract
The serine/threonine kinase AKT does not have an obligatory role in controlling T cell metabolism. Members of the AMP-activated protein kinase (AMPK) family have a role in T cell metabolism. AKT controls T cell migration by regulating the expression of multiple adhesion and chemokine receptors that are crucial for homing to lymphoid tissues. Distinct magnitudes of AKT activity are required for different AKT functions — T cell proliferation versus T cell migration. The energy-sensing kinases mammalian target of rapamycin (mTOR) and AMPK may control T cell memory through a mechanism involving the control of T cell migration rather than T cell metabolism. Differential levels of mTOR and AKT activity resulting from differences in T cell receptor and/or cytokine signalling strength could determine whether naive CD8+ T cells differentiate into effector cells or memory cells.