7. Dynamic Flow Assay in a Parallel Plate Flow Chamber John T. Patton~GlycoTech Corporation, Rockville, Maryland 20850 Flow assays allow visualization of cell adhesion under well-defined wall shear stress. The visualization of the different events of cell adhesion can be quantified by selective image acquisition and subsequent image processing. Flow assays are uniquely suited to the investigation of adhesive events which occur very rapidly in a time scale shorter than that of most static adhesion assays. In addition, events subsequent to the initial events can be studied such as cell stabilization and spreading giving some insight into the kinetics of particular cell-cell or cell-substrate adhesive behavior. Materials: Microscopy: Inverted-stage microscope configured for phase contrast and fluorescence operation Objective lens (6.3 x, 10 x, 40 x) Stage incubator Biological: Cell suspension (neutrophils, cancer cells) Cell monolayer or coated substrate in 35 mm dishes Adhesion media (culture media serum-free with 12 mM Hepes) Fibronectin (human plasma) Bovine serum albumin (BSA) Flow Chamber System: Flow chamber deck with gasket and tube fittings 35 mm tissue culture dishes Harvard syringe pump Glass syringes to fit on pump (3, 5, 20, or 60 cc) Silastic tubing Stopcocks Vacuum pump Computer/Electronics: Digital image acquisition and processing system Display monitor Video recorder CCD camera with controller Time-date generator Computer with interface to image system Storage device for images Protocol: Cell Monolayer Preparation 1. Coat dishes with human fibronectin (FN) by adding 1 ml of 5.5?g/ml FN solution to each dish. 2. Incubate for 30 min. at room temperature. 3. Aspirate solution out of each dish. 4. Add 2 ml of cell suspension (Huvecs, CHO cells) to each dish at seeding density of 0.5-3.0 x 105 cells/ml depending on time required to reach confluence. 5. After 1-5 days, use dishes with confluent monolayer in flow assay. Feed cells every 2-3 days, but usually not with 48 hrs. of flow assay. Coated Substrate Preparation 1. Outline a coating region (5 mm diameter) for coating substrate in the center of each dish with marking pen. 2. Add 20?l of solution containing substrate at a concentration of 10?g/ml to coating region. Incubate 1 hr. 3. Aspirate off liquid, add 20?l of 1% BSA to block for 1 hr. 4. Aspirate off BSA, add 20?l of inhibitor for 1 hr. 5. Dishes are ready for use in flow assay. Flow Assay Using Parallel Plate Flow Chamber 1. Turn on stage incubator and warm adhesion media to 37?C 1 hr. prior to beginning flow assay. 2. Assemble flow system apparatus connecting inlet, outlet, and vacuum lines to the flow chamber deck. Fill system with media and remove all air from system. 3. Fill inlet reservoir with cell suspension. For assays using cell monolayers, 106 cells/ml is recommended. For coated substrate assays, use 105 cells/ml. 4. Attach dish to flow chamber deck by holding the deck inverted, place a small bubble of media on flow path area, then place 35 mm dish on the deck. Vacuum will hold dish on deck. Make sure dish was attached with no air bubbles in the flow path. 5. Place assembled chamber on microscope stage. 