Effect Of Composite Islet-endothelial Cell Grafts To Instant Blood Mediated Inflammatory Reaction In Islet Transplantation On The Rat

PrefaceAlthough islet transplantation are good prospects for development,it is still faced with the need for pancreatic mass,a lower survival rate,recurrence of autoimmune diseases caused by graft failure and so on.In clinical islet transplantation through portal vein,the substantial islet loss after transplantation is one of the main problem.At transplantation,the portal vein injection of insulin and blood contact,the occurrence of a coagulation/inflammatory response process,we call the instant blood mediated inflammatory reaction.(IBMIR) IBMIR are characterized with coagulation and complement system activation,the collection and infiltration of leukocytes and platelets adhesion and activation.Tissue factor is the main initiation factor IBMIR.This experiment is to observe effect of composite islet-endothelial cell grafts to instant blood mediated inflammatory reaction in islet transplantation in rat.Materials and MethodsAnimal:SD rat of either sex with weigh ranging from 250-300g as the donor, provided by animal center of China medical university.Purified islets are obtain by perfusion of rat pancreatic digestive juice in situ and discontinuous density gradient centrifugation.The endothelial cells are obtained by collagenase digestion method from patch rat aortic,and cultured randomly divided into 8 groups Islet and endothelial cells co-cultured 5 days,accessing to islet coated endothelial cells,that is,composite islet-endothelial cell grafts.In the process of cultivate,we obtain insulin release index with glucose-stimulated test.Coated group,uncoated group and PBS control group were placed in simulated blood circulation system in the reaction tube 3,respectively, before reperfusion,5 minutes,15 minutes,30 minutes,60 minutes of collecting plasma for analysis.TAT,C3a and platelet are measured.Through HE staining and immunohistochemical staining we have a morphological observation.Statistical analysis:all the data expressed in meanlSD.The significant of difference was evaluated by t test or ANOVA.P＜0.05 was considered having statistical significance.ResultsThe plasma TAT,C3a and the number of platelets in uncoated group and the composite islet-endothelial cell grafts group at 60 minutes after reperfusion have a significant difference(P＜0.05).The neutrophil filtration decreased significantly in uncoatedgroup than in composite islet-endothelial cell grafts group from immunohistochemical staining of pancreatic islet tips.Conclusions1.The composite islet-endothelial cell grafts does not effect the function of islet.2.The composite islet-endothelial cell grafts can significantly reduce the initial islet transplantation activation of coagulation,complement activation,platelet consumption and inflammatory cell infiltration,which significantly reduced the response IBMIR.3.The way of composite islet-endothelial cell grafts provides a new method for clinical pancreatic transplantation.