Cryopreservation Of Cells Research Articles

Cryopreservation of Stem Cell-Derived β-Like Cells Enriches for Insulin-Producing Cells With Improved Function.

The generation of stem cell-derived beta-like cells (sBC) holds extreme promise as not only an abundant insulin-producing cell source for replacement therapy of Type 1 diabetes (T1D), but also as an invaluable model system for investigating human beta cell development, immunogenicity, and function. Several groups have developed methodology to direct differentiate human pluripotent stem cells into pancreatic cell populations that include glucose responsive sBC. Nevertheless, the process of generating sBC poses significant experimental challenges. It involves lengthy differentiation periods, experiences substantial variability in efficiency, and inconsistencies in obtaining functional sBC. Here, we described a simple and effective cryopreservation approach for sBC cultures that yields homogeneous sBC clusters that are enriched for insulin expressing cells while simultaneous depleting proliferative progenitors. Thawed sBC display enhanced glucose-stimulated insulin release compared to controls in vitro and can effectively engraft and function in vivo. Collectively, this approach alleviates current challenges with inefficient and variable sBC generation while improving their functional state. We anticipate that these findings can inform ongoing clinical application of sBC for the treatment of patients with T1D and serve as an important resource for the wider diabetes field that will allow for accelerated research discoveries.

L-Proline and GelMA hydrogel complex：An efficient antifreeze system for cell cryopreservation

Cryopreservation of biological samples is an important technology for expanding their applications in the biomedical field. However, the quality and functionality of samples after rewarming are limited by the toxicity of commonly used cryoprotectant agents (CPAs). Here, we developed a novel preservation system by combining the natural amino acid l-proline (L-Pro) with gelatin methacryloyl (GelMA) hydrogels. Compared with dimethyl sulfoxide (DMSO), L-Pro and GelMA demonstrated excellent biocompatibility when co-culturing with cells. Cryopreservation procedures were optimized using 3T3 as model cells. The results showed that rapid cooling was the most suitable cooling procedure for L-Pro and GelMA among the three cooling procedures. Co-culturing with cells for 3 h before cryopreservation, 6 % L-Pro +7 % GelMA had the highest survival rate, reaching up to 80 %. Differential Scanning Calorimetry (DSC) analysis showed that 6 % L-Pro + 7 % GelMA lowered the freezing point of the solution to −4.2 °C and increased the unfrozen water content to 20 %. To the best of our knowledge, this is the first report of cell cryopreservation using a combination of L-Pro and GelMA hydrogels, which provides a new strategy for improving cell cryopreservation.

Isolation and cryopreservation of Pseudopimelodus mangurus (Siluriformes) spermatogonial cells

Spermatogonia cryopreservation can be a strategy for future conservation actions. The neotropical Siluriformes Pseudopimelodus mangurus was already classified as vulnerable on the Red List of Threatened Species. P. mangurus spermatogonial cells were isolated, assessed, and cryopreserved. Fragments of the testis were enzymatically dissociated, purified using Percoll density gradient, and submitted to differential plating. Fractionated cells were evaluated by microscopy, ddx4 (vasa) relative expression, and alkaline phosphatase activity. Cryopreservation was conducted using ethylene glycol, glycerol, dimethyl sulfoxide (DMSO), dimethylacetamide (DMA), and propanediol at 1 M, 1.5 M, and 2 M. Cell viability was evaluated and cell concentration was determined. Cell fractions from 20 % and 30 % Percoll gradient bands showed the highest concentrations of spermatogonia. The fraction mix showed 54 % purity and 93 % viability. After differential plating, 60 % purity and 92 % viability were obtained. Spermatogonial cells showed high alkaline phosphatase activity compared to spermatocytes and spermatids. The relative spermatogonial ddx4 expression from the Percoll density gradient was about twice as high as in samples from the testis and the differential plating. The increased ddx4 expression indicated the enrichment of spermatogonial cells by density gradient step and dead cells expressing ddx4 in differential plating, or ddx4 decreasing expression during cell culture. For this reason, cells from the Percoll gradient were chosen for cryopreservation. Propanediol at 1 M demonstrated the best condition for spermatogonial cell cryopreservation, presenting 98 % viability, while dimethylacetamide at 2 M represented the least favorable condition, with approximately 47 % viability. These findings are essential for P. mangurus spermatogonial cell cryopreservation, aiming to generate a spermatogonia cryobank for future conservation efforts.

