Human CD8<sup>+</sup> T-Cell Populations That Express Natural Killer Receptors
June‐Young Koh, Dong-Uk Kim, Bae-Hyeon Moon, Eui‐Cheol Shin
Abstract
CD8 + T cells are activated by TCRs that recognize specific cognate Ags, while NK-cell activation is regulated by a balance between signals from germline-encoded activating and inhibitory NK receptors.Through these different processes of Ag recognition, CD8 + T cells and NK cells play distinct roles as adaptive and innate immune cells, respectively.However, some human CD8 + T cells have been found to express activating or inhibitory NK receptors.CD8 + T-cell populations expressing NK receptors straddle the innate-adaptive boundary with their innate-like features.Recent breakthrough technical advances in multi-omics analysis have enabled elucidation of the unique immunologic characteristics of these populations.However, studies have not yet fully clarified the heterogeneity and immunological characteristics of each CD8 + T-cell population expressing NK receptors.Here we aimed to review the current knowledge of various CD8 + T-cell populations expressing NK receptors, and to pave the way for delineating the landscape and identifying the various roles of these T-cell populations.