Atopic asthma is associated with increased levels of TH2 cytokines in the airways, including IL-4.55, 56, 57 Several studies demonstrate that IL-4 enhances the capacity of human airway epithelial cells to produce TSLP.58, 59 Moreover, the combination of IL-4 plus double-stranded RNA synergistically enhanced production of TSLP from human airway epithelial cells.58 Here, IL4 is linked to atopic asthma.