Immunoregulation by mesenchymal stem cells: biological aspects and clinical applications. J Immunol Res. 2015;2015:394917. [PMID: 25961059 PMCID: PMC4417567 DOI: 10.1155/2015/394917]

The potential therapeutic effect of human umbilical cord mesenchymal stem cell-derived exosomes in bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a chronic lung disease of preterm infants, with its incidence rising due to improved survival rates of these infants. BPD results from a combination of prenatal and postnatal factors, such as mechanical ventilation, oxygen toxicity, and infections, all of which significantly impact the prognosis and growth of affected infants. Current treatment options for BPD are largely supportive and do not address the underlying pathology. Exosomes are cell-derived bilayer-enclosed membrane structures enclosing proteins, lipids, RNAs, growth factors, cytokines and metabolites. They have become recognized as crucial regulators of intercellular communication in various physiological and pathological processes. Previous studies have revealed the therapeutic potential of human umbilical cord mesenchymal stem cells-derived exosomes (HUCMSCs-Exos) in promoting tissue repair and regeneration. Therefore, HUCMSCs-Exos maybe a promising and effective therapeutic modality for BPD. In this review, we firstly provide a comprehensive overview of BPD, including its etiology and the mechanisms of lung injury. Then we detail the isolation, characterization, and contents of HUCMSCs-Exos, and discuss their potential mechanisms of HUCMSCs-Exos in BPD treatment. Additionally, we summarize current clinical trials and discuss the challenges in translating these findings from bench to bedside. This review aims to lay the groundwork for future clinical applications of HUCMSCs-Exos in treating BPD.

Perspectives on Stem Cell Therapy in Diabetic Neuropathic Pain

Diabetes mellitus-related morbidity and mortality are primarily caused by long-term complications such as retinopathy, nephropathy, cardiomyopathy, and neuropathy. Diabetic neuropathy (DN) involves the progressive degeneration of axons and nerve fibers due to chronic exposure to hyperglycemia. This metabolic disturbance leads to excessive activation of the glycolytic pathway, inducing oxidative stress and mitochondrial dysfunction, ultimately resulting in nerve damage. There is no specific treatment for painful DN, and new approaches should aim not only to relieve pain but also to prevent oxidative stress and reduce inflammation. Given that existing therapies for painful DN are not effective for diabetic patients, mesenchymal stromal cells (MSCs)-based therapy shows promise for providing immunomodulatory and paracrine regulatory functions. MSCs from various sources can improve neuronal dysfunction associated with DN. Transplantation of MSCs has led to a reduction in hyperalgesia and allodynia, along with the recovery of nerve function in diabetic rats. While the pathogenesis of diabetic neuropathic pain is complex, clinical trials have demonstrated the importance of MSCs in modulating the immune response in diabetic patients. MSCs reduce the levels of inflammatory factors and increase anti-inflammatory cytokines, thereby interfering with the progression of DM. Further investigation is necessary to ensure the safety and efficacy of MSCs in preventing or treating neuropathic pain in diabetic patients.

Evaluation of the therapeutic effect of very small stem cells from peripheral blood on the treatment of Premature Ovarian Failure: A pilot study

OBJECTIVE

Premature ovary failure (POF) is a severe health condition with multiple negative outcomes, which deteriorate a patient's life. The current study aimed to evaluate the therapeutic effect of mesenchymal stem cells (MSCs) derived from peripheral blood in the treatment of women with the POF background.

METHODS

The current study was a pilot study carried-out on women younger than 40 with premature ovarian failure. Study participants underwent 4-months cell therapy using Mesenchymal stem cells extracted from peripheral bloods. Serum level of Follicle-stimulating hormone (FSH), Estradiol (E2), Anti-mullerian hormone (AMH), and Antral follicle count (AFC) were the main investigated outcomes that were assessed at baseline, month two and month four of the very small stem cell intervention.

RESULTS

Average serum level of FSH was 45.0 (12.1) mIU/mL at baseline and continually decreased during the study and reached 33.2 (12.4) mIU/mL in the fourth month. The average AMH level was 0.10 ng/mL prior to the intervention and increased to 0.13 ng/mL in the 2nd month and 0.15 ng/mL in the fourth month. The level E2 was 85.7 (23.6) pg/ml on average at baseline, while the average E2 reduced to 77.2 (25.6) pg/ml in the fourth month. Average number of AFC was 2.0 (0.8) at baseline. We observed a gradual increase in the second month (Mean AFC=2.2) and after four months it increased to 3.1 (1.8) as the highest menstrual restoration and pregnancy was observed in 10% of our study participants.

CONCLUSIONS

MSCs could significantly improve hormone secretion in women with POF. Implantation of MSCs in women with POF background was associated with an increase in AMH and AFC, while it downed the serum level of E2 and FSH. MSCs could also lead to menstrual restoration and pregnancy in women with POF.

