Use Of Mesenchymal Stromal Cells Research Articles

Murine iPSC-Loaded Scaffold Grafts Improve Bone Regeneration in Critical-Size Bone Defects.

In certain situations, bones do not heal completely after fracturing. One of these situations is a critical-size bone defect where the bone cannot heal spontaneously. In such a case, complex fracture treatment over a long period of time is required, which carries a relevant risk of complications. The common methods used, such as autologous and allogeneic grafts, do not always lead to successful treatment results. Current approaches to increasing bone formation to bridge the gap include the application of stem cells on the fracture side. While most studies investigated the use of mesenchymal stromal cells, less evidence exists about induced pluripotent stem cells (iPSC). In this study, we investigated the potential of mouse iPSC-loaded scaffolds and decellularized scaffolds containing extracellular matrix from iPSCs for treating critical-size bone defects in a mouse model. In vitro differentiation followed by Alizarin Red staining and quantitative reverse transcription polymerase chain reaction confirmed the osteogenic differentiation potential of the iPSCs lines. Subsequently, an in vivo trial using a mouse model (n = 12) for critical-size bone defect was conducted, in which a PLGA/aCaP osteoconductive scaffold was transplanted into the bone defect for 9 weeks. Three groups (each n = 4) were defined as (1) osteoconductive scaffold only (control), (2) iPSC-derived extracellular matrix seeded on a scaffold and (3) iPSC seeded on a scaffold. Micro-CT and histological analysis show that iPSCs grafted onto an osteoconductive scaffold followed by induction of osteogenic differentiation resulted in significantly higher bone volume 9 weeks after implantation than an osteoconductive scaffold alone. Transplantation of iPSC-seeded PLGA/aCaP scaffolds may improve bone regeneration in critical-size bone defects in mice.

Application of mesenchymal stem cells in severe acute experimental pancreatitis

Background. The significance of the problem of acute pancreatitis is due to an increase in the incidence with an increase in the number of common forms of pancreatic necrosis, accompanied by a high incidence of severe complications.Aim. To determine the effect of regional application of mesenchymal stromal cells on the systemic manifestations of severe acute experimental pancreatitis.Material and methods. This experimental study was carried out on 42 adults Wistar rats. Acute pancreatitis was induced by administering 0.3 ml of 5% solution of non-ionic polyethylene glycol octylphenol ether detergent into the caudal part of the pancreas. The animals were randomly divided into 4 groups: Group I (n=6) consisting of intact animals, Group II (control group) (n=12) of rats with untreated pancreatitis, Group III (n=12) of rats with pancreatitis treated: anesthesia + infusions of 0.9% sodium chloride solution (saline), and Group IV (n=12) of rats with pancreatitis treated: anesthesia + infusions of saline + regional application of mesenchymal stromal cells. Animals were taken out of the experiment by euthanasia on the 3rd and 7th day. The hematological parameters, markers of systemic manifestation of the pathological process (pancreatic amylase, aspartate aminotransferase, alanine aminotransferase, urea, creatinine), markers of endogenous intoxication (lipid peroxidation activity, nitric oxide level), markers of systemic inflammatory response (C-reactive protein, tumour necrosis factor-alpha, interleukin-6) have been evaluated.Results. The application of mesenchymal stromal cells in the early stages of acute pancreatitis made a favourable effect on the platelet count, the level of glycemia, helped to reduce the content of endogenous intoxication elements (malonic dialdehyde, nitric oxide) and of those of the systemic inflammatory response (interleukin-6, tumor necrosis factor-α, C-reactive protein), which are key links in the pathogenesis of severe acute pancreatitis.Conclusion. Comparison of different treatment regimens for acute experimental pancreatitis has shown that the early use of mesenchymal stromal cells has a systemic positive effect and confirms the therapeutic efficacy of the method in the treatment of this disease.

