The nature of inner cellular lining of the expanded polytetrafluoroethylene vascular graft: immunohistochemical study.

Histological and immunohistochemical studies of the healing processes of expanded polytetrafluoroethylene (PTFE) vascular graft were performed. In the animal experiment, endothelial cell lining, confirmed by immunohistochemical staining for anti-Factor VIII related antigen, existed nearly over all of the pannus. The endothelial cells also formed to some extent over the graft without pannus. Endothelialization showed a close dependency on the surface condition of the underlying tissue rather than on a time factor. In the human experiment, an endothelial island was observed in the middle portion of the graft in one case, supporting the hypothesis of the blood stream origin of endothelial cells.