Exploring the role of mesenchymal stem cells in modulating immune responses via Treg and Th2 cell activation: insights from mouse model of multiple sclerosis

Multiple sclerosis is a demyelinating neurodegenerative disease, and its animal model, experimental autoimmune encephalomyelitis (EAE), exhibits immunological and clinical similarities. The study aimed to examine mechanisms underlying therapeutic effects of mesenchymal stem cell administration in EAE. C57BL/6 mice were separated into control and treatment groups (T1, T2, and T3); EAE was induced in all animals. Clinical examinations were conducted daily, and on 25th day, animals were sacrificed, and spinal cord was stained for histological analysis. Additionally, spleen cell proliferation assay, assessments of cytokine, and gene expression in both spinal cord and spleen cells were performed. The results indicated a significant reduction in clinical symptoms among treatment groups compared to control group. Histological analyses revealed decreased infiltration of lymphocytes into the spinal cord and reduced demyelinated areas in treatment groups compared to control group. Cytokine production of IL-10, TGF-β, and IL-4 were significantly enhanced and IFN-γ and TNF-α in treatment groups were decreased relative to control group. Also, gene expression of CTLA-4, PD-1, IL-27, and IL-33 indicated a significant increase in treatment groups. The administration of MSCs significantly improved clinical symptoms, attenuated inflammation, and reduced spinal cord demyelination in EAE, suggesting a potential protective effect on disease progression.

Re-establishing immune tolerance in multiple sclerosis: focusing on novel mechanisms of mesenchymal stem cell regulation of Th17/Treg balance

The T-helper 17 (Th17) cell and regulatory T cell (Treg) axis plays a crucial role in the development of multiple sclerosis (MS), which is regarded as an immune imbalance between pro-inflammatory cytokines and the maintenance of immune tolerance. Mesenchymal stem cell (MSC)-mediated therapies have received increasing attention in MS research. In MS and its animal model experimental autoimmune encephalomyelitis, MSC injection was shown to alter the differentiation of CD4+T cells. This alteration occurred by inducing anergy and reduction in the number of Th17 cells, stimulating the polarization of antigen-specific Treg to reverse the imbalance of the Th17/Treg axis, reducing the inflammatory cascade response and demyelination, and restoring an overall state of immune tolerance. In this review, we summarize the mechanisms by which MSCs regulate the balance between Th17 cells and Tregs, including extracellular vesicles, mitochondrial transfer, metabolic reprogramming, and autophagy. We aimed to identify new targets for MS treatment using cellular therapy by analyzing MSC-mediated Th17-to-Treg polarization.

Immunomodulatory effects of extracellular vesicles from mesenchymal stromal cells: Implication for therapeutic approach in autoimmune diseases

Autoimmune disease is characterized by the proliferation of harmful immune cells, inducing tissue inflammation and ultimately causing organ damage. Current treatments often lack specificity, necessitating high doses, prolonged usage, and high recurrence rates. Therefore, the identification of innovative and safe therapeutic strategies is urgently required. Recent preclinical studies and clinical trials on inflammatory and autoimmune diseases have evidenced the immunosuppressive properties of mesenchymal stromal cells (MSCs). Studies have demonstrated that extracellular vesicles (EV) derived from MSCs can mitigate abnormal autoinflammation while maintaining safety within the diseased microenvironment. This study conducted a systematic review to elucidate the crucial role of MSC-EVs in alleviating autoimmune diseases, particularly focusing on their impact on the underlying mechanisms of autoimmune conditions such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and inflammatory bowel disease (IBD). By specifically examining the regulatory functions of microRNAs (miRNAs) derived from MSC-EVs, the comprehensive study aimed to enhance the understanding related to disease mechanisms and identify potential diagnostic markers and therapeutic targets for these diseases.

Impact of STAT-signaling pathway on cancer-associated fibroblasts in colorectal cancer and its role in immunosuppression

Colorectal cancer (CRC) remains one of the most commonly diagnosed and deadliest types of cancer worldwide. CRC displays a desmoplastic reaction (DR) that has been inversely associated with poor prognosis; less DR is associated with a better prognosis. This reaction generates excessive connective tissue, in which cancer-associated fibroblasts (CAFs) are critical cells that form a part of the tumor microenvironment. CAFs are directly involved in tumorigenesis through different mechanisms. However, their role in immunosuppression in CRC is not well understood, and the precise role of signal transducers and activators of transcription (STATs) in mediating CAF activity in CRC remains unclear. Among the myriad chemical and biological factors that affect CAFs, different cytokines mediate their function by activating STAT signaling pathways. Thus, the harmful effects of CAFs in favoring tumor growth and invasion may be modulated using STAT inhibitors. Here, we analyze the impact of different STATs on CAF activity and their immunoregulatory role.

Mesenchymal stem cell-derived exosomes: Characteristics and applications in disease pathology and management

Mesenchymal stem cells (MSCs) possess a role in tissue regeneration and homeostasis because of inherent immunomodulatory capacity and the production of factors that encourage healing. There is substantial evidence that MSCs' therapeutic efficacy is primarily determined by their paracrine function including in cancers. Extracellular vesicles (EVs) are basic paracrine effectors of MSCs that reside in numerous bodily fluids and cell homogenates and play an important role in bidirectional communication. MSC-derived EVs (MSC-EVs) offer a wide range of potential therapeutic uses that exceed cell treatment, while maintaining protocell function and having less immunogenicity. We describe characteristics and isolation methods of MSC-EVs, and focus on their therapeutic potential describing its roles in tissue repair, anti-fibrosis, and cancer with an emphasis on the molecular mechanism and immune modulation and clinical trials. We also explain current understanding and challenges in the clinical applications of MSC-EVs as a cell free therapy.