Mesenchymal cells support the early retention of primary alveolar type 2 cells on acellular mouse lung scaffolds

ObjectivesTissue engineering approaches via repopulation of acellular biological grafts provide an exciting opportunity to generate lung grafts for transplantation. Alveolar type 2 (AT2) cells are a promising cell source for re-epithelialization. There are however inherent limitations with respect to their survival and growth, thus impeding their usability for tissue engineering applications. This study investigates the use of mesenchymal stromal cells to support primary AT2 cells for recellularization of mouse lung scaffolds. MethodsAT2 cells and bone marrow-derived mesenchymal cells (BMC) were co-delivered to decellularized mouse lung scaffolds. Recellularized lungs were evaluated for cell surface coverage, viability, and differentiation at 1 and 4 days after cell seeding. Recellularization was evaluated via histological analysis and immunofluorescence. ResultsSimultaneous delivery of AT2 and BMC into acellular lung scaffolds resulted in enhanced cell surface coverage and reduced AT2 cell apoptosis in the recellularized scaffolds at Day 1 but not Day 4. AT2 cell number decreased after 4 days in both of AT2 only and codelivery groups suggesting limited expansion potential in the scaffold. After retention in the scaffold, AT2 cells differentiated into Aqp5-expressing cells. ConclusionsOur results indicate that BMC support AT2 cell survival during the initial attachment and engraftment phase of recellularization. While our findings suggest only a short-term beneficial effect of BMC, our study demonstrates that AT2 cells can be delivered and retained in acellular lung scaffolds; thus with preconditioning and supporting cells, may be used for re-epithelialization. Selection and characterization of appropriate cell sources for use in recellularization, will be critical for ultimate clinical application.

THE EFFECT OF CHRONOLOGICAL AGE AND GENDER AND DIFFERENT SOURCE OF TISSUE ON THE IN VITRO PROPERTIES OF MESENCHYMAL STROMAL CELLS

AbstractObjectivesOsteoarthritis is a common articular cartilage disorder and causes a significant global disease burden. Articular cartilage has a limited capacity of repair and there is increasing interest in the use of cell-based therapies to facilitate repair including the use of Mesenchymal Stromal Cells (MSCs). There is some evidence in the literature that suggests that advancing age and gender is associated with declining MSC function, including reduced proliferation and differentiation potential, and greater cellular apoptosis. In our study, we first performed a systematic review of the literature to determine the effects of chronological age and gender on the in vitro properties of MSCs, and then performed a laboratory study to investigate these properties.Methods and ResultsWe initially conducted a PRISMA systematic review of the literature to review the evidence base for the effects of chronological age and gender on the in vitro properties of MSCs including cell numbers, expansion, cell surface characterization and differentiation potential. This was followed by laboratory-based experiments to assess these properties. Compare the extent of the effect of age on MSC cell marker expression, proliferation and pathways. Tissue from patients undergoing total knee replacement surgery was used to isolate MSCs from the synovium, fat pad and bone fragments using a method developed in our laboratory. The growth kinetics was determined by calculating the population doublings per day. Following expansion in culture, MSCs at P2 were characterised for a panel of cell surface markers using flow cytometry. The cells were positive for CD73, CD90 and CD105, and negative for antibody cocktail (eg included CD34, CD45). The differentiation potential of the MSCs was assessed through tri-lineage differentiation assays. At P2 after extracting RNA, we investigate the gene analysis using Bulk seq. Clear differences between the younger and older patients and gender were indicated.ConclusionsChronological age and gender-related changes in MSC function have important implications on the use of these cells in clinical applications for an ageing population. The results from this study will be used to plan further work looking at the effects of chronological age and gender on cellular senescence and identify pathways that could be targeted to potentially reverse any age and gender-related changes.Declaration of Interest(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Scale-Up of Academic Mesenchymal Stromal Cell Production

Background: Many clinical trials have reported the use of mesenchymal stromal cells (MSCs) following the indication of severe SARS-CoV-2 infection. However, in the COVID19 pandemic context, academic laboratories had to adapt a production process to obtain MSCs in a very short time. Production processes, especially freezing/thawing cycles, or culture medium have impacts on MSC properties. We evaluated the impact of an intermediate cryopreservation state during MSC culture to increase production yields. Methods: Seven Wharton’s jelly (WJ)-MSC batches generated from seven different umbilical cords with only one cryopreservation step and 13 WJ-MSC batches produced with intermediate freezing were formed according to good manufacturing practices. The identity (phenotype and clonogenic capacities), safety (karyotype, telomerase activity, sterility, and donor qualification), and functionality (viability, mixed lymphocyte reaction) were analyzed. Results: No significant differences between MSC production processes were observed, except for the clonogenic capacity, which was decreased, although it always remained above our specifications. Conclusions: Intermediate cryopreservation allows an increase in the production yield and has little impact on the basic characteristics of MSCs.

