title: Magnetic cryopreservation for dental pulp stem cells.
abstract: Magnetic cryopreservation has been successfully used for tooth banking with satisfactory implantation outcomes, suggesting that the method preserves human periodontal ligament cells and dental pulp stem cells (DPSCs). Therefore, magnetic cryopreservation may be applied for the preservation of DPSCs; however, this method has not been evaluated yet. A reliable cryopreservation method for live-cell preservation is important for the clinical applications of regenerative medicine. The conventional slow-freezing procedure with 10% dimethylsulfoxide (DMSO) may not be appropriate for stem cell-based therapies because DMSO is cytotoxic. The objective of this study was to investigate whether magnetic cryopreservation can be applied for DPSC cryopreservation. Cells isolated from human dental pulp were subjected to magnetic cryopreservation. Postthawing cell viability, adhesion, proliferation, expression of markers for mesenchymal stem cells (MSCs), differentiation ability of magnetically cryopreserved DPSCs and DNA stability were compared to those of cells subjected to the conventional slow-freezing method. The results indicated that a serum-free cryopreservation medium (SFM) containing 3% DMSO is optimal for magnetic cryopreservation. Post-thaw magnetically cryopreserved DPSCs express MSC markers, and perform osteogenesis and adipogenesis after induction similarly to fresh MSCs. No significant DNA damage was found in magnetically cryopreserved DPSCs. Magnetic cryopreservation is thus a reliable and effective method for storage of DPSCs. The smaller amount of DMSO required in SFM for cryopreservation is beneficial for the clinical applications of post-thaw cells in regenerative medicine.
authors.affiliation: School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Sheng-Yang
authors.initials: SY
authors.lastname: Lee
authors.forename: Guo-Wei
authors.initials: GW
authors.lastname: Huang
authors.forename: Jau-Nan
authors.initials: JN
authors.lastname: Shiung
authors.forename: Yen-Hua
authors.initials: YH
authors.lastname: Huang
authors.forename: Jiiang-Huei
authors.initials: JH
authors.lastname: Jeng
authors.forename: Tzong-Fu
authors.initials: TF
authors.lastname: Kuo
authors.forename: Jen-Chang
authors.initials: JC
authors.lastname: Yang
authors.forename: Wei-Chung Vivian
authors.initials: WC
authors.lastname: Yang
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000187:drug effects; D015415:Biomarkers / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004247:DNA / Q000378:metabolism; D004249:DNA Damage; D003782:Dental Pulp / Q000166:cytology*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D005260:Female; D005615:Freezing; D006801:Humans; D008280:Magnetics / Q000379:methods*; D008297:Male; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism
chemical_list: D015415:Biomarkers; D003451:Cryoprotective Agents; D004247:DNA; D004121:Dimethyl Sulfoxide