Phenotypical analysis of early ILC progenitors. (A) Cell surface expression of the indicated protein on ALPs, EILPs, and ILCps from Tcf7^EGFP/+ mice analyzed by flow cytometry. (B) Relative mRNA expression of the indicated molecules quantified by RNA sequencing for ALPs, EILPs, and ILCps. Relative protein expression of the indicated molecules quantified by flow cytometry for ALPs, EILPs, and ILCps from Tcf7^EGFP/+ mice as shown in A. Data are presented as mean of expression. n = 7 for ALPs and EILPs; n = 5 for ILCps and are presented as geometric mean fluorescence intensity minus fluorescence minus one. (C) Flow cytometric analysis of ALPs, TCF-1⁺ EILPs, and TCF-1⁺ ILCps by intracellular staining for the indicated transcription factors. (D) Flow cytometric analysis of ALPs, EILPs, and ILCps. Cell surface expression of Flt3 and IL-7Rα and intracellular staining of PLZF are shown. (E) Flt3 expression on EILPs, and Flt3^low and Flt3^high gating used for the histograms on the right. GFP expression on ILC progenitors from a Tcf7^EGFP/+ mouse. YFP expression on ILC progenitors from an Il7r-Cre R26-stop-YFP Tcf7^EGFP/+ mouse. Flt3^low EILPs and Flt3^high EILPs as gated on the left histogram are compared with ILCps. All data are representative of three independent experiments.