Biomechanical characterization of decellularized and cross-linked bovine pericardium.
OBJECTIVE
Although bovine pericardium has been used extensively in cardiothoracic surgery, its degeneration and calcification are important limiting factors in the continued use of this material. The study aims were to decellularize bovine pericardium and to compare the biomechanical properties of fresh and decellularized bovine pericardia to those treated with different concentrations of glutaraldehyde (GA).


METHODS
An established protocol for decellularization using sodium dodecyl sulfate was used, and histological analysis performed to validate the adequacy of decellularization. Contact cytotoxicity was used to study the in-vitro biocompatibility of variously treated pericardia. Mechanical testing involved uniaxial testing to failure. Mechanical properties of the fresh and decellularized pericardia (untreated and treated with 0.5% and 0.05% GA) were compared.


RESULTS
Histological analysis of decellularized bovine pericardium did not show any remaining cells or cell fragments. The histoarchitecture of the collagen-elastin matrix appeared well preserved. Untreated decellularized pericardium was biocompatible in contact cytotoxicity tests with smooth muscle and fibroblast cells. The GA-treated tissue was cytotoxic. There were no significant differences in the mechanical properties of fresh and decellularized pericardia, but there was an overall tendency for GA-treated pericardia to be stiffer than their untreated counterparts.


CONCLUSIONS
An acellular matrix, cross-linked with a reduced concentration of GA, can be produced using bovine pericardium. This biomaterial has excellent biomechanical properties and, potentially, may be used in the manufacture of heart valves and pericardial patches for clinical application.
Oswal
Dilip
D
Institute of Medical and Biological Engineering, University of Leeds, Leeds, United Kingdom. diliposwal@hotmail.com
Korossis
Sotirios
S
Mirsadraee
Saeed
S
Wilcox
Hilox
H
Watterson
Kevin
K
Fisher
John
J
Ingham
Eileen
E
D000704:Analysis of Variance; D000818:Animals; D001696:Biomechanical Phenomena; D002417:Cattle; D003094:Collagen / Q000187:drug effects; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004549:Elastin / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects; D005976:Glutaral / Q000494:pharmacology*; D006801:Humans; D008422:Materials Testing; D023421:Models, Animal; D032389:Myocytes, Smooth Muscle / Q000187:drug effects; D010496:Pericardium / Q000166:cytology* / Q000187:drug effects* / Q000648:ultrastructure; D012867:Skin / Q000166:cytology; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D013501:Surface-Active Agents / Q000494:pharmacology; D013552:Swine; D023822:Tissue Engineering; D014021:Tissue Preservation
D003432:Cross-Linking Reagents; D013501:Surface-Active Agents; D012967:Sodium Dodecyl Sulfate; D003094:Collagen; D004549:Elastin; D005976:Glutaral