6. Initiate flow of cells syringe pump connected to outlet flow chamber at a shear stress in the range of 0.1-4.0 dynes/cm2. 7. Allow cells to flow for sufficient time to get an adequate number of cells interacting with the cell monolayer or coated surface. Generally 3-10 min. is used. 8. Begin image acquisition. Collect images at 7-10 locations on the dish. Generally 3 dishes at a given experimental condition gives enough data to show statistical differences between treatments. 9. After images are acquired on all dishes, perform image analysis to quantify the flow assay. References: (1) Lawrence, M.B., McIntire, L.V., Eskin, S.K., (1987), Effect of flow on polymorphonuclear leukocyte/ endothelial cell adhesion, Blood 70: 1284-1290. (2) Patton, J.T., Menter, D.G., Benson, D.M., Nicolson, G.L., McIntire, L.V., (1993), Computerized analysis of tumor cells flowing in a parallel plate chamber to determine their adhesion stabilization lag time, Cell Motility and the Cytoskeleton26: 88-98. (3) Jones, D.A., Abbassi, O., McIntire, L.V., McEver, R.P., Smith, C.W., (1993), P-selectin mediates neutrophil rolling on histamine-stimulated endothelial cells, Biophysical Journal 65: 1560-1569. NE-1000程控注射泵,货促销 NE-1000 Programmable Single Syringe Pump 技术参数: 注射器的容量达到60ml 注射速率可以从0.73uL/hr-2100mL/hr调节 节省空间的设计,小巧结实的外观,为你实验室节省空间 主要特点: 1.有注入和回抽功能 2.可编程控制,*大41阶命令(注射的速率、注射的容量、插入暂停) 3.一台电脑可以控制100台注射泵 4.注射的精度小于正负1% New Era系列注射器微量注射泵可用于动物实验,同时具有注射和回抽功能,可控制流速,可通过程序控制注射流量。相比较其它同类产品,New Era泵提供了更强的功能,然而价格确比其它品牌要低。这让New Era泵嬴得了大量的客户。客户向其它的同事推荐这种微量注射泵。对于需要双泵的用户而言,New Era系统的优势是巨大的。它以不高于其它品牌双通道泵的价格,提供两台单通道泵。这两台泵可以单独控制,从事不同的实验,也可以互联,运行相同的参数或程序。功能和实用性均远超其它厂家的双通道泵。 New Era微量注射泵可兼容市场上绝大部分的注射器。 主要特性: 可单机操作也可电脑控制 (RS-232插头) 可注射也可回抽 (双向) 可用1~60cc注射器 可选择注射流量及流速控制程序,有41种选择 可将多个泵连接组合成一个系统 (双筒), *大可达100泵; 单筒NE-1000、双筒NE-4000, 6筒NE-1600、8筒NE-1800整机选择. 注射速率pumping rate: NE-1000: 0.73 ml/小时~2100ml/小时 NE-4000: 0.73 ml/小时~2100ml/小时 NE-1600: 0.568 ml/小时~1337ml/小时 NE-1800: 0.568 ml/小时~380 ml/小时 技术参数: 注射器尺寸 1-60ml,or 0.5-5μl微量注射器 注射器数目 1,6,8 依据泵的型号变化 驱动方式 步进马达,1/8 to 1/2步进方式 转轴*大步进数 400/s 马达步进距离 0.850μm(1/2step) 马达/转轴齿数 15/28 速度(max/min) 5.1cm/min 0.0042cm/hr 泵流量 *大:1699mL/hr,60ml注射器 *小:0.73μL/hr,1ml注射器 *大推力 35lb *小流速时 18lb *大流速时 程序数 41 电源 220V,50-60Hz 尺寸 22.9×14.6×11.4 cm 重量 1.6kg
技术参数:
注射器的容量达到60ml 注射速率可以从0.73uL/hr-2100mL/hr调节 节省空间的设计,小巧结实的外观,为你实验室节省空间
主要特点:
1.有注入和回抽功能 2.可编程控制,*大41阶命令(注射的速率、注射的容量、插入暂停) 3.一台电脑可以控制100台注射泵 4.注射的精度小于正负1%
New Era系列注射器微量注射泵可用于动物实验,同时具有注射和回抽功能,可控制流速,可通过程序控制注射流量。相比较其它同类产品,New Era泵提供了更强的功能,然而价格确比其它品牌要低。这让New Era泵嬴得了大量的客户。客户向其它的同事推荐这种微量注射泵。对于需要双泵的用户而言,New Era系统的优势是巨大的。它以不高于其它品牌双通道泵的价格,提供两台单通道泵。这两台泵可以单独控制,从事不同的实验,也可以互联,运行相同的参数或程序。功能和实用性均远超其它厂家的双通道泵。
New Era微量注射泵可兼容市场上绝大部分的注射器。
主要特性:
NE-1000: 0.73 ml/小时~2100ml/小时
NE-4000: 0.73 ml/小时~2100ml/小时
NE-1600: 0.568 ml/小时~1337ml/小时
NE-1800: 0.568 ml/小时~380 ml/小时
技术参数:
注射器尺寸 1-60ml,or 0.5-5μl微量注射器
注射器数目 1,6,8 依据泵的型号变化
驱动方式 步进马达,1/8 to 1/2步进方式
转轴*大步进数 400/s
马达步进距离 0.850μm(1/2step)
马达/转轴齿数 15/28
速度(max/min) 5.1cm/min 0.0042cm/hr
泵流量 *大:1699mL/hr,60ml注射器
*小:0.73μL/hr,1ml注射器
*大推力 35lb *小流速时
18lb *大流速时
程序数 41
电源 220V,50-60Hz
尺寸 22.9×14.6×11.4 cm
重量 1.6kg