KLRG1+ Memory CD8 T Cells Combine Properties of Short-Lived Effectors and Long-Lived Memory.
Kristin R RenkemaMatthew A HugginsHenrique Borges da SilvaTodd P KnutsonChristine M HenzlerSara E HamiltonPublished in: Journal of immunology (Baltimore, Md. : 1950) (2020)
CD8 effector T cells with a CD127hi KLRG1- phenotype are considered precursors to the long-lived memory pool, whereas KLRG1+CD127low cells are viewed as short-lived effectors. Nevertheless, we and others have shown that a KLRG1+CD127low population persists into the memory phase and that these T cells (termed long-lived effector cells [LLEC]) display robust protective function during acute rechallenge with bacteria or viruses. Whether these T cells represent a true memory population or are instead a remnant effector cell population that failed to undergo initial contraction has remained unclear. In this study, we show that LLEC from mice express a distinct phenotypic and transcriptional signature that shares characteristics of both early effectors and long-lived memory cells. We also find that in contrast to KLRG1+ effector cells, LLEC undergo homeostatic proliferation and are not critically dependent on IL-15 for their maintenance. Furthermore, we find that LLEC are predominantly derived from KLRG1+ effector cells when isolated at day 12 of the response. Our work challenges the concept that the KLRG1+CD127low population is dominated by short-lived cells and shows that KLRG1 downregulation is not a prerequisite to become a long-lived protective memory T cell.
Keyphrases
- induced apoptosis
- cell cycle arrest
- signaling pathway
- working memory
- dendritic cells
- regulatory t cells
- type diabetes
- type iii
- gene expression
- stem cells
- cell death
- metabolic syndrome
- immune response
- bone marrow
- liver failure
- heat shock protein
- hepatitis b virus
- nk cells
- insulin resistance
- heat shock
- african american
- smooth muscle