Developments and Trends of Nanotechnology Application in Sepsis: A Comprehensive Review Based on Knowledge Visualization Analysis

Sepsis, a common life-threatening clinical condition, continues to have high morbidity and mortality rates, despite advancements in management. In response, significant research efforts have been directed toward developing effective strategies. Within this scope, nanotechnology has emerged as a particularly promising field, attracting significant interest for its potential to enhance disease diagnosis and treatment. While several reviews have highlighted the use of nanoparticles in sepsis, comprehensive studies that summarize and analyze the hotspots and research trends are lacking. To identify and further promote the development of nanotechnology in sepsis, a bibliometric analysis was conducted on the relevant literature, assessing research trends and hotspots in the application of nanomaterials for sepsis. Next, a comprehensive review of the subjectively recognized research hotspots in sepsis, including nanotechnology-enhanced biosensors and nanoscale imaging for sepsis diagnostics, and nanoplatforms designed for antimicrobial, immunomodulatory, and detoxification strategies in sepsis therapy, is elucidated, while the potential side effects and toxicity risks of these nanomaterials were discussed. Particular attention is given to biomimetic nanoparticles, which mimic the biological functions of source cells like erythrocytes, immune cells, and platelets to evade immune responses and effectively deliver therapeutic agents, demonstrating substantial translational potential. Finally, current challenges and future perspectives of nanotechnology applications in sepsis with a view to maximizing their great potential in the research of translational medicine are also discussed.

Exosomes derived from human umbilical cord mesenchymal stem cells decrease neuroinflammation and facilitate the restoration of nerve function in rats suffering from intracerebral hemorrhage

Exosomes derived from human umbilical cord mesenchymal stem cells (hUCMSC-ex) have become a hopeful substitute for whole-cell therapy due to their minimal immunogenicity and tumorigenicity. The present study aimed to investigate the hypothesis that hUCMSC-ex can alleviate excessive inflammation resulting from intracerebral hemorrhage (ICH) and facilitate the rehabilitation of the nervous system in rats. In vivo, hemorrhagic stroke was induced by injecting collagenase IV into the striatum of rats using stereotactic techniques. hUCMSC-ex were injected via the tail vein at 6 h after ICH model establishment at a dosage of 200 µg. In vitro, astrocytes were pretreated with hUCMSC-ex and then stimulated with hemin (20 μmol/mL) to establish an ICH cell model. The expression of TLR4/NF-κB signaling pathway proteins and inflammatory factors, including TNF-α, IL-1β, and IL-10, was assessed both in vivo and in vitro to investigate the impact of hUCMSC-ex on inflammation. The neurological function of the ICH rats was evaluated using the corner turn test, forelimb placement test, Longa score, and Bederson score on the 1st, 3rd, and 5th day. Additionally, RT-PCR was employed to examine the mRNA expression of TLR4 following hUCMSC-ex treatment. The findings demonstrated that hUCMSC-ex downregulated the protein expression of TLR4, NF-κB/P65, and p-P65, reduced the levels of pro-inflammatory cytokines TNF-α and IL-1β, and increased the expression of the anti-inflammatory cytokine IL-10. Ultimately, the administration of hUCMSC-ex improved the behavioral performance of the ICH rats. However, the results of PT-PCR indicated that hUCMSC-ex did not affect the expression of TLR4 mRNA induced by ICH, suggesting that hUCMSCs-ex may inhibit TLR4 translation rather than transcription, thereby suppressing the TLR4/NF-κB signaling pathway. We can conclude that hUCMSC-ex mitigates hyperinflammation following ICH by inhibiting the TLR4/NF-κB signaling pathway. This study provides preclinical evidence for the potential future application of hUCMSC-ex in the treatment of cerebral injury.

Mesenchymal stromal cells in myeloid malignancies: Immunotherapeutic opportunities

Myeloid malignancies are clonal disorders of the progenitor cells or hematopoietic stem cells, including acute myeloid leukemia, myelodysplastic syndromes, myeloproliferative malignancies, and chronic myelomonocytic leukemia. Myeloid neoplastic cells affect the proliferation and differentiation of other hematopoietic lineages in the bone marrow and peripheral blood, leading to severe and life-threatening complications. Mesenchymal stromal cells (MSCs) residing in the bone marrow exert immunosuppressive functions by suppressing innate and adaptive immune systems, thus creating a supportive and tolerant microenvironment for myeloid malignancy progression. This review summarizes the significant features of MSCs in myeloid malignancies, including their role in regulating cell growth, cell death, and antineoplastic resistance, in addition to their immunosuppressive contributions. Understanding the implications of MSCs in myeloid malignancies could pave the path for potential use in immunotherapy.

Comparison of the ability of exosomes and ectosomes derived from adipose-derived stromal cells to promote cartilage regeneration in a rat osteochondral defect model

BACKGROUND

Extracellular vesicles (EVs) derived from mesenchymal stromal cells (MSCs) offer promising prospects for stimulating cartilage regeneration. The different formation mechanisms suggest that exosomes and ectosomes possess different biological functions. However, little attention has been paid to the differential effects of EV subsets on cartilage regeneration.

METHODS

Our study compared the effects of the two EVs isolated from adipose-derived MSCs (ASCs) on chondrocytes and bone marrow-derived MSCs (BMSCs) in vitro. Additionally, we loaded the two EVs into type I collagen hydrogels to optimize their application for the treatment of osteochondral defects in vivo.

