- Dimethyl sulfoxide (DMSO) is a widely used chemical compound in stem cell research, valued primarily for its ability to preserve cells during cryopreservation.
- Its amphipathic nature allows it to penetrate biological membranes and interact with both hydrophilic and hydrophobic molecules.
- The most common application of DMSO in this field is as a cryoprotectant. When stem cells are frozen for long-term storage, ice crystal formation can damage cellular structures. DMSO prevents this by inhibiting crystallization and protecting cell membranes, thereby maintaining cell viability. Typically, a concentration of 5–10% DMSO is used in a cryopreservation medium that may also contain serum or serum substitutes. However, since DMSO is cytotoxic at room temperature, it must be rapidly diluted and removed after thawing to prevent damage to the cells.
- Beyond its role in cell preservation, DMSO also influences stem cell differentiation. At low concentrations, it can act as a modulator of cell fate, particularly in embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). Studies have shown that DMSO can promote differentiation toward specific lineages, such as endodermal or mesodermal, by affecting signaling pathways and cell cycle dynamics. This effect is partly due to DMSO’s impact on epigenetic regulation, including changes in DNA methylation and histone modification, which are critical in determining gene expression patterns during stem cell differentiation.
- DMSO is also commonly used as a solvent in stem cell research, especially for dissolving small molecules and hydrophobic drugs in experimental assays. Its strong solvating power allows it to deliver various compounds into cells. However, even trace amounts of DMSO can influence cell physiology, including viability, morphology, and gene expression. Therefore, it is essential to include proper solvent controls in experiments to distinguish the effects of the test compound from those of DMSO itself.
- Despite its versatility, DMSO is not without drawbacks. Its cytotoxicity is a major concern, especially in clinical applications where residual DMSO can affect patient safety. Additionally, its capacity to alter gene expression and epigenetic landscapes raises concerns about data interpretation, particularly in studies focusing on developmental biology or regenerative medicine. Pharmaceutical-grade DMSO is recommended for use in sensitive applications to minimize variability and the presence of impurities.
- Due to these concerns, researchers are exploring alternatives to DMSO-based cryopreservation. Substances such as glycerol, ethylene glycol, and trehalose, as well as commercial DMSO-free cryopreservation solutions, offer varying degrees of success in maintaining cell viability without the associated risks of DMSO. Innovations in freezing protocols, such as controlled-rate freezing and optimized thawing procedures, further enhance the efficiency of cell preservation while minimizing the need for high DMSO concentrations.