THE EFFECT OF CHRONOLOGICAL AGE ON THE IN VITRO PROPERTIES OF BONE FRAGMENT-DERIVED MESENCHYMAL STROMAL CELLS

Osteoarthritis is a common articular cartilage disorder and causes a significant global disease burden. Articular cartilage has a limited capacity of repair and there is increasing interest in the use of cell-based therapies to facilitate repair including the use of Mesenchymal Stromal Cells (MSCs). There is some evidence in the literature that suggests that advancing age is associated with declining MSC function, including reduced proliferation and differentiation potential, and greater cellular apoptosis. In our study, we first performed a systematic review of the literature to determine the effects of chronological age on the in vitro properties of MSCs, and then performed a laboratory study to investigate these properties.We initially conducted a PRISMA systematic review of the literature to review the evidence base for the effects of chronological age on the in vitro properties of MSCs including cell numbers, expansion, cell surface characterization and differentiation potential. This was followed by laboratory based experiments to assess these properties. Tissue from patients undergoing total knee replacement surgery was used to isolate MSCs from the bone fragments using a method developed in our laboratory. The growth kinetics was determined by calculating the population doublings per day. Following expansion in culture, MSCs at P2 were characterised for a panel of cell surface markers using flow cytometry. The cells were positive for CD73, CD90 and CD105, and negative for CD34 and CD45. The differentiation potential of the MSCs was assessed through tri-lineage differentiation assays. Clear differences between the younger and older patients were indicated.Chronological age-related changes in MSC function have important implications on the use of these cells in clinical applications for an ageing population. The results from this study will be used to plan further work looking at the effects of chronological age on cellular senescence and identify pathways that could be targeted to potentially reverse any age-related changes.

CHRONOLOGICAL AGE AFFECTS MSC SENESCENCE IN VITRO: A SYSTEMATIC REVIEW

The use of mesenchymal stromal cells (MSCs) in regenerative medicine and tissue engineering is well established, given their properties of self-renewal and differentiation. However, several studies have shown that these properties diminish with age, and understanding the pathways involved are important to provide regenerative therapies in an ageing population.In this PRISMA systematic review, we investigated the effects of chronological donor ageing on the senescence of MSCs. We identified 3023 studies after searching four databases including PubMed, Web of Science, Cochrane, and Medline. Nine studies met the inclusion and exclusion criteria and were included in the final analyses.These studies showed an increase in the expression of p21, p53, p16, ROS, and NF- B with chronological age. This implies an activated DNA damage response (DDR), as well as increased levels of stress and inflammation in the MSCs of older donors. Additionally, highlighting the effects of an activated DDR in cells from older donors, a decrease in the expression of proliferative markers including Ki67, MAPK pathway elements, and Wnt/ -catenin pathway elements was observed. Furthermore, we found an increase in the levels of SA- -galactosidase, a specific marker of cellular senescence.Together, these findings support an association between chronological age and MSC senescence. The precise threshold for chronological age where the reported changes become significant is yet to be defined and should form the basis for further scientific investigations. The outcomes of this review should direct further investigations into reversing the biological effects of chronological age on the MSC senescence phenotype.

Mesenchymal stromal cells modulate infection and inflammation in the uterus and mammary gland

The use of mesenchymal stromal cells (MSCs) is emerging as an efficacious and safe treatment for many infectious and non-infectious inflammatory diseases in human and veterinary medicine. Such use could be done to treat mastitis and metritis, which are the most common disease conditions affecting dairy cows leading to considerable economic losses and reduced animal welfare. Currently, both disease conditions are commonly treated using local and systemic administration of antibiotics. However, this strategy has many disadvantages including low cure rates and the public health hazards. Looking for alternative approaches, we investigated the properties of MSCs using in-vitro mammary and endometrial cell systems and in-vivo mastitis and metritis murine model systems. In-vitro, co-culture of mammary and uterus epithelial cells constructed with NF-kB reporter system, the master regulator of inflammation, demonstrated their anti-inflammatory effects in response to.LPS. In vivo, we challenge animals with field strains of mammary and utero pathogenic Escherichia coli and evaluated the effects of local and systemic application of MSC in the animal models. Disease outcome was evaluated using histological analysis, bacterial counts and gene expression of inflammatory markers. We show that MSC treatment reduced bacterial load in metritis and significantly modulated the inflammatory response of the uterus and mammary gland to bacterial infection. Most notably are the immune modulatory effects of remotely engrafted intravenous MSCs, which open new avenues to the development of MSC-based cell-free therapies.

