IL4 and asthma: WT mice developed all the cardinal features of asthma, including immune cell infiltration in the bronchoalveolar space, with increased total cells and eosinophils (Figures 2B and 2C), and increased secretion of the epithelial-derived alarmin IL-33 (Figure 2D), of the Th2 cytokines IL-4, IL-5, and IL-13 (Figures 2E–2G) and of the eosinophil-attracting chemokines CCL11 and CCL24 (Figures 2H and 2I).