Immunomodulatory characteristics of mesenchymal stem cells and their role in the treatment of multiple sclerosis

The Role of Mesenchymal Stem Cells in Modulating Adaptive Immune Responses in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system, leading to significant disability through neurodegeneration. Despite advances in the understanding of MS pathophysiology, effective treatments remain limited. Mesenchymal stem cells (MSCs) have gained attention as a potential therapeutic option due to their immunomodulatory and regenerative properties. This review examines MS pathogenesis, emphasizing the role of immune cells, particularly T cells, in disease progression, and explores MSCs' therapeutic potential. Although preclinical studies in animal models show MSC efficacy, challenges such as donor variability, culture conditions, migratory capacity, and immunological compatibility hinder widespread clinical adoption. Strategies like genetic modification, optimized delivery methods, and advanced manufacturing are critical to overcoming these obstacles. Further research is needed to validate MSCs' clinical application in MS therapy.

Stem Cells and Stem Cell-Derived Factors for the Treatment of Inflammatory Bowel Disease with a Particular Focus on Perianal Fistulizing Disease: A Minireview on Future Perspectives

Inflammatory bowel disease remains a difficult disease to effectively treat, especially fistulizing Crohn's disease. Perianal fistulas in the setting of Crohn's disease remain an area of unmet need with significant morbidity in this patient population. Up to one third of Crohn's patients will have perianal fistulizing disease and current medical and surgical interventions are of limited efficacy. Thus, most patients experience significant morbidity, narcotic use, and loss of employment and end up with multiple surgical interventions. Mesenchymal stem cells (MSCs) have shown efficacy in phase 3 clinical trials, but considerable infrastructure challenges make MSCs limited with regard to scalability in clinical practice. Extracellular vesicles, being derived from MSCs and capturing the secretome functionality of MSCs, offer similar physiological utility regarding mechanism, while also providing an off the shelf regenerative medicine product that could be widely used in daily clinical practice.

Meta-analysis shows that mesenchymal stem cell therapy can be a possible treatment for diabetes

Objective

This meta-analysis includes the systematic literature review and meta-analysis involving clinical trials to assess the efficacy and safety of mesenchymal stem cell (MSC) transplantation for treating T1DM and T2DM.

Methods

We searched PubMed, ScienceDirect, Web of Science, clinicaltrials.gov, and Cochrane Library for "published" research from their inception until November 2023. Two researchers independently reviewed the studies' inclusion and exclusion criteria. Our meta-analysis included 13 studies on MSC treatment for diabetes.

Results

The MSC-treated group had a significantly lower HbA1c at the last follow-up compared to the baseline (MD: 0.95, 95% CI: 0.33 to 1.57, P-value: 0.003< 0.05), their insulin requirement was significantly lower (MD: 0.19, 95% CI: 0.07 to 0.31, P-value: 0.002< 0.05), the level of FBG with MSC transplantation significantly dropped compared to baseline (MD: 1.78, 95% CI: -1.02 to 4.58, P-value: 0.212), the FPG level of the MSC-treated group was significantly lower (MD: -0.77, 95% CI: -2.36 to 0.81, P-value: 0.339 > 0.05), and the fasting C-peptide level of the MSC-treated group was slightly high (MD: -0.02, 95% CI: -0.07 to 0.02, P-value: 0.231 > 0.05).

Conclusion

The transplantation of MSCs has been found to positively impact both types of diabetes mellitus without signs of apparent adverse effects.

Development of an injectable chitosan-based hydrogel containing nano-hydroxy-apatite and alendronate for MSC-based therapy

BACKGROUND

The combination of cells and biomaterials has become a powerful approach to regenerative medicine in recent years. Understanding the in-vitro interactions between cells and biomaterials is crucial for the success of regenerative medicine.

AIM

In this study, we developed an AD-pectin/chitosan/nano-crystalline cellulose scaffold with nano-hydroxy-apatite (n-HAP) and alendronate (ALN). The second step was to evaluate its effect on the immunomodulatory properties and biological behaviors of seeded adipose-derived mesenchymal stem cells (ADSCs) for bone tissue repair.

MATERIAL AND METHOD

After preparing and evaluating the characterization tests of the new combined n-HAP scaffold, we established different culture conditions to evaluate ADSC growth on this scaffold with or without ALN. The main assays were MTT assay, RT-PCR, and ELISA.

RESULTS

Our data regarding characterization tests (including SEM, TGA, FTIR, gelation time, swelling ratio, rheology and degradation tests) of ALN-loaded n-HAP scaffold showed the proper stability and good mechanical status of the scaffold. ADSC proliferation and viability increased in the presence of the scaffold compared with other conditions. Moreover, our data demonstrated increased gene expression and protein levels of anti-inflammatory TGF-β, HGF, and IDO cytokines in the presence of the ALN-loaded n-HAP scaffold, indicating the increased immunosuppressive activity of ADSCs in vitro.

CONCLUSION

This study demonstrates the promising abilities of the ALN-loaded n-HAP scaffold to increase the proliferation, viability, and immunomodulatory capacity of ADSCs, elucidating new aspects of cell-material interactions that can be used for bone tissue regeneration/repair, and paving the path of future research in developing new approaches for MSC- based therapy.

Estriol and commensal microflora strains regulate innate lymphoid cells functional activity in multiple sclerosis

Multiple sclerosis (MS) is an autoimmune neurodegenerative disease in which the immune system attacks myelin basic protein of nerve axons. Recently, there has been growing interest in studying the role of a newly described population of immunity cells - innate lymphoid cells (ILCs) in the pathogenesis of the disease. At the same time, it was found that during pregnancy there is a weakening of Th1-mediated autoimmune pathologies manifestations, including MS. In this work, we studied phenotypic characteristics of ILC in MS patients in comparison with healthy donors after 48 h incubation with pregnancy hormone estriol (E3) and commensal microflora cells. To activate ILC, strains of Ecsherichia coli K12 and Lactobacillus plantarum 8R-A3 were used. ILC phenotype was assessed by flow cytometry using monoclonal antibody staining. It has been established that E3 and bacterial factors are able to regulate the maturation of ILC subtypes and their cytokines in different ways. In general, the studied factors influence the phenotypic changes in ILC cells, leading to the transition from one type to another, both in healthy donors and in MS patients.

STA-21, a small molecule STAT3 inhibitor, ameliorates experimental autoimmune encephalomyelitis by altering Th-17/Treg balance

BACKGROUND

Numerous studies have demonstrated the role of T helper (Th) 17 and T regulatory (reg) cells and pro-inflammatory and anti-inflammatory cytokines related to these cells in the pathogenesis of MS and its animal model, experimental autoimmune encephalomyelitis (EAE). STAT3 is one of the downstream signaling proteins of IL-23, IL-6, and IL-21 that are required for Th17 cells differentiation. STA-21 is a STAT3 inhibitor that functions by inhibiting STAT3 dimerization and binding to DNA impairing the expression of STAT3 target genes including, RORγt, IL-21 and IL-23R that are also required for Th17 cell differentiation.

AIM

In this study, we evaluated the effect of STA-21 on EAE Model and investigated how this small molecule can change Th17/Treg balance leading to amelioration of disease.

METHODS

After EAE induction and treatment with STA-21, its effects were assessed. Major assays were H&E and LFB staining, Flow cytometric analysis, Reverse transcription-PCR (RT-PCR), and ELISA.

RESULTS

STA-21 ameliorated the EAE severity and decreased the EAE inflammation and demyelination. It also decreased STAT3 phosphorylation, the proportion of Th17 cells and the protein level of IL-17. In contrast, the balance of Tregs and the level of anti-inflammatory cytokine, IL-10 increased in STA-21-treated mice. Moreover, STA-21 significantly decreased the expression of Th17 related transcription factors, RORɣt and IL-23R while FOXP3 expression associated with Treg differentiation was increased.

CONCLUSION

This study showed that STA-21 has therapeutic effects in EAE by reducing inflammation and shifting inflammatory immune responses to anti-inflammatory and can be used as a suitable treatment strategy for the treatment of EAE. The effectiveness of inhibiting or strengthening the functional cells of the immune system by these small molecules in terms of easy to access, simple construction and inexpensive expansion make them as a suitable tool for the treatment of inflammatory and autoimmune diseases.

