Sequential bone marrow-cell delivery of VEGFA/S1P improves vascularization and limits adverse cardiac remodeling after myocardial infarction in mice.

Microvascular dysfunction and resulting tissue hypoxia is a major contributor to the pathogenesis and evolution of cardiovascular diseases (CVD). Diverse gene and cell therapies have been proposed to preserve the microvasculature or boost angiogenesis in CVD with moderate benefit. In this study, we tested in vivo the impact of sequential delivery by bone marrow cells of the pro-angiogenic factors vascular endothelial growth factor (VEGFA) and sphingosine-1-phosphate (S1P) in a myocardial infarction model. For that we transduced mouse bone marrow cells with lentiviral vectors coding for VEGFA or sphingosine kinase (SPHK1), which catalyzes S1P production, and injected them intravenously 4 and 7 days after cardiac ischemia/reperfusion in mice. Sequential delivery by transduced BM cells of VEGFA and S1P led to increased endothelial cell numbers and shorter extravascular distances in the infarct zone which support better oxygen diffusion 28 days post-MI as shown by automated 3D image analysis of the microvasculature. Milder effects were observed in the remote zone together with increased proportion of capillaries. BM cells delivering VEGFA and S1P also decreased myofibroblast abundance and restricted adverse cardiac remodeling without major impact on cardiac contractility. Our results indicate that BM cells engineered to sequentially deliver VEGFA/S1P angiogenic factors may constitute a promising strategy to improve micro-vascularization and oxygen diffusion thus limiting the adverse consequences of cardiac ischemia.