Mechanism Of Xenogeneic Acellular Arterial Matrix In Repairing Extrahepatic Biliary Defects And Benign Stenosis In Pigs

[Objective]To study the short(2-3 cm),long(4-6 cm)and long-term(12 month s)effects of human xenogeneic acellular artery on the repair of extrahepatic biliary tract defects in small ear pig liver in southern Yunnan,China.To investigate the mechanism of epithelial-mesenchymal transition(EMT)formation during anastomotic scar healing.[Method]The repair effect of human xenogeneic acellular arterial matrix was judged through the establishment of a model of extrahepatic biliary tract defect in small ears of liver in southern Yunnan and the hematological examinations after different lengths of acellular arterial matrix repair.Experimental methods such as HE staining,Masson staining and immunohistochemistry were used to determine the mechanism of cicatrix healing.[Results]The short-segment human xenogeneic acellular arterial matrix can stably repair the extrahepatic biliary tract defect model of small ear in southern Yunnan Province,and hematology shows that the short-segment human xenogeneic acellular matrix can improve the healing effect of anastomosis of bile duct severance injury.The long segment has poor effect in repairing the short segment,and further research is needed.Epithelial-mesenchymal transition occurs when segmental defects of the biliary tract heal.[Conclusion]Human xenogeneic acellular arterial matrix can repair the extrahepatic biliary tract defect of Diannan Xiaoer pig for up to 12 months with epithelial-mesenchymal transition at the repair site,providing a new treatment for clinical repair of biliary tract injury.[Objective]To test the effect of VEGF on the proliferation and migration ability of bile duct epithelial cells;to prepare VEGF-DOPA-acellular arterial matrix and test its applicability as a tissue-engineered bile duct.[Methods]Preparing an acellular matrix by a two-step enzyme digestion method;The effects of VEGF on the migration and proliferation of bile duct epithelial cells were detected by CCK8,Transwell,cell scratch and plate cloning experiments.The human acellular arterial matrix was immersed in 2mg/ml DOPA-Tris-HCL solution to form an o-diphenol group platform,which was modified by VEGF-A;Cytotoxicity of material extracts detected by CCK8;The experimental techniques such as microscopic observation,HE staining,immunofluorescence,Western Blot,and electronic microscope observation were used to detect the adhesion and proliferation characteristics of porcine bile duct epithelial cells on the platform.The ability of material to induce angiogenesis was tested by subcutaneous matrix gel-forming experiment in nude mice.[Results]VEGF can promote the proliferation and migration of bile duct epithelial cells.VEGF-DOPA-acellular arterial matrix is not cytotoxic,has good biocompatibility,can promote the adhesion of bile duct epithelial cells in vitro,can accelerate the re-cellularization process of the acellular arterial matrix,and can promote the directional growth of blood vessels.[Conclusion]VEGF-DOPA-acellular arterial matrix can provide a practical material for tissue-engineered bile duct quickly and is expected to develop into a commercial tissue-engineered bile duct and provide a more optimal solution for the treatment of biliary tract injury,especially extrahepatic biliary tract injury.