RESULTS

In vitro experiments demonstrate that ASC-derived exosomes (ASC-Exos) significantly promoted the proliferation and migration of both cells more effectively than ASC-derived ectosomes (ASC-Ectos). Furthermore, ASC-Exos facilitated a stronger differentiation of BMSCs into chondrogenic cells than ASC-Ectos, but both inhibited chondrocyte apoptosis to a similar extent. In the osteochondral defect model of rats, ASC-Exos promoted cartilage regeneration in situ better than ASC-Ectos. At 8 weeks, the hydrogel containing exosomes group (Gel + Exo group) had higher macroscopic and histological scores, a higher value of trabecular bone volume fraction (BV/TV), a lower value of trabecular thickness (Tb.Sp), and a better remodeling of extracellular matrix than the hydrogel containing ectosomes group (Gel + Ecto group). At 4 and 8 weeks, the expression of CD206 and Arginase-1 in the Gel + Exo group was significantly higher than that in the Gel + Ecto group.

CONCLUSION

Our findings indicate that administering ASC-Exos may be a more effective EV strategy for cartilage regeneration than the administration of ASC-Ectos.

Advancements in innate immune regulation strategies in islet transplantation

As a newly emerging organ transplantation technique, islet transplantation has shown the advantages of minimal trauma and high safety since it was first carried out. The proposal of the Edmonton protocol, which has been widely applied, was a breakthrough in this method. However, direct contact between islets and portal vein blood will cause a robust innate immune response leading to massive apoptosis of the graft, and macrophages play an essential role in the innate immune response. Therefore, therapeutic strategies targeting macrophages in the innate immune response have become a popular research topic in recent years. This paper will summarize and analyze recent research on strategies for regulating innate immunity, primarily focusing on macrophages, in the field of islet transplantation, including drug therapy, optimization of islet preparation process, islet engineering and Mesenchymal stem cells cotransplantation. We also expounded the heterogeneity, plasticity and activation mechanism of macrophages in islet transplantation, providing a theoretical basis for further research.

Dental-derived stem cells in tissue engineering: the role of biomaterials and host response

Dental-derived stem cells (DSCs) are attractive cell sources due to their easy access, superior growth capacity and low immunogenicity. They can respond to multiple extracellular matrix signals, which provide biophysical and biochemical cues to regulate the fate of residing cells. However, the direct transplantation of DSCs suffers from poor proliferation and differentiation toward functional cells and low survival rates due to local inflammation. Recently, elegant advances in the design of novel biomaterials have been made to give promise to the use of biomimetic biomaterials to regulate various cell behaviors, including proliferation, differentiation and migration. Biomaterials could be tailored with multiple functionalities, e.g., stimuli-responsiveness. There is an emerging need to summarize recent advances in engineered biomaterials-mediated delivery and therapy of DSCs and their potential applications. Herein, we outlined the design of biomaterials for supporting DSCs and the host response to the transplantation.

ERK1-mediated immunomodulation of mesenchymal stem cells ameliorates inflammatory disorders

Immune system disorders, especially T cell disorders, are important therapeutic targets of mesenchymal stem cells (MSCs) in many autoimmune diseases (ADs). Although extracellular regulated protein kinases (ERKs) play a role in MSC therapy by promoting T cell apoptosis, the mechanism remains unclear. Our findings indicate that ERK1-/- bone marrow MSCs (BMMSCs), but not ERK2-/- BMMSCs, failed to promote T cell apoptosis due to incapacity to activate the ETS2/AURKA/NF-κB/Fas/MCP-1 cascade. Moreover, ERK1-/- BMMSCs were unable to upregulate regulatory T cells and suppress T helper 17 cells. Licochalcone A (LA), which promotes ERK pathway activation, enhanced the therapeutic efficacy of MSC therapy in ulcerative colitis and collagen-induced arthritis mice. Our findings suggest that ERK1, but not ERK2, plays a crucial role in regulating T cells in MSCs. LA-treated MSCs provide a strategy to improve the efficacy of MSC-based treatments for ADs.

Multiple Injections of Adipose-Derived Stem Cells Improve Graft Survival in Human-to-Rat Skin Xenotransplantation through Immune Modulation

BACKGROUND

Adipose-derived stem cells (ADSCs) exert immunomodulatory effects in the treatment of transplant rejection. This study aimed to evaluate the effects of ADSCs on the skin graft survival in a human-to-rat xenograft transplantation model and to compare single and multiple injections of ADSCs.

METHODS

Full-thickness human skin xenografts were transplanted into the backs of Sprague-Dawley rats. The rats were injected subcutaneously on postoperative days 0, 3, and 5. The injections were as follows: triple injections of phosphate-buffered saline (PBS group), a single injection of ADSCs and double injections of PBS (ADSC × 1 group), and triple injections of ADSCs (ADSC × 3 group). The immunomodulatory effects of ADSCs on human skin xenografts were assessed.

RESULTS

Triple injections of ADSCs considerably delayed cell-mediated xenograft rejection compared with the PBS and ADSC × 1 groups. The vascularization and collagen type 1-3 ratios in the ADSC × 3 group were significantly higher than those in the other groups. In addition, intragraft infiltration of CD3-, CD4-, CD8-, and CD68-positive cells was reduced in the ADSC × 3 group. Furthermore, in the ADSC × 3 group, the expression levels of proinflammatory cytokine interferon-gamma (IFN-γ) were decreased and immunosuppressive prostaglandin E synthase (PGES) was increased in the xenograft and lymph node samples.

CONCLUSION

This study presented that triple injections of ADSCs appeared to be superior to a single injection in suppressing cell-mediated xenograft rejection. The immunomodulatory effects of ADSCs are associated with the downregulation of IFN-γ and upregulation of PGES in skin xenografts and lymph nodes.

