Gene therapy for anastomotic stenosis after arterial reconstruction

自neointimal hyperplasia is known to be critical in formation of anastomotic stenosis afterarterial bypass operation，purposes of the present study to establish the method of gene transfer into neointima andto determine the important factor(s)规范细胞周期in neointimal formation. For the first我们适合adenovirus vectors containing LacZ gene to neointima of rat carotid artery，which was induced by balloon injuryPFU/mL of virus vector promoted high efficiency transfer ofLacZ gene to neointimal cells. Miyata et al administrated the gene of mutant platelet-derived growthfactor receptor to the rat carotid neointimal cells by the above method，and showed a significant suppression of the neointimal proliferation. To study the role of cellcycle in neointimal formation，表pression of retinoblastoma protein (Rb) in balloon-injured rat carotid artery was assessed bywestern blot analysis因为Rb releases the E2F transcription factor from its binding to Rb，其中一个关键事件在细胞周期。At 1 day after balloon injury, band shift of Rb，The phosphorylation of Rb, The phosphorylation of Rb，became to be maximal at 2days after injury，在arterial media中描述cyclin D in arterial的表达式wall was also observed after balloon injury，though the expression increased gradually by 14 days after injury，indicating a discrepancy between Rb phosphorylation and cyclin D expression. Meanwhile, p27，cell cycle inhibitor，was expressed in uninjured arterial wall. The expression of p27 was down-regulated once immediatelyafter injury but increased again from 7 days after injury These results suggested that p27suppressed cyclin D after- day 7 and regulated phosphorylation of Rb of injured arterial cells。

Since neointimal hyperplasia is known to be critical in formation of anastomotic stenosis after arterial bypass operation, the purposes of the present study were to establish the method of gene transfer into neointima and to determine the important factor(s) regulating cell cycle in neointimal formation. For the first purpose, we applied adenovirus vectors containing LacZ gene to neointima of rat carotid artery, which was induced by balloon injury, and found that more than 1x10ィイD19ィエD1 PFU/mL of virus vector promoted high efficiency transfer of LacZ gene to neointimal cells. Miyata et al administrated the gene of mutant platelet-derived growth factor receptor to the rat carotid neointimal cells by the above method, and showed a significant suppression of the neointimal proliferation. To study the role of cell cycle in neointimal formation, expression of retinoblastoma protein (Rb) in balloon-injured rat carotid artery was assessed by western blot analysis, since phosphorylation of Rb releases the E2F transcription factor from its binding to Rb, which is a critical event in cell cycle. At 1 day after balloon injury, band shift of Rb, which indicates phosphorylation of Rb, was observed. The phosphorylation of Rb, became to be maximal at 2 days after injury, when maximal cell replication was detected in arterial media. The expression of cyclin D in arterial wall was also observed after balloon injury, though the expression increased gradually by 14 days after injury, indicating a discrepancy between Rb phosphorylation and cyclin D expression. Meanwhile, p27, cell cycle inhibitor, was expressed in uninjured arterial wall. The expression of p27 was down-regulated once immediately after injury but increased again from 7 days after injury These results suggested that p27 suppressed cyclin D after- day 7 and regulated phosphorylation of Rb of injured arterial cells.