Mice aorta loop grafting: A new model which separate vascular rejection and neointimal formation in chronic rejection

Objective: To study the cause and mechanism of transplantation vasculopathy which characterized by accelerated graft arteriosclerosis (AGA) , we established a mouse aorta graft model. Methods: A segment of thoracic aortas of B10. A (2R) mice were transplanted to C57BL/10 mice abdominal aorta by end to side anastomoses. The different time point collected grafts were analyzed by morphological, histochemical and electro microscopic methods. Results: Rejection was manifested as a concentric progressive destruction of the smooth muscle cells. In contrast, the endothelial inflammation and subsequent neointimal proliferation characteristic of AGA was localized to the regions of turbulent flow, i. e. the junction of the graft with the recipient aorta. Conclusion: This model separates the processes of rejection and neointimal formation which usually manifested together in the lesion of AGA, elucidate that different mechanisms control vascular rejection and neointimal formation in chronic rejection.