The developing role of extracellular vesicles in autoimmune diseases: special attention to mesenchymal stem cell-derived extracellular vesicles

Autoimmune diseases are complex, chronic inflammatory conditions initiated by the loss of immunological tolerance to self-antigens. Nowadays, there is no effective and useful therapy for autoimmune diseases, and the existing medications have some limitations due to their nonspecific targets and side effects. During the last few decades, it has been established that mesenchymal stem cells (MSCs) have immunomodulatory functions. It is proposed that MSCs can exert an important therapeutic effect on autoimmune disorders. In parallel with these findings, several investigations have shown that MSCs alleviate autoimmune diseases. Intriguingly, the results of studies have demonstrated that the effective roles of MSCs in autoimmune diseases do not depend on direct intercellular communication but on their ability to release a wide spectrum of paracrine mediators such as growth factors, cytokines and extracellular vehicles (EVs). EVs that range from 50 to 5,000 nm were produced by almost any cell type, and these nanoparticles participate in homeostasis and intercellular communication via the transfer of a broad range of biomolecules such as modulatory proteins, nucleic acids (DNA and RNA), lipids, cytokines, and metabolites. EVs derived from MSCs display the exact properties of MSCs and can be safer and more beneficial than their parent cells. In this review, we will discuss the features of MSCs and their EVs, EVs biogenesis, and their cargos, and then we will highlight the existing discoveries on the impacts of EVs from MSCs on autoimmune diseases such as multiple sclerosis, arthritis rheumatic, inflammatory bowel disease, Type 1 diabetes mellitus, systemic lupus erythematosus, autoimmune liver diseases, Sjögren syndrome, and osteoarthritis, suggesting a potential alternative for autoimmune conditions therapy.

Efficacy of Wharton Jelly Mesenchymal Stromal Cells infusions in moderate to severe SARS-Cov-2 related acute respiratory distress syndrome: a phase 2a double-blind randomized controlled trial

Background

The COVID-19 pandemic caused a wave of acute respiratory distress syndrome (ARDS) with a high in-hospital mortality, especially in patients requiring invasive mechanical ventilation. Wharton Jelly-derived Mesenchymal Stromal Cells (WJ-MSCs) may counteract the pulmonary damage induced by the SARS-CoV-2 infection through pro-angiogenic effects, lung epithelial cell protection, and immunomodulation.

Methods

In this randomized, double-blind, placebo-controlled phase 2a trial, adult patients receiving invasive mechanical ventilation for SARS-CoV-2 induced moderate or severe ARDS were assigned to receive 1 intravenous infusion of 1 × 106 WJ-MSCs/kg or placebo within 48 h of invasive ventilation followed by 2 infusions of 0.5 × 106 WJ-MSCs/kg or placebo over 5 days. The primary endpoint was the percentage of patients with a PaO2/FiO2 > 200 on day 10.

Results

Thirty patients were included from November 2020 to May 2021, 15 in the WJ-MSC group and 15 in the placebo group. We did not find any significant difference in the PaO2/FiO2 ratio at day 10, with 18 and 15% of WJ-MSCs and placebo-treated patients reaching a ratio >200, respectively. Survival did not differ in the 2 groups with a 20% mortality rate at day 90. While we observed a higher number of ventilation-free days at 28 days in the WJ-MSC arm, this difference was not statistically significant (median of 11 (0-22) vs. 0 (0-18), p = 0.2). The infusions were well tolerated, with a low incidence of anti-HLA alloimmunization after 90 days.

Conclusion

While treatment with WJ-MSCs appeared safe and feasible in patients with SARS-CoV2 moderate or severe ARDS in this phase 2a trial, the treatment was not associated with an increased percentage of patients with P/F > 200 at 10d, nor did 90 day mortality improve in the treated group.

Clinical trial registration

https://beta.clinicaltrials.gov/study/NCT04625738, identifier NCT04625738.

Single-Cell Sequencing Informs That Mesenchymal Stem Cell Alleviates Renal Injury Through Regulating Kidney Regional Immunity in Lupus Nephritis

Lupus nephritis (LN) is the common complication of systemic lupus erythematosus. The pathogenesis of LN kidney injury is unclear. In addition to systemic (extrarenal) immune cells, local (intrarenal) immune cells residing in "kidney regional immunity" are momentous in LN. Mesenchymal stem cell (MSC) therapy is effective for LN. However, mechanisms of MSC therapy remains unclear. In this study, we first systematically investigated the effects of MSC on immune cells in kidney regional immunity in LN using single-cell sequencing. We found that MSC reduced proinflammatory central memory CD4+ T cells, cytotoxic tissue-resident memory CD8+ T cells and exhausted CD8+ T cells, increased anti-inflammatory Naive/Effector CD8+ T cells and type 1 regulatory T cells; reduced infiltrating proinflammatory Ly6c hi/inter/lo era2+ macrophages, increased anti-inflammatory resident macrophage and Ly6c lo ear2- macrophage; and reduced long-lived plasma cells and proinflammatory neutrophils and dendritic cells. This study laid a foundation for clinical applications of MSC.

