Properties of end-stage human T cells defined by CD45RA re-expression

► CD45RA re-expressing T cells are pre-senescent memory T cells. ► Although non-proliferative, these cells exert potent effector function. ► CD45RA re-expressing T cells reside in skin, BM and spleen but not lymph nodes. ► Cell generation is cytokine driven and antigen independent. ► CD45RA re-expressing cell cycle block is maintained by inhibitory signalling.