Bone Marrow–derived Endothelial Progenitor Cells Promote Hematopoietic Reconstitution After Hematopoietic Stem Cell Transplantation

ObjectiveA hematopoietic deficit is a serious complication after hematopoietic stem cell transplantation. It has been shown that fetal blood–derived endothelial progenitor cells (EPCs) can promote hematopoietic reconstitution after transplantation. This study investigated whether EPCs from bone marrow (BM) of adult mice could promote hematopoietic reconstitution.MethodsLethally irradiated BALB/c mice were administered BM cells or BM cells plus EPCs.ResultsThe results showed that EPC-treated mice displayed accelerated recovery of peripheral blood white blood cells and reticulocytes. But the platelets were not significantly different with versus without EPCs. Accelerated recovery of BM sinusoidal vessels, promotion of stem cell implantation, and decreased adipocyte formation were associated with the mechanism. Systemic administration of anti-vascular endothelial cadherin antibody neutralized these effects significantly.ConclusionThese data showed that BM-derived EPC infusions augmented hematopoiesis suggesting a new approach to promote hematopoiesis.