Sandwich-achtige microenvironments Harness Cell / Material Interactions

The overall goal of this procedure is to assemble sandwich like cultures in order to study cell behavior within a more physiologically relevant 3D environment. This is accomplished by first preparing and coating the ventral and dorsal substrates with proteins such as fibronectin. Next, the cells are seated similar to a standard 2D culture.

Then the dorsal substrate is overlaid so that cells are ventrally and dorsally stimulated. Finally, experiments such as a wound healing assay can be carried out. Ultimately, sandwich like cultures are analyzed by procedures already developed for standard 2D cultures, such as live imaging, immunofluorescence, or cellular extraction.

For further analysis. The main advantage of this cultural technique over existing three-dimensional systems is that it allowed the study of different parameters in material interactions such as topography, chemistry, stiffness, and protein contents at both the ventral and dorsal sites offering a high degree of versatility. Besides experimental procedures that could be hindered for some three dimensional systems such as lipin, immunofluorescence, and cellular extractions are easily performed To produce a flat film of polylactic acid or PLLA by solvent casting working in a fume hood, add two grams of PLLA to 100 milliliters of chloroform and stir at room temperature for approximately three hours or until completely dissolved.

Place stainless steel washers on a glass petri dish. Then add 200 microliters of the PLLA solution into the washers. Use aluminum foil with a few holes to cover the dish and let the PLLA slowly evaporate at room temperature for 30 minutes.

Next, heat the samples at 120 degrees Celsius for five minutes in order to evaporate any traces of solvent. Then after allowing the samples to cool at room temperature for approximately 30 minutes, use 18.2 mega ohm centimeter water to cover the samples in the dish and incubate room temperature for eight minutes. After the incubation, use a razor blade to peel the washers off the Petri dish.

Then use tweezers to remove any imperfections from the edge of the washers and let the samples air dry. Because PLLA is degradable by hydrolysis store, the samples in a vacuum desiccate until the day of experiments. Additionally, ELLA fibers can be produced according to the text protocol and be used as a dorsal substrate under a sterile culture hood.

Add 20 micrograms per milliliter of FI nin in docos PBS or DPBS with calcium and magnesium to the samples and incubated room temperature for one hour following the protein coating. Use DPBS to wash the samples twice and store in DPBS with P calcium and magnesium until ready to use next seed cells on the glass cover slips and incubate at 37 degrees Celsius with 5%carbon dioxide for three hours to allow the cells to adhere to the ventral substrate. Then transfer the samples to new wells of a 12 well plate.

Using tweezers, carefully overlay the dorsal substrate on the cells. Then add one milliliter of medium. The weight of the washer will prevent the dorsal substrate from floating.

Return the samples to 37 degrees Celsius with 5%carbon dioxide, changing the medium twice per week to study cell migration within the sandwich like culture. After coating the ventral and dorsal substrates with fibronectin as demonstrated earlier, seed cells on glass cover slips at high density, incubate the samples and allow the cells to achieve confluence. Next, use a pipette tip to scratch the cell monolayer in order to create two cell populations separated by a gap.

Place the ventral seated substrate in a new well suitable for the time-lapse acquisition and large enough for dorsal substrates to fit inside. Then with tweezers as previously demonstrated, overlay the dorsal substrate on the cells and refill with medium. Place the sample under a time lapse microscope and capture images of the gap closure every 20 minutes.

Use software such as mito BO from Image J to analyze the gap closure in the sandwich. Like culture. Sulfate is highly dependent on the time when the dorsal receptors are stimulated and by the properties of the dorsal interaction.

Similar to other 3D systems such as hydrogels, for example, as seen here, dorsal electro spun PLLA fibers direct cell alignment when coated with fibronectin, but not when coated with a non-adhesive protein like BSA. Additionally, sandwich like cultures with plain dorsal PLLA triggered an increase in the level of myogenesis using C two C 12 cells. This also depends on the dorsal biological stimuli.

Since the interaction with different dorsal proteins results in distinct differentiation rates as demonstrated in this video, fibroblasts migrating within the sandwich like culture in a wound healing assay, adopt an elongated morphology and migrate shorter distances compared to cells. Cultured on 2D substrates similar to 3D fibronectin and collagen gels. Sandwich like culturing increases cell mediated ECM reorganization compared to 2D conditions.

This process relies on the dorsal mechanical stimuli and cytoskeleton stability. Since the use of contractility inhibitors such as BLEs, statin hindered the process S Okay, so after watching this video, you should have a clear understanding of how to assemble sandwich like cultures. This method can engineer 3D like microenvironment for react medicine and cancer, including applications in disease models, development studies, and drug testing.