Sci Adv. 2025 Aug 8;11(32):eadv9650. doi: 10.1126/sciadv.adv9650. Epub 2025 Aug 8.
ABSTRACT
KIR+NKG2A– natural killer (NK) cells have the unique ability to detect down-regulation of single HLA-I allotypes, frequently occurring in malignantly transformed and virus-infected cells. We have recently shown that circulating innate lymphoid cells 1 (cILC1s) have the potential to generate such KIR+NKG2A– NK cells, but their developmental origin was unknown. Here, we demonstrate that the development of cILC1 is thymus dependent and identify a putative progenitor of cILC1s in the thymus (thyILC1). Single-cell RNA sequencing analysis revealed a close relationship of thyILC1s to CD34+ double-negative thymocytes. Both generated comparable NK cell frequencies, while only thyILC1s could be efficiently differentiated into KIR+NKG2A– NK cells. Last, patients with FOXN1 haploinsufficiency, showing congenital thymic hypoplasia, exhibited a profound deficiency of cILC1s but not cILC2s and cILC3s, demonstrating their specific thymus dependency. Together, the data suggest that thyILC1s are the source of a thymus-dependent NK cell differentiation pathway that promotes generation of KIR+NKG2A– NK cells.
PMID:40779632 | DOI:10.1126/sciadv.adv9650