Role of stem cells in arteriovenous access: perspective from Lower Middle Income Countries.

Adequately created well functional haemodialysis access is an important part for the physical and mental wellbeing of renal failure patients. Every effort should be made to enhance the patency of these accesses. Recently, stem cell treatment modalities have opened new avenues in the better patency of arteriovenous fistula. Use of mesenchymal stromal cells (MSC) to prevent venous neointimal hyperplasia have been studied with good success rates. Adopting such costly treatment modalities in low middle income class country like Pakistan is associated with significant challenges. This short report discusses the current role of stem cells in arteriovenous access and how this exciting modality can be utilized in our country.

Glucose Metabolism: Optimizing Regenerative Functionalities of Mesenchymal Stromal Cells Postimplantation.

Mesenchymal stromal cells (MSCs) are considered promising candidates for regenerative medicine applications. Their clinical performance postimplantation, however, has been disappointing. This lack of therapeutic efficacy is most likely due to suboptimal formulations of MSC-containing material constructs. Tissue engineers, therefore, have developed strategies addressing/incorporating optimized cell, microenvironmental, biochemical, and biophysical cues/stimuli to enhance MSC-containing construct performance. Such approaches have had limited success because they overlooked that maintenance of MSC viability after implantation for a sufficient time is necessary for MSCs to develop their regenerative functionalities fully. Following a brief overview of glucose metabolism and regulation in MSCs, the present literature review includes recent pertinent findings that challenge old paradigms and notions. We hereby report that glucose is the primary energy substrate for MSCs, provides precursors for biomass generation, and regulates MSC functions, including proliferation and immunosuppressive properties. More importantly, glucose metabolism is central in controlling in vitro MSC expansion, in vivo MSC viability, and MSC-mediated angiogenesis postimplantation when addressing MSC-based therapies. Meanwhile, in silico models are highlighted for predicting the glucose needs of MSCs in specific regenerative medicine settings, which will eventually enable tissue engineers to design viable and potent tissue constructs. This new knowledge should be incorporated into developing novel effective MSC-based therapies. Impact statement The clinical use of mesenchymal stromal cells (MSCs) has been unsatisfactory due to the inability of MSCs to survive and be functional after implantation for sufficient periods to mediate directly or indirectly a successful regenerative tissue response. The present review summarizes the endeavors in the past, but, most importantly, reports the latest findings that elucidate underlying mechanisms and identify glucose metabolism as the crucial parameter in MSC survival and the subsequent functions pertinent to new tissue formation of importance in tissue regeneration applications. These latest findings justify further basic research and the impetus for developing new strategies to improve the modalities and efficacy of MSC-based therapies.

The effectiveness of the use of mesenchymal stromal cells for the treatment of lacerated wounds under conditions of hypothermia and hypoxia

BACKGROUND: Patients Arctic conditions complicate the pathogenesis of various skin and soft tissue injuries. For the treatment of these diseases, the possibility of using multipotent mesenchymal stromal cells, which promote the proliferation of granular tissue cells, angiogenesis, and reduce the duration of the inflammatory phase during wound healing due to the secretion of cytokines and growth factors, is being considered.
 AIM: In order to evaluate the effectiveness of cell therapy, experimental studies were carried out on the model of a lacerated wound in rats under conditions of hypoxia and hypothermia.
 MATERIALS AND METHODS: The animals were kept in a climate chamber (15% oxygen, 4C) for 48 hours. Injury was applied 24 hours after placement in controlled conditions. The introduction of stem cells was carried out a day after the wound was applied. Mesenchymal stromal cells obtained from the red bone marrow of Wistar rats were used for injection. The cell culture used had an immunophenotype corresponding to stem cells and had the ability to differentiate in the osteogenic, chondrogenic and adipogenic directions. During the study, the degree of inflammatory reaction in injured tissues and the presence of possible pathological discharges from the wound canal were assessed in rats, and the thickness of the injured paw was measured.
 RESULTS: The stimulating effect of the suspension of mesenchymal stem cells on the dynamics of reducing the edema of the injured hip by 10% was established compared to the control group. To describe the process of inflammation, a histological analysis was performed on the 6th and 21st days after the wound was applied. On the 6th day of the study, a weak infiltration of lymphocytes in the muscle tissue was noted in rats that were injected with MMSC, which may indicate an earlier transition of the wound process to the proliferative phase.
 CONCLUSION: The stimulating effect of the suspension of mesenchymal stem cells on the dynamics of reducing the edema of the injured hip by 10% was established compared to the control group.

