In the current study, we showed that allergen-activated eosinophils promoted the gene expression of collagen I, fibronectin, elastin, MMP-12, ADAM33, TGF-β1, TGF-β2, Smad4, and ROCK1 in ASMC, and collagen I, fibronectin, elastin, versican, TIMP-1, TGF-β1, TGF-β2, LTBP3, Smad5, Smad7, and Smad9 in PF. This evidence concerns the gene SMAD4 and pemphigus foliaceus.