| Ascending thoracic aortic conduits were freshly harvested from Chinese Experimental Swine (CES) in a sterile fashion. Within two hours, they were decellularized by TritonX-100 solely or combined with one of the following methods including 90KW Untrasonic wave, 135KW ultrasonic wave, 180KW ultrasonic wave, as well as SDS. The untreated fresh aortic conduit served as control preserved in PBS including antibiotics mentioned above without any treatment. Acellular group through ultrasound wave with 90 KW and TritonX-100, In the first stage, arteries are placed in a buffer containing 1%TritonX-100, under continuous shaking for 1h at 4°C. In the second stage, arteries are placed in Ultrasonic Processors for five minutes, with the ultrasonic power is 90KW. Then, decellularised arteries are extensively washed with and incubated in PBS for 1 h. Acellular group through ultrasound wave with 180 KW and TritonX-100, with the ultrasonic power is 180KW, others is as same as group two. Acellular group through ultrasound wave with 270 KW and TritonX-100, with the ultrasonic power is 180KW, others is as same as group two. Acellular group through TritonX-100, arteries are placed in a buffer containing 1%TritonX-100, under continuous shaking for 176h. Acellular group through SDS(Sodium dodecyl sulfate)and TritonX-100, arteries are placed in a buffer containing 1%TritonX-100, under continuous shaking for 48h, then arteries are placed in a buffer containing 0.1%SDS, under continuous shaking for 48h. The histopathology and microstructure of these processed aortic tissues were studied with light microscope and scanning electronic microscope, to inspect whether endothelial and fibroblast cells (stained by hematoxylin to a bluish-purple color or DAPI) are taken off thoroughly , collagen fibers (stained by eosin to a pink color) and the structure of ECM under endomembrane are intact. As biomarkers of extracellular matrix, laminin and fibronectin on the processed tissue specimen were stained with immunohistochemical methods to inspect whether conservation of Ln or Fn is similar with group one. In addition, the biomechanic properties of tissue specimen in each group were studied and compared to inspect whether mechanics performance of tissue specime is imilar with group one. Heat shrinkage properties of tissue specimen in each group were studied and compared to inspect whether collagen of acellular artery scaffolds abnormally cross link.Results:There are large of ianthinus endothelial and interstitial nucleus and normally intact collagen fibers and cancellated structure in HE staining of fresh arteries. There are not any cells of samples stained by hematoxylin to a bluish-purple color or DAPI while ultrasonic power reach 135KW in group three, indicating that cells were removed from the endomembrane of arterial scaffolds. In the scanning electron microscopy examination of fresh arteries endomembrane, endothelial cells is intensively arrayed with normal intact structure. There is no any cells and its fragments in the endomembrane of group three when the power is 135 KW, the structure of ECM under endomembrane is clear and intact without any destruction, collagen fibers is clear without any disruption. In the immunohistochemistry staining of arterial scaffolds endomembrane, buffy is the masculine sign of Ln and Fn. When ultrasonic power is 135KW, conservation of Ln or Fn is similar with group one. The differences of mechanics performance and heat shrinkage temperature between group three and group one do not have statistical significance. When combined with TritonX-100, ultrasonic wave can thoroughly decellularize the aortic scaffolds. Furthermore, the tissue structure and biomechanic properties can be maximally maintained. In addition, laminin and fibronectin are more abundant in the groups treated with triotnX-100 combined with ultrasonic wave than the traditional chemical decellularization methods (SDS plus TritonX-100).Conclusion:Combination of TritonX-100 and ultrasonic wave is a superior method in processing ATAS.
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