| First Author | Renkema KR | Year | 2020 |
| Journal | J Immunol | Volume | 205 |
| Issue | 4 | Pages | 1059-1069 |
| PubMed ID | 32611727 | Mgi Jnum | J:300679 |
| Mgi Id | MGI:6502376 | Doi | 10.4049/jimmunol.1901512 |
| Citation | Renkema KR, et al. (2020) KLRG1(+) Memory CD8 T Cells Combine Properties of Short-Lived Effectors and Long-Lived Memory. J Immunol 205(4):1059-1069 |
| abstractText | CD8 effector T cells with a CD127(hi) KLRG1(-) phenotype are considered precursors to the long-lived memory pool, whereas KLRG1(+)CD127(low) cells are viewed as short-lived effectors. Nevertheless, we and others have shown that a KLRG1(+)CD127(low) 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(+)CD127(low) 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. |
