Experimental Study of Acellular Bovine Pericardium as Ovine Pulmonary Artery Patch

ObjectiveTo evaluate the feasibility of using acellular bovine pericardium as a viable tissue engineering vascular patch.MethodsFresh bovine pericardium was treated by enzyme detergent cell extraction, then they were used as vascular patches, ovine jugular vein segments were harvested, separated into endothelial and myofibroblast cells, expanded in cell culture, sequentially seeded onto acellular bovine pericardium patches (3cm×3cm). After 7 days of in vitro culture, the autologous cell/patches as experimental group ( n =5) were used to replace partial pulmonary artery wall. Animals were sacrificed at 4, 6, 8, 12 and 24 weeks. The acellular bovine pericardium patches without autologous cells were used as control group ( n =3). Animals were sacrificed at intervals of 4, 12 and 24 weeks. Explanted patches were evaluated by macroscopic and histologic examinations, assayed for calcium, elastin and collagen content.ResultsAll animals were survived without complications of thrombosis and aneurysm before sacrificed; there was no significant difference in calcium content in two groups; elastin ratio assay showed progressive increase over 4 to 24 weeks, similar to normal pulmonary artery wall, suggesting an ongoing tissue remodeling.ConclusionThe acellular bovine pericardium patch with or without autologous cell seeded to a certain extent can be changed into viable vascular wall tissue after being used to replace partial ovine pulmonary artery wall.