ILCPs are found in neonatal mouse lungs. (A) Lin⁻Thy1⁺CD127⁺ cells from neonatal (12-d-old) lung, adult, and neonatal (12-d-old) BM from Tcf7^EGFP mice were sequentially gated and divided into Tcf7^EGFP+ST2⁻ (green) and Tcf7^EGFP−ST2⁺ (black) subsets and analyzed for the expression of IL-18Rα and Kit. (B) BM ILCPs defined by Lin⁻Thy1⁺CD127⁺Tcf7^EGFP+ST2⁻ (IL-18Rα⁺Kit⁺) and lung ILCPs defined by Lin⁻Thy1⁺CD127⁺Tcf7^EGFP+ST2⁻IL-18Rα⁺Kit⁺ were cultured on OP9 with IL-7 and SCF for 1 wk. The progenies were analyzed for ICOS and NK1.1 expression, and the frequencies of the indicated subsets are shown in pie charts. Data in A are representative of two independent experiments with two or more mice per group in each experiment, and data in B are representative of three replicates per experimental group in one experiment.