Hallmarks of T cell aging

The aged adaptive immune system is characterized by progressive dysfunction as well increased autoimmunity. This decline responsible for elevated susceptibility to infection and cancer, decreased vaccination efficacy. Recent evidence indicates that CD4+ T cell–intrinsic alteratins contribute chronic inflammation are sufficient accelerate an organism-wide aging phenotype, supporting the idea cell plays a major role in body-wide deterioration. In this Review, we propose ten molecular hallmarks represent common denominators of aging. These grouped into four primary (thymic involution, mitochondrial dysfunction, genetic epigenetic alterations, loss proteostasis) secondary (reduction TCR repertoire, naive–memory imbalance, senescence, lack effector plasticity), together they explain manifestation two integrative (immunodeficiency inflammaging). A challenge now weighing relative impact these on understanding their interconnections, with final goal defining targets interventions process. Mittelbrunn Kroemer