Autocrine angiogenic vascular prosthesis with bone marrow transplantation

Abstract

Synthetic vascular prostheses are foreign bodies, so that blood coagulation can occur on their luminal surfaces, causing graft occlusion very frequently in prostheses of small diameter. A vascular prosthesis needs angiogenesis for endothelialization of the luminal surface, as endothelial cells have natural and permanent antithrombogenic properties. To induce capillary growth into the graft, we developed a method of transplanting bone marrow cells, which are primitive, strong enough to survive, and create blood cells, resulting in the inducement of capillary growth. In an animal experiment, marrow cells were infiltrated into the walls of long-fibril expanded polytetrafluoroethylene (ePTFE) vascular grafts. The grafts were implanted in the abdominal aortic position of 24 dogs autologously. Marrow cells survived and continued exogenous hemopoiesis for up to six months and were immunohistochemically reactive to basic fibroblast growth factor (bFGF). All the grafts older than three weeks had complete endothelialization and maintained their patency. Twenty grafts without bone marrow were implanted as controls. Endothelialization was present at anastomotic sites, but other areas were covered with fresh thrombi. Four out of seven control grafts were patent with endothelial cell lining at six months, but three were occluded and one of the four grafts was still covered with a thrombus layer. Bone marrow with its unique native properties produced autocrine angiogenicity in the graft.