MDM culture
Arpine Sokratian, enquan.xu
Abstract
This protocol details the steps for isolation of PBMC from donors’ buffy coat and differentiation protocol into MDM cells. We use this MDM model to investigate the immune cellular uptake and proinflammatory response upon treatment with alpha-synuclein fibrils.
Steps
Use the buffy coat transported from Red blood cross center (On ice
, ).
Dilute blood with an equal amount of
Transfer the blood on top of Lymphoprep™
Centrifuge at 1200 x g for 0h 20m 0s
Room temperature
(15 - 25°C), with the brake on. If the blood has been stored for more than 2 hours, increase the centrifugation time to 0h 30m 0s
.
Pour off the top layer, which contains the enriched MNCs, into a new tube. Do not hold the SepMate™ tube in the inverted position for longer than 2 seconds.
Wash enriched PBMCs with PBS + 2% FBS. Repeat wash with 400x g,0h 0m 0s
for 10 minutes at room temperature.
Prepare the PBMCs at the 5 x 10^7 cells/ml within the 1mL
of PBS + 2% FBS buffer.
Add the sample to the 5mL
Add enrichment Cocktail to sample at 50 ul/ml from the EasySep™ Human Monocyte Enrichment Kit without CD16 Depletion
Incubate On ice
for 0h 10m 0s
Add 50µL
mag beads buffer (from STEMCELL TECH KIT, make sure you VORTEX the mag beads buffer 30 secs before taking50µL
out!!!) and pipet up and down for no more than 5 times (enough to see the beads mixed all well (determined by the color).
Incubate the mix in the refrigerator or on the ice for 0h 5m 0s
Transfer the mix into either sterile flow tube or 15 ml canonical tube (depend on which mag selection set you would use. If you want to use the single mag set, then you have to use sterile flow tube. The multiple
channel mag set would allow you to choose between flow tube or 15 ml canonical tube.
Add the selection buffer up to 2.5 ml (For flow tubes, add 2.5 mL PBS or up to 2.5 mL marker on the tube).
Hold the tube (if you use the multiple channel mag set) and pour the mix buffer out into the new collection tube (15 ml canonical tube) in a continuous manner (don’t let the mix buffer back flow to contact the mag
beads trapped by the mag set on the tube wall). Don’t try to drip out the last drop of the buffer. You would rather wash twice instead of shaking of the beads to contaminate your final yield.
Add another 2.5 ml of selection buffer and repeat the steps listed above. Take 10 ul to mix with 90 ul of typan blue in PBS for cell counting (formula here: Total cells you count in four chamber/4x10x5x104 =total cells number in 5 ml buffer).
Centrifuge at 400x g,0h 0m 0s
, 0h 15m 0s
, Room temperature
, with full break and remove the selection buffer supernatant thoroughly (to remove EDTA) and resuspend with DMEM+10%FBS+1XGlutmax+ 1X Antianti+20 ng/ml human recombinant MCSF (1000x; stock should stored at-80 C). All the cytokines are from PeproTech and should be dissolved in stock 1000x except CCL2 and IL34 (100x).
Seed the cells into the cell culture plates (2.5 X 105/well for 24-well plate with 1 ml of cell culture medium
Incubate the cell culture in CO2 cell incubator. At day 3 add 0.5 mL additional medium containing MCSF to cell culture.
MDM should be ready to use at day 7 (the cell maturation different from patient to patient, 7 days will be a safe place to use. For most of patients, if the MDM cells still don’t grow well up to 10 days, it won’t.)
Don’t let the MDM grow more than 12 days (or the media will become yellow)