体外血脑屏障模型装置-体外3D细胞屏障培养

flocel体外血脑屏障实验模型系统

—Flocel体外三维动态血脑屏障（Dynamic In Vitro Blood-Brain Barrier Model）

Blood-Brain Barrier Model）

体外血脑屏障测量模型一般包括：

1）跨细胞膜电阻测量（TEER 检测）系统

2）计算机控制的脉动泵

3）flocel控制软件

是Flocel公司生产和销售的一个更实际的、动态的体外血脑屏障（DIV-BBB™）模型，更准确地反映真正的血脑屏障特性。

迄今为止，研究者已经使用静态BBB模型或动物模型进行了测试。和这些方法对比，flocel的DIV-BBB模型的优势：

更的药代动力学和毒理学研究

● 更准确地反映体内血脑屏障特性

● 模仿重要的内皮细胞-星形胶质细胞相互作用

● 电测量血脑屏障的完整性

● 能使用真实的人体细胞

● 形成比现有静态模型更紧密的连接

● 可大幅降低药物开发成本

特点

与传统血脑屏障系统相比，Flocel体外动态血脑屏障系统模型特点如下：

• 可以做更准确的药代动力学和毒物学的研究

• 更清楚准确的反应了体内血脑屏障的特性

• 模拟重要的内皮细胞与星形胶质细胞之间的作用

• 用电力方法检测了血脑屏障的完整性

• 可以用真实的细胞做实验

• 比现存的静态模型更能形成紧密的连接

• 降低药物研发的成本

1.DIV-BBB™ 管腔

动态血脑屏障参数

2.跨细胞膜电阻测量（TEER 检测）系统

TEER检测系统为研发人员提供了一个快速、简便地评估血脑屏障完整性方法，此外，电阻抗值（>1000 Ω-cm）也非常接近体内数值。TEER检测系统同时配带了所需检测软件、电线和衬板，可供4个DIV-BBB管腔同时使用。其中检测软件可以自定义设置泵的流速、频率、波形等参数。其它特性及优点见下表：

- Transcending the Transwell -

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"...the exposure to intraluminal flow plays an essential role in promoting endothelial cell differentiation and increasing BBB tightness..."

"...in contrast to the Transwell apparatus...endothelial cells grown under dynamic conditions ...develop in a monolayer fashion, thus mimicking the structural physiology of capillaries in vivo..."

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

Janigro et al., 2006

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Our mission at Flocel Inc. is not only to to provide high-quality products and services for in vitro 3D cell barrier culture, but also to convey -with integrity and transparency- the advantages of our DIV-BBB 2.0 system compared to other approaches --such as the Transwell.

- Stronger Barriers, Stronger Data -

A comparative study between cell barriers cultured in a static flow (i.e., Transwell) and dynamic flow (i.e., DIV-BBB) environment showed that fluid flow conditions greatly influence how a cell barrier develops. Trans-endothelial electrical resistance (TEER) across the DIV-BBB culture (B) increased to values 10-fold higher than those recorded in the Transwell (A), and much closer to values observed in vivo. This is because dynamic flow causes shear stress on the apical surface of the cell, and influences cell development and function.

This concept is reiterated in the inset microscope images of the figure above: A cell culture that has been subjected to dynamic flow and physiologically-representative levels of shear stress (B) resulted in a confluent monolayer of cells expressing tight junctions. The cell barrier in under static flow (A) receives no shear stress, and instead forms a multilayer of cells with less tight junction organization.

- Higher Selective Permeability -

Owing to the stronger and more physiologically-accurate cell barrier grown under dynamic flow conditions, the DIV-BBB also presents a more stringent regulation of selective permeability. Tests conducted between cells cultured in the DIV-BBB (C) and Transwell (D) for passage of phenytoin (an epileptic drug with in vivo permeability levels of 0.0001 cm/s) showed markedly higher levels of permeability through the Transwell than the DIV-BBB, and 4-fold higher than in vivo. The stronger and more physiologically-accurate cell barriers grown under the dynamic fluid conditions of the DIV-BBB allow for more accurate testing of drug permeability and pharmacokinetics.

