IL-17Promotes Peribronchial Neovascularization In A Murine Model Of Prolonged OVA-challenge

Neovascularization, including angiogenesis and vasculogenesis, has been recognized as a crucial event during airway remodeling in asthma. Here,we set out to determine whether IL-17were implicated in this process.We found that prolonged allergen challenge induced a progressive increase in the number of vessels around the airways compared with PBS control (p<0.001),which was positively correlated with level of IL-17in BALF. Furthermore, increase in the density of bronchial vessels also can be abrogated by anti-IL-17antibody administration. In addition, IL-17had no direct effect on the proliferation of pulmonary microvascular endothelial cells(PMVECs),whereas markedly promoted PMVECs tube formation in matrigel in a concentration-dependent manner in vitro. We also showed that IL-17was chemotactic for endothelial progenitor cells at concentration ranging from lng/ml to100ng/ml in vitro.To sum up, we describe here that IL-17may mediate the recruitment of endothelial progenitor cells and angiogenesis of PMVEC, which might contribute to peribronchial neovascularization during airway remodeling in asthma.