PLZF expression maps the early stages of ILC1 lineage development

Diverse populations of group 1 innate lymphocytes, which exert critical early cytolytic functions against virally infected cells, have recently been discovered, raising issues of lineage relationships. We used expression of the transcription factor promyelocytic leukaemia zinc finger (PLZF) to identify the developmental intermediates of innate lymphoid cells type 1 (ILC1s), a subset of innate lymphoid cells that are particularly abundant in the liver, and demonstrated that this lineage arises from a distinct precursor, but that its development partially overlaps with established classical NK stages. Using microarray analysis, we defined a set of PLZF-dependent genes that may contribute to lineage divergence between ILC1s and classical NK cells.