A model system to assess key vascular responses to biomaterials.
OBJECTIVE
To establish a reproducible laboratory test to evaluate prospective vascular biomaterials with respect to their thromboinflammatory properties by examining fibrinogen, platelet, and monocyte binding. Endothelial migration onto these surfaces was used as an index of vascular healing.


METHODS
To evaluate biomaterials for potential thrombogenicity and inflammation, binding assays of radiolabeled human fibrinogen, platelets, and monocytes were performed on standard pieces of vascular biomaterials, including metals and polymeric and ceramic-coated materials. Using an established in vitro endothelial cell migration model, the relative migration rate of cultured human aortic endothelial cells onto these vascular biomaterials was measured and compared. The fibrinogen, platelet, and monocyte binding results were combined along with the migration results to create an overall score of biocompatibility.


RESULTS
A significant direct relation of platelet and monocyte binding to the amount of adsorbed fibrinogen was observed. In contrast, migration rates of cultured human aortic endothelial cells onto the same biomaterial surfaces were found to be inversely related the amount of bound fibrinogen. Among the materials tested, stainless steel received the highest score of biocompatibility, while turbostratic carbon scored the lowest.


CONCLUSIONS
Fibrinogen, platelet, and monocyte binding levels, as well as endothelial migration rates onto vascular material surfaces, provide a basis for evaluating thrombogenicity, inflammatory potential, and endothelialization in the laboratory prior to in vivo testing.
Sprague
Eugene A
EA
Department of Radiology, The University of Texas Health Science Center at San Antonio, Texas 78229, USA. sprague@uthscsa.edu
Palmaz
Julio C
JC
D000497:Alloys / Q000378:metabolism / Q000494:pharmacology; D001011:Aorta / Q000166:cytology / Q000187:drug effects; D001667:Binding, Competitive / Q000187:drug effects; D001672:Biocompatible Materials / Q000378:metabolism / Q000494:pharmacology*; D001792:Blood Platelets / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002858:Chromium Alloys / Q000378:metabolism / Q000494:pharmacology; D003035:Cobalt / Q000378:metabolism / Q000494:pharmacology; D042783:Endothelial Cells / Q000187:drug effects; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects*; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D008422:Materials Testing / Q000379:methods / Q000592:standards; D009000:Monocytes / Q000378:metabolism; D011102:Polyhydroxyethyl Methacrylate / Q000378:metabolism / Q000494:pharmacology; D011138:Polytetrafluoroethylene / Q000378:metabolism / Q000494:pharmacology; D011140:Polyurethanes / Q000378:metabolism / Q000494:pharmacology; D015203:Reproducibility of Results; D013927:Thrombosis / Q000378:metabolism / Q000503:physiopathology
D000497:Alloys; D001672:Biocompatible Materials; D002858:Chromium Alloys; D011140:Polyurethanes; C094863:corethane 80A; C112499:phynox; D011102:Polyhydroxyethyl Methacrylate; C013616:nitinol; D003035:Cobalt; D005340:Fibrinogen; D011138:Polytetrafluoroethylene