IFN-γ regulates CD8(+) memory T cell differentiation and survival in response to weak, but not strong, TCR signals


  • D. Stoycheva
  • K. Deiser
  • L. Stärck
  • G. Nishanth
  • D. Schlüter
  • W. Uckert
  • T. Schüler


  • Journal of Immunology


  • J Immunol 194 (2): 553-559


  • In response to primary Ag contact, naive mouse CD8+ T cells undergo clonal expansion and differentiate into effector T cells. After pathogen clearance, most effector T cells die, and only a small number of memory T cell precursors (TMPs) survive to form a pool of long-lived memory T cells (TMs). Although high- and low-affinity CD8+ T cell clones are recruited into the primary response, the TM pool consists mainly of high-affinity clones. It remains unclear whether the more efficient expansion of high-affinity clones and/or cell-intrinsic processes exclude low-affinity T cells from the TM pool. In this article, we show that the lack of IFN-gammaR signaling in CD8+ T cells promotes TM formation in response to weak, but not strong, TCR agonists. The IFN-gamma-sensitive accumulation of TMs correlates with reduced mammalian target of rapamycin activation and the accumulation of long-lived CD62LhiBcl-2hiEomeshi TMPs. Reconstitution of mammalian target of rapamycin or IFN-gammaR signaling is sufficient to block this process. Hence, our data suggest that IFN-gammaR signaling actively blocks the formation of TMPs responding to weak TCR agonists, thereby promoting the accumulation of high-affinity T cells finally dominating the TM pool.