Although this study did not elucidate the mechanism by which HDM allergens stimulated the production of TSLP, IL-25, and IL-33 into the airways, it is tempting to speculate that the initiation of HDM allergy results from three main steps: IL-33 stimulation, OX40L upregulation, and expansion of ILC2s into the airways. The gene discussed is IL33; the disease is allergic disease.