Safety of dimethylsulphoxide

Cryopreservation in 95% serum with 5% DMSO maintains colony formation and chondrogenic abilities in human synovial mesenchymal stem cells

Background

Synovial mesenchymal stem cells (MSCs) are an attractive cell source for cartilage and meniscus regeneration. The optimum cryopreservation medium has not been determined, but dimethylsulfoxide (DMSO) should be excluded, if possible, because of its toxicity. The purposes of our study were to examine the possible benefits of higher concentrations of serum and the effectiveness of 100% serum (without DMSO) for the cryopreservation of synovial MSCs.

Methods

Human synovium was harvested from the knees of four donors with osteoarthritis during total knee arthroplasty. Synovial MSCs (8 × 10⁵ cells) were suspended in 400 μL medium and used as a Time 0 control. The same number of synovial MSCs was also suspended in 400 μL α-MEM medium containing 10% fetal bovine serum (FBS) (5% DMSO, and 1% antibiotic), 95% FBS (and 5% DMSO), or 100% FBS (no DMSO) and cryopreserved at − 80 °C for 7 days. After thawing, the cell suspensions (1.5 μL; 3 × 10³ cells) were cultured in 60 cm² dishes for 14 days for colony formation assays. Additional 62.5 μL samples of cell suspensions (1.25 × 10⁵ cells) were added to tubes and cultured for 21 days for chondrogenesis assays.

Results

Colony numbers were significantly higher in the Time 0 and 95% FBS groups than in the 10% FBS group (n = 24). Colony numbers were much lower in the 100% FBS group than in the other three groups. The cell numbers per dish reflected the colony numbers. Cartilage pellet weights were significantly heavier in the 95% FBS group than in the 10% FBS group, whereas no difference was observed between the Time 0 and the 95% FBS groups (n = 24). No cartilage pellets formed at all in the 100% FBS group.

Conclusion

Synovial MSCs cryopreserved in 95% FBS with 5% DMSO maintained their colony formation and chondrogenic abilities to the same levels as observed in the cells before cryopreservation. Synovial MSCs cryopreserved in 100% FBS lost their colony formation and chondrogenic abilities.

Electronic supplementary material

The online version of this article (10.1186/s12891-019-2700-3) contains supplementary material, which is available to authorized users.

Adoptive transfer of DMSO-induced regulatory T cells exhibits a similar preventive effect compared to an in vivo DMSO treatment for chemical-induced experimental encapsulating peritoneal sclerosis in mice

Encapsulating peritoneal sclerosis (EPS) is a severe complication of peritoneal dialysis (PD). This disease leads to intestinal obstruction with or without peritonitis. The imbalance between the populations of Th17 and regulatory T (Treg) cells (higher Th17 cells and lower Treg cells) is part of the pathogenesis of EPS formation. We demonstrated that dimethyl sulfoxide (DMSO) effectively inhibited autoimmune diabetes recurrence in the islet transplantation of NOD mice via the induction of the differentiation of Treg cells. In this study, we investigated the therapeutic potential of DMSO in the inhibition of EPS formation by a mouse model. Under DMSO treatment, the thickening of the parietal and visceral peritoneum was significantly reduced. The populations of CD4, CD8, and IFN-γ-producing CD4 and CD8 T cells were decreased. The populations of IL-4-producing CD4 T lymphocytes, IL-10-producing CD4 T lymphocytes, CD4 CD69 T lymphocytes and Treg lymphocytes were increased. The expression levels of the cytokines IFN-γ, IL-17a, TNF-α and IL-23, in ascites, were significantly decreased following the DMSO treatment. Furthermore, the differentiation of Treg cells was induced by DMSO from naïve CD4 T cells in vitro, and these cells were adoptively transferred into the EPS mice and significantly prevented EPS formation, exhibiting a comparable effect to the in vivo DMSO treatment. We also demonstrated that the differentiation of Treg cells by DMSO occurred via the activation of STAT5 by its epigenetic effect, without altering the PI3K-AKT-mTOR or Raf-ERK pathways. Our results demonstrated, for the first time, that in vivo DMSO treatment suppresses EPS formation in a mouse model. Furthermore, the adoptive transfer of Treg cells that were differentiated from naïve CD4 T cells by an in vitro DMSO treatment exhibited a similar effect to the in vivo DMSO treatment for the prevention of EPS formation.