PRISMA-Compliant Meta-Analysis of Randomized Controlled Trials on Osteoarthritis of Knee Managed with Allogeneic vs Autologous MSCs: Efficacy and Safety Analysis.

Meta-analysis. Our objective is to review the randomized controlled trials (RCTs) that have been conducted previously on the topic of osteoarthritis of the knee to assess and compare the efficacy and safety of autologous and allogeneic sources of mesenchymal stromal cells (MSCs) in the treatment of osteoarthritis. We searched the electronic databases PubMed, Embase, Web of Science, and the Cochrane Library until August 2021 for randomised controlled trials (RCTs) analysing the efficacy and safety of autologous and allogeneic sources of MSCs in the management of knee osteoarthritis. These searches were conducted independently and in duplicate. The outcomes that were taken into consideration for analysis were the visual analogue score (VAS) for pain, the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), the Lysholm score, and adverse events. The OpenMeta [Analyst] software was utilised to carry out the analysis in the R platform. In total, 21 studies with a total of 936 patients were considered for this analysis. Because none of the studies made a direct comparison of the autologous and allogeneic sources of MSCs, we pooled the results of all of the included studies of both sources and made a comparative analysis of how the two types of MSCs fared in their respective applications. Although both allogeneic and autologous sources of MSCs demonstrated significantly better VAS improvement after 6 months (p = 0.006, p = 0.001), this trend was not maintained after 1 year for the allogeneic source (p = 0.171, p = 0.027). When compared to their respective controls based on WOMAC scores after 1 year, autologous sources (p = 0.016) of MSCs performed better than allogeneic sources (p = 0.186).A similar response was noted between the sources at 2years in their Lysholm scores (p = 0.682, p = 0.017), respectively. Moreover, allogeneic sources (p = 0.039) of MSCs produced significant adverse events than autologous sources (p = 0.556) compared to their controls. Our analysis of literature showed that autologous sources of MSCs stand superior to allogeneic sources of MSC with regard to their consistent efficacy for pain, functional outcomes, and safety. However, we strongly recommend that further studies be conducted that are of a high enough quality to validate our findings and reach a consensus on the best source of MSCs for use in cellular therapy treatments for knee osteoarthritis. The online version contains supplementary material available at 10.1007/s43465-022-00751-z.

Abstract 12 Phase I Study of Cord Tissue Derived Mesenchymal Stromal Cells in COVID-19–Related Acute Respiratory Distress Syndrome

IntroductionSARS-CoV-2 infection results in the COVID-19 disease that caused a global pandemic. In severe cases, COVID-19 leads to acute respiratory distress syndrome (ARDS), due to direct lung injury and hyperinflammatory response. COVID-related ARDS treatment now includes remdesivir, dexamethasone, and anti-inflammatory monoclonal antibodies, which have decreased the mortality rate, yet patients continue to die from sepsis or multiorgan failure and new treatments are needed. The use of mesenchymal stromal cells (MSC) offers a unique therapeutic option that may shorten time to lung injury resolution through anti-inflammatory, immune-modulatory, and regenerative mechanisms.ObjectiveThe aim of this study was to test the safety of human cord tissue-derived MSCs (hCT-MSC) in patients with COVID-related ARDS. This study was funded by The Marcus Foundation.MethodsIn this phase I multisite study, 10 adults with COVID- related ARDS were treated with 3 daily intravenous infusions of hCT-MSCs (1 million cells/kg/dose, maximum dose 100 million cells with a post thaw viability ≥70%). Patients were excluded if they had evidence of multiorgan failure, immunodeficiency, or were receiving extracorporeal membrane oxygenation or not expected to survive more than 24 hours. The primary endpoint was short-term safety of hCT-MSC infusions. The secondary endpoints included 28-day survival and changes in the Murray Lung Injury Score.ResultsFrom August to November 2020, 10 patients (7 females, 3 males; 2 Black, 6 White, 2 other; 3 Hispanic or Latino), with a median age of 61.5 years (range 39-97), were enrolled at 2 sites. There were no infusion-related or study-related adverse events. The average cell dose administered was 0.94 ± 0.29 cells/kg, and average cell viability was 85% ± 11%; 5 of 30 (17%) doses were less than the study dose, and 29 of 30 (97%) met the ≥70% viability criteria. There were 28 non-serious adverse events in 3 unique patients and 2 serious adverse events in 2 unique patients, which were expected and deemed unrelated to the study product. Five patients died: 3 by day 28 and 2 by day 90. All deaths were determined to be unrelated to the hCT-MSCs. The Murray Lung Injury Score did not appear to change over the 28-day study period.DiscussionhCT-MSCs infusions are safe in patients with COVID-related ARDS. Future studies determining their efficacy are warranted.

