title: Evaluation of hemocompatibility and endothelialization of hybrid poly(vinyl alcohol) (PVA)/gelatin polymer films.
abstract: Engineered grafts are still needed for small diameter blood vessels reconstruction. Ideal materials would prevent thrombosis and intimal hyperplasia by displaying hemocompatibility and mechanical properties close to those of native vessels. In this study, poly(vinyl alcohol) (PVA)/gelatin blends were investigated as a potential vascular support scaffold. We modified a chemically crosslinked PVA hydrogel by incorporation of gelatin to improve endothelial cell attachment with a single-step method. A series of crosslinked PVA/gelatin films with specific ratios set at 100:0, 99:1, 95:5, and 90:10 (w/w) were prepared and their mechanical properties were examined by uniaxial tensile testing. Tubes, obtained from sutured films, were found highly compliant (3.1-4.6%) and exhibited sufficient mechanical strength to sustain hemodynamic strains. PVA-based hydrogels maintained low level of platelet adhesion and low thrombogenic potential. Endothelial cell adhesion and proliferation were drastically improved on PVA/gelatin films with a feed gelatin content as low as 1% (w/w), leading to the formation of a confluent endothelium. Hydrogels with higher gelatin content did not sustain complete endothelialization because of modifications of the film surface, including phase segregation and formation of microdomains. Thus, PVA/gelatin (99:1, w/w) hydrogels appear as promising materials for the design of endothelialized vascular materials with long-term patency.
authors.affiliation: Inserm, U698, Cardiovascular Bio-Engineering, X. Bichat Hospital, 75018, Paris, France; Institut Galilée, University Paris 13, 93430, Villetaneuse, France.
authors.forename: Julia M
authors.initials: JM
authors.lastname: Ino
authors.forename: Ervi
authors.initials: E
authors.lastname: Sju
authors.forename: Véronique
authors.initials: V
authors.lastname: Ollivier
authors.forename: Evelyn K F
authors.initials: EK
authors.lastname: Yim
authors.forename: Didier
authors.initials: D
authors.lastname: Letourneur
authors.forename: Catherine
authors.initials: C
authors.lastname: Le Visage
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D001807:Blood Vessel Prosthesis; D002448:Cell Adhesion; D049109:Cell Proliferation; D042783:Endothelial Cells / Q000166:cytology*; D004730:Endothelium, Vascular / Q000166:cytology; D005780:Gelatin / Q000737:chemistry*; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D008422:Materials Testing; D010949:Plasma / Q000378:metabolism; D010973:Platelet Adhesiveness; D011108:Polymers / Q000737:chemistry*; D011142:Polyvinyl Alcohol / Q000737:chemistry*; D012995:Solubility; D013314:Stress, Mechanical; D013499:Surface Properties; D013917:Thrombin / Q000096:biosynthesis
chemical_list: D001672:Biocompatible Materials; D020100:Hydrogels; D011108:Polymers; D005780:Gelatin; D011142:Polyvinyl Alcohol; D013917:Thrombin
keywords: endothelial cells; mechanical properties; platelet adhesion; surface modification; vascular grafts