Behavioural effects of dimethyl sulfoxide (DMSO): changes in sleep architecture in rats

Dimethyl sulfoxide (DMSO) is an efficient solvent for water-insoluble compounds, widely used in biological studies and as a vehicle for drug therapy, but few data on its neurotoxic or behavioural effects is available. The aim of this work is to explore DMSO's effects upon sleep/wake states. Twenty male rats were sterotaxically prepared for polysomnography. Four concentrations of DMSO (5%, 10%, 15%, and 20%, in saline) were examined. DMSO or saline were administered intraperitoneally at the beginning of the light period. Three hours of polygraphic recording were evaluated for stages of vigilance after treatment. Sleep/wake parameters and EEG power spectral analyses during sleep were investigated. Results show no significant effect after 5% or 10% DMSO treatment. DMSO 15% increased mean episode duration of light slow wave sleep (SWS), decreasing mean episode duration of deep SWS and of quiet wake (QW). DMSO 20% increased light SWS enhancing number of episodes, while decreased deep SWS mean episode duration. EEG power spectra of sigma and delta activity were also affected by DMSO. Therefore, DMSO at 15% and 20% affects sleep architecture in rats, increasing light SWS and reducing deep SWS. Being aware of DMSO behavioural effects seems important since experimental artefacts caused by DMSO can lead to the erroneous interpretation of results.

Cryopreservation of Stem Cells Using Trehalose: Evaluation of the Method Using a Human Hematopoietic Cell Line

While stem cell cryopreservation methods have been optimized using dimethylsulfoxide (DMSO), the established techniques are not optimal when applied to unfertilized human embryonic cells. In addition, important questions remain regarding the toxicity and characteristics of DMSO for treatment of stem cells for clinical use. The objective of this study was to establish an optimal method for cryopreservation of stem cells using low concentrations (0.2 M) of trehalose, a nontoxic disaccharide of glucose, which possesses excellent protective characteristics, in place of current methods utilizing high concentrations (1-2 M) of DMSO. A human hematopoietic cell line was used in this investigation as a surrogate for human stem cells. Trehalose was loaded into cells using a genetically engineered mutant of the pore-forming protein alpha-hemolysin from Staphylococcus aureus. This method results in a nonselective pore equipped with a metal-actuated switch that is sensitive to extracellular zinc concentrations, thus permitting controlled loading of trehalose. Preliminary experiments characterized the effects of poration on TF-1 cells and established optimal conditions for trehalose loading and cell survival. TF-1 cells were frozen at 1 degrees C/min to -80 degrees C with and without intra- and extracellular trehalose. Following storage at -80 degrees C for 1 week, cells were thawed and evaluated for viability, differentiation capacity, and clonogenic activity in comparison to cells frozen with DMSO. Predictably, cells frozen without any protective agent did not survive freezing. Colony-forming units (CFU) generated from cells frozen with intra- and extracellular trehalose, however, were comparable in size, morphology, and number to those generated by cells frozen in DMSO. There was no observable alteration in phenotypic markers of differentiation in either trehalose- or DMSO-treated cells. These data demonstrate that low concentrations of trehalose can protect hematopoietic progenitors from freezing injury and support the concept that trehalose may be useful for freezing embryonic stem cells and other primitive stem cells for therapeutic and investigational use.

Multidisciplinary utilization of dimethyl sulfoxide: pharmacological, cellular, and molecular aspects

DMSO is an amphipathic molecule with a highly polar domain and two apolar methyl groups, making it soluble in both aqueous and organic media. It is one of the most common solvents for the in vivo administration of several water-insoluble substances. Despite being frequently used as a solvent in biological studies and as a vehicle for drug therapy, the side-effects of DMSO (undesirable for these purposes) are apparent from its utilization in the laboratory (both in vivo and in vitro) and in clinical settings. DMSO is a hydrogen-bound disrupter, cell-differentiating agent, hydroxyl radical scavenger, intercellular electrical uncoupler, intracellular low-density lipoprotein-derived cholesterol mobilizing agent, cryoprotectant, solubilizing agent used in sample preparation for electron microscopy, antidote to the extravasation of vesicant anticancer agents, and topical analgesic. Additionally, it is used in the treatment of brain edema, amyloidosis, interstitial cystitis, and schizophrenia. Several systemic side-effects from the use of DMSO have been reported, namely nausea, vomiting, diarrhea, hemolysis, rashes, renal failure, hypertension, bradycardia, heart block, pulmonary edema, cardiac arrest, and bronchospasm. Looking at the multitude of effects of DMSO brought to light by these studies, it is easily understood how many researchers working with DMSO (or studying one of its specific effects) might not be fully aware of the experiences of other groups who are working with it but in a different context.