Biogenesis, Composition and Potential Therapeutic Applications of Mesenchymal Stem Cells Derived Exosomes in Various Diseases

Exosomes are nanovesicles with a wide range of chemical compositions used in many different applications. Mesenchymal stem cell-derived exosomes (MSCs-EXOs) are spherical vesicles that have been shown to mediate tissue regeneration in a variety of diseases, including neurological, autoimmune and inflammatory, cancer, ischemic heart disease, lung injury, and liver fibrosis. They can modulate the immune response by interacting with immune effector cells due to the presence of anti-inflammatory compounds and are involved in intercellular communication through various types of cargo. MSCs-EXOs exhibit cytokine storm-mitigating properties in response to COVID-19. This review discussed the potential function of MSCs-EXOs in a variety of diseases including neurological, notably epileptic encephalopathy and Parkinson's disease, cancer, angiogenesis, autoimmune and inflammatory diseases. We provided an overview of exosome biogenesis and factors that regulate exosome biogenesis. Additionally, we highlight the functions and potential use of MSCs-EXOs in the treatment of the inflammatory disease COVID-19. Finally, we covered a strategies and challenges of MSCs-EXOs. Finally, we discuss conclusion and future perspectives of MSCs-EXOs.

Bioengineered stem cell membrane functionalized nanoparticles combine anti-inflammatory and antimicrobial properties for sepsis treatment

BACKGROUND

Sepsis is a syndrome of physiological, pathological and biochemical abnormalities caused by infection. Although the mortality rate is lower than before, many survivors have persistent infection, which means sepsis calls for new treatment. After infection, inflammatory mediators were largely released into the blood, leading to multiple organ dysfunction. Therefore, anti-infection and anti-inflammation are critical issues in sepsis management.

RESULTS

Here, we successfully constructed a novel nanometer drug loading system for sepsis management, FZ/MER-AgMOF@Bm. The nanoparticles were modified with LPS-treated bone marrow mesenchymal stem cell (BMSC) membrane, and silver metal organic framework (AgMOF) was used as the nanocore for loading FPS-ZM1 and meropenem which was delivery to the infectious microenvironments (IMEs) to exert dual anti-inflammatory and antibacterial effects. FZ/MER-AgMOF@Bm effectively alleviated excessive inflammatory response and eliminated bacteria. FZ/MER-AgMOF@Bm also played an anti-inflammatory role by promoting the polarization of macrophages to M2. When sepsis induced by cecal ligation and puncture (CLP) challenged mice was treated, FZ/MER-AgMOF@Bm could not only reduce the levels of pro-inflammatory factors and lung injury, but also help to improve hypothermia caused by septic shock and prolong survival time.

CONCLUSIONS

Together, the nanoparticles played a role in combined anti-inflammatory and antimicrobial properties, alleviating cytokine storm and protecting vital organ functions, could be a potential new strategy for sepsis management.

Efficacy and safety of human umbilical cord-derived mesenchymal stem cells (hUC-MSC PLEB001) for the treatment of grade II-IV steroid-refractory acute graft-versus-host disease: a study protocol for a multicenter, randomized, double-blind, placebo-controlled, phase II trial

BACKGROUND

Systemic corticosteroid therapy failure is quite common in patients with newly diagnosed acute graft-versus-host disease (aGVHD). Growing evidence has suggested that mesenchymal stem cell (MSC) therapy could be a promising treatment option for aGVHD due to its distinctive immunomodulating functions. However, there is a lack of randomized well-controlled clinical trials.

METHODS

This is a clinical trial protocol for a multicenter, randomized, double-blind, placebo-controlled phase II study. The aim of the trial is to evaluate the efficacy and safety of the administration of the human umbilical cord-derived MSC product hUC-MSC PLEB001 in patients with grade II-IV, steroid-refractory aGVHD. A total of 96 patients will be randomized 1:1 to receive MSC or placebo treatment twice per week for 4 weeks, in addition to second-line therapy according to institutional standards. Patients who achieve partial response (PR) at day 28 will be eligible to receive further infusions twice per week for an additional 4 weeks.

DISCUSSION

This study will evaluate the efficacy and safety of MSC therapy in patients who have failed first-line steroid treatment for grade II-IV aGVHD.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR), ChiCTR2000035740. Registered on 16 August 2020.

A hybrid cartilage extracellular matrix-based hydrogel/poly (ε-caprolactone) scaffold incorporated with Kartogenin for cartilage tissue engineering

Despite extensive studies, hydrogels are unable to meet the mechanical and biological requirements for successful outcomes in cartilage tissue engineering. In the present study, beta cyclodextrin (β-CD)-modified alginate/cartilage extracellular matrix (ECM)-based interpenetrating polymer network (IPN) hydrogel was developed for sustained release of Kartogenin (KGN). Furthermore, the hydrogel was incorporated within a 3D-printed poly (ε-caprolactone) (PCL)/starch microfiber network in order to reinforce the construct for cartilage tissue engineering. All the synthesized compounds were characterized by H¹-NMR spectroscopy. The hydrogel/microfiber composite with a microfiber strand size and strand spacing of 300 μm and 2 mm, respectively showed a compressive modulus of 17.2 MPa, resembling the properties of the native cartilage tissue. Considering water uptake capacity, degradation rate, mechanical property, cell cytotoxicity and glycosaminoglycan secretions, β-CD-modified hydrogel reinforced with printed PCL/starch microfibers with controlled release of KGN may be considered as a promising candidate for using in articular cartilage defects.