Cryopreservation of stem cell-derived beta-like cells enriches for insulin-producing cells with improved function.

The generation of stem cell-derived beta-like cells (sBC) holds extreme promise as not only an abundant insulin-producing cell source for replacement therapy of Type 1 diabetes (T1D), but also as an invaluable model system for investigating human beta cell development, immunogenicity, and function. Several groups have developed methodology to direct differentiate human pluripotent stem cells into pancreatic cell populations that include glucose responsive sBC. Nevertheless, the process of generating sBC poses significant experimental challenges. It involves lengthy differentiation periods, experiences substantial variability in efficiency, and inconsistencies in obtaining functional sBC. Here, we described a simple and effective cryopreservation approach for sBC cultures that yields homogeneous sBC clusters that are enriched for insulin expressing cells while simultaneous depleting proliferative progenitors. Thawed sBC display enhanced glucose-stimulated insulin release compared to controls in vitro and can effectively engraft and function in vivo. Collectively, this approach alleviates current challenges with inefficient and variable sBC generation while improving their functional state. We anticipate that these findings can inform ongoing clinical application of sBC for the treatment of patients with T1D and serve as an important resource for the wider diabetes field that will allow for accelerated research discoveries.

Cryopreservation and passaging optimization for Galea spixii (Wagler, 1831) adult skin fibroblast lines: A step forward in species management and genetic studies

BackgroundIn vitro culture of fibroblasts is a technique based on cell isolation, physiological characterization, and cryopreservation. This technique has not been described for Galea spixii, therefore, it can be used to learn about its cellular biology and genetic diversity. ObjectiveWe established fibroblast lines of six G. spixii individuals from several passages (second, fifth, eighth, and tenth) and cryopreserved them. MethodsFibroblasts recovered from skin biopsies were identified based on morphology, immunocytochemistry, and karyotyping. The cells were analyzed for morphology, ultrastructure, viability, proliferation, metabolism, oxidative stress, bioenergetic potential, and apoptosis before and after cryopreservation. ResultsAfter the eighth passage, the fibroblasts showed morphological and karyotypic changes, although their viability, metabolism, and proliferation did not change. An increase in oxidative stress and bioenergetic potential from the fifth to the eighth passages were also observed. Post cryopreservation, cell damage with respect to the ultrastructure, viability, proliferative rate, apoptotic levels, oxidative stress, and bioenergetic potential were verified. ConclusionFibroblasts up to the tenth passage could be cultured in vitro. However, cells at the fifth passage were of better quality to be used for reproductive techniques. Additionally, optimization of the cryopreservation protocol is essential to improve the physiological parameters of these cells.

Cryoprotective effects of deicing micro/nanomaterials with different sizes and shapes on cells

Extensive studies have been conducted on deicing nanomaterials to improve the cryoprotective effects on cells, tissues, and organs. The nanomaterials with different composition, sizes, and shapes can inhibit the formation and growth of ice crystals, thereby reducing the damage to the cryopreserved samples. In this study, the carbon composite particles (CCPs) with different sizes and shapes were prepared by the hydrothermal method. The results demonstrated that the cryoprotective effect of CCPs enhanced with the decrease in particle size. Compared with spherical CCPs, Janus nanoparticles and WSP nanoflower with special shapes demonstrated improved protective effects on cryopreserved cells. In addition, the combination of deicing micro/nanomaterials at appropriate concentrations with commercial cryoprotectants exerted improved cryoprotective effects on cells. The prepared deicing micro/nanomaterials can improve cell cryopreservation, demonstrating great application potential in biomedical research and cryopreservation.

Development of Macromolecular Cryoprotectants for Cryopreservation of Cells.

