Side by side comparison between dynamic versus static models of blood–brain barrier in vitro: A permeability study

Endothelial cells in vivo are continuously exposed to shear stress, a tangential force generated by the flow of blood across their apical surfaces that affects endothelial cell structure and function. By contrast, the Transwell apparatus cannot reproduce the presence of intraluminal blood flow that is essential for the formation and differentiation of the BBB. In contrast, the dynamic in vitro model of the BBB (DIV-BBB) mimics both functionally and anatomically the brain microvasculature, creating quasi-physiological conditions for co-culturing human and non-human endothelial cells and astrocytes in a capillary-like structure. We used intraluminal bovine aortic endothelial cells (BAEC) co-cultured with extraluminal glial cells (C6) to obtain elevated trans-endothelial electrical resistance (TEER) and selective permeability to sucrose and phenytoin. The experiments were performed in parallel using Transwell systems DIV-BBB models and data were then cross compared. By contrast with Transwell, C6 and BAEC co-cultured in the DIV-BBB demonstrated predominantly aerobic metabolism evidenced by a robust increase in glucose consumption that was paralleled by a similar change in lactate production. BAEC exposed to glia under dynamic conditions grow in a monolayer fashion and developed a more stringent barrier as demonstrated by high TEER values and a selective permeability to [14C] phenytoin and the well-known paracellular marker [3H] sucrose. In conclusion, these data demonstrate that the exposure to intraluminal flow plays an essential role in promoting endothelial cell differentiation and increasing BBB tightness, thus making the use of the DIV-BBB well suited for pharmacological studies.

体内的内皮细胞持续暴露于剪切应力，这是一种由血液流过其顶端表面产生的切向力，会影响内皮细胞的结构和功能。相比之下，Transwell 设备无法再现对 BBB 的形成和分化至关重要的腔内血流的存在。相比之下，BBB 的动态体外模型 (DIV-BBB) 在功能和解剖学上模拟大脑微血管系统，为在毛细血管样结构中共培养人类和非人类内皮细胞和星形胶质细胞创造准生理条件。我们使用管腔内牛主动脉内皮细胞 (BAEC) 与管腔外神经胶质细胞 (C6) 共培养以获得升高的跨内皮电阻 (TEER) 和对蔗糖和苯妥英钠的选择性通透性。使用 Transwell 系统 DIV-BBB 模型平行进行实验，然后交叉比较数据。与 Transwell 相比，在 DIV-BBB 中共培养的 C6 和 BAEC 表现出主要的有氧代谢，葡萄糖消耗的强劲增加证明了这一点，同时乳酸产生也发生了类似的变化。在动态条件下暴露于胶质细胞的 BAEC 以单层方式生长并形成更严格的屏障，如高 TEER 值和对 [14C] 苯妥英和众所周知的细胞旁标记物 [3H] 蔗糖的选择性渗透所证明的。总之，这些数据表明，暴露于腔内流动在促进内皮细胞分化和增加 BBB 紧密度方面起着重要作用，从而使 DIV-BBB 的使用非常适合药理学研究。

文献原文：https://pubmed.ncbi.nlm.nih.gov/16857178/