title: Neointimal hyperplasia in allogeneic and autologous venous grafts is not different in nature.
abstract: Neointimal hyperplasia, transplant rejection and thus immunogenicity of allografts are possible reasons for poorer patency rates in cryopreserved venous allografts for peripheral bypass surgery in comparison with autologous venous grafts. To expand the limited knowledge from human allografts, we histologically investigated allogeneic and autologous venous grafts in arterial location. Specimens of allogeneic and autologous venous graft stenosis, harvested 6 months after bypass implantation, were immunohistochemically characterized. Examination of the lesions showed a uniform morphological pattern. A continuous endothelial layer, tissue fibrosis and a thickened neointima with monocytes and dedifferentiated vascular smooth muscle cells were seen in both conduits with very low cell turnover and the absence of acute and chronic inflammation. Neoangiogenesis with CD34-positive endothelium was abundant in the vessel media. The morphological patterns of allogeneic and autologous neointima formation are similar. Consequently, neointimal hyperplasia in venous grafts may reflect a uniform physiological host response of non-immunological factors with the reasons for poorer clinical outcome of cryopreserved allografts yet to be elucidated.
authors: Department for General, Visceral, Vascular and Paediatric Surgery, University Clinic of Würzburg - ZOM, Oberduerrbacher Str 6, 97080, Würzburg, Germany, busch_a2@ukw.de.
authors: Albert
authors: A
authors: Busch
authors: Elena
authors: E
authors: Hartmann
authors: Nicole
authors: N
authors: Wagner
authors: Süleyman
authors: S
authors: Ergün
authors: Ralph
authors: R
authors: Kickuth
authors: Richard
authors: R
authors: Kellersmann
authors: Udo
authors: U
authors: Lorenz
mesh_terms: D064591:Allografts; D064592:Autografts; D015925:Cryopreservation; D004730:Endothelium, Vascular / Q000473:pathology; D006801:Humans; D006965:Hyperplasia; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D058426:Neointima / Q000276:immunology / Q000473:pathology*; D009389:Neovascularization, Pathologic; D012501:Saphenous Vein / Q000637:transplantation*