To examine whether IL-1β may be functionally responsible for the difference between e.c. HDM- and d.c. HDM-induced sensitization and the subsequent asthma, we designed an experimental protocol in which the recombinant mouse IL-1β was supplemented to e.c. HDM treatment on LMP_30μm ears, followed by HDM i.n. challenge (Fig. 3c). The gene discussed is IL1B; the disease is asthma.