Fueling Function Over Expansion in T Cells

Vertebrates generate millions of unique T cell receptors during T cell development, ensuring that the immune system can recognize any number of potential pathogens. A compromise for this extraordinary molecular diversity is that the T cell population of a given individual contains only a handful of cells that can recognize any particular foreign invader. To solve this problem, T cells can undergo extraordinary proliferation in response to infection ( 1 ). Upon activation, they adopt specialized metabolic programs, such as aerobic glycolysis [the Warburg effect ( 2 – 5 )], which has long been thought to meet the biosynthetic and bioenergetic requirements associated with rapid expansion ( 2 ). But a recent study by Chang et al. ( 6 ) raises questions about this model and suggests instead that aerobic glycolysis is necessary for T cell effector function rather than proliferation.