Fig. 1

Development and subgroups of NK cells. In bone marrow, NK cells develop from hematopoietic stem cells (HSCs) through common lymphoid progenitors (CLPs) and NK cell precursors (NKPs), and then migrate to peripheral blood (cNK cells) or tissue (trNK cells). The differentiation of trNK-cells occurs in distinct tissue sites, including the lung, thymus, liver, uterus, skin, subcutaneous adipose tissue, and kidney. In these sites, NK cells have different phenotypic features and functions, which constitute the circulation of NK cells at different stages of maturation. CLA, cutaneous lymphocyte-associated antigen; CCR8, C-C motif chemokine receptor 8; GATA3, GATA binding protein 3; CXCR6, C-X-C motif chemokine receptor 6; KIR, killer cell immunoglobulin-like receptor; CILCP, common innate-like cell precursor