Development of a BBB model to study transendothelial cell migration

描述（由申请人提供）：在体外再现脑血管节段的生理特征是一个关键问题。适当的血管模型可以显着帮助理解的机制，并改善疾病的药理学，其中白细胞迁移通过血管的血管的作用被证明。由于之前的支持（I期），我们能够原型化和测试驱动允许白细胞外渗的BBB（DIV-BBB）的新动态体外模型。我们最初的努力旨在以可重复的方式刺穿中空纤维;结果最近发表。我们发现，手动穿孔的中空纤维允许白细胞通过血脑屏障，以响应促炎刺激和血液动力学变化。我们还能够通过改变流变学参数（例如，改变系统的剪切应力）。此外，我们最近开发了一种系统，以机械方式“拉伸”中空纤维，将孔径增加到约5 μ m的生理相关尺寸。控制牵引施加到纤维的末端，扫描电子显微镜显示拉伸纤维内的扩大的孔。为了进一步利用这种新的BBB模型提供的商业机会，我们提出了以下II期特定目标：优化允许白细胞外渗的脑血管系统的动态体外毛细血管-小静脉模型的性能。确定由具有不同透壁渗透性的纤维组成的对照和患病毛细血管-微静脉节段中白细胞外渗的模式（来自目标1）。将使用这些DIV-BBB模型获得的结果与其他最先进的体外BBB模型进行比较。 我们将首先针对多发性硬化症和癫痫研究和药物开发定制DIV毛细血管-微静脉系统的使用。我们已经组建了一个多学科的研究人员和专家团队，在白细胞迁移通过血管系统的领域。其他临床相关场所详见商业化计划。鉴于我们的初步结果和本申请中详细描述的确认性进展报告，并鉴于与此同时新药的开发仍然是神经系统疾病治疗中的一个主要问题，我们相信，强大的成就记录和旨在改善药物开发的合理实验设计的结合是该第二阶段提案的基本方面。

DESCRIPTION (provided by applicant): Reproducing in vitro the physiological characteristics of brain vascular segments represents a critical issue. Adequate modeling of the cerebrovasculature could significantly help understand the mechanisms and improve the pharmacology of disease where a role for leukocytes migrating across the cerebrovasculature is demonstrated. Thanks to the previous support (Phase I) we were able to prototype and test drive a new dynamic in vitro model of the BBB (DIV- BBB) permissive for leukocyte extravasation. Our initial effort aimed at piercing hollow fibers in a reproducible manner; the results were recently published. We found that manually perforated hollow fibers allow leukocytes passage across the BBB in response to pro-inflammatory stimuli and hemodynamic changes. We were also able to produce a capillary-venule segment by varying the rheological parameters (e.g., changing the shear stress) of the system. In addition we recently developed a system to mechanically "stretch" the hollow fibers increasing the pore size up to the physiologically relevant size of ~5 ¿m. Controlled traction was applied to the end of the fibers and scanning electron microscopy showed enlarged pores within the stretched fiber. To further the commercial opportunity afforded by this new BBB model, we propose the following Phase II Specific Aims: To optimize the performance of a dynamic in vitro capillary-venules model of the brain cerebrovasculature permissive for leukocyte extravasation. To determine the pattern of leukocytes extravasation in control and diseased capillary-venules segments composed of fibers with different transmural permeability properties (from Aim 1). To compare the results obtained using these DIV- BBB models to other state-of-art in vitro BBB models. We will initially tailor the use of the DIV capillary-venules system to multiple sclerosis and epilepsy research and drug development. We have assembled a multi-disciplinary team of investigators and experts in the field of leukocyte migration across the cerebrovasculature. Additional clinically relevant venues are detailed in the Commercialization Plan. Given our preliminary results and the confirmatory progress report described in detail in this application, and given the fact that i the meantime development of new drugs has remained a major issue in the treatment of neurological diseases, we believe that the combination of a strong record of accomplishment and sound experimental design aimed at improving drug development are fundamental aspects of this Phase 2 proposal.