Hyperthermia-stimulated tonsil-mesenchymal stromal cells suppress hematological cancer cells through downregulation of IL-6.

There are contradictory reports on the use of mesenchymal stromal cells (MSCs) in cancer therapy. Variable outcomes have been associated with several factors including cancer pathology, experimental procedure, MSC source tissue, and individual genetic differences. It is also known that MSCs exert their therapeutic effects with various paracrine factors released from these cells. The profiles of the factors released from MSCs are altered by heat shock, hypoxia, oxidative stress, starvation or various agents such as inflammatory cytokines, and their therapeutic potential is affected. In this study, the antitumor potential of conditioned media (CM), which contains paracrine factors, of mild hyperthermia-stimulated mesenchymal stromal cells derived from lymphoid organ tonsil tissue (T-MSC) was investigated in comparison with CM obtained from T-MSCs grew under normal culture conditions. CM was obtained from T-MSCs that were successfully isolated from palatine tonsil tissue and characterized. The cytotoxic effect of CM on the growth of hematological cancer cell lines at different concentrations (1:1 and 1:2) was demonstrated by methylthiazoldiphenyl-tetrazolium bromide analysis. In addition, the apoptotic effect of T-MSC-CM treatment was evaluated on the cancer cells using Annexin-V/PI detection method by flow cytometry. The pro/anti-apoptotic and cytokine-related gene expressions were also analyzed by real-time polymerase chain reactionpost T-MSC-CM treatment. In conclusion, we demonstrated that the factors released from hyperthermia-stimulated T-MSCs induced apoptosis in hematological cancer cell lines in a dose-dependent manner. Importantly, our results at the transcriptional level support that the factors and cytokines released from hyperthermia-stimulated T-MSC may exert antitumoral effects in cancer cells by downregulation of IL-6 that promotestumorigenesis. These findings reveal that T-MSC-CM can be a powerful cell-free therapeutical strategy for cancer therapy.

Preclinical Development of a Therapy for Chronic Traumatic Spinal Cord Injury in Rats Using Human Wharton's Jelly Mesenchymal Stromal Cells: Proof of Concept and Regulatory Compliance.

(1) Background: the use of Mesenchymal Stromal Cells (MSC) in emerging therapies for spinal cord injury (SCI) hold the potential to improve functional recovery. However, the development of cell-based medicines is challenging and preclinical studies addressing quality, safety and efficacy must be conducted prior to clinical testing; (2) Methods: herein we present (i) the characterization of the quality attributes of MSC from the Wharton’s jelly (WJ) of the umbilical cord, (ii) safety of intrathecal infusion in a 3-month subchronic toxicity assessment study, and (iii) efficacy in a rat SCI model by controlled impaction (100 kdynes) after single (day 7 post-injury) and repeated dose of 1 × 106 MSC,WJ (days 7 and 14 post-injury) with 70-day monitoring by electrophysiological testing, motor function assessment and histology evaluation; (3) Results: no toxicity associated to MSC,WJ infusion was observed. Regarding efficacy, recovery of locomotion was promoted at early time points. Persistence of MSC,WJ was detected early after administration (day 2 post-injection) but not at days 14 and 63 post-injection. (4) Conclusions: the safety profile and signs of efficacy substantiate the suitability of the presented data for inclusion in the Investigational Medicinal Product Dossier for further consideration by the competent Regulatory Authority to proceed with clinical trials.

