IL-25–mediated induction of MPP^type2 cells and type 2 inflammation occurs independently of ILC2. (a–i) C57BL/6 Rag1^−/− mice (The Jackson Laboratory) were treated i.p. with PBS (control) or 0.3 µg of IL-25 plus isotype mAb (Iso.) or anti-CD90 mAb. (a and b) Frequencies (a) and total cell numbers (b) of CD90^pos T1/ST2^pos IL-7Rα^pos ILC2 in the MLNs of control or IL-25–treated mice given either isotype or anti-CD90 mAb. (c and d) Frequencies (c) and total cell numbers (d) of CD90^neg T1/ST2^neg IL-7Rα^neg MPP^type2 cells in the MLNs of control or IL-25–treated mice given either isotype or anti-CD90 mAb. Plots are gated on live, Lin^neg (CD4, CD8, CD11b, CD11c, and CD19) cells or as indicated. (e and f) Quantitative real-time PCR of Il4, Il5, and Il13 gene expression levels from lung (e) or small intestinal tissue (f) of control or IL-25–treated mice receiving either isotype or anti-CD90 mAb. RQ, relative quantification. (g) Periodic acid–Schiff/Alcian blue staining of lung and small intestine (SI) tissue from control or IL-25–treated mice receiving either isotype or anti-CD90 mAb. Bars: (top) 50 µm; (bottom) 100 µm. (h) Goblet cell (GC) counts from g. nd, not detected. (i) Frequency and total cell numbers of eosinophils in the lung from control or IL-25–treated mice given either isotype or anti-CD90 mAb. Frequency is percentage of SSC^hi SiglecF^pos cells gated on live, Lin^neg CD11b^pos cells. Data in a–i are representative of three independent experiments (control + Iso., n = 6; control + anti-CD90, n = 6; IL-25 treated + Iso., n = 6; IL-25 treated + anti-CD90, n = 6). *, P < 0.05; **, P < 0.01. Control ILC2 versus IL-25 + Iso. ILC2, P = 0.057; IL-25 + Iso. ILC2 versus IL-25 + αCD90 ILC2, P = 0.059; IL-25 + Iso. MPP^type2 versus IL-25 + αCD90 MPP^type2, P = 0.41; lung GC#: IL-25 + Iso. versus IL-25 + αCD90, P = 0.10; SI GC#: IL-25 + Iso. versus IL-25 + αCD90, P = 0.16. Error bars indicate SEM.