Introduction
VenaT4 biochips contain 4 parallel enclosed microcapillaries separated from 4 underlying microwells via a membrane with pores sizes of 2–10 μm. Applications include migration, transmigration, invasion and chemotaxis studies of leukocytes across the membrane embedded into the biochip. ECM proteins can be coated onto the membrane separating the flow channel and microwell containing the chemokine well. Cell suspensions may then be injected using Cellix’s microfluidic pumps which supports a range of shear stresses / shear flow rates for dynamic flow-based assays. Leukocyte migration can be observed under conditions of continuously applied shear stress to mimic physiological conditions of blood vessels. VenaT4 biochips are supplied in packs of 10, facilitating 40 experiments per pack.
VenaT4 Features:
20x, 40x long working distance magnification microscopy.
4 microwells of ~14 μL each volume to immobilize chemo-attractants inside ECM gel.
Polycarbonate membrane with various pore sizes of 2–10 μm.
Compatible with Kima pump for long term studies or for slow migrating cells.
Brightfield / phase contrast / fluorescent microscopy.
Suitable for migration, transmigration, invasion and chemotaxis experiments with leukocytes and cancer cells.
Suitable for whole blood and blood cells analysis (e.g. leukocytes)
Biochip plastic is optically clear permitting detailed microscopy studies.
0.05–200 dyne/cm2 shear stresses / shear flow rates easily obtained and controlled by the Mirus Evo nanopump, ExiGo, UniGo and 4U pumps.
Shear stress / shear flow rate may be pre-set to be incrementally increased during an assay.
Real time imaging under flow conditions.
Performance and Technical Specifications:
*Considering human whole blood with a viscosity of 4.5 cP.
**Given for the flow of distilled water in a microcapillary with dimensions: 400 μm (W) x 100 μm (D) x 28 mm (L).
Applications
Organ-on-chip studies: Culture heart, lung, liver, kidney or other organ cells in 4 microwells-on-chip with media perfusion provided by Cellix's 4U or UniGo pumps. Subsequently flow drugs or cells through the overlaying microchannel enabling drug-concentration studies or transmigration and invasion studies into your organ of choice.
Chemotaxis, Transmigration & Invasion Assays: Fill microwells with gels containing chemoattractants of interest. Flow cells through overlaying microchannel and study cell adhesion, chemotaxis, transmigration and invasion into underlying microwell.
VenaT4 Biochip, Protocol #1: coating VenaT4 biochips
Step 1
The VenaT4 biochip microwells are sealed with a thin film strip. The microchannels of the VenaT4 biochip are coated using a standard yellow tip pipette by dispensing approximately 50 μL of protein (e.g. rhICAM) into each microchannel. Note the excess of liquid on the entrance and exit ports.
Step 2
The VenaT4 biochip is then placed in a humidified box and incubated at 4°C for overnight coating
Step 3
After the incubation period, turn the biochip upside-down and remove the thin-film strips. Again using a standard yellow tip pipette, add approximately 30 μL of Type I Bovine collagen gel solution with chemoattractant into the wells. Place the biochip into a humidified box kept in the CO2 incubator for 15–20 minutes at 37°C. Once gel solidifies, re- seal the microwells with thin-film strips. The biochip is now ready to run the assay.
VenaT4 Biochip Protocol #2: trans endothelial migration assays under shear flow with VenaT4 biochips (single channel version)
Step 1:
Suspension cells (e.g. T cells) are re- suspended in culture medium at an appropriate concentration (typically 5 x 106/mL) in an Eppendorf tube. Cells are stained with a suitable dye.
Step 2:
Using the Cellix Mirus Evo nanopump or the ExiGo pump, 30 μL of media is dispensed from pump output cable. Following this, the output cable is inserted into a specified channel on the VenaT4 biochip.
Step 3:
Then using the Cellix Mirus Evo nanopump, or the ExiGo pump, 40 μL of the media is injected through the channel at a shear stress of 40 dynes/cm2. This is done to wash the channel. The waste is aspirated from the microwell of VenaT4 biochip with a pipette.
Step 4:
Cell sample is placed into the microwell of this channel on the VenaT4 biochip.
Step 5:
Cells are introduced into the channel, by specifying the desired shear stress using VenaFlux Assay software or SmartFlo application. The flow rate will be automatically calculated.
Step 6:
Time-lapse fluorescent images are recorded as the microscope objective is positioned over the microwell. The rate of image capture is 6 frames per minute for 30 minutes.
So now you know the features and benefits of our Vena T4 Biochip and how they works. But, if you still have questions or want to learn more, check out our website, at wearecellix.com, or contact us at info@wearecellix.com.