Effects of EDC-PEI heparinization on allogeneic vascular antigens and inflammation levels via a rat abdominal aorta transplantation model

The objective of this study was to investigate the possibility of increasing the remote patency rate of allogeneic vessel transplantation through studying the effects of N-ethyl-N-(3-dimethylaminopropyl)-carbodiimide and polyethyleneimine (EDC-PEI) heparinization on allogeneic vascular antigens and inflammation levels. Forty rats were randomly divided into the control group, the EDC group, the PEI group and the EDC-PEI group. The rat abdominal aorta was used as the object of study, and the transplanted blood vessels were pretreated with EDC as the water-soluble cross-linking agent and PEI as the heparin-coated carrier. A rat abdominal aorta allogeneic transplantation model was established. Ultrasonic examination was used for observation of patency of proximal and distal anastomosis in each group. The tissue repair after abdominal aorta transplantation in each group was examined by H&E staining. The biomechanics, denaturation temperature and blasting strength of each group were compared. The levels of IL-1, IL-6 and TNF-α in serum of rats were measured by ELISA method, and the expression of MHC-II and α-GAL antigens in blood vessels were detected by immunohistochemistry. There were different degrees of thickening and inflammatory cell aggregation in the abdominal aorta of rats in the control, EDC and PEI groups, but there was no obvious lesion in the EDC-PEI group. Compared with the four groups, the mechanical characteristics of the EDC group decreased significantly, and the stenosis rate of anastomotic stoma in the EDC group was higher than that in the EDC-PEI and PEI groups (P<0.05). The denaturation temperature of the PEI group was lower than that of the EDC and EDC-PEI groups (P<0.05). The mechanical property and vascular bursting strength in the EDC-PEI group were similar to those in the control group. At the same time, it has more significant advantages than the other three groups in removing the vascular antigens MHC-II and α-GAL and reducing the level of inflammatory reaction, thus increasing the remote patency rate of allogeneic vascular transplantation. The inflammatory response and vascular antigenicity after transplantation are effectively reduced via the rat abdominal aorta transplantation model treated with allogeneic EDC-PEI heparinization, which has a higher remote patency rate.