title: Blood compatibility of human amniotic membrane compared with heparin-coated ePTFE for vascular tissue engineering.
abstract: Amniotic membrane (AM), a placenta-derived natural biomaterial, has several characteristics which make it a potential substitute for blood vessels. However, there are no reports on the effects of the AM on blood components. The aim of this study was to evaluate the blood compatibility of the epithelial and mesenchymal surfaces of the amnion for potential use in vascular tissue engineering. The activation of intrinsic and extrinsic pathways of the clotting system, haemolysis and platelet adhesion were studied and the results were compared with heparin-coated expanded polytetrafluoroethylene (ePTFE) as a standard synthetic vascular graft. Prothrombin time (PT), activated partial thromboplastin time (aPTT), clotting time (CT) and haemolysis (%) tests showed that both the epithelial and mesenchymal sides of the AM are haemocompatible. Platelet aggregation and P-selectin production from the platelets showed that the epithelial surface of the AM has less induction of platelet activation than ePTFE. The results of scanning electron microscopy (SEM) demonstrated that platelets in contact with ePTFE had a higher rate of adhesion than with the epithelial and mesenchymal surfaces of the AM. Moreover, the morphological distribution of the platelets showed that the majority of platelets were round, while a large number of cells on ePTFE were dendritic. These results suggest that the AM which contains epithelial and mesenchymal stem cells has appropriate haemocompatibility to be employed in vascular tissue engineering, especially as a vein substitute. Copyright © 2015 John Wiley & Sons, Ltd.
authors.affiliation: Department of Tissue Engineering, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mona
authors.initials: M
authors.lastname: Kakavand
authors.affiliation: Nanomedicine and Tissue Engineering Research Centre, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Ghasem
authors.initials: G
authors.lastname: Yazdanpanah
authors.affiliation: Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Abolhassan
authors.initials: A
authors.lastname: Ahmadiani
authors.affiliation: Department of Tissue Engineering, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.|Nanomedicine and Tissue Engineering Research Centre, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Niknejad
mesh_terms: D000650:Amnion / Q000737:chemistry*; D001705:Bioprosthesis; D001792:Blood Platelets / Q000378:metabolism; D001807:Blood Vessel Prosthesis; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D005260:Female; D006493:Heparin / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D010974:Platelet Aggregation; D011138:Polytetrafluoroethylene / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D011138:Polytetrafluoroethylene; D006493:Heparin
keywords: amniotic membrane; ePTFE; haemocompatibility; heparin; tissue engineering