IL-25–elicited MPP^type2 cells possess a unique transcriptional profile from ILC2 cells. (a and b) C57BL/6 WT mice (The Jackson Laboratory) were treated with 0.3 µg of recombinant IL-25 daily for 7 d. MLNs and PECs were harvested from IL-25–treated mice and MPP^type2 cells (Lin^neg T1/ST2^neg IL-7Rα^neg CD4^neg CD90^neg CD25^neg c-kit^pos; a) were FACS purified to ≥95% purity (b). Three biological replicates of MPP^type2 cells were collected, and mRNA was isolated, amplified, and hybridized to Affymetrix gene chips for microarray analysis. The previously published microarray gene expression profile of lung-resident ILC2 was used for comparison (GEO series no. GSE46468; Monticelli et al., 2011). (c) Heat map representing gene expression profiles of the top 100 differentially expressed genes between MPP^type2 cells and ILC2. Red indicates high expression, and blue indicates low expression. (d) GSEA comparing the gene expression signatures of MPP^type2 cells and ILC2. (e) List of leading edge genes from GSEA analysis from d. (f) PCA plot comparing transcriptional profiles for MPP^type2 cells (1), ex vivo nuocytes (2; GSE25890), NHCs (3; GSE18752), lung-resident ILC2 (4; GSE46468), unstimulated lung NHCs (5; GSE36057), splenic LTi cells (6, GSE46468; and 7, GSE18752), and BM-GMPs (8). Categories of ILC2 (green shaded area), ILC3 (red shaded area), and progenitors (blue shaded area) were grouped (as indicated in f, dashed lines), and Euclidean distance measurements between MPP^type2 cells and BM-GMP versus ILC2 or ILC3 were calculated (g). ***, P < 0.0001. MPP^type2 cells versus BM-GMP versus ILC2, P = 8.5 × 10⁻⁸; MPP^type2 cells versus BM-GMP versus ILC3s, P = 3.1 × 10⁻⁶.