DMSO: An effective cryoprotectant with several safety issues

The traditional compound for cryopreservation has for decades been dimethyl sulfoxide. This organic solvent, even though well-known to most in the cryopreservation area, has a number of short-comings:

  • Reports of severe adverse reactions, such as cardiac or respiratory arrest, neurotoxicity and epileptic seizures 1

    • From the USP: DMSO is associated with risk of predictable dose-dependent gastrointestinal, cardiovascular, and neurologic toxicities that typically are ascribed to histamine release 2

  • Changes in the cellular epigenetic state

    • DMSO shown to induce hydroxymethylation (5hmC)  and reduce methylation (5mC) in pre-osteoblastic MC3T3-E1 cells 2

    • Increase expression and activity of de novo methyltransferase 3

    • Directly cause methylation of cytosine 4

  • Strong and unpleasant smell which is a nuisance for staff, patients, and their surroundings

    • From the USP: DMSO is categorized by ICH as a Class 3 (relatively low risk) solvent or excipient in pharmaceutical products, and amounts of up to 50 mg/day, or less, are considered acceptable without justification (see ICH Q3C) 2 Cryopreserved cellular products frequently contain 10–20 times this amount unless they are washed after thawing.

  • Requests from regulators for alternatives 5

1. Gao d. et al. Bone Marrow Transplant. 2014 Apr;49(4):469-76      
2. From the USP 38 <1044> "Cryopreservation of cells" (p. 827)         
3. Kung A.W.C et al. FEBS Lett. 2006 Jan 9;580(1):121-6
4. Robertson K.D. et al. Bioorg Chem. 2004 Aug;32(4):234-43
5. Kasai H. et al. Bioorg Med Chem Lett. 2010 Jan 1;20(1):260-5
6. Cox M.A., et al. Cell Tiss Bank, 2012, 13(2):203-15



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