A. Experimental protocol showing the animal groups (WT and Rag1-/-), the corresponding treatment regimen and timeline. B. C57B6/J WT mice were treated with PBS, Poly(I:C), IL-33 or IL-33+Poly(I:C). Lung single cell suspensions were prepared and the percentage and number of ILC2 cells in lungs were analyzed. In addition, lung cells were stimulated with PMA in cultures as described in the Materials and Methods. The percentage of IL5+/IL13+-double positive ILC2 cells in lungs were analyzed. (n = 3–5 per group as indicated with open circles). C. Similar to B, instead of IL-33, A. flavus was used. (n = 2–5). D. Similar to B, instead of WT mice, the Rag1-/- mice were used. (n = 2–5 per group as indicated with open circles). E. C57B6/J WT mice were treated with PBS, Poly(I:C), IL-33 or IL-33+Poly(I:C). The lung ILC2 cells were analyzed with Ki-67 staining and isotype antibody. The result is a representative of three independent experiments.