PECAM1 and pulmonary emphysema: Stolk et al. (2016) [50] demonstrated that autologous administration of BM-MSCs before and after LVRS for severe emphysema patients is feasible and safe; increased CD31 expression indicates that the BM-MSC treatment may stimulate microvascular endothelial cells in the most severely affected parts of the lung and may therefore be a promising treatment for emphysema.