Cryopreservation is a common way for long-term storage of therapeutical proteins, erythrocytes, and mammalian cells. For cryoprotection of these biosamples to keep their structural integrity and biological activities, it is essential to incorporate highly efficient cryoprotectants. Currently, permeable small molecular cryoprotectants such as glycerol and dimethyl sulfoxide dominate in cryostorage applications, but they are harmful to cells and human health. As acting in the extracellular space, membrane-impermeable macromolecular cryoprotectants, which exert remarkable membrane stabilization against cryo-injury and are easily removed post-thaw, are promising candidates with biocompatibility and feasibility. Water-soluble hydroxyl-containing polymers such as poly(vinyl alcohol) and polyol-based polymers are potent ice recrystallization inhibitors, while polyampholytes, polyzwitterions, and bio-inspired (glyco)polypeptides can significantly increase post-thaw recovery with reduced membrane damages. In this review, the synthetic macromolecular cryoprotectants are systematically summarized based on their synthesis routes, practical utilities, and cryoprotective mechanisms. It provides a valuable insight in development of highly efficient macromolecular cryoprotectants with valid ice recrystallization inhibition activity for highly efficient and safe cryopreservation of cells.

High interspecific variability in ice nucleation activity suggests pollen ice nucleators are incidental

Abstract. Ice-nucleating macromolecules (INMs) produced by plant pollen can nucleate ice at warm temperatures and may play an important role in weather- and climate-relevant cloud glaciation. INMs have also proved useful for mammalian cell and tissue model cryopreservation. The high ice nucleation (IN) activity of some INMs indicates an underlying biological function, either freezing tolerance or bioprecipitation-mediated dispersal. Here, using the largest study of pollen ice nucleation to date, we show that phylogenetic proximity, spermatophyte subdivision, primary growth biome, pollination season, primary pollination method, desiccation tolerance and native growth elevation do not account for the IN activity of INMs released from different plant species' pollen. The results suggest that these macromolecules are produced by plants for a purpose unrelated to ice nucleation and have an incidental ability to nucleate ice. This ability may have been adapted by some species for specific biological purposes, producing exceptional ice nucleators. Pollen INMs may be more active, widespread in nature, and diverse than previously thought.

Alternative cryoprotective agent for corneal stroma-derived mesenchymal stromal cells for clinical applications

Cryopreservation of human corneal stroma-derived mesenchymal stromal cells (hCS-MSCs) with dimethylsulfoxide (DMSO) as a cryoprotective agent (CPA) has not been previously compared to that with glycerol under standard conditions. The hCS-MSCs were hereby cryopreserved with both compounds using a freezing rate of 1 °C/minute. The CPAs were tested by different concentrations in complete Minimum Essential Medium (MEM) approved for good manufacturing practice, and a medium frequently used in cell laboratory culturing—Dulbecco’s modified eagle serum. The hCS-MSCs were isolated from cadaveric human corneas obtained from the Norwegian Eye Bank, and immunophenotypically characterized by flow cytometry before and after cryopreservation. The survival rate, the cellular adhesion, proliferation and cell surface coverage after cryopreservation of hCS-MSCs has been studied. The hCS-MSCs were immunofluorescent stained and examined for their morphology microscopically. The results showed that cryopreservation of hCS-MSCs in MEM with 10% glycerol gives a higher proliferation rate compared to other cryopreserving media tested. Based on the results, hCS-MSCs can safely be cryopreserved using glycerol instead of the traditional use of DMSO.

Evaluation of the effectiveness of the use of exosomes in the regulation of the mitochondrial membrane potential of frozen/thawed spermatozoa.

