體外血腦屏障模型裝置-體外3D細胞屏障培養

flocel體外血腦屏障實驗模型系統

—Flocel體外三維動態血腦屏障（Dynamic In Vitro Blood-Brain Barrier Model）

Blood-Brain Barrier Model）

體外血腦屏障測量模型一般包括：

1）跨細胞膜電阻測量（TEER 檢測）系統

2）計算機控制的脈動泵

3）flocel控制軟件

是Flocel公司生產和銷售的一個更實際的、動態的體外血腦屏障（DIV-BBB™）模型，更準確地反映真正的血腦屏障特性。

迄今為止，研究者已經使用靜態BBB模型或動物模型進行了測試。和這些方法對比，flocel的DIV-BBB模型的優勢：

更的藥代動力學和毒理學研究

● 更準確地反映體內血腦屏障特性

● 模仿重要的內皮細胞-星形膠質細胞相互作用

● 電測量血腦屏障的完整性

● 能使用真實的人體細胞

● 形成比現有靜態模型更緊密的連接

● 可大幅降低藥物開發成本

特點

與傳統血腦屏障系統相比，Flocel體外動態血腦屏障系統模型特點如下：

• 可以做更準確的藥代動力學和毒物學的研究

• 更清楚準確的反應了體內血腦屏障的特性

• 模擬重要的內皮細胞與星形膠質細胞之間的作用

• 用電力方法檢測了血腦屏障的完整性

• 可以用真實的細胞做實驗

• 比現存的靜態模型更能形成緊密的連接

• 降低藥物研發的成本

1.DIV-BBB™ 管腔

動態血腦屏障參數

2.跨細胞膜電阻測量（TEER 檢測）系統

TEER檢測系統為研發人員提供了一個快速、簡便地評估血腦屏障完整性方法，此外，電阻抗值（>1000 Ω-cm）也非常接近體內數值。TEER檢測系統同時配帶了所需檢測軟件、電線和襯板，可供4個DIV-BBB管腔同時使用。其中檢測軟件可以自定義設置泵的流速、頻率、波形等參數。其它特性及優點見下表：

- 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!

測試服務

世聯博研和Flocel Inc.聯合，提供以合同為基礎的體外 BBB滲透性測試。費用結構由待測化合物的數量和測試的復雜性決定。這項服務在克利夫蘭基金會，斯坦福大學和歐洲的實驗室進行。我們還提供腦生物標志物的咨詢服務和測試儀器，并通過分析外周血檢測人體受試者血腦屏障的完整性，提供診斷患者或運動員血腦屏障的方法。
輕型顱腦損傷（MHI和MTBI）占顱腦損傷的95%；診斷和早期管理包括計算機斷層掃描（CT）或住院觀察，但是這些選項都不理想。在醫院觀察是不經濟的；CT有時是不切實際的，涉及潛在的有害電離輻射。GFAP和S100等腦蛋白在體液中表達水平與許多神經系統疾病有關聯性。Flocel開發了商業化的血液測試小型工具，給創傷性腦損傷進行前期及時診斷，防止嚴重的延遲性后果。

發表文獻：

- 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