Delphinidin-3-O-glucoside in vitro suppresses NF-κB and changes the secretome of mesenchymal stem cells affecting macrophage activation

OBJECTIVE

Anthocyanins are polyphenols that are promising chemopreventive agents. They stand out for their anti-inflammatory properties, with specific modulatory actions on the immune system. Additionally, regarding the immune system, a group of cells identified as mesenchymal stem cells (MSCs) have been attracting attention, mainly because of their capacity to migrate to sites of inflammation and produce potent immunomodulatory effects. Considering the ability of these cells to act on the immune system, as well as the properties of anthocyanins, especially delphinidin, in modulating the immune system, the aim of this study was to investigate the effects of delphinidin in influencing some immunoregulatory properties of MSCs.

METHODS

MSCs were cultivated in the presence of delphinidin 3-O-β-d-glycoside and cell viability, the cell cycle and the production of soluble factors (interleukin [IL]-1β, IL-6, IL-10, transforming growth factor [TGF]-β, prostaglandin E₂ [PGE₂] and nitric oxide [NO]) were evaluated, as was the expression of the transcription factors nuclear factor (NF)-κB and STAT3. Additionally, the effects of conditioned media from MSCs on macrophage activation were assessed.

RESULTS

Delphinidin at 50 µM does not affect cell viability. In association with lipopolysaccharide, delphinidin was able to induce MSC proliferation. Additionally, delphinidin modulated the MSC immune response, showing increased levels of anti-inflammatory cytokines such as IL-10 and TGF-β as well as lower expression of NF-κB. Furthermore, conditioned media from MSCs inhibited macrophage metabolism, reducing the production of IL-1β, IL-12, and TNF-α and increasing IL-10.

CONCLUSIONS

Overall, this work showed that delphinidin can modify the immunomodulatory properties of MSCs, increasing the IL-10 production by macrophages.

Ex Vivo Treatment with Allogenic Mesenchymal Stem Cells of a Healthy Donor on Peripheral Blood Mononuclear Cells of Patients with Severe Alopecia Areata: Targeting Dysregulated T Cells and the Acquisition of Immunotolerance

Alopecia areata (AA) is an autoimmune condition related to the collapse of the immune privilege of hair follicles. Certain AA populations present severe clinical manifestations, such as total scalp hair or body hair loss and a treatment refractory property. The aim of this study was to assess the effects of allogenic human mesenchymal stem cells (hMSCs) from healthy donors on the peripheral blood mononuclear cells (PBMCs) of severe AA patients, with a focus on the change in the cell fraction of Th1, Th17, and Treg cells and immunomodulatory functions. PBMCs of 10 AA patients and eight healthy controls were collected. Levels of Th17, Th1, and Treg subsets were determined via flow cytometry at baseline, activation status, and after co-culturing with hMSCs. All participants were severe AA patients with SALT > 50 and with a long disease duration. While the baseline Th1 and Treg levels of AA patients were comparable to those of healthy controls, their Th17 levels were significantly lower than those of the controls. When stimulated, the levels of CD4+IFN-γ+ T cells of the AA patients rose sharply compared to the baseline, which was not the case in those of healthy controls. The cell fraction of CD4+Foxp3+ regulatory T cells also abruptly increased in AA patients only. Co-culturing with allogenic hMSCs in activated AA PBMCs slightly suppressed the activation levels of CD4+INF-γ+ T cells, whereas it significantly induced the differentiation of CD4+Foxp3+ regulatory T cells. However, these changes were not prominent in the PBMCs of health controls. To examine the pathomechanisms, PBMCs of healthy donors were treated with IFN-γ to induce AA-like environment and then treated with allogenic grants and compared with ruxolitinib as a positive treatment control. hMSC treatment was shown to significantly inhibit the mRNA levels of proinflammatory cytokines, such as IFN-γ, TNF-α, IL-1α, IL-2R, IL-15, and IL-18, and chemokines, such as CCR7 and CCR10, in IFN-treated PBMCs. Interestingly, hMSCs suppressed the activation of JAK/STAT signaling by IFN in PBMCs with an effect that was comparable to that of ruxolitinib. Furthermore, the hMSC treatment showed stronger efficacy in inducing Foxp3, IL-10, and TGF-β mRNA transcription than ruxolitinib in IFN-treated PBMCs. This study suggests that allogenic hMSC treatments have therapeutic potential to induce immune tolerance and anti-inflammatory effects in severe AA patients.

Mesenchymal stroma/stem cells: Haematologists' friend or foe?

Mesenchymal stromal cells (MSCs) are non-haematopoietic cells found in fetal and adult organs, that play important roles in tissue repair, inflammation and immune modulation. MSCs residing in the bone marrow interact closely with haematopoietic cells and comprise an important component of the microenvironment supporting haematopoiesis, in both health and disease states. Since their identification in 1970, basic scientific and preclinical research efforts have shed light on the role of MSCs in the regulation of haematopoiesis and evoked interest in their clinical application in haematopoietic stem cell transplantation (HSCT) and malignant haematology. Over the last two decades, these research efforts have led to numerous clinical trials, which have established the safety of MSC therapy; however, the optimal mode of administration and the benefit remain inconclusive. In this paper, we will review the clinical experience with use of MSCs in HSCT for enhancement of engraftment, prevention and treatment of graft-versus-host disease and haemorrhagic cystitis. Then, we will discuss the contradictory evidence regarding tumour-promoting versus tumour-suppressing effects of MSCs in haematological malignancies, which may have relevance for future clinical applications.