Intensified chemotherapy supported by DMSO-free peripheral blood progenitor cells in breast cancer patients

BACKGROUND

The majority of high-dose chemotherapy (HDC)-related complications results from bone marrow aplasia, but the graft infusion per se may cause adverse reactions due to the injection of both dimethyl sulfoxide (DMSO) and cell lysis products. We evaluated the feasibility of a two-step chemotherapy regimen with peripheral blood progenitor cell (PBPC) support in association with a novel procedure to remove DMSO and products of cell lysis from the cryopreserved cells.

PATIENTS AND METHODS

Stage III and IV breast cancer patients received induction chemotherapy with three cycles of CEF (cyclophosphamide 600 mg/m2, epirubicin 100 mg/m2, 5-fluorouracil 600 mg/m2) followed by three cycles of HDC consisting of escalating doses of cyclophosphamide (dose range 1200 3000 mg/m2) and carboplatin (dose range 600-1000 mg/m2), supported by DMSO-free PBPC reinfusion. DMSO was removed by a washing/enzymatic digestion procedure.

RESULTS

Twenty patients received induction chemotherapy and eighteen completed the entire chemotherapy program; a total of fifty-four cycles of HDC were administered. Dose limiting toxicity of HDC was long-lasting grade 4 neutropenia associated with documented infection. The maximum tolerated dose (MTD) was cyclophosphamide 3000 mg/m2 and carboplatin 600 mg/m2. No side effects related to PBPC reinfusion were observed.

CONCLUSIONS

The proposed two-step chemotherapy regimen, associated with a novel washing/enzymatic digestion procedure, is feasible in advanced breast cancer patients in the absence of complications related to the specific toxicity of PBPC reinfusion.

A Prospective Randomized Trial of Buffy Coat Versus CD34-Selected Autologous Bone Marrow Support in High-Risk Breast Cancer Patients Receiving High-Dose Chemotherapy

High-dose chemotherapy with hematopoietic progenitor cell support is administered increasingly to selected categories of patients with high-risk malignancies. Bone marrow and/or peripheral blood progenitor cells (PBPCs) are commonly cryopreserved with the cryoprotectant dimethyl sulfoxide (DMSO), which can cause a variety of systemic side effects when the graft is thawed and infused. The progenitor cells thought to be responsible for hematopoietic recovery express the CD34 antigen and constitute 1% to 3% of the marrow cells and 0.5% of the PBPC fraction. Transplantation of a CD34+ graft would markedly reduce the volume and thus the amount of DMSO required, thereby decreasing the infusion-related toxicities. In this study, 89 high-risk breast cancer patients received high-dose therapy and were randomized to receive an autologous CD34+ marrow graft (Arm A) versus a standard buffy coat fraction (Arm B). After marrow infusion, significant increases in diastolic and systolic blood pressure, as well as significant decreases in heart rate, were documented in Arm B compared to Arm A patients (P < .001). None of the patients in Arm A experienced any clinically serious adverse events associated with the marrow infusion compared to 6% of the Arm B patients. The median time to neutrophil engraftment was 13 days for Arm A and 11 days for Arm B patients (P = .218). The median time to platelet engraftment was 27 days for Arm A and 20 days for Arm B patients (0.051). There were no other significant differences between the two arms of the study with respect to thrombocytopenia-related complications or immune function reconstitution. Additionally, patients on Arm A who received ≥1.2 × 106 CD34+ cells/kg had no delay in platelet recovery (22 days), compared to patients on Arm B, who also received greater than 1.2 × 106 CD34+ cells/kg (20 days) (P = .604). In conclusion, this prospective randomized study demonstrates that breast cancer patients who receive high-dose therapy with autologous CD34+ marrow support have reduced marrow infusion-related toxicity, comparable time to neutrophil engraftment and immune function recovery posttransplant, and for those who receive <1.2 × 106 CD34+ cells/kg, comparable time to platelet engraftment compared to women who receive buffy coat fractions of marrow.

