Stanness K A, Westrum L E, Fornaciari E, Mascagni P, Nelson J A, Stenglein S G, Myers T, Janigro D
Department of Neurological Surgery, University of Washington, Harborview Medical Center, Seattle 98104, USA.
Brain Res. 1997 Oct 17;771(2):329-42. doi: 10.1016/s0006-8993(97)00829-9.
Cell culture models have been extensively used for studies of blood-brain barrier (BBB) function. However, several in vitro models fail to reproduce some, if not most, of the physiological and morphological properties of in situ brain microvascular endothelial cells. We have recently developed a dynamic, tridimensional BBB model where endothelial cells exposed to intraluminal flow form a barrier to ions and proteins following prolonged co-culturing with glia. We have further characterized this cell culture model to determine whether these barrier properties were due to expression of a BBB phenotype. Endothelial cells of human, bovine or rodent origin were used. When co-cultured with glia, intraluminally grown endothelial cells developed features similar to in vivo endothelial cells, including tight junctional contacts at interdigitating processes and a high transendothelial resistance. This in vitro BBB was characterized by the expression of an abluminal, ouabain-sensitive Na/K pump, and thus favored passage of potassium ions towards the lumen while preventing K+ extravasation. Similarly, the in vitro BBB prevented the passage of blood-brain barrier-impermeant drugs (such as morphine, sucrose and mannitol) while allowing extraluminal accumulation of lipophylic substances such as theophylline. Finally, expression of stereo-selective transporters for Aspartate was revealed by tracer studies. We conclude that the in vitro dynamic BBB model may become an useful tool for the studies of BBB-function and for the testing of drug passage across the brain endothelial monolayer.
细胞培养模型已被广泛用于血脑屏障（BBB）功能的研究。然而，一些体外模型无法重现原位脑微血管内皮细胞的部分（如果不是大部分）生理和形态特性。我们最近开发了一种动态三维血脑屏障模型，其中暴露于腔内流动的内皮细胞在与神经胶质细胞长期共培养后，对离子和蛋白质形成屏障。我们进一步对这个细胞培养模型进行了表征，以确定这些屏障特性是否归因于血脑屏障表型的表达。使用了人、牛或啮齿动物来源的内皮细胞。当与神经胶质细胞共培养时，腔内生长的内皮细胞呈现出与体内内皮细胞相似的特征，包括在指状突处的紧密连接以及高跨内皮电阻。这种体外血脑屏障的特征是表达一种腔外哇巴因敏感的钠钾泵，因此有利于钾离子向腔内通过，同时防止钾离子外渗。同样，体外血脑屏障阻止血脑屏障不通透的药物（如吗啡、蔗糖和甘露醇）通过，同时允许脂溶性物质如茶碱在腔外积累。最后，示踪研究揭示了天冬氨酸立体选择性转运体的表达。我们得出结论，体外动态血脑屏障模型可能成为研究血脑屏障功能和测试药物穿过脑内皮单层的有用工具。
