Changes in the number of endothelial progenitor cells from peripheral blood and significance in mouse abdominal aortic allografts / 中华器官移植杂志

ABSTRACT

Objective To investigate changes in the number of endothelial progenitor cells (EPC) from peripheral blood and pathological feature in the development of transplant arteriosclerosis in mouse abdominal aortic allografts, and discuss their correlations. Methods A segment of abdominal aorta was transplanted orthotopically from C57BL/6 to Balb/c mice. The grafts were harvested at 3rd day, 2nd week, 4th week and 6th week after the operation and studied by light and electronic microscopy. Regional changes in the lumen and intima were measured with computer imaging analysis system. EPC from peripheral blood were quantified by flow cytometry. Results Endothelium injury and inflammatory cells infiltration were seen in the aortic allografts at 3rd day after transplantation.Neointimal lesions and acute rejection were observed as early as 2nd week after surgery. The lumen of allografts was significantly narrowed due to neointima hyperplasia and had progressed at 4th and 6th week postoperatively. The number of circulation EPC was increased from 1 st day after operation and reached the peak at 3rd day. Thereafter the number of EPC was decreased rapidly and significantly less at 14th and 28th day postoperation than that pre-operation. Conclusion Abdominal aortic transplantation from C57BL/6 to Balb/c mice presents typical pathological feature of transplant arteriosclerosis. The number of EPC from peripheral blood is related to the process of injured endothelial repair and neointima formation of aortic grafts. EPC count may be considered a novel biological marker and therapeutic intervention for transplant arteriosclerosis.