Numerous studies confirm the involvement of extracellular vesicles (EVs) in the regulation of physiological processes of mammalian sperm cells. It has been proven that they take part in the processes of capacitation, acrosonmal reaction, and anti-oxidation. Despite growing interest in the biomedical potential (including the search for new reproductive biomarkers) of EVs, the role of extracellular seminal vesicles in maintaining semen quality during cryopreservation has not yet been established. Therefore, the objective of this experiment was to evaluate the effectiveness of the use in the regulation of the mitochondrial membrane potential of bovine sperm and to explain the mechanisms of EV action during cell cryopreservation. Exosomes were isolated from bull semen plasma, measured, and used for extender supplementation. Semen samples were collected from Simmental bulls, diluted, and pre-evaluated. Then they were divided into equal fractions that did not contain EVs or were supplemented with 0.75; 1.5 and 2.25 mg/ml of EVs. The test samples were frozen/thawed and the mitochondrial membrane potential, DNA integrity, and viability were evaluated. EVs have been established to have a positive effect on cryopreserved sperm structures. The most favourable level of EVs was 1.5 mg / ml, which can be successfully to improve cell cryostability during freezing/thawing. In this study, exosomes isolated from the sperm plasma and supplemented with a concentrated dose in the extender for sperm freezing were shown to significantly improve cryostability of cells by supporting the potentials of the mitochondrial membrane and protecting the cytoplasmic membrane of spermatozoa.

O-282 Detection and elimination of malignant cells from cryopreserved testis and ovarian tissue?

Abstract For young patients receiving treatments that might impair their reproductive functions, gonadal tissue cryopreservation emerges as a technique to preserve their future fertility. The reimplantation of cryopreserved prepubertal gonadal tissue is currently the most promising strategy for restoring fertility in these individuals. There have been reports of successful births after autotransplanting ovarian tissue harvested at peri-puberty. In males, although autotransplantation of testicular tissue has not yet led to the production of viable sperm, successful reproduction has been documented in primate studies following such procedures. The preservation of gonadal tissue in the setting of cancer introduces concerns regarding the potential for malignant cell contamination, leading to worries about the future reimplantation of contaminated tissue. Recent analysis shows significant contamination rates with cancer cells in cryopreserved gonadal tissues from children with leukemia and lymphoma — 37% in testicular tissues and 12% in ovarian tissues. The risk of contamination extends beyond hematological cancers with documented cases of cancer cell contamination in ovarian tissue from patients with apparently localized sarcoma, and detection of neuroblastoma cells in cryopreserved testicular tissue. Such significant contamination rates prompt discussions about harvesting tissue post-chemotherapy, although gonadotoxic treatments may adversely affect the quality of the cryopreserved germ cells. Emerging diagnostic techniques, especially molecular methods, are being investigated for their ability to more accurately detect residual maliganat disease. While traditional histology and immunohistochemistry have been the norm, their sensitivity is relatively low. More precise molecular-genetic techniques, such as Polymerase Chain Reaction (PCR) and Reverse Transcriptase-quantitative PCR, demonstrate greater sensitivity. Moreover, advanced methods like next-generation sequencing offer even higher precision in detecting minimal residual disease. Xenotransplantation of gonadal tissue into immunodeficient animals may also provide some insights as a preclinical method for relapse prediction. Future research is essential to refine these diagnostic techniques to achieve the necessary sensitivity for clinical application. This presentation aims to explore the current knowledge on gonadal tissue contamination rates for both hematological cancers and solid tumors in prepubertal patients and to review strategies for decontaminating gonadal tissues. A critical examination of existing knowledge gaps will be conducted with the objective of identifying secure methods for fertility restoration in cancer survivors.

Monarch butterfly conservation through male germplasm cryopreservation

Monarch butterfly (Danaus plexippus L.) populations have declined in North America. The International Union for Conservation of Nature (IUCN) recently classified the species as endangered, sparking public concern and conservation efforts. Our approach to conservation is through cryopreservation of germinal cells and tissue. The goal of this study was to develop a cryopreservation protocol for monarch spermatozoa to ensure successful long-term storage. Cryopreserved sperm cells would provide a reserve of monarch germplasm, which could be utilized in the event of population loss. In this study, sperm cell bundles collected from male monarch butterflies were cryopreserved in a cryoprotective medium and stored in liquid nitrogen. To determine the post-cryopreservation sperm cell viability, a subsample of preserved sperm bundles were thawed rapidly, and their viability was qualified using a sperm live/dead stain. We are presenting a protocol to preserve and store genetic material and viable sperm bundles of the monarch butterfly. To date, this is the first report of successful cryopreservation of monarch germplasm which sets the foundation for cryostorage and could be extensible to other vulnerable lepidopterans.