Possible Effect of the use of Mesenchymal Stromal Cells in the Treatment of Autism Spectrum Disorders: A Review.

Autism spectrum disorder (ASD) represents a set of heterogeneous neurodevelopmental conditions defined by impaired social interactions and repetitive behaviors. The number of reported cases has increased over the past decades, and ASD is now a major public health burden. So far, only treatments to alleviate symptoms are available, with still unmet need for an effective disease treatment to reduce ASD core symptoms. Genetic predisposition alone can only explain a small fraction of the ASD cases. It has been reported that environmental factors interacting with specific inter-individual genetic background may induce immune dysfunctions and contribute to the incidence of ASD. Such dysfunctions can be observed at the central level, with increased microglial cells and activation in ASD brains or in the peripheral blood, as reflected by high circulating levels of pro-inflammatory cytokines, abnormal activation of T-cell subsets, presence of auto-antibodies and of dysregulated microbiota profiles. Altogether, the dysfunction of immune processes may result from immunogenetically-determined inefficient immune responses against a given challenge followed by chronic inflammation and autoimmunity. In this context, immunomodulatory therapies might offer a valid therapeutic option. Mesenchymal stromal cells (MSC) immunoregulatory and immunosuppressive properties constitute a strong rationale for their use to improve ASD clinical symptoms. In vitro studies and pre-clinical models have shown that MSC can induce synapse formation and enhance synaptic function with consequent improvement of ASD-like symptoms in mice. In addition, two preliminary human trials based on the infusion of cord blood-derived MSC showed the safety and tolerability of the procedure in children with ASD and reported promising clinical improvement of core symptoms. We review herein the immune dysfunctions associated with ASD provided, the rationale for using MSC to treat patients with ASD and summarize the current available studies addressing this subject.

Manufacturing Mesenchymal Stromal Cells for the Treatment of Osteoarthritis in Canine Patients: Challenges and Recommendations

The recent interest in advanced biologic therapies in veterinary medicine has opened up opportunities for new treatment modalities with considerable clinical potential. Studies with mesenchymal stromal cells (MSCs) from animal species have focused on in vitro characterization (mostly following protocols developed for human application), experimental testing in controlled studies and clinical use in veterinary patients. The ability of MSCs to interact with the inflammatory environment through immunomodulatory and paracrine mechanisms makes them a good candidate for treatment of inflammatory musculoskeletal conditions in canine species. Analysis of existing data shows promising results in the treatment of canine hip dysplasia, osteoarthritis and rupture of the cranial cruciate ligament in both sport and companion animals. Despite the absence of clear regulatory frameworks for veterinary advanced therapy medicinal products, there has been an increase in the number of commercial cell-based products that are available for clinical applications, and currently the commercial use of veterinary MSC products has outpaced basic research on characterization of the cell product. In the absence of quality standards for MSCs for use in canine patients, their safety, clinical efficacy and production standards are uncertain, leading to a risk of poor product consistency. To deliver high-quality MSC products for veterinary use in the future, there are critical issues that need to be addressed. By translating standards and strategies applied in human MSC manufacturing to products for veterinary use, in a collaborative effort between stem cell scientists and veterinary researchers and surgeons, we hope to facilitate the development of quality standards. We point out critical issues that need to be addressed, including a much higher level of attention to cell characterization, manufacturing standards and release criteria. We provide a set of recommendations that will contribute to the standardization of cell manufacturing methods and better quality assurance.

Successful Treatment of COVID-19 Patient on ECMO Using Mesenchymal Stromal Cells (MSC)-Derived Exosomes: A Case Report

