^(125)I标记重组人β-神经生长因子在血脑屏障中通透性的研究

Study on permeability of the recombinant β-NGF through blood-brain barrier

目的 研究 β 神经生长因子 (NGF)在血脑屏障中的通透性。 方法 将重组真核表达载体PcDNA3 β NGF以脂质体转染COS 7细胞。将细胞培养上清经离子交换树脂层析进行分离纯化 ,观察纯化蛋白质对PC12细胞突起生长的作用。以12 5I标记纯化蛋白质 ,Wistar大鼠尾静脉注射 ,以γ测量仪检测脑组织放射性。结果 PC12细胞培养结果示 :纯化产物可促使其突起生长 ;注射后 30min ,脑组织放射性达高峰。结论 纯化的重组人β NGF具有良好的生物学活性 。

Objective Study on the permeability of rhβ nerve growth factors (NGF) through blood brain barrier (BBB) to provide scientific basis for research of β NGF in clinical therapeutic application. Methods To transfect the COS 7 cell line with recombination expressive vector, PcDNA3 β NGF, by lipofectamine. The proteins, produced in the supernatant by the transfected cells, was isolated and purified by ion exchange chromatography on carboxymethyl cellulose. The biological activity of the purified protein was analyzed by the prospectation of processes grown out from PC12 cell line; and the protein was labelled with 125 I and injected i.v into rats, and then the radioactivity of rat brain tissue was analyzed by γ scintillometer. Results The purified protein could stimulate the process growth of PC12 cell line and the result of γ scintigraphy analysis showed that the radioactivity achieved high level in rat brain tissue 30 min after the protein injection. Conclusion Purified rhβ NGF has good biological activity and it could partially penetrate the BBB.