IL-33 regulated expression of cell surface molecules on lung ILC2. Naïve lung ILC2 were pretreated and stimulated as in Fig. 2 (C). The cells were stained with fluorescent-labeled antibodies and then analyzed for expression of CD127, CD25, c-Kit, Sca-1, and ST2L on the CD45.2+Lineage- population by flow cytometry. The solid-lined, gray-filled, and black-filled histograms represent unstained, isotype antibody-stained, and specific antibody-stained cells, respectively. Results are representative of three independent experiments.