| ObjectiveAortic allograft aortic graft replacement open up a new therapeutic approach in the field of heart surgery. In 1966, Ross and Someville succeeded in allograft aortic valve for right ventricular outflow tract reconstruction. But the early clinical effects of allograft aortic valve is unsatisfactory, mainly for the calcification, valvular degeneration, etc.. With the sterilization method and cryopreservation technology, application of the aortic allograft was reemphasized. Compared with artificial biological heart valve and mechanical valve, allograft aortic valve is easy to implant, with less bleeding, small inter-valve pressure gradient, significantly reduced rate of thrombosis, hemolysis. Currently, there is widespread concern on the long-term effect of graft. The currently issues to face are the degradation of homologous aortic graft, calcification and obstruction. Immune rejection of graft in the aorta plays an important role, so the research of allograft rejection in transplant immune rejection reaction not only to identify their mechanism, but also to guide clinical work and to find the appropriate a theoretical basis for the immune rejection. TNF-a as a single nuclear factor, is an important cytokine in the immune inflammatory response, mainly composed of monocytes and macrophages. This study, establishing allogeneic aortic patch graft model, found out the effects of cyclosporin A on allogeneic immune parameters tumor necrosis factor (TNF-a), and pathological grafts change in rat aortic patch after transplantation.Materials and MethodsHealthy Wistar rats were chosen as the receptor 48, SD 20 rats as a donor, and Wistar rats were randomly divided into 3 groups,16 rats in each. Experimental group: the active patch of SD rats cryopreservated in the liquid nitrogen were implanted into Wistar rat abdominal aorta heterotopically. Immune intervention group:the active patch of SD rats cryopreservated in the liquid nitrogen were implanted into Wistar rat abdominal aorta heterotopically, cyclosporine A administration on the first day after transplantation, dose 5mg/kg/day. Control group:sham transplantation group, the abdominal aortic anastomosis after longitudinal incision. Each group were transplanted after 3 days,7 days,14 days,21 days for subjects, four rats were sacrificed in each group per time. Anesthesia on Rats with 10% chloral hydrate solution (2 ml/kg), laparotomy under sterile conditions in the abdominal aorta for blood, which was centrifugeg under 1500rpm for 15 minutes for serum. Serum was collected and placed in-80℃refrigerator, TNF-a activity was measured with enzyme-linked immunosorbent assay (ELISA). Blood transplantation in rats after abdominal aorta, separating out the graft under the microscope. After The saline washing, the home of 4% paraformaldehyde 6-24h, conventional dehydrated, embedded in paraffin, made into 2μm paraffin, and eventually HE staining. Then the number of adventitial monocytes was observed. SPSS13.0 statistical software was used for data processing, measurement data were presented as mean±standard deviation (s), the inter-groups were analyzed using repeated measures analysis of variance of data, multi-double comparision with a multiple t test, P<0.05 as statistical difference significance.Results1. Pathological changes:a large number of monocytes could be seen in the experimental group, compared with the control group, with significant differences (P <0.05). Immune intervention group also showed obvious infiltration of mononuclear cells, but the experimental group were significantly higher (P<0.05), the difference was significant.2. TNF-αactivity:the activity of TNF-αin the experimental group was significantly increased, compared with the control group, with significant difference (P＜0.05). significantly increased TNF-αactivity can also be found in Immune intervention group, but the experimental group were significantly higher(P<0.05).Conclusion1. cryopreserved aortic graft in allograft transplantation has obvious immunological rejection. 2. Cyclosporin A clearly inhibited the activity of mononuclear cell infiltration and TNF-αin the aortic allograft transplantation.
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