- What if I already own Transwell products? -

If you would prefer to continue using your Transwell products (such as Endohm-6, Endohm-12, Endohm-24SNAP cell culture chambers or any "chopstick" electrodes), we also offer a Trans-endothelial Electrical Resistance (TEER) Measurement Unit that is compatible with these Endohm products, and much more versatile! Not only does our TEER Measurement Unit allow for frequency sweeps between 0.1 Hz and 1,000 Hz (0.1 Hz sampling resolution), it can be directed by the user to automatically sample single-frequency and frequency sweep data for an indefinite amount of time, and save this data to a .xls or .csv save file. No  more pushing a button and jotting down the TEER value every time you want to take a measurement!

测试服务

世联博研和Flocel Inc.联合，提供以合同为基础的体外 BBB渗透性测试。费用结构由待测化合物的数量和测试的复杂性决定。这项服务在克利夫兰基金会，斯坦福大学和欧洲的实验室进行。我们还提供脑生物标志物的咨询服务和测试仪器，并通过分析外周血检测人体受试者血脑屏障的完整性，提供诊断患者或运动员血脑屏障的方法。
轻型颅脑损伤（MHI和MTBI）占颅脑损伤的95%；诊断和早期管理包括计算机断层扫描（CT）或住院观察，但是这些选项都不理想。在医院观察是不经济的；CT有时是不切实际的，涉及潜在的有害电离辐射。GFAP和S100等脑蛋白在体液中表达水平与许多神经系统疾病有关联性。Flocel开发了商业化的血液测试小型工具，给创伤性脑损伤进行前期及时诊断，防止严重的延迟性后果。

发表文献：

- Publications -

• The role of shear stress in blood-brain barrier endothelial physiology.
       Cucullo L, Hossain M, Puvenna V, Marchi N, Janigro D.

• A dynamic in vitro BBB model for the study of immune cell trafficking into the central nervous system.
       Cucullo L, Marchi N, Hossain M, Janigro D.

• Pattern of P450 expression at the human blood-brain barrier: roles of epileptic condition and laminar flow.
       Ghosh C, Gonzalez-Martinez J, Hossain M, Cucullo L, Fazio V, Janigro D, Marchi N.

• Tobacco smoke: a critical etiological factor for vascular impairment at the blood-brain barrier.
       Hossain M, Sathe T, Fazio V, Mazzone P, Weksler B, Janigro D, Rapp E, Cucullo L.

• Immortalized human brain endothelial cells and flow-based vascular modeling: a marriage of convenience for rational neurovascular studies.
       Cucullo L, Couraud PO, Weksler B, Romero IA, Hossain M, Rapp E, Janigro D.

• Side by side comparison between dynamic versus static models of blood-brain barrier in vitro: a permeability study.
       Santaguida S, Janigro D, Hossain M, Oby E, Rapp E, Cucullo L.

• Glycerophosphoinositol and dexamethasone improve transendothelial electrical resistance in an in vitro study of the blood-brain barrier.
       Cucullo L, Hallene K, Dini G, Dal Toso R, Janigro D.

• A new dynamic in vitro model for the multidimensional study of astrocyte-endothelial cell interactions at the blood-brain barrier.
       Cucullo L, McAllister MS, Kight K, Krizanac-Bengez L, Marroni M, Mayberg MR, Stanness KA, Janigro D.

- Posters -

• A Dynamic Humanized drug resistant In Vitro Blood-Brain Barrier Model to assess the permeability of relevant CNS drugs

• Development of a novel blood-brain barrier model by coupling Immortalized human brain endothelial cells with flow-based cell culture technologies

• Glioblastoma Cell Line Metabolism Under Dynamic and Static Conditions: Effects on tumor growth and BBB integrity

• Humanized in vitro blood-brain barrier models to screen for brain penetration of antiepileptic drugs

• Effect of Shear stress on BBB endothelial cells: A proteomic study by 2-dimensional protein electrophoresis