Development of an organotypic in-vitro model of the blood-brain barrier

描述（由申请人提供）： 血脑屏障（BBB）是由微血管和毛细血管形成的紧密屏障，其控制营养物质、液体、代谢产物和药物在血液和脑之间的通过。BBB的不平衡涉及许多困扰大脑的主要病理，例如阿尔茨海默病、中风和癌症。虽然神经治疗是制药行业中最大和增长最快的市场之一，但由于缺乏可靠预测体内BBB渗透性的体外测定，目前进展受到阻碍。现有的模型都没有充分复制体内器官型微环境，这被视为实现体内功能的关键。我们以前已经开发了一个3D模型，用于体外血管生成的研究，包括小的流体设备与胶原蛋白填充室。我们打算将我们的模型发展成具有以下主要属性的血脑屏障的器官型体外模型：（1）组织工程化的内皮细胞微血管，由以生理比例和结构排列的周细胞和星形胶质细胞包围;（2）内皮细胞、周细胞和星形胶质细胞之间的直接接触;（3）类似于CNS的间质环境的细胞外基质（ECM）;（4）向内皮提供剪切应力的腔流;（5）严格控制的物理和化学条件;（6）可适用于现有高通量分析平台的批量生产的一次性流体装置。在第一阶段，我们将建立一个模型的原型，该模型包括脑特异性细胞外基质中的中央BBB微血管，周围环绕着周细胞和星形胶质细胞-诱导和维持屏障紧密性的细胞。在第二阶段，我们将致力于商业产品的开发，包括将流体装置适应于高通量分析平台。我们预测，我们的模型将促进一些毁灭性疾病的治疗取得重大进展。 公共卫生相关性： 成功开发治疗中枢神经系统（CNS）疾病如阿尔茨海默氏病、帕金森氏病、中风、脑癌和脑转移的药物的主要障碍是这些药物不能穿过血脑屏障（BBB）。这种天然屏障的功能是保护CNS免受潜在有害分子的侵害，但不幸的是，它也会阻止潜在有益药物的渗透。评估药物是否会穿过血脑屏障的困难使得新的神经系统药物的开发成为一项困难且异常不成功的任务。出于这个原因，成功预测体内药物BBB渗透性的体外模型对于神经制药工业是至关重要的。我们提出了一种体外模型的发展，模仿自然的血脑屏障结构，包括灌注微血管。该模型有望成为一个有价值的系统，药物开发人员以及中枢神经系统的研究人员在学术界。

DESCRIPTION (provided by applicant): The blood-brain barrier (BBB) is a tight barrier formed by microvessels and capillaries controlling the passage of nutrients, fluids, metabolic products and drugs between the blood and the brain. Imbalance of the BBB is involved in a number of major pathologies afflicting the brain, such as Alzheimer's disease, stroke, and cancer. Although neurotherapeutics are among the largest and fastest growing markets in the pharmaceutical industry, progress is currently impaired by the lack of in-vitro assays that reliably predict in-vivo BBB permeability. None of the existing models adequately replicates the in-vivo organotypic microenvironment, which is seen as a key for achieving in-vivo-like functionality. We have previously developed a 3D model for the study of in-vitro angiogenesis, consisting of small fluidic devices with a collagen-filled chamber. We intend to advance our model into an organotypic in-vitro model of the blood-brain barrier with the following main attributes: (1) a tissue-engineered endothelial-cell microvessel, surrounded by pericytes and astrocytes arranged in physiological ratio and architecture; (2) direct contact between endothelial cells, pericytes, and astrocytes; (3) an extracellular matrix (ECM) that resembles the interstitial environment of the CNS; (4) luminal flow providing shear stress to the endothelium; (5) tightly-controlled physical and chemical conditions; (6) a mass- produced, disposable fluidic device that can be adapted for use in existing high-throughput analysis platforms. In Phase 1, we will establish the prototype of a model that comprises a central BBB-microvessel in a brain-specific extracellular matrix, surrounded by pericytes and astrocytes--cells that induce and maintain barrier tightness. In Phase 2 we will pursue the development of a commercial product, including the adaptation of the fluidic device to high- throughput analysis platforms. We predict that our model will facilitate a significant progress in the therapy of a number of devastating diseases. PUBLIC HEALTH RELEVANCE: A major obstacle to the successful development of drugs that treat diseases of the central nervous system (CNS) such as Alzheimer's, Parkinson's, stroke, brain cancers, and metastasis to the brain, is the inability of these drugs to cross the blood-brain barrier (BBB). This natural barrier, whose function is to protect CNS from potentially harmful molecules, unfortunately also prevents penetration of potentially beneficial drugs. The difficulty in assessing whether or not drugs will cross the BBB makes the development of new neurologic drugs a difficult and unusually unsuccessful task. For this reason, in- vitro models that successfully predict in vivo drug BBB-permeability are of paramount importance for the neuropharmaceutical industry. We propose the development of an in- vitro model that mimics the natural BBB architecture, including perfused microvessels This model promises to become a valuable system for drug developers as well as to CNS researchers in academia.