Evaluation of methylcellulose and dimethyl sulfoxide as the cryoprotectants in a serum-free freezing media for cryopreservation of adipose-derived adult stem cells.
Developing effective techniques for the cryopreservation of human adipose-derived adult stem cells (ASCs) could increase the usefulness of these cells in tissue engineering and regenerative medicine. To this end, we investigated the post-freeze/thaw viability and apoptotic behavior of Passage 1 (P1) adult stem cells (ASCs) in 11 different media: (i) the traditional media containing Dulbecco's modified Eagle's medium (DMEM) with 80% fetal calf serum (FCS) and 10% dimethyl sulfoxide (DMSO), (ii) DMEM with 80% human serum (HS) and 10% DMSO, (iii) DMEM with 1% methyl cellulose (MC) and 10% of either HS or FCS or DMSO, and (iv) DMEM with 0%, 2%, 4%, 6%, 8%, or 10% DMSO. Approximately 1 mL (10(6) cells/mL) of P1 ASCs were frozen overnight in a -80 degrees C freezer and stored in liquid nitrogen for 2 weeks before being rapidly thawed in a 37 degrees C water bath (1-2 min of agitation), resuspended in culture media, and seeded in separate wells of a 6-well plate for a 24-h incubation period at 37 degrees C. After 24 h, the thawed samples were analyzed by bright-field microscopy and flow cytometry. The results suggest that the absence of DMSO (and the presence of MC) significantly increases the fraction of apoptotic and/or necrotic ASCs. However, the percentage of viable cells obtained with 2% DMSO and DMEM was comparable with that obtained in freezing media with 10% DMSO and 80% serum (HS or FCS), that is, approximately 84% +/- 5% and approximately 84% +/- 8%, respectively. Adipogenic and osteogenic differentiation behavior of the frozen thawed cells was also assessed using histochemical staining. Our results suggest that post-thaw ASC viability, adipogenic and osteogenic differentiability can be maintained even when they are frozen in the absence of serum but with a minimal concentration of 2% DMSO in DMEM.
Bioengineering Laboratory, Department of Mechanical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
Sreedhar
S
Thirumala
Jeffrey M
JM
Gimble
Ram V
RV
Devireddy
D052438:Adipocytes, White / Q000166:cytology; D053687:Adult Stem Cells / Q000166:cytology; D017209:Apoptosis; D002454:Cell Differentiation; D002469:Cell Separation; D002470:Cell Survival; D002478:Cells, Cultured; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents; D016895:Culture Media, Serum-Free; D004121:Dimethyl Sulfoxide; D006801:Humans; D008747:Methylcellulose; D009336:Necrosis; D010011:Osteocytes / Q000166:cytology*
D003451:Cryoprotective Agents; D016895:Culture Media, Serum-Free; D008747:Methylcellulose; D004121:Dimethyl Sulfoxide