The dark side of adipose-derived mesenchymal stromal cells in cutaneous oncology: roles, expectations, and potential pitfalls

Adipose-derived stromal cells (ADSCs) have well-established regenerative and immunomodulatory properties. For such reasons, ADSCs are currently under investigation for their use in the setting of both regenerative medicine and autoimmune diseases. As per dermatological disorders, MSC-based strategies represent potential therapeutic tools not only for chronic ulcers and wound healing, but also for immune-mediated dermatoses. However, a growing body of research has been focusing on the role of MSCs in human cancers, due to the potential oncological risk of using MSC-based strategies linked to their anti-apoptotic, pro-angiogenic and immunosuppressive properties. In the dermatological setting, ADSCs have shown not only to promote melanoma growth and invasiveness, but also to induce drug-resistance. On the other hand, genetically modified ADSCs have been demonstrated to efficiently target therapies at tumor sites, due to their migratory properties and their peculiar tropism for cancer microenvironment. The present review briefly summarizes the findings published so far on the use of ADSCs in the dermato-oncological setting, with the majority of data being available for melanoma.

Engineering of hybrid spheroids of mesenchymal stem cells and drug depots for immunomodulating effect in islet xenotransplantation

Immunomodulation is an essential consideration for cell replacement procedures. Unfortunately, lifelong exposure to nonspecific systemic immunosuppression results in immunodeficiency and has toxic effects on nonimmune cells. Here, we engineered hybrid spheroids of mesenchymal stem cells (MSCs) with rapamycin-releasing poly(lactic-co-glycolic acid) microparticles (RAP-MPs) to prevent immune rejection of islet xenografts in diabetic C57BL/6 mice. Hybrid spheroids were rapidly formed by incubating cell-particle mixture in methylcellulose solution while maintaining high cell viability. RAP-MPs were uniformly distributed in hybrid spheroids and sustainably released RAP for ~3 weeks. Locoregional transplantation of hybrid spheroids containing low doses of RAP-MPs (200- to 4000-ng RAP per recipient) significantly prolonged islet survival times and promoted the generation of regional regulatory T cells. Enhanced programmed death-ligand 1 expression by MSCs was found to be responsible for the immunomodulatory performance of hybrid spheroids. Our results suggest that these hybrid spheroids offer a promising platform for the efficient use of MSCs in the transplantation field.

Comparing the immunomodulatory properties of equine BM-MSCs culture expanded in autologous platelet lysate, pooled platelet lysate, equine serum and fetal bovine serum supplemented culture media

Joint injury often leads to cartilage damage and posttraumatic inflammation, which drives continued extracellular matrix degradation culminating in osteoarthritis. Mesenchymal stem cells (MSCs) have been proposed as a biotherapeutic to modulate inflammation within the joint. However, concerns have been raised regarding the immunogenicity of MSCs cultured in traditional fetal bovine serum (FBS) containing media, and the potential of xenogenic antigens to activate the immune system causing rejection and destruction of the MSCs. Xenogen-free alternatives to FBS have been proposed to decrease MSC immunogenicity, including platelet lysate (PL) and equine serum. The objective of this study was to compare the immunomodulatory properties of BM-MSCs culture-expanded in media supplemented with autologous PL (APL), pooled PL (PPL), equine serum (ES) or FBS. We hypothesized that BM-MSCs culture expanded in media with xenogen-free supplements would exhibit superior immunomodulatory properties to those cultured in FBS containing media. Bone marrow-derived MSCs (BM-MSCs) were isolated from six horses and culture expanded in each media type. Blood was collected from each horse to isolate platelet lysate. The immunomodulatory function of the BM-MSCs was assessed via a T cell proliferation assay and through multiplex immunoassay quantification of cytokines, including IL-1β, IL-6, IL-8, IL-10, and TNFα, following preconditioning of BM-MSCs with IL-1β. The concentration of platelet-derived growth factor BB (PDGF-BB), IL-10, and transforming growth factor-β (TGF-β) in each media was measured via immunoassay. BM-MSCs cultured in ES resulted in significant suppression of T cell proliferation (p = 0.02). Cell culture supernatant from preconditioned BM-MSCs cultured in ES had significantly higher levels of IL-6. PDGF-BB was significantly higher in APL media compared to FBS media (p = 0.016), while IL-10 was significantly higher in PPL media than ES and FBS (p = 0.04). TGF-β was highest in APL media, with a significant difference in comparison to ES media (p = 0.03). In conclusion, expansion of equine BM-MSCs in ES may enhance their immunomodulatory abilities, while PL containing media may have some inherent therapeutic potential associated with higher concentrations of growth factors. Further studies are needed to elucidate which xenogen-free supplement optimizes BM-MSC performance.

Muse cells: ushering in a new era of stem cell-based therapy for stroke

Stem cell-based regenerative therapies have recently become promising and advanced for treating stroke. Mesenchymal stem cells (MSCs) and induced pluripotent stem cells (iPSCs) have received the most attention for treating stroke because of the outstanding paracrine function of MSCs and the three-germ-layer differentiation ability of iPSCs. However, the unsatisfactory homing ability, differentiation, integration, and survival time in vivo limit the effectiveness of MSCs in regenerative medicine. The inherent tumorigenic property of iPSCs renders complete differentiation necessary before transplantation, which is complicated and expensive and affects the consistency among cell batches. Multilineage differentiating stress-enduring (Muse) cells are natural pluripotent stem cells in the connective tissues of nearly every organ