Autologous cell therapy for vascular regeneration: the role of proangiogenic cells

Autologous cell therapy represents a novel treatment option for vascular regeneration in different disease conditions. Both experimental and clinical studies indicate a therapeutic potential for different proangiogenic cells (PCs), including endothelial progenitor cells (EPCs) in the treatment of peripheral artery disease. A significant improvement of ischemic symptoms has been reported in different trials evaluating PCs for the treatment of critical limb ischemia. However, contrasting results from different meta-analyses question the efficacy of PC-based approaches on long-term outcomes, including amputation and survival. Preclinical studies and clinical trials give support to the safety and feasibility of PC therapy in the treatment of ischemic heart disease and heart failure, while evidence indicating a benefit on the reduction of cardiovascular (CV) events is still uncertain. Clinical studies investigating cell therapy in stroke demonstrated controversial results. Despite accumulating experimental results support a therapeutic role for PCs in diabetic retinopathy, data from randomized clinical trials are lacking. Whether PC therapy may limit vascular damage and premature atherosclerosis and reduce CV risk in inflammatory rheumatic diseases needs to be investigated. Despite a number of potential clinical applications of PCs are emerging, there is evidence that CV risk factors and chronic inflammation may induce PC dysfunction, rising possible limitations for the efficacy of autologous PC therapy. Thus, novel strategies aimed at improving PC viability and angiogenic function are warranted in order to improve the efficacy of cell therapy applications.