Background: This study aims to investigate whether an endothelial marker ephrin-B2 exists in pericardial patches during post-angioplasty repair and whether CD34⁺ endothelial progenitor cells are present in the patches after being implanted into the arterial environment.

Methods: Eighteen eight-week-old male Wistar rats were subjected to laparotomy to check the abdominal aorta below renal arteries, to incise it, and then to perform angioplasty by using porcine or bovine pericardial patch. The control group consisted of 18 age- and weight-matched Wistar rats. Angioplasty was conducted by subcutaneously implanting patches in the control group. The patches were taken on one, three, five, and 30 days after surgery and investigated by histological and immunohistochemical assays, immunofluorescent labeling, Western blotting and reverse transcription polymerase chain reaction.

Results: The patches containing collagen were acellular before angioplasty. After implantation of a bovine pericardial patch, the numbers of ephrin-B2⁺ and CD34⁺ cells increased significantly; however, the test results for CD68, alphaactin and von Willebrand factor were negative. There was a monolayer of cells in the inner luminal surface five days after implantation of a porcine pericardial patch. In contrast, ephrin-B2⁺ or CD34⁺ cells did not appear in the control group. On the postoperative 30th day, there were ephrin-B2⁺ and CD34⁺ cells in the two types of patches.

Conclusion: Ephrin-B2⁺ and CD34⁺ cells began to infiltrate pericardial patches soon after implantation. The patches which allow endothelialization during arterial remodeling are potentially applicable to tissue plasty and angioplasty.

Keywords : Angioplasty; CD34; ephrin-B2; pericardial patch; positive cell; repair material