NGF and asthma: Eosinophils produce a variety of asthma-inducing factors including major basic protein (MBP), eosinophilic peroxidase (EPO), eosinophil cationic protein (ECP), leukotrienes, and remodeling factors, such as transforming growth factor beta (TGF-β), IL-13, matrix metalloproteinase (MMP), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and nerve growth factor (NGF).9