Optimization of cryopreservation methods for somatic cells of the Tobet dog breed

The Tobet dog breed, a national heritage of Kazakhstan, is threatened with extinction and conservation measures are urgently needed. This study presents a pioneering approach to preserve the genetic diversity and survival of this endangered breed through cryopreservation and cryobanking. We have optimised methods for cryopreservation of somatic cells (fibroblasts) isolated from skin explants of Tobet dogs and investigated the effects of in vitro cultivation on cell viability. Our results emphasise the importance of selecting appropriate culture media and cryoprotectants. Dulbecco's Modified Eagle Medium (DMEM) and ethylene glycol (EG) were found to be the most effective agents for increasing the growth rate and viability of fibroblasts after thawing. Through careful experimentation, including the evaluation of equilibrium and non-equilibrium cryopreservation techniques and the application of various cryoprotectants, we have established the first Tobet cryobank for somatic cells. The establishment of a cryobank represents a significant step towards the conservation of the Tobet dog breed and provides a model for the conservation of other endangered species. This study not only contributes to the preservation of Kazakhstan's cultural and biological heritage, but also opens up new avenues for the application of biotechnological approaches to wildlife conservation.

Enhancing cell cryopreservation with acidic polyamino acids integrated liquid marbles

Cryopreservation is highly desired for long-term maintenance of the viability of living biosamples, while effective cell cryopreservation still relies heavily on the addition of dimethyl sulfoxide (DMSO) and fetal bovine serum (FBS). However, the intrinsic toxicity of DMSO is still a bottleneck, which could not only cause the clinical side effect but also induce cell genetic variants. In the meantime, the addition of FBS may bring potentially the risk of pathogenic microorganism contamination. The liquid marbles (LMs), a novel biotechnology tool for cell cryopreservation, which not only have a small volume system that facilitated recovery, but the hydrophobic shell also resisted the harm to cells caused by adverse environments. Previous LM-based cell cryopreservation relied heavily on the addition of FBS. In this work, we introduced acidic polyaspartic acid and polyglutamic acid as cryoprotectants to construct LM systems. LMs could burst in an instant to facilitate and achieve ultrarapid recovery process, and the hydrophilic carboxyl groups of the cryoprotectants could form hydrogen bonds with water molecules and further inhibit ice growth/formation to protect cells from cryoinjuries. The L929 cells could be well cryopreserved by acidic polyamino acid-based LMs. This new biotechnology platform is expected to be widely used for cell cryopreservation, which has the potential to propel LMs for the preservation of various functional cells in the future.

Probing the Size Effect of Graphene Oxide Nanosheets on Ice Crystal Regulation and Laser-Assisted Rapid Rewarming.

Two-dimensional (2D) nanomaterials have attracted many researchers to explore the effect of ice control and rapid deicing due to their functional groups, large specific surface area, and excellent photothermal properties. However, the impact of size effects on ice crystal formation, growth, and photothermal performance has been rarely explored. Here, graphene oxide nanosheets (GO NSs) with controllable sizes were used as a representative of 2D nanomaterials to probe the effect of size on ice crystal regulation and rapid rewarming in cell cryopreservation. All sizes of GO NSs exhibited notable inhibitory effects on ice crystal size during the recrystallization process. Significantly, when the size of GO NSs was smaller than a certain size (<150 nm), they showed a more significant ice recrystallization suppression effects, which could reduce the ice crystal size to about 17% of that of pure water. Meanwhile, the photothermal experiments also indicated that smaller-sized GO NSs exhibited better photothermal behavior, with 90 nm GO NSs (GO-90) heating to 70 °C in just 1 min induced by an 808 nm laser (2 W/cm2). Furthermore, applying GO-90 (200 μg/mL) to cell cryopreservation, cell viability could reach 95.2% and 93% with a low amount of traditional cryoprotectant (2% v/v DMSO) for A549 cells and HeLa cells after recovery, respectively. With the assistance of a 808 nm laser, the rewarming time was also shortened to 20 s, greatly improving the rewarming rate. Our work associated specific sizes of 2D nanomaterials with their ice growth inhibition behaviors during recrystallization and photothermal properties to synergistically improve cell cryopreservation efficiency, providing guidance for effectively designing novel 2D nanomaterials for collaborative control of ice crystals in cell cryopreservation.

