Single-cell RNA-seq analysis of IL33 and TSLP expression in human lungs and gating strategy for analysis of mouse lung epithelial cells by flow cytometry. (A and B) Single-cell RNA-seq analysis of IL33 and TSLP expression in epithelial cells from human healthy (A) and asthmatic (B) lungs. t-SNE plots show clustering of 26,154 epithelial cells in upper and lower airways and lung parenchyma in healthy lungs (A; 17 human samples: 6 alveoli and parenchyma, 9 bronchi, 2 nasal), and 25,146 epithelial cells from lower airways in healthy and asthmatic lungs (B; 12 human samples: 15,033 cells from 6 asthma bronchi; 10,113 cells from 6 control bronchi). t-SNE plots were extracted from data obtained by the human lung single-cell atlas (Vieira Braga et al., 2019), and downloaded from https://asthma.cellgeni.sanger.ac.uk. (C) Gating strategy of Epcam+ epithelial cells and CD31+ endothelial cells in the lung of a naïve WT mouse. (D and E) Immunohistofluorescence staining of lung tissue sections (naïve wild type C57BL/6J mouse, steady state) with two distinct rat IgG1 isotype controls (rat IgG1 clone eBRG1, D, red; rat IgG1 clone RB40.34, E, red) for the anti-TL1A antibody (rat IgG1, MAB7441, clone 293327). Double staining was performed with antibodies against RAGE (D, green) or IL-33 (E, green). Images are representative of two independent experiments. Scale bar, 10 μm.