Figure 4.

Bcl11b^−/− ILC2s promote airway infiltration of neutrophils in response to papain, and confer increased protection to C. rodentium. A) Flow cytometry analysis of intracellular IL-13, IL-5, IL-17 and IL-22 in Lin⁻CD90⁺Sca-1⁺CD127⁺ ILC2s from the lungs of papain- or PBS-treated TMX- Bcl11b^F/Fcre-ERT2 (red) and -wild type control mice (black). Gray shaded area represents PBS-treated mice. B) Average frequency of cytokine-producing Lin⁻CD90⁺Sca-1⁺CD127⁺ ILC2s from the lungs of papain-treated TMX-Bcl11b^F/Fcre-ERT2 (black) and -wild type control (white) mice. Data (n=6), derived from two independent experiments, are presented as mean ± SEM. Significance determined by Student's t test, * indicates p-value ≤ 0.05. C) Absolute numbers of Lin⁻CD90⁺Sca-1⁺CD127⁺ ILC2s from the lungs of the indicated groups of mice. D) Absolute numbers of eosinophils (Lymph⁻CD11b⁺CD11c^loLy6G⁻SiglecF⁺) and neutrophils (Lymph⁻CD11b⁺CD11c^loLy6G⁺SiglecF⁻) in the lung and BALF of the indicated groups of mice, determined by flow cytometry analysis. Data (n=6), derived from three independent experiments, are presented as mean ± SEM. Significance determined by Student's t test, * indicates p-value ≤ 0.05. E) Mucus production evaluated by Periodic Acid Schiff (PAS) staining of lung tissues of papain-treated TMX- Bcl11b^F/Fcre-ERT2 and -wild type control mice. Data is representative of three independent pairs. Scale bar - 200 µm. F) Bacterial colony forming units (CFU) from feces of Citrobacter-infected TMX-Rag1^−/− Bcl11b^F/Fcre-ERT2 (black) and -Rag1^−/− mice (white) day 5 post-infection. Data (n=4), derived from two independent experiments, are presented as mean ± SEM. Significance determined by Student's t test; * indicates p-value ≤ 0.05. G–H) Flow cytometry analysis of intracellular IL-17 vs. IL-22 in mILC2s and ILC3s from the mLNs (G) and SILP (H) of Citrobacter-infected TMX-Rag1^−/−Bcl11b^F/Fcre-ERT2 and -Rag1^−/− mice day 5 post-infection. Data (n=4) is derived from two independent experiments.