Conditioned media and DMSO enhance the cryopreservation of bovine adipose tissue-derived mesenchymal stem cells

Mesenchymal stem cells derived from adipose tissue (AD-MSCs) show great potential for repro ductive biotechnology in the livestock sector. However, enzyme-based isolation of MSCs is expensive and time-consuming, so it is still rarely done, especially for applications in the livestock sector in de veloping countries. So, MSCs must be cryopreserved with an efficient cryoprotective agent to be stored and reproduced in various laboratories after isolation. This study was aimed to optimize the cryopreser vation media for adipose-derived MSCs in cattle. This study evaluated the viability, proliferation, and morphology of AD-MSCs. The results of this study indicate that a combination of 10% DMSO, 45% DMEM, and 45% conditioned media significantly improves post-thaw viability, proliferation, and sur vival as compared to other mediums. Furthermore, AD-MSCs cryopreserved in this medium exhibit similar morphology as fresh cells. These findings suggest that the optimized cryopreservation medium can enhance the quality and safety of AD-MSCs for clinical applications in the livestock industry.

Histological Identification of Germline Stem Cells’ Recipients for Conservation of Balkan Trout Fish Species by Transplantation Technology

Combining cryopreservation of germline stem cells (GSCs) with their subsequent transplantation into recipient fish is a powerful technique for long-term conservation of the genetic resources of threatened fish species. However, transplantation of GSCs has been limited by a failure to identify an appropriate recipient for surrogate production of donor-derived gametes. In the worst-case scenario, recipients may completely reject the transplanted GSCs due to an immunological reaction. This limitation can be overcome by specifying the gonadal status of both GSC donor and recipient species. This study used histological methods to identify possible GSC recipients for rescuing endangered trout fish species on the Balkan Peninsula. The study specified the gonadal status of brown trout, triploid rainbow trout, and tiger trout. The findings revealed that both triploid rainbow trout and tiger trout are sterile. The fish's testes contained only early-stage germ cells and did not develop past type-B spermatogonia, whereas the ovaries contained only oogonia. Both spermatogenesis and oogenesis were incomplete in these fish, and the gametes, i.e., functional spermatozoa and eggs, could not be formed. As a result, these fish make excellent recipients for GSC transplantation. Because most Balkan trout belong to the genus Salmo and closely related species, tiger trout would be a more feasible recipient of GSCs due to the small phylogenetic distance, as it is a hybrid of brown trout female and brook trout male.

Late Treatment With Autologous Expanded Regulatory T-cell Therapy After Alemtuzumab Induction Is Safe and Facilitates Immunosuppression Minimization in Living Donor Renal Transplantation.

The TWO Study (Transplantation Without Overimmunosuppression) aimed to investigate a novel approach to regulatory T-cell (Treg) therapy in renal transplant patients, using a delayed infusion protocol at 6 mo posttransplant to promote a Treg-skewed lymphocyte repopulation after alemtuzumab induction. We hypothesized that this would allow safe weaning of immunosuppression to tacrolimus alone. The COVID-19 pandemic led to the suspension of alemtuzumab use, and therefore, we report the unique cohort of 7 patients who underwent the original randomized controlled trial protocol. This study presents a unique insight into Treg therapy combined with alemtuzumab and is therefore an important proof of concept for studies in other diseases that are considering lymphodepletion. Living donor kidney transplant recipients were randomized to receive autologous polyclonal Treg at week 26 posttransplantation, coupled with weaning doses of tacrolimus, (Treg therapy arm) or standard immunosuppression alone (tacrolimus and mycophenolate mofetil). Primary outcomes were patient survival and rejection-free survival. Successful cell manufacturing and cryopreservation until the 6-mo infusion were achieved. Patient and transplant survival was 100%. Acute rejection-free survival was 100% in the Treg-treated group at 18 mo after transplantation. Although alemtuzumab caused a profound depletion of all lymphocytes, including Treg, after cell therapy infusion, there was a transient increase in peripheral Treg numbers. The study establishes that delayed autologous Treg therapy is both feasible and safe, even 12 mo after cell production. The findings present a new treatment protocol for Treg therapy, potentially expanding its applications to other indications.

