Combining pharmacological mobilization with intramyocardial delivery of bone marrow cells over-expressing VEGF is more effective for cardiac repair

We postulated that combining cell based hVEGF165 gene delivery with cytokine-induced mobilization of bone marrow cells (BMC) may give better prognosis in an infarcted heart. Forty-eight myoabalated female C57BL/6J mice (20–25 g) received 1 × 106 BMC from transgenic GFP+ male mice. One month later, acute myocardial infarction (MI) model was developed by coronary artery ligation. Animals were grouped (N = 12) to receive intramyocardial injections of 10 μl DMEM without cells (group 1; group 2) or with 1 × 105 mesenchymal stem cells (MSC) over-expressing hVEGF165 (group 3; group 4). The animals received either cytokine therapy (group 2 and 4) or saline solution (group 1 and 3) for 7 days after MI. Hemodynamic data were obtained 4 weeks after MI using Millar's P–V system and cardiac tissue was harvested for immunohistological studies. We observed regeneration and extensive survival of BMC in and around the infarcted myocardium in groups 3 and 4. Blood vessel density was markedly enhanced in group 4 as compared with groups 1 and 2 in peri-infarct area. Fibrotic area was significantly reduced with improved LV-contractile function in group 2 and 4. LV-systolic and diastolic functions were well-preserved in group 4 as indicated by +dP/dt, –dP/dt and Tau (glantz). We therefore conclude that transplantation of MSC overexpressing VEGF combined with cytokine induced BMC mobilization is superior to either of the monotherapy approach for angiomyogenesis and LV-function recovery.