To begin, place the 15 milliliter tube containing prewarmed enzymatic cell digestion reagent in a 37 degree Celsius incubator until use. Aliquot 500 microliters of freshly prepared PBS/EDTA into the wells of a 24 well plate. Under a brightfield microscope, observe the growth of differentiated three dimensional human intestinal organoids and transwells.
Transfer the cell culture inserts from the growth media to the PBS/EDTA solution. Remove the culture media from the apical side and replace it with 100 microliters of PBS/EDTA without disturbing the cell layer. After discarding PBS/EDTA, remove the insert from the well, blot it gently onto the edge of a paper towel and inverted on the bench top.
Using a sharp scalpel blade, cut around the inner circumference of the membrane to remove the membrane from the insert. Transfer the membrane with forceps to the 1.5 milliliter tube containing 200 microliters of prewarmed enzymatic cell digestion reagent. Place the membrane for 30 minutes at 37 degrees Celsius in a carbon dioxide incubator.
Every 10 minutes, pipette the entire volume five times using a P 200 pipette. Transfer, one to two microliters of cell suspension to a glass slide every 10 minutes to assess dissociation by qualitatively assessing the percentage of single cells. After dissociation, combine three replicate wells per condition in a single 1.5 milliliter micro centrifuge tube.
Add 400 microliters of cell culture differentiation medium containing 10 micromolar ROCK inhibitor and mix gently by pipetting. Filter the entire volume through a 70 micron tip strainer, collecting the flowthrough in a fresh 1.5 milliliter tube. Then filter the flowthrough obtained through a 70 micron strainer on a 40 micron tip strainer.
Add five microliters of 0.4%trypan blue to five microliters of cell suspension and count viable single cells. Dilute the sample with WRNE growth medium to obtain 1, 000 cells per microliter. A total of 5, 623 single cells were isolated from differentiated jejunal human intestinal organoids grown on membrane cell culture inserts.