Abstract
INTRODUCTION: Allergic asthma is a chronic inflammatory airway disease driven by the cytokine interleukin-13 (IL-13). Although IL-13 signals through the canonical JAK1/TYK2/STAT6 pathway, our understanding of the totality of IL-13-induced signaling intermediates is incomplete. METHODS: To address this, we performed a phospho-proteomic analysis of IL-13-stimulated A549 human airway epithelial cells. IL-13 stimulation led to differential phosphorylation at 145 unique serine/threonine residues across 92 proteins involved in diverse cellular processes. In silico analysis was used to predict kinases responsible for the observed changes, and therapeutics which may reduce IL-13-mediated pathology. The activation of these kinases and the ability of these therapeutics to limit IL-13 activity were tested in vitro using molecular techniques and in vivo in an IL-13-induced model of asthma. RESULTS: Analysis of IL-13-induced differentially phosphorylated proteins revealed activation of several pathways including RNA splicing, cytoskeletal remodeling, GTPase activity, and focal adhesion complex formation. Network analysis identified SRC family kinases (SFKs), a family of non-receptor tyrosine kinases, as potential regulators of IL-13-induced changes in phosphorylation, and dasatinib, a pan-SFK inhibitor, as a potential inhibitor of IL-13 signaling. In both human and mouse lung fibroblasts, molecular approaches demonstrated activation of SFKs following IL-13 stimulation. In vitro, dasatinib reduced IL-13-induced STAT6 phosphorylation and downstream gene expression. In vivo, dasatinib attenuated IL-13-induced airway hyperresponsiveness without significantly affecting inflammatory cell infiltration or gene expression in bronchoalveolar lavage fluid. CONCLUSION: These findings support a potential therapeutic role for dasatinib in inhibition of IL-13-driven responses such as those observed in allergic asthma.