Objective: To explore whether transplantation of autologous bone marrow stem cells might augment angiogenesis and collateral vessel formation in a canine model of hindlimb ischemia.
Methods: CD34(+) stem cells were centrifugation through Ficoll and an immune magnetic cell sorting system from bone marrow (20 ml) of canine (n = 5) and induced into endothelial cells with VEGF in vitro, and expression of von Willebrand factor. Bilateral hindlimb ischemia was surgically induced in canines and Dil fluorescence labeled autologous stem cells were transplanted into the ischemic tissues.
Results: Four weeks after transplantation, fluorescence microscopy revealed that transplanted cells were incorporated into the capillary network among preserved skeletal myocytes. The stem cells transplanted group had more angiographically detectable collateral vessels, a higher capillary density (12.0 +/- 2.8 vs. 5.0 +/- 1.6 per field; t = 4.17 P < 0.05) and a higher ABI (0.58 +/- 0.14 vs. 0.32 +/- 0.11; t = 2.95, P < 0.05).
Conclusions: Direct local transplantation of autologous bone marrow CD34(+) stem cells seems to be a useful strategy for therapeutic neovascularization in ischemic tissues in adults, consistent with "therapeutic vasculogenesis."