A Prospective Randomized Trial of Buffy Coat Versus CD34-Selected Autologous Bone Marrow Support in High-Risk Breast Cancer Patients Receiving High-Dose Chemotherapy

High-dose chemotherapy with hematopoietic progenitor cell support is administered increasingly to selected categories of patients with high-risk malignancies. Bone marrow and/or peripheral blood progenitor cells (PBPCs) are commonly cryopreserved with the cryoprotectant dimethyl sulfoxide (DMSO), which can cause a variety of systemic side effects when the graft is thawed and infused. The progenitor cells thought to be responsible for hematopoietic recovery express the CD34 antigen and constitute 1% to 3% of the marrow cells and 0.5% of the PBPC fraction. Transplantation of a CD34+ graft would markedly reduce the volume and thus the amount of DMSO required, thereby decreasing the infusion-related toxicities. In this study, 89 high-risk breast cancer patients received high-dose therapy and were randomized to receive an autologous CD34+ marrow graft (Arm A) versus a standard buffy coat fraction (Arm B). After marrow infusion, significant increases in diastolic and systolic blood pressure, as well as significant decreases in heart rate, were documented in Arm B compared to Arm A patients (P < .001). None of the patients in Arm A experienced any clinically serious adverse events associated with the marrow infusion compared to 6% of the Arm B patients. The median time to neutrophil engraftment was 13 days for Arm A and 11 days for Arm B patients (P = .218). The median time to platelet engraftment was 27 days for Arm A and 20 days for Arm B patients (0.051). There were no other significant differences between the two arms of the study with respect to thrombocytopenia-related complications or immune function reconstitution. Additionally, patients on Arm A who received ≥1.2 × 106 CD34+ cells/kg had no delay in platelet recovery (22 days), compared to patients on Arm B, who also received greater than 1.2 × 106 CD34+ cells/kg (20 days) (P = .604). In conclusion, this prospective randomized study demonstrates that breast cancer patients who receive high-dose therapy with autologous CD34+ marrow support have reduced marrow infusion-related toxicity, comparable time to neutrophil engraftment and immune function recovery posttransplant, and for those who receive <1.2 × 106 CD34+ cells/kg, comparable time to platelet engraftment compared to women who receive buffy coat fractions of marrow.

Transplantation of CD34+ hematopoietic progenitor cells

We have developed an avidin-biotin immunoadsorption technique in conjunction with a monoclonal anti-CD34 antibody that is capable of selecting CD34+ progenitor cells from marrow and mobilized peripheral blood. Clinical studies with these CD34+ selected cells have shown that the cells are capable of rapid and durable engraftment. In addition, there is significantly less infusional toxicity to the patient because the volume in which the CD34+ selected cells are contained is much less than that of a typical marrow or apheresis buffy coat. Selection of CD34+ progenitor cells also offers other potential advantages, including T-cell depletion of allografts and tumor cell depletion of autografts. CD34+ selection can also be used to facilitate other manipulations of marrow and peripheral blood, including gene transfection, ex vivo stem cell expansion, tumor purging, and progenitor cell banking. Future graft engineering studies are expected to clarify these relationships and enable refinement of the graft to the point at which GVHD can be minimized, graft survival maximized, and relapse-free survival prolonged.

ACP Broadsheet No 134: December 1992. How to harvest bone marrow for transplantation

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Density gradient isolation of peripheral blood mononuclear cells using a blood cell processor

Large numbers of mononuclear cells (MNC) are needed for hematologic reconstitution using peripheral blood stem cells. The possibility of isolating those cells by discontinuous Ficoll-diatrizoate density gradient centrifugation in two blood cell processors (the Haemonetics V50 [V50] and the Cobe 2991 [2991]) were examined. Buffy coats from peripheral blood containing 6.23 X 10(8) MNC were separated in the V50, resulting in a recovery of 75 percent. The purity of the cells, defined as the percentage of lymphocytes and monocytes among all leukocytes, was 95 percent. With larger cell loads (3 to 7 X 10(9) MNC), the yield was higher in the V50 than in the Cobe 2991 (92 versus 75%). After separation in the V50 or the 2991, the cloning efficiencies of hematopoietic progenitor cells (CFU-GM and BFUe) were not different from those of cells isolated on 5 ml Ficoll-diatrizoate gradients in centrifuge tubes. Both leukapheresis and MNC separation can be carried out with the same bowl and tubing set in the V50. With that approach, an average of 6 X 10(9) MNC were processed in 16 experiments. An average recovery of 82 percent with 95 percent purity was achieved. The authors conclude that, in terms of simplicity of operation, cost effectiveness, and maintenance of sterility, the V50 may be better suited than the 2991 for the purification of MNC from peripheral blood.