IntroductionThe use of mesenchymal stromal cells (MSC) was recently proposed as a promising intervention for COVID-19 related respiratory failure (RF). Prior studies have suggested that its larger size might lead to entrapment in extracorporeal membrane oxygenation (ECMO), affect circuit function, and attenuate its efficacy. We present a successful case of a severe COVID-19 patient treated with MSC-derived exosomes while receiving veno-venous (VV) ECMO support.Case Report41-year-old unvaccinated obese White male with no past medical history presenting with shortness of breath and a +COVID-19 nasopharyngeal test was admitted receiving high-flow nasal cannula (HFNC), remdesivir, and dexamethasone (Day 1), followed by intubation (day 5), and a peripheral VV ECMO insertion (day 10) due to worsening RF. We used bivalirudin for post-ECMO anticoagulation. Subsequently, he received the first cycle of MSC-derived exosomes on alternative days (day 1, 3, & 5) between days 13-17, followed by the second cycle between days 34-38. After administration of exosomes, the plasma concentration of inflammatory markers reduced, including a decrease of 77% for ferritin, 74% for CRP, and 62% for procalcitonin in approximately one week, along with consistent improvement of PaO2/FiO2 ratio. ECMO membrane oxygenator was exchanged on day 23 at the time of tracheostomy. After successful weaning, ECMO decannulation was performed on day 47, and the patient was discharged home on day 61.SummaryECMO has emerged as a supportive strategy for patients with severe COVID-19 related RF. The patient's inflammatory response has been implicated in the pathophysiology of lung failure. Multiple pharmacological methods are employed to control the severity of this inflammatory response, thus preventing progression to the fibrotic stage of the disease. In our experience, MSC-derived exosomes neither resulted in any side effects nor impaired the function of ECMO and might have enhanced the recovery of the patient.

Mesenchymal Stromal Cells for Treating Steroid-Resistant Acute and Chronic Graft Versus Host Disease: A Multicenter Compassionate Use Experience.

Graft versus host disease (GVHD) is a severe complication after allogenic hematopoietic cell transplantation (HSCT). Several clinical trials have reported the use of mesenchymal stromal cells (MSCs) for the treatment of GVHD. In March 2008, the Andalusian Health Care System launched a compassionate use program to treat steroid-resistant GVHD with MSC. Clinical-grade MSC were obtained under GMP conditions. MSC therapy was administered intravenously in four separate doses of 1 × 106 cells/kg. Sixty-two patients, 45 males (7 children) and 17 females (2 children), received the treatment. Patients had a median age of 39 years (range: 7–66) at the time of the allogenic HSCT. The overall response was achieved in 58.7% of patients with acute (a)GVHD. Two years’ survival for aGVHD responders was 51.85%. The overall response for patients with chronic (c)GVHD was 65.50% and the 2-year survival rate for responders was 70%. Age at the time of HSCT was the only predictor found to be inversely correlated with survival in aGVHD. Regarding safety, four adverse events were reported, all recovered without sequelae. Thus, analysis of this compassionate use experience shows MSC to be an effective and safe therapeutic option for treating refractory GVHD, resulting in a significant proportion of patients responding to the therapy.

Humoral Immunity to Allogeneic Immunoproteasome-Expressing Mesenchymal Stromal Cells Requires Efferocytosis by Endogenous Phagocytes.

The extensive use of mesenchymal stromal cells (MSCs) over the last decade has revolutionized modern medicine. From the delivery of pharmacological proteins to regenerative medicine and immune modulation, these cells have proven to be highly pleiotropic and responsive to their surrounding environment. Nevertheless, their role in promoting inflammation has been fairly limited by the questionable use of interferon-gamma, as this approach has also been proven to enhance the cells’ immune-suppressive abilities. Alternatively, we have previously shown that de novo expression of the immunoproteasome (IPr) complex instills potent antigen cross-presentation capabilities in MSCs. Interestingly, these cells were found to express the major histocompatibility class (MHC) II protein, which prompted us to investigate their ability to stimulate humoral immunity. Using a series of in vivo studies, we found that administration of allogeneic ovalbumin (OVA)-pulsed MSC-IPr cells elicits a moderate antibody titer, which was further enhanced by the combined use of pro-inflammatory cytokines. The generated antibodies were functional as they blocked CD4 T-cell activation following their co-culture with OVA-pulsed MSC-IPr and mitigated E.G7 tumor growth in vivo. The therapeutic potency of MSC-IPr was, however, dependent on efferocytosis, as phagocyte depletion prior to vaccination abrogated MSC-IPr-induced humoral responses while promoting their survival in the host. In contrast, antibody-mediated neutralization of CD47, a potent “do not eat me signal”, enhanced antibody titer levels. These observations highlight the major role played by myeloid cells in supporting antibody production by MSC-IPr and suggest that the immune outcome is dictated by a net balance between efferocytosis-stimulating and -inhibiting signals.