Mesenchymal stem cells: A novel treatment option for primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a progressive liver disease for which there is no effective therapy. Hepatocytes and cholangiocytes from a PSC patient were cocultured with mesenchymal stem cells (MSCs) to assess in vitro change. A single patient with progressive PSC was treated with 150 million MSCs via direct injection into the common bile duct. Coculture of MSCs with cholangiocytes and hepatocytes showed in vitro improvement. Local delivery of MSCs into a single patient with progressive PSC was safe. Radiographic and endoscopic evaluation showed stable distribution of multifocal structuring in the early postoperative period. MSCs may be effective for the treatment of PSC.

Durable Response in Patients With Refractory Fistulizing Perianal Crohn's Disease Using Autologous Mesenchymal Stem Cells on a Dissolvable Matrix: Results from the Phase I Stem Cell on Matrix Plug Trial

BACKGROUND

Refractory perianal Crohn's disease remains notoriously difficult to treat. We developed a novel technology using a commercially available bioabsorbable fistula plug to deliver autologous adipose-derived mesenchymal stem cells.

OBJECTIVE

This study aimed to assess therapeutic safety and feasibility in the completed STOMP (stem cells on matrix plugs) phase 1 clinical trial.

DESIGN

Prospective single-arm phase I clinical trial.

SETTING

Tertiary academic medical center.

PATIENTS

Adults (aged 18-65 y) with complex single-tract Crohn's disease perianal fistula who have failed conventional therapy were included in this study.

INTERVENTION

Autologous adipose-derived mesenchymal stem cells were isolated, ex vivo culture expanded, and seeded onto a commercially available bioabsorbable fistula plug. Six weeks later, patients returned to the operating room for removal of the seton and placement of the stem cell-loaded plug.

MAIN OUTCOME MEASURES

Patients were followed up for a total of 8 visits through 12 months. Safety was the primary end point; clinical healing and MRI response were secondary end points.

RESULTS

Twenty patients (12 females; mean age 36 y) were treated with the stem cell-loaded plug. Of the 20 patients enrolled, 3 were not included in the 12-month analysis because of study withdrawal. Through 12 months, no patient experienced a serious adverse event related to the stem cell-loaded plug. Four patients experienced 7 serious adverse events and 12 patients experienced 22 adverse events. Complete clinical healing occurred in 14 of 18 patients at 6 months and 13 of 17 patients at 12 months. MRI response was observed in 12 of 18 patients at 6 months.

LIMITATIONS

The main limitations were the small sample size and restrictive inclusion criteria.

CONCLUSIONS

A stem cell-loaded plug can safely and effectively deliver cell-based therapy for patients with single-tract fistulizing perianal Crohn's disease. See Video Abstract at http://links.lww.com/DCR/C70 .

RESPUESTA DURADERA OBSERVADA EN PACIENTES CON ENFERMEDAD DE CROHN PERIANAL FISTULIZANTE REFRACTARIA MEDIANTE EL USO DE CLULAS MADRE MESENQUIMALES AUTLOGAS EN UNA MATRIZ DISOLUBLE RESULTADOS DEL ENSAYO DE FASE I STEM CELL ON MATRIX PLUG

ANTECEDENTES:La enfermedad de Crohn perianal refractaria sigue siendo notoriamente difícil de tratar. Desarrollamos una tecnología novedosa utilizando un tapón de fístula bioabsorbible disponible comercialmente para administrar células madre mesenquimales derivadas de tejido adiposo autólogo.OBJETIVO:Evaluar la seguridad y viabilidad terapéutica en el ensayo finalizado STOMP.DISEÑO:Ensayo clínico prospectivo de fase I de un solo brazo.AJUSTE:Centro médico académico terciario.PACIENTES:Adultos (18-65) con fístula perianal compleja de la enfermedad de Crohn de un solo tracto que han fracasado con la terapia convencional.INTERVENCIÓN:Se aislaron células madre mesenquimales derivadas de tejido adiposo autólogo, se expandieron en cultivo ex vivo y se sembraron en un tapón de fístula bioabsorbible disponible comercialmente. Seis semanas después, los pacientes regresaron al quirófano para retirar el setón y colocar el tapón cargado de células madre.PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes fueron seguidos durante un total de 8 visitas durante 12 meses. La seguridad fue el criterio principal de valoración; la curación clínica y la respuesta a la resonancia magnética fueron criterios de valoración secundarios.RESULTADOS:Veinte pacientes (12 mujeres, edad media 36 años) fueron tratados con el tapón cargado de células madre. De los 20 pacientes inscritos, tres no se incluyeron en el análisis de 12 meses porque se retiraron del estudio. A lo largo de 12 meses, ningún paciente experimentó un evento adverso grave relacionado con el tapón cargado de células madre. Cuatro pacientes experimentaron 7 eventos adversos graves y 12 pacientes experimentaron 22 eventos adversos. La curación clínica completa ocurrió en 14 de 18 pacientes a los 6 meses y en 13 de 17 pacientes a los 12 meses. La respuesta a la resonancia magnética se observó en 12 de 18 pacientes a los 6 meses.LIMITACIONES:Las principales limitaciones son el tamaño pequeño de la muestra y los criterios de inclusión restrictivos.CONCLUSIONES:Un tapón cargado de células madre se puede administrar de manera segura y efectiva, una terapia basada en células para pacientes con enfermedad de Crohn perianal fistulizante de un solo tracto. Consule Video Resumen en http://links.lww.com/DCR/C70 . (Traducción- Dr. Yesenia Rojas-Khalil ).

Use of Mesenchymal Stem Cells in Crohn's Disease and Perianal Fistulas: A Narrative Review

Crohn's Disease (CD), which usually leads to anal fistulas among patients, is the most important inflammatory bowel disease that causes morbidity in many people around the world. This review article proposes using MSCs as a hopeful therapeutic strategy for CD and anal fistula treatment in both preclinical and clinical conditions. Finally, darvadstrocel, a cell-based medication to treat complex anal fistulas in adults, as the only European Medicines Agency (EMA)-approved product for the treatment of anal fistulas in CD is addressed. Although several common therapies, such as surgery and anti-tumor necrosis factor-alpha (TNF-α) drugs as well as a combination of these methods is used to improve this disease, however, due to the low effectiveness of these treatments, the use of new strategies with higher efficiency is still recommended. Cell therapy is among the new emerging therapeutic strategies that have attracted great attention from clinicians due to its unique capabilities. One of the most widely used cell sources administrated in cell therapy is mesenchymal stem cell (MSC). This review article will discuss preclinical and clinical studies about MSCs as a potent and promising therapeutic option in the treatment of CD and anal fistula.

A phase IB/IIA study of remestemcel-L, an allogeneic bone marrow-derived mesenchymal stem cell product, for the treatment of medically refractory ulcerative colitis: an interim analysis

AIM

There have been no studies into the direct injection of mesenchymal stem cells (MSCs) for luminal ulcerative colitis (UC). Our aim was to investigate the efficacy of MSCs delivered locally via endoscopic delivery, as is done in the setting of perianal disease, to treat the local site of inflammation directly.

METHOD

A phase IB/IIA randomized control clinical trial of remestemcel-L, an ex vivo expanded allogeneic bone marrow-derived MSC product, at a dose of 150 million MSCs versus placebo (2:1 fashion) delivered via direct injection using a 23-gauge sclerotherapy needle at the time of colonoscopy was designed to assess the safety and efficacy of endoscopic delivery of MSCs for UC. The main outcome measures were adverse events, Mayo score and Mayo endoscopic severity score at 2 weeks, 6 weeks and 3 months post-MSC delivery.

RESULTS

Six patients were enrolled and treated; four received MSCs and two placebo. All had been on prior anti-tumour necrosis factor or anti-integrin therapy. There were no adverse events related to MSCs. In the treatment group (n = 4), the Mayo endoscopic severity score decreased in all patients by 2 weeks after MSC delivery. At 3 months, all patients were extremely satisfied or satisfied with their MSC treatment based on the inflammatory bowel disease patient-reported treatment impact (IBD-PRTI), and treatment response was described as excellent or good in all patients. In the control group (n = 2), the Mayo endoscopic severity score did not increase as a result of being off alternative therapy. At 3 months, patients were dissatisfied according to the IBD-PRTI, and treatment response was poor or unchanged.

