However, given that there was an effect of IL13 stimulation on the expression of TRAIL and its receptor, DR5, on nondiseased fibroblasts and the elevated expression of IL13 mRNA in IPF relative to normal lungs [56], targeting IL-13 signaling might help sensitize a subset of lung fibroblasts to the effects of TRAIL in IPF patients. This evidence concerns the gene IL13 and idiopathic pulmonary fibrosis.