Exploring the Cryopreservation Mechanism and Direct Removal Strategy of TAPS in Red Blood Cell Cryopreservation.

Cryopreservation of red blood cells (RBCs) plays an indispensable role in modern clinical transfusion therapy. Researchers are dedicated to finding cryoprotectants (CPAs) with high efficiency and low toxicity to prevent RBCs from cryopreservation injury. This study presents, for the first time, the feasibility and underlying mechanisms of a novel CPA called tris(hydroxymethyl)aminomethane-3-propanesulfonic acid (TAPS) in RBCs cryopreservation. The results demonstrated that the addition of TAPS achieved a post-thaw recovery of RBCs at 79.12 ± 0.67%, accompanied by excellent biocompatibility (above 97%). Subsequently, the mechanism for preventing RBCs from cryopreservation injury was elucidated. On one hand, TAPS exhibits a significant amount of bound water and effectively inhibits ice recrystallization, thereby reducing mechanical damage. On the other hand, TAPS demonstrates high capacity to scavenge reactive oxygen species and strong endogenous antioxidant enzyme activity, providing effective protection against oxidative damage. Above all, TAPS can be readily removed through direct washing, and the RBCs after washing showed no significant differences in various physiological parameters (SEM, RBC hemolysis, ESR, ATPase activity, and Hb content) compared to fresh RBCs. Finally, the presented mathematical modeling analysis indicates the good benefits of TAPS. In summary, TAPS holds potential for both research and practical in the field of cryobiology, offering innovative insights for the improvement of RBCs cryopreservation in transfusion medicine.

Successful transport across continents of GMP-manufactured and cryopreserved culture-expanded human fetal liver-derived mesenchymal stem cells for use in a clinical trial

IntroductionCell therapy has been increasingly considered to treat diseases, but it has been proven difficult to manufacture the same product at multiple manufacturing sites. Thus, for a wider implementation an alternative is to have one manufacturing site with a wide distribution to clinical sites. To ensure administration of a good quality cell therapy product with maintained functional characteristics, several obstacles must be overcome, which includes for example transfer of knowledge, protocols and procedures, site assessment, transportation and preparation of the product. MethodsAs the preparatory work for a clinical trial in India using fetal mesenchymal stem cells (fMSCs) developed and manufactured in Sweden, we performed a site assessment of the receiving clinical site, transferred methods, developed procedures and provided training of operators for handling of the cell therapy product. We further developed a Pharmacy Manual to cover the management of the product, from ordering it from the manufacturer, through transport, reconstitution, testing and administration at the clinical site. Lastly, the effect of long-distance transport on survival and function of, as well as the correct handling of the cell therapy product, was evaluated according to the pre-determined and approved Product Specification. ResultsFour batches of cryopreserved human fetal liver-derived fMSCs manufactured according to Good Manufacturing Practice and tested according to predetermined release criteria in Sweden, were certified and transported in a dry shipper at −150 °C to the clinical site in India. The transport was temperature monitored and took three–seven days to complete. The thawed and reconstituted cells showed more than 80% viability up to 3 h post-thawing, the cell recovery was more than 94%, the cells displayed the same surface protein expression pattern, differentiated into bone, had stable chromosomes and were sterile, which conformed with the data from the manufacturing site in Sweden. ConclusionsOur study shows the feasibility of transferring necessary knowledge and technology to be able to carry out a clinical trial with a cell therapy product in distant country. It also shows that it is possible to transport a cryopreserved cell therapy product over long distances and borders with retained quality. This extends the use of cryopreserved cell therapy products in the future.