A study investigating post-infarction contractile function of the heart via 2D echocardiography, significantly impaired LV function was improved by 3% after EPCs infected with stromal-cell derived factor-1α (SDF-1α) were transplanted; SDF-1α promoted the proliferation and migration of the EPCs into injured tissue [36]. The gene discussed is CXCL12; the disease is infarction.