HGF and chronic obstructive pulmonary disease: Numerous rodent studies on COPD demonstrated that MSC infusion decrease inflammation and parenchymal damage17 with a number of reports showing MSC paracrine factors including epidermal growth factor, hepatocyte growth factor (HGF),18, 19, 20, 21 vascular endothelial growth factor,17, 22, 23 and keratinocyte growth factor (KGF)24 to be involved (Figure 2, left box).