论文部分内容阅读
目的 用大肠杆菌表达色素上皮细胞衍生因子(PEDF),及评价其在脑胶质瘤血管新生中的作用。方法 构建pET41 /PEDF表达载体,用金属亲和层析(HisTag)和阴离子交换层析纯化重组蛋白,并以管腔形成试验验证重组蛋白活性。同时,采用酶联免疫吸附试验(ELISA)测定血管内皮细胞生长因子(VEGF)与血小板反应素1 (TSP- 1)的变化。结果 用基因工程手段获得终产量为3 8mg/L,可抑制内皮细胞管腔形成的PEDF蛋白; PEDF可下调VEGF(减少1 8倍)和上调TSP -1(增高5 3倍)的表达。结论 PEDF可能是抑制脑胶质瘤新生血管形成的主要因素。
Objective To express the pigment epithelium-derived factor (PEDF) in Escherichia coli and to evaluate its role in glioma angiogenesis. Methods The pET41 / PEDF expression vector was constructed. The recombinant protein was purified by metal affinity chromatography (HisTag) and anion exchange chromatography. The activity of recombinant protein was verified by luminal formation assay. At the same time, the changes of vascular endothelial growth factor (VEGF) and thrombospondin 1 (TSP-1) were detected by enzyme-linked immunosorbent assay (ELISA). Results The PEDF protein with a final production of 38 mg / L was inhibited by genetic engineering. PEDF could down-regulate VEGF (down by 18-fold) and up-regulate TSP-1 (up to 35-fold). Conclusion PEDF may be the main factor inhibiting the angiogenesis of glioma.