CONCLUSION

MSCs may offer a safe therapeutic option for the treatment of medically refractory UC. Early data suggest improved clinical and endoscopic scores by 2 weeks after MSC delivery.

The microenvironment of silk/gelatin nanofibrous scaffold improves proliferation and differentiation of Wharton's jelly-derived mesenchymal cells into islet-like cells

The use of umbilical cord-derived mesenchymal stem cells along with three-dimensional (3D) scaffolds in pancreatic tissue engineering can be considered as a treatment for diabetes. This study aimed to investigate the differentiation of Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) into pancreatic islet-insulin producing cells (IPCs) on silk/gelatin nanofibers as a 3D scaffold. Mesenchymal markers were evaluated at the mesenchymal stem cells (MSCs) level by flow cytometry. WJ-MSCs were then cultured on 3D scaffolds and treated with a differential medium. Immunocytochemical assays showed efficient differentiation of WJ-MSCs into IPCs. Also, Real-time PCR results showed a significant increase in the expression of pancreatic genes in the 3D culture group compared to the two-dimensional (2D) culture group. Despite these cases, the secretion of insulin and C-peptide in response to different concentrations of glucose in the 3D group was significantly higher than in the 2D culture. The results of our study showed that silk/gelatin scaffold with WJ-MSCs could be a good option in the production of IPCs in regenerative medicine and pancreatic tissue engineering.

Efficacy and Safety of Mesenchymal Stem Cell Transplantation in the Treatment of Autoimmune Diseases (Rheumatoid Arthritis, Systemic Lupus Erythematosus, Inflammatory Bowel Disease, Multiple Sclerosis, and Ankylosing Spondylitis): A Systematic Review and Meta-Analysis of Randomized Controlled Trial

Objective

To evaluate the efficacy and safety of mesenchymal stem cell (MSC) transplantation in the treatment of autoimmune diseases.

Methods

The Chinese and English databases were searched for clinical research on the treatment of autoimmune diseases with mesenchymal stem cells. The search time range is from a self-built database to October 1, 2021. Two reviewers independently screened the literature according to the inclusion and exclusion criteria, extracted data, and evaluated the bias of the included studies. RevMan 5.3 analysis software was used for meta-analysis.

Results

A total of 18 RCTs involving 5 autoimmune diseases were included. The 5 autoimmune disease were rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), inflammatory bowel disease, ankylosing spondylitis, and multiple sclerosis. For RA, the current randomized controlled trials (RCTs) still believe that stem cell transplantation may reduce disease activity, improve the clinical symptoms (such as DAS28), and the percentage of CD4+CD 25+Foxp3+Tregs in the response group increased and the percentage of CD4+IL-17A+Th17 cells decreased. The total clinical effective rate of RA is 54%. For SLE, the results showed that mesenchymal stem cell transplantation may improve SLEDAI [-2.18 (-3.62, -0.75), P = 0.003], urine protein [-0.93 (-1.04, -0.81), P < 0.00001], and complement C3 [0.31 (0.19, 0.42), P < 0.00001]. For inflammatory bowel disease, the results showed that mesenchymal stem cell transplantation may improve clinical efficacy [2.50 (1.07, 5.84), P = 0.03]. For ankylosing spondylitis, MSC treatment for 6 months may increase the total effective rate; reduce erythrocyte sedimentation rate, intercellular adhesion molecules, and serum TNF-α; and improve pain and activity. For multiple sclerosis, the current research results are still controversial, so more RCTs are needed to amend or confirm the conclusions. No obvious adverse events of mesenchymal stem cell transplantation were found in all RCTs.

Conclusion

MSCs have a certain effect on different autoimmune diseases, but more RCTs are needed to further modify or confirm the conclusion.

The Potential Use of Mesenchymal Stem Cells and Their Derived Exosomes for Orthopedic Diseases Treatment

Musculoskeletal disorders (MSDs) are conditions that can affect muscles, bones, and joints. These disorders are very painful and severely limit patients' mobility and are more common in the elderly. MSCs are multipotent stem cells isolated from embryonic (such as the umbilical cord) and mature sources (such as adipose tissue and bone marrow). These cells can differentiate into various cells such as osteoblasts, adipocytes, chondrocytes, NP-like cells, Etc. Due to MSC characteristics such as immunomodulatory properties, ability to migrate to the site of injury, recruitment of cells involved in repair, production of growth factors, and large amount production of extracellular vesicles, these cells have been used in many regenerative-related medicine studies. Also, MSCs produce different types of EVs, such as exosomes, to the extracellular environment. Exosomes reflect MSCs' characteristics and do not have cell therapy-associated problems because they are cell-free. These vesicles carry proteins, nucleic acids, and lipids to the host cell and change their function. This review focuses on MSCs and MSCs exosomes' role in repairing dense connective tissues such as tendons, cartilage, invertebrate disc, bone fracture, and osteoporosis treatment.

The Role of Low-Level Laser Therapy in the Treatment of Multiple Sclerosis: A Review Study

Introduction: Multiple sclerosis (MS) is an autoimmune disease. Inflammatory cells, cytokines and chemokines play a major role in the pathogenesis of the disease. Low-level laser therapy (LLLT) as a photobiostimulation approach could affect a wide range of cellular responses. LLLT inhibits the inflammatory signaling pathway, improves cell viability, inhibits apoptosis, modulates immune responses and induces the production of growth factors. Methods: In this review, we discuss the effect of LLLT on cellular responses and its application in the treatment of MS. Such keywords as "low-level laser therapy", "photobiomodulation" and "multiple sclerosis" were used to find studies related to laser therapy in MS in Google scholar, PubMed and Medline databases. Results: LLLT reduced the inflammatory immune cells and mediators. It also enhanced the regeneration of neurons. Conclusion: Investigations showed that besides current treatment strategies, LLLT could be a promising therapeutic approach for the treatment of MS.

Immunotherapy of multisystem inflammatory syndrome in children (MIS-C) following COVID-19 through mesenchymal stem cells

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new type of coronavirus causing coronavirus 2019 (COVID-19) that was first observed in Wuhan, China, in Dec. 2019. An inflammatory immune response targeting children appeared during the pandemic, which was associated with COVID-19 named multisystem inflammatory syndrome in children (MIS-C). Characteristics of MIS-C include the classic inflammation findings, multi-organ dysfunction, and fever as the cardinal feature. Up to now, no specific therapy has been identified for MIS-C. Currently, considerable progress has been obtained in the MIS-C treatment by cell therapy, specially Mesenchymal stem cells (MSCs). Unique properties have been reported for MSCs, such as various resources for purification of cell, high proliferation, self-renewal, non-invasive procedure, tissue regenerator, multidirectional differentiation, and immunosuppression. As indicated by a recent clinical research, MSCs have the ability of reducing disease inflammation and severity in children with MIS-C. In the present review study, the benefits and characteristics of MSCs and exosomes are discussed for treating patients with MIS-C.

Efficacy of mesenchymal stem cell transplantation therapy for type 1 and type 2 diabetes mellitus: a meta-analysis

BACKGROUND

This meta-analysis was first conducted to evaluate the efficacy and safety of transplantation of mesenchymal stem cells in the treatment of type 1 and type 2 diabetes mellitus (T1DM and T2DM).

METHODS

We systematically searched PubMed, ScienceDirect, Google Scholar, CNKI, EMBASE, Web of Science, MEDLINE, and the Cochrane Library for studies published from the establishment of the databases to November 2020. Two researchers independently screened the identified studies, based on inclusion and exclusion criteria. The combined standard mean difference (SMD) and 95% confidence interval (CI) of data from the included studies were calculated using fixed- or random-effects models.

RESULTS

We included 10 studies in our meta-analysis (4 studies on T1DM and 6 on T2DM, with 239 participants) to examine the efficacy of mesenchymal stem cells (MSCs) therapy in the treatment of diabetes mellitus. According to the pooled estimates, the glycated hemoglobin (HbA1c) level of the MSC-treated group was significantly lower than it was at baseline (mean difference (MD) = -1.51, 95% CI -2.42 to -0.60, P = 0.001). The fasting C-peptide level of the MSC-treated group with T1DM was higher than that of the control group (SMD = 0.89, 95% CI 0.36 to 1.42, P = 0.001), and their insulin requirement was significantly lower than it was at baseline (SMD = -1.14, 95% CI -1.52 to -0.77, P < 0.00001).

CONCLUSION

Transplantation of mesenchymal stem cells has beneficial effects on diabetes mellitus, especially T1DM, and no obvious adverse reactions.

Optimization of oxidative stress for mesenchymal stromal/stem cell engraftment, function and longevity

Mesenchymal stromal/stem cells (MSCs) are multipotent cells that possess great potential as a cellular therapeutic based on their ability to differentiate to different lineages and to modulate immune responses. However, their potential is limited by their low tissue abundance, and thus the need for robust ex vivo expansion prior to their application. This creates its own issues, namely replicative senescence, which could lead to reduced MSC functionality and negatively impact their engraftment. Ex vivo expansion and MSC aging are associated with greater oxidative stress. Therefore, there is great need to identify strategies to reduce oxidative stress in MSCs. This review summarizes the achievements made to date in addressing oxidative stress in MSCs and speculates about interesting avenues of future investigation to solve this critical problem.

Efficacy of mesenchymal stem cell therapy on glucose levels in type 2 diabetes mellitus: A systematic review and meta-analysis

AIMS/INTRODUCTION

In recent years, mesenchymal cellular therapies have received much attention in the treatment of diabetes. In this meta-analysis, we aimed to evaluate the efficacy of mesenchymal stem cell therapy in type 2 diabetes mellitus patients.

MATERIALS AND METHODS

A comprehensive literature search was carried out using PubMed, Scopus, Web of Science and Central databases. A total of 1,721 articles were identified, from which nine full-text clinical trials were qualified to enter the current meta-analysis. The assessment groups included patients with type 2 diabetes, and levels of C-peptide, glycosylated hemoglobin and insulin dose were analyzed before and after mesenchymal stem cell infusion. Data analysis was carried out in Stata version 11, and the Jadad Score Scale was applied for quality assessment.

RESULTS

Changes in levels of C-peptide after mesenchymal stem cell therapy were: standardized mean difference 0.20, 95% confidence interval -0.61 to 1.00, glycosylated hemoglobin levels were: standardized mean difference -1.45, 95% confidence interval -2.10 to -0.79 and insulin dose were: standardized mean difference -1.40, 95% confidence interval -2.88 to 0.09.

CONCLUSIONS

This meta-analysis of prospective studies showed associations between mesenchymal stem cell therapy and control of glucose level in patients with type 2 diabetes.

Psoriatic mesenchymal stem cells stimulate the angiogenesis of human umbilical vein endothelial cells in vitro

OBJECTIVE

To investigate the regulation of psoriatic dermal mesenchymal stem cells (p-DMSCs) in the expression of vascular growth factor (VEGF), and migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro.

METHODS

A co-culture model of HUVECs and dermal mesenchymal stem cells (DMSCs)was used in this study. After 7-day co-culture, changes in expression levels of VEGF mRNA and protein in HUVECs were assessed using RT-PCR and Western Blotting, respectively. Migration and tubular formation of HUVECs were also assessed following co-culture of DMSCs and HUVECs.

RESULTS

In comparison to either HUVECs alone or co-culture of n-DMSCs and HUVECs, co-culture of HUVECs and p-DMSCs significantly increased expression levels of both VEGF mRNA (p < 0.01 vs. HUVECs alone) and protein in HUVECs (p < 0.001 vs. both HUVECs alone and HUVECs co-cultured with n-DMSCs). Moreover, p-DMSCs stimulated HUVEC migration and vascular formation (p < 0.05 vs. both HUVECs alone and co-culture of n-DMSCs and HUVECs).

CONCLUSION

Psoriatic DMSCs can upregulate VEGF expression, and stimulate migration and angiogenesis of HUVECs, suggesting a pathogenic role of p-DMSCs in psoriasis.

Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells from the Tasmanian Devil (Sarcophilus harrisii) Express Immunomodulatory Factors and a Tropism Toward Devil Facial Tumor Cells

Marsupials have long attracted scientific interest because of their unique biological features and their position in mammalian evolution. Mesenchymal stem cells (MSCs) are of considerable research interest in translational medicine due to their immunomodulatory, anti-inflammatory, and regenerative properties. MSCs have been harvested from various tissues in numerous eutherian species; however, there are no descriptions of MSCs derived from a marsupial. In this study, we have generated Tasmanian devil (Sarcophilus harrisii) MSCs from devil induced pluripotent stem cells (iPSCs), thus providing an unlimited source of devil MSCs and circumventing the need to harvest tissues from live animals. Devil iPSCs were differentiated into MSCs (iMSCs) through both embryoid body formation assays (EB-iMSCs) and through inhibition of the transforming growth factor beta/activin signaling pathway (SB-iMSCs). Both EB-iMSCs and SB-iMSCs are highly proliferative and express the MSC-specific surface proteins CD73, CD90, and CD105, in addition to the pluripotency transcription factors OCT4/POU5F1, SOX2, and NANOG. Expression of the marsupial pluripotency factor POU5F3, a paralogue of OCT4/POU5F1, is significantly reduced in association with the transition from pluripotency to multipotency. Devil iMSCs readily differentiate along the adipogenic, osteogenic, and chondrogenic pathways in vitro, confirming their trilineage differentiation potential. Importantly, in vitro teratoma assays confirmed their multipotency, rather than pluripotency, since the iMSCs only formed derivatives of the mesodermal germ layer. Devil iMSCs show a tropism toward medium conditioned by devil facial tumor cells and express a range of immunomodulatory and anti-inflammatory factors. Therefore, devil iMSCs will be a valuable tool for further studies on marsupial biology and may facilitate the development of an MSC-based treatment strategy against Devil Facial Tumor Disease.

Inflammatory bowel disease: Therapeutic limitations and prospective of the stem cell therapy

Inflammatory bowel disease (IBD), consisting primarily of ulcerative colitis and Crohn’s disease, is a group of debilitating auto-immune disorders, which also increases the risk of colitis-associated cancer. However, due to the chronic nature of the disease and inconsistent treatment outcomes of current anti-IBD drugs (e.g., approximately 30% non-responders to anti-TNFα agents), and related serious side effects, about half of all IBD patients (in millions) turn to alternative treatment options. In this regard, mucosal healing is gaining acceptance as a measure of disease activity in IBD patients as recent studies have correlated the success of mucosal healing with improved prognosis. However, despite the increasing clinical realization of the significance of the concept of mucosal healing, its regulation and means of therapeutic targeting remain largely unclear. Here, stem-cell therapy, which uses hematopoietic stem cells or mesenchymal stem cells, remains a promising option. Stem cells are the pluripotent cells with ability to differentiate into the epithelial and/or immune-modulatory cells. The over-reaching concept is that the stem cells can migrate to the damaged areas of the intestine to provide curative help in the mucosal healing process. Moreover, by differentiating into the mature intestinal epithelial cells, the stem cells also help in restoring the barrier integrity of the intestinal lining and hence prevent the immunomodulatory induction, the root cause of the IBD. In this article, we elaborate upon the current status of the clinical management of IBD and potential role of the stem cell therapy in improving IBD therapy and patient’s quality of life.

Calorie restriction promotes remyelination in a Cuprizone-Induced demyelination mouse model of multiple sclerosis

Over the past few decades several attempts have been made to introduce a potential and promising therapy for Multiple sclerosis (MS). Calorie restriction (CR) is a dietary manipulation to reduce calorie intake which has been shown to improve neuroprotection and attenuate neurodegenerative disorders. Here, we evaluated the effect of 33% CR regimen for 4 weeks on the remyelination capacity of Cuprizone (CPZ) induced demyelination in a mouse model of MS. Results showed that CR induced a significant increase in motor coordination and balance performance in CPZ mice. Also, luxol fast blue (LFB) staining showed that CR regimen significantly improved the remyelination in the corpus callosum of CPZ + CR mice compared to the CPZ group. In addition, CR regimen significantly increased the transcript expression levels of BDNF, Sox2, and Sirt1 in the corpus callosum of CPZ mice, while decreasing the p53 levels. Moreover, CR regimen significantly decreased the apoptosis rate. Furthermore, astrogliosis (GFAP + astrocytes) and microgliosis (Iba-1 + microglia) were significantly decreased by CR regimen while oligodendrogenesis (Olig2+) and Sirt1 + cell expression were significantly increased in the corpus callosum of CPZ + CR mice compared to the CPZ group. In conclusion, CR regimen can promote remyelination potential in a CPZ-demyelinating mouse model of MS by increasing oligodendrocyte generation while decreasing their apoptosis.

Therapeutic effects of mesenchymal stem cells on cutaneous leishmaniasis lesions caused by Leishmania major

OBJECTIVES

Leishmania major (L. major) is a cutaneous leishmaniasis causative agent. Current chemotherapeutic methods are not totally effective in treatment of this disease. The immunomodulation and tissue repairing capability of mesenchymal stem cells (MSCs), ease of isolation, detection and in vitro culture, have encouraged biologists to use MSCs for cell therapy in different infections such as cutaneous leishmaniasis.

METHODS

BALB/c mice (6-8 weeks old) were infected with L. major then divided into four groups and treated with MSCs, Glucantime, Glucantime + MSCs, or PBS. Regression of lesions, potency of macrophages for phagocytosis, proliferation of immune cells against Leishmania soluble antigen, reduction of spleen parasite burden and healing of the lesions were evaluated on days 10, 20 and 30 of treatment.

RESULTS

The results indicated that the mice intralesionally injected with MSCs showed significant regression in the lesions produced by L. major by day 30. Proliferation of splenocytes stimulated with SLA (soluble leishmania antigen) in vitro in MSC-treated mice on day 20 was significantly higher than in the other groups. The potency of phagocytosis in macrophages of mice treated with MSCs was significantly higher by day 30 and healing of the lesions in this group of mice showed more progress on histopathological examinations. Spleen parasite burden showed significant reduction in the mice treated with Glucantime + MSCs by day 30.

CONCLUSIONS

The results showed that including MSCs in treatment of cutaneous leishmaniasis caused by L. major is a promising approach.

The role of B cells in the immunopathogenesis of multiple sclerosis

There is ongoing debate on how B cells contribute to the pathogenesis of multiple sclerosis (MS). The success of B-cell targeting therapies in MS highlighted the role of B cells, particularly the antibody-independent functions of these cells such as antigen presentation to T cells and modulation of the function of T cells and myeloid cells by secreting pathogenic and/or protective cytokines in the central nervous system. Here, we discuss the role of different antibody-dependent and antibody-independent functions of B cells in MS disease activity and progression proposing new therapeutic strategies for the optimization of B-cell targeting treatments.

Mesenchymal Stromal Cells Protect the Blood-Brain Barrier, Reduce Astrogliosis, and Prevent Cognitive and Behavioral Alterations in Surviving Septic Mice

OBJECTIVES

Survivors of sepsis are frequently left with significant cognitive and behavioral impairments. These complications derive from nonresolving inflammation that persists following hospital discharge. To date, no study has investigated the effects of mesenchymal stromal cell therapy on the blood-brain barrier, astrocyte activation, neuroinflammation, and cognitive and behavioral alterations in experimental sepsis.

DESIGN

Prospective, randomized, controlled experimental study.

SETTING

Government-affiliated research laboratory.

SUBJECTS

Male Swiss Webster mice (n = 309).

INTERVENTIONS

Sepsis was induced by cecal ligation and puncture; sham-operated animals were used as control. All animals received volume resuscitation (1 mL saline/mouse subcutaneously) and antibiotics (meropenem 10 mg/kg intraperitoneally at 6, 24, and 48 hours). Six hours after surgery, mice were treated with mesenchymal stromal cells IV (1 × 10 cells in 0.05 mL of saline/mouse) or saline (0.05 mL IV).

MEASUREMENTS AND MAIN RESULTS

At day 1, clinical score and plasma levels of inflammatory mediators were increased in cecal ligation and puncture mice. Mesenchymal stromal cells did not alter clinical score or survival rate, but reduced levels of systemic interleukin-1β, interleukin-6, and monocyte chemoattractant protein-1. At day 15, survivor mice completed a battery of cognitive and behavioral tasks. Cecal ligation and puncture mice exhibited spatial and aversive memory deficits and anxiety-like behavior. These effects may be related to increased blood-brain barrier permeability, with altered tight-junction messenger RNA expression, increased brain levels of inflammatory mediators, and astrogliosis (induced at day 3). Mesenchymal stromal cells mitigated these cognitive and behavioral alterations, as well as reduced blood-brain barrier dysfunction, astrocyte activation, and interleukin-1β, interleukin-6, tumor necrosis factor-α, and interleukin-10 levels in vivo. In cultured primary astrocytes stimulated with lipopolysaccharide, conditioned media from mesenchymal stromal cells reduced astrogliosis, interleukin-1β, and monocyte chemoattractant protein-1, suggesting a paracrine mechanism of action.

CONCLUSIONS

In mice who survived experimental sepsis, mesenchymal stromal cell therapy protected blood-brain barrier integrity, reduced astrogliosis and neuroinflammation, as well as improved cognition and behavior.

Manipulated Mesenchymal Stem Cells Applications in Neurodegenerative Diseases

Mesenchymal stem cells (MSCs) are multipotent stem cells that have multilinear differentiation and self-renewal abilities. These cells are immune-privileged as they express no or low level of class-II major histocompatibility complex (MHC-II) and other costimulatory molecules. Having neuroprotective and regenerative properties, MSCs can be used to ameliorate several intractable neurodegenerative disorders by affecting both innate and adaptive immune systems. Several manipulations like pretreating MSCs with different conditions or agents, and using molecules derived from MSCs or genetically manipulating them, are the common and practical ways that can be used to strengthen MSCs survival and potency. Improved MSCs can have significantly enhanced impacts on diseases compared to MSCs not manipulated. In this review, we describe some of the most important manipulations that have been exerted on MSCs to improve their therapeutic functions and their applications in ameliorating three prevalent neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, and Huntington's disease.

Regulatory effect of rat bone marrow mesenchymal stem cells on Treg/Th17 immune balance in vitro

Bone marrow mesenchymal stem cells (BM-MSCs) regulate the balance between regulatory T cells (Tregs) and T helper 17 (Th17) cells. However, the role of different factors on BM-MSCs-mediated regulation of the Treg/Th17 balance is unknown. BM-MSCs and CD4⁺ T lymphocytes were co-cultured with various treatments. The ratio of Treg/Th17 cells was calculated and the expression of different cytokines was measured. BM-MSCs were found to have a proliferative effect on Th17 cells at a basal concentration and at a 2-fold increase in the number of BM-MSCs. However, when the number of BM-MSCs used was increased 4-fold, they had an inhibitory effect on the Th17 cells. The effect of BM-MSCs on Tregs was inhibited by the addition of tacrolimus but not rapamycin. The effect of BM-MSCs on Th17 cells was inhibited by rapamycin. Additionally, the effect of BM-MSCs on Tregs were inhibited by the addition of a transforming growth factor-β (TGF-β) blocker, whereas these TGF-β-blockers had no effect on Th17 cells. Addition of an interleukin (IL)-2 blocker reduced the proportion of Th17 cells when co-cultured with a high number of MSCs compared with the low concentration group and the proportion of Treg cells was significantly decreased when cells were treated with an IL-2 blocker compared with the control group. Together, these results showed the varying effects of MSCs on the ratio of Treg/Th17, its dependence on the number of MSCs and the effects of cytokines in inducing these changes in the balance.

Positive role of calcium phosphate ceramics regulated inflammation in the osteogenic differentiation of mesenchymal stem cells

Recently, researches have confirmed the crucial role of inflammatory response in Ca-P ceramic-induced osteogenesis, however, the underlying mechanism has not yet been fully understood. In this study, BCP and β-TCP ceramics were used as material models to investigate the effect of physicochemical properties on inflammatory response in vitro. The results showed that BCP and β-TCP could support macrophages attachment, proliferation, and spreading favorably, as well as promote gene expressions of inflammatory related cytokines (IL-1, IL-6, MCP-1, and TNF-α) and growth factors (TGF-β, FGF, PDGF, VEGF, IGF, and EGF). BCP showed a facilitating function on the gene expressions earlier than β-TCP. Further coculture experiments performed in vitro demonstrated that the CMs containing various increased cytokines for macrophages pre-culture could significantly promote MSCs osteogenic differentiation, which was confirmed by the gene expressions of osteogenic specific markers and the intracellular OCN product accumulation under the stimulation of BCP and β-TCP ceramics. Further evidence was found from the formation of mineralized nodules in BCM and TCM. In addition, this study showed a concise relationship between Ca-P ceramic induced inflammation and its osteoinductivity that the increased cytokines and growth factors from macrophages could promote MSCs osteogenic differentiation.

Cell-based Therapy for Perianal Fistulising Crohn's Disease

BACKGROUND

The management of complex perianal fistulas in Crohn's disease (CD) represents a challenge for patients, gastroenterologists and colorectal surgeons. There are clear limitations with current medical and surgical options, and healing rates remain far from what is expected. A multidisciplinary approach with optimized medical therapy, usually anti-TNF agents, associated with setons and additional surgical techniques is currently the best strategy to aim fistula healing.

METHODS

A comprehensive review of the literature was conducted on the use of mesenchymal stem cells (MSCs).

RESULTS

The use of mesenchymal stem cells (MSCs) has recently emerged as a promising new therapeutic strategy for complex fistulas in CD patients. This review summarizes the evidence of the use of MSCs in complex CD fistulas, by exploring in detail the types of cells that can be used and their modes of delivery. Additionally, the results of the most recent phase III randomized trial with local MSCs injection are described, and future challenges of this therapeutic option are discussed.

CONCLUSION

The use of MSCs represents hope for better outcomes in patients with CD-related perianal fistulas. More research in the field will help to position this specific therapy in treatment algorithms.

Insulin-Producing Cell Transplantation Platform for Veterinary Practice

Diabetes mellitus (DM) remains a global concern in both human and veterinary medicine. Type I DM requires prolonged and consistent exogenous insulin administration to address hyperglycemia, which can increase the risk of diabetes complications such as retinopathy, nephropathy, neuropathy, and heart disorders. Cell-based therapies have been successful in human medicine using the Edmonton protocol. These therapies help maintain the production of endogenous insulin and stabilize blood glucose levels and may possibly be adapted to veterinary clinical practice. The limited number of cadaveric pancreas donors and the long-term use of immunosuppressive agents are the main obstacles for this protocol. Over the past decade, the development of potential therapies for DM has mainly focused on the generation of effective insulin-producing cells (IPCs) from various sources of stem cells that can be transplanted into the body. Another successful application of stem cells in type I DM therapies is transplanting generated IPCs. Encapsulation can be an alternative strategy to protect IPCs from rejection by the body due to their immunoisolation properties. This review summarizes current concepts of IPCs and encapsulation technology for veterinary clinical application and proposes a potential stem-cell-based platform for veterinary diabetic regenerative therapy.

Targeting Purinergic Signaling and Cell Therapy in Cardiovascular and Neurodegenerative Diseases

Extracellular purines exert several functions in physiological and pathophysiological mechanisms. ATP acts through P2 receptors as a neurotransmitter and neuromodulator and modulates heart contractility, while adenosine participates in neurotransmission, blood pressure, and many other mechanisms. Because of their capability to differentiate into mature cell types, they provide a unique therapeutic strategy for regenerating damaged tissue, such as in cardiovascular and neurodegenerative diseases. Purinergic signaling is pivotal for controlling stem cell differentiation and phenotype determination. Proliferation, differentiation, and apoptosis of stem cells of various origins are regulated by purinergic receptors. In this chapter, we selected neurodegenerative and cardiovascular diseases with clinical trials using cell therapy and purinergic receptor targeting. We discuss these approaches as therapeutic alternatives to neurodegenerative and cardiovascular diseases. For instance, promising results were demonstrated in the utilization of mesenchymal stem cells and bone marrow mononuclear cells in vascular regeneration. Regarding neurodegenerative diseases, in general, P2X7 and A_2A receptors mostly worsen the degenerative state. Stem cell-based therapy, mainly through mesenchymal and hematopoietic stem cells, showed promising results in improving symptoms caused by neurodegeneration. We propose that purinergic receptor activity regulation combined with stem cells could enhance proliferative and differentiation rates as well as cell engraftment.

Gene Therapy Approaches in an Autoimmune Demyelinating Disease: Multiple Sclerosis

Multiple Sclerosis (MS) is the most common autoimmune demyelinating disease of the Central Nervous System (CNS). It is a multifactorial disease which develops in an immune-mediated way under the influences of both genetic and environmental factors. Demyelination is observed in the brain and spinal cord leading to neuro-axonal damage in patients with MS. Due to the infiltration of different immune cells such as T-cells, B-cells, monocytes and macrophages, focal lesions are observed in MS. Currently available medications treating MS are mainly based on two strategies; i) to ease specific symptoms or ii) to reduce disease progression. However, these medications tend to induce different adverse effects with limited therapeutic efficacy due to the protective function of the blood-brain barrier. Therefore, researchers have been working for the last four decades to discover better solutions by introducing gene therapy approaches in treating MS generally by following three strategies, i) prevention of specific symptoms, ii) halt or reverse disease progression and iii) heal CNS damage by promoting remyelination and axonal repair. In last two decades, there have been some remarkable successes of gene therapy approaches on the experimental mice model of MS - experimental autoimmune encephalomyelitis (EAE) which suggests that it is not far that the gene therapy approaches would start in human subjects ensuring the highest levels of safety and efficacy. In this review, we summarised the gene therapy approaches attempted in different animal models towards treating MS.

Enhancing Mesenchymal Stromal Cell Immunomodulation for Treating Conditions Influenced by the Immune System

Mesenchymal stromal cells (MSCs), formerly known as mesenchymal stem cells, are nonhematopoietic multipotent cells and are emerging worldwide as the most clinically used and promising source for allogeneic cell therapy. MSCs, initially obtained from bone marrow, can be derived from several other tissues, such as adipose tissue, placenta, and umbilical cord. Diversity in tissue sourcing and manufacturing procedures has significant effects on MSC products. However, in 2006, a minimal set of standard criteria has been issued by the International Society of Cellular Therapy for defining derived MSCs. These include adherence to plastic in conventional culture conditions, particular phenotype, and multilineage differentiation capacity in vitro. Moreover, MSCs have trophic capabilities, a high in vitro self-renewal ability, and immunomodulatory characteristics. Thus, immunosuppressive treatment with MSCs has been proposed as a potential therapeutic alternative for conditions in which the immune system cells influence outcomes, such as inflammatory and autoimmune diseases. The precise mechanism by which MSCs affect functions of most immune effector cells is not completely understood but involves direct contact with immune cells, soluble mediators, and local microenvironmental factors. Recently, it has been shown that their homeostatic resting state requires activation, which can be achieved in vitro with various cytokines, including interferon-γ. In the present review, we focus on the suppressive effect that MSCs exert on the immune system and highlight the significance of in vitro preconditioning and its use in preclinical studies. We discuss the clinical aspects of using MSCs as an immunomodulatory treatment. Finally, we comment on the risk of interfering with the immune system in regard to cancer formation and development.

Mesenchymal Stem Cells for Perianal Crohn's Disease

Perianal fistulizing Crohn’s disease (PFCD) is associated with significant morbidity and might negatively impact the quality of life of CD patients. In the last two decades, the management of PFCD has evolved in terms of the multidisciplinary approach involving gastroenterologists and colorectal surgeons. However, the highest fistula healing rates, even combining surgical and anti-TNF agents, reaches 50% of treated patients. More recently, the administration of mesenchymal stem cells (MSCs) have shown notable promising results in the treatment of PFCD. The aim of this review is to describe the rationale and the possible mechanism of action of MSC application for PFCD and the most recent results of randomized clinical trials. Furthermore, the unmet needs of the current administration process and the expected next steps to improve the outcomes will be addressed.

Human ES-derived MSCs correct TNF-α-mediated alterations in a blood-brain barrier model

Background

Immune cell trafficking into the CNS is considered to contribute to pathogenesis in MS and its animal model, EAE. Disruption of the blood–brain barrier (BBB) is a hallmark of these pathologies and a potential target of therapeutics. Human embryonic stem cell-derived mesenchymal stem/stromal cells (hES-MSCs) have shown superior therapeutic efficacy, compared to bone marrow-derived MSCs, in reducing clinical symptoms and neuropathology of EAE. However, it has not yet been reported whether hES-MSCs inhibit and/or repair the BBB damage associated with neuroinflammation that accompanies EAE.

Methods

BMECs were cultured on Transwell inserts as a BBB model for all the experiments. Disruption of BBB models was induced by TNF-α, a pro-inflammatory cytokine that is a hallmark of acute and chronic neuroinflammation.

Results

Results indicated that hES-MSCs reversed the TNF-α-induced changes in tight junction proteins, permeability, transendothelial electrical resistance, and expression of adhesion molecules, especially when these cells were placed in direct contact with BMEC.

Conclusions

hES-MSCs and/or products derived from them could potentially serve as novel therapeutics to repair BBB disturbances in MS.

Electronic supplementary material

The online version of this article (10.1186/s12987-019-0138-5) contains supplementary material, which is available to authorized users.

Stem cell therapy for perianal Crohn's

PURPOSE OF REVIEW

Perianal Crohn's disease is a morbid and disabling condition, notoriously difficult to successfully treat with conventional medical and surgical therapies. Mesenchymal stem cells (MSCs) are an emerging novel therapy for perianal Crohn's disease.

RECENT FINDINGS

Over 300 patients with perianal Crohn's disease have now been treated with MSCs in the context of clinical trials. All trials have demonstrated safety, and efficacy superior to conventional therapy with biologics and surgical intervention. This was consistent despite the heterogeneity in study protocols including variability in cell dosing, mode of delivery, repeat dosing, and allogeneic versus autologous donors. Sustained healing to 1 year has also been demonstrated in a recent extension of the largest phase III study confirming superior efficacy of MSCs to placebo at 1-year follow-up. However, several outstanding questions regarding the use of MSCs for perianal Crohn's disease remain, which, if answered, could enhance MSCs' treatment efficacy. These include defining the optimal MSC donor, optimal MSC source (e.g., bone marrow versus adipose tissue), investigating a potential alloimmune response following allogeneic cellular delivery, and determining the optimal mode for MSC delivery. In addition to these unanswered questions, significant challenges in the required infrastructure and cost required for cell-based therapies may drive future research toward identifying novel acellular therapies.

SUMMARY

Novel regenerative therapies offer promising new treatment options for perianal Crohn's disease, without the risk of opportunistic infection seen with biologics and incontinence with surgical techniques. Future research will help define the optimal MSC product and treatment protocol, and may even expand our horizon of regenerative medicine into acellular therapy as well as cell-based therapies.

Multipotent fetal-derived Cdx2 cells from placenta regenerate the heart

There is a critical need to identify accessible stem cells that can form spontaneously beating cardiomyocytes (CMs) and enable regeneration. Here, we establish that intravenous delivery of placental Cdx2 cells resulted in directed homing, sustained engraftment, and differentiation into CMs and vascular cells in damaged hearts, significantly improving cardiac function. This study unveils a distinctive functional significance of Cdx2 beyond its established role in embryonic patterning. Therapeutic use of Cdx2 cells may represent a vital advance, as these cells are multipotent and immunologically naive, with a unique proteome, compared with embryonic stem cells. Moreover, they exhibit the ability to selectively home to sites of injury. These characteristics pave the way for novel allogeneic stem cell therapy for cardiac disease.

The extremely limited regenerative potential of adult mammalian hearts has prompted the need for novel cell-based therapies that can restore contractile function in heart disease. We have previously shown the regenerative potential of mixed fetal cells that were naturally found migrating to the injured maternal heart. Exploiting this intrinsic mechanism led to the current hypothesis that Caudal-type homeobox-2 (Cdx2) cells in placenta may represent a novel cell type for cardiac regeneration. Using a lineage-tracing strategy, we specifically labeled fetal-derived Cdx2 cells with enhanced green fluorescent protein (eGFP). Cdx2-eGFP cells from end-gestation placenta were assayed for cardiac differentiation in vitro and in vivo using a mouse model of myocardial infarction. We observed that these cells differentiated into spontaneously beating cardiomyocytes (CMs) and vascular cells in vitro, indicating multipotentiality. When administered via tail vein to infarcted wild-type male mice, they selectively and robustly homed to the heart and differentiated to CMs and blood vessels, resulting in significant improvement in contractility as noted by MRI. Proteomics and immune transcriptomics studies of Cdx2-eGFP cells compared with embryonic stem (ES) cells reveal that they appear to retain “stem”-related functions of ES cells but exhibit unique signatures supporting roles in homing and survival, with an ability to evade immune surveillance, which is critical for cell-based therapy. Cdx2-eGFP cells may potentially represent a therapeutic advance in allogeneic cell therapy for cardiac repair.

The Potential of Stem Cell Therapy to Repair White Matter Injury in Preterm Infants: Lessons Learned From Experimental Models

Diffuse white matter injury (dWMI) is a major cause of morbidity in the extremely preterm born infant leading to life-long neurological impairments, including deficits in cognitive, motor, sensory, psychological, and behavioral functioning. At present, no treatment options are clinically available to combat dWMI and therefore exploration of novel strategies is urgently needed. In recent years, the pathophysiology underlying dWMI has slowly started to be unraveled, pointing towards the disturbed maturation of oligodendrocytes (OLs) as a key mechanism. Immature OL precursor cells in the developing brain are believed to be highly sensitive to perinatal inflammation and cerebral oxygen fluctuations, leading to impaired OL differentiation and eventually myelination failure. OL lineage development under normal and pathological circumstances and the process of (re)myelination have been studied extensively over the years, often in the context of other adult and pediatric white matter pathologies such as stroke and multiple sclerosis (MS). Various studies have proposed stem cell-based therapeutic strategies to boost white matter regeneration as a potential strategy against a wide range of neurological diseases. In this review we will discuss experimental studies focusing on mesenchymal stem cell (MSC) therapy to reduce white matter injury (WMI) in multiple adult and neonatal neurological diseases. What lessons have been learned from these previous studies and how can we translate this knowledge to application of MSCs for the injured white matter in the preterm infant? A perspective on the current state of stem cell therapy will be given and we will discuss different important considerations of MSCs including cellular sources, timing of treatment and administration routes. Furthermore, we reflect on optimization strategies that could potentially reinforce stem cell therapy, including preconditioning and genetic engineering of stem cells or using cell-free stem cell products, to optimize cell-based strategy for vulnerable preterm infants in the near future.

Mesenchymal Stem Cells from Chronic Pancreatitis Patients Show Comparable Potency Compared to Cells from Healthy Donors

Mesenchymal stem cells (MSCs) are proven to be beneficial in islet transplantation, suggesting a potential therapeutic role of them in total pancreatectomy with islet autotransplantation (TP-IAT) for chronic pancreatitis (CP) patients. We investigated whether MSCs derived from CP patients are suitable for use in autologous cell therapy. MSCs from healthy donors (H-MSCs) and CP patients (CP-MSCs) were studied for phenotype, colony formation potential, multilineage differentiation ability, proliferation, senescence, secretory characters, and immunosuppressive functions. The potential protective effect of CP-MSCs was evaluated on hypoxia-induced islet cell death. Cell surface markers were similar between H-MSCs and CP-MSCs, as well as the ability of colony formation, multilineage differentiation, secretion of vascular endothelial growth factor and transforming growth factor (TGF-β), senescence, and inhibition of T cells proliferation in vitro. We found that growth differentiation factor 6 and hepatocyte growth factor (HGF) were significantly downregulated, whereas TGFβ and matrix metalloproteinase-2 were significantly upregulated in CP-MSCs compared with H-MSCs, among 84 MSC-related genes investigated in this study. MSCs from CP patients secreted less HGF, compared with the H-MSCs. A higher interferon-γ-induced indoleamine 2,3-dioxygenase expression was observed in CP-MSCs compared to H-MSCs. Moreover, CP-MSCs prevented hypoxia-induced β cell deaths to a similar extent as H-MSCs. Regardless of moderate difference in gene expression, CP-MSCs possess similar immunomodulatory and prosurvival functions to H-MSCs, and may be suitable for autologous cell therapy in CP patients undergoing TP-IAT. Stem Cells Translational Medicine 2019;8:418-429.

Effect of Comedications and Endotoxins on Mesenchymal Stem Cell Secretomes, Migratory and Immunomodulatory Capacity

Mesenchymal stem cells (MSCs) are becoming an increasingly popular therapeutic option among patients with a broad range of ailments to modulate immunity and induce regeneration. The majority of patients receiving these MSC therapies are on concurrent medication or have ongoing infection. In the present study, we examined the effect of immunosuppressive drugs and lipopolysaccharides (LPS)/endotoxins on the secretory profile, migration towards site of injury, and suppression of lymphocyte proliferation of bone marrow-derived MSCs (BMSCs). Generally, LPS coculture augmented the secretory capacity of BMSCs while exposure to immunosuppressive drugs resulted primarily in no change or attenuated secretion, with some cases of increased secretion, dependent on the cytokine assayed. Among the immunosuppressants evaluated, Hydrocortisone had the most widespread inhibitory effect, while LPS from E. coli O111:B4 had the most potent stimulatory effect. In addition, we also showed that Hydrocortisone or LPS from E. coli O111:B4 affected the migratory and immunosuppressive capacity of BMSCs. Following simulation with Hydrocortisone, BMSC migration was attenuated, and immunosuppressive capacity against T cell proliferation was enhanced, however, the opposite effects were seen with LPS from E. coli O111:B4. Our data suggests that the clinical outcomes of MSC-based therapy are affected by the use of immunosuppressive medication or the presence of endotoxemia in patients.

Stem Cell Therapies for Inflammatory Bowel Disease

PURPOSE OF REVIEW

Stem cell therapies have demonstrated safety and efficacy in the treatment of perianal Crohn's disease as compared to conventional therapy. Thus, an understanding of their place in the treatment algorithm for inflammatory bowel disease has become imperative as we move into an era of regenerative medicine.

RECENT FINDINGS

There have now been over a dozen clinical trials highlighting stem cells as a useful therapeutic in Crohn's disease. Due to the success in the local treatment for perianal Crohn's disease, investigation is continuing in the space of targeted systemic delivery for the treatment of luminal disease. As we increase the number of patients treated in clinical trials, it is imperative to define the optimal cell donor, optimize treatment dosing and retreatment protocols, and understand methods for safely targeting and treating intraluminal disease.

Stem Cells as Potential Targets of Polyphenols in Multiple Sclerosis and Alzheimer's Disease

Alzheimer's disease (AD) and multiple sclerosis are major neurodegenerative diseases, which are characterized by the accumulation of abnormal pathogenic proteins due to oxidative stress, mitochondrial dysfunction, impaired autophagy, and pathogens, leading to neurodegeneration and behavioral deficits. Herein, we reviewed the utility of plant polyphenols in regulating proliferation and differentiation of stem cells for inducing brain self-repair in AD and multiple sclerosis. Firstly, we discussed the genetic, physiological, and environmental factors involved in the pathophysiology of both the disorders. Next, we reviewed various stem cell therapies available and how they have proved useful in animal models of AD and multiple sclerosis. Lastly, we discussed how polyphenols utilize the potential of stem cells, either complementing their therapeutic effects or stimulating endogenous and exogenous neurogenesis, against these diseases. We suggest that polyphenols could be a potential candidate for stem cell therapy against neurodegenerative disorders.

Interspecies Incompatibilities Limit the Immunomodulatory Effect of Human Mesenchymal Stromal Cells in the Rat

Mesenchymal stem/stromal cells (MSC) are an immunomodulatory cell population which are under preclinical and clinical investigation for a number of inflammatory conditions including transplantation. In this study, a well-established rat corneal transplantation model was used to test the ability of human MSC to prolong corneal allograft rejection-free survival using a pre-transplant intravenous infusion protocol previously shown to be efficacious with allogeneic rat MSC. Surprisingly, pre-transplant administration of human MSC had no effect on corneal allograft survival. In vitro, human MSC failed to produce nitric oxide and upregulate IDO and, as a consequence, could not suppress rat T-cell proliferation. Furthermore, human MSC were not activated by rat pro-inflammatory cytokines. Thus, interspecies incompatibility in cytokine signaling leading to failure of MSC licensing may explain the lack of in vivo efficacy of human MSC in a rat tissue allotransplant model. Interspecies incompatibilities should be taken into consideration when interpreting preclinical data efficacy data in the context of translation to clinical trial. Stem Cells 2018;36:1210-1215.

PPAR-δ Agonist With Mesenchymal Stem Cells Induces Type II Collagen-Producing Chondrocytes in Human Arthritic Synovial Fluid

Osteoarthritis (OA) is an inflammatory joint disease characterized by degeneration of articular cartilage within synovial joints. An estimated 27 million Americans suffer from OA, and the population is expected to reach 67 million in the United States by 2030. Thus, it is urgent to find an effective treatment for OA. Traditional OA treatments have no disease-modifying effect, while regenerative OA therapies such as autologous chondrocyte implantation show some promise. Nonetheless, current regenerative therapies do not overcome synovial inflammation that suppresses the differentiation of mesenchymal stem cells (MSCs) to chondrocytes and the expression of type II collagen, the major constituent of functional cartilage. We discovered a synergistic combination that overcame synovial inflammation to form type II collagen-producing chondrocytes. The combination consists of peroxisome proliferator–activated receptor (PPAR) δ agonist, human bone marrow (hBM)-derived MSCs, and hyaluronic acid (HA) gel. Interestingly, those individual components showed their own strong enhancing effects on chondrogenesis. GW0742, a PPAR-δ agonist, greatly enhanced MSC chondrogenesis and the expression of type II collagen and glycosaminoglycan (GAG) in hBM-MSC-derived chondrocytes. GW0742 also increased the expression of transforming growth factor β that enhances chondrogenesis and suppresses cartilage fibrillation, ossification, and inflammation. HA gel also increased MSC chondrogenesis and GAG production. However, neither GW0742 nor HA gel could enhance the formation of type II collagen-producing chondrocytes from hBM-MSCs within human OA synovial fluid. Our data demonstrated that the combination of hBM-MSCs, PPAR-δ agonist, and HA gel significantly enhanced the formation of type II collagen-producing chondrocytes within OA synovial fluid from 3 different donors. In other words, the novel combination of PPAR-δ agonist, hBM-MSCs, and HA gel can overcome synovial inflammation to form type II collagen cartilage within human OA synovial fluid. This novel articularly injectable formula could improve OA treatment in the future clinical application.

Stem Cell Therapy for Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory, autoimmune, and neurodegenerative disease of the central nervous system (CNS). It is characterized by demyelination and neuronal loss that is induced by attack of autoreactive T cells to the myelin sheath and endogenous remyelination failure, eventually leading to functional neurological disability. Although recent evidence suggests that MS relapses are induced by environmental and exogenous triggers such as viral infections in a genetic background, its very complex pathogenesis is not completely understood. Therefore, the efficiency of current immunosuppression-based therapies of MS is too low, and emerging disease-modifying immunomodulatory agents such as fingolimod and dimethyl fumarate cannot stop progressive neurodegenerative process. Thus, the cell replacement therapy approach that aims to overcome neuronal cell loss and remyelination failure and to increase endogenous myelin repair capacity is considered as an alternative treatment option. A wide variety of preclinical studies, using experimental autoimmune encephalomyelitis model of MS, have recently shown that grafted cells with different origins including mesenchymal stem cells (MSCs), neural precursor and stem cells, and induced-pluripotent stem cells have the ability to repair CNS lesions and to recover functional neurological deficits. The results of ongoing autologous hematopoietic stem cell therapy studies, with the advantage of peripheral administration to the patients, have suggested that cell replacement therapy is also a feasible option for immunomodulatory treatment of MS. In this chapter, we overview cell sources and applications of the stem cell therapy for treatment of MS. We also discuss challenges including those associated with administration route, immune responses to grafted cells, integration of these cells to existing neural circuits, and risk of tumor growth. Finally, future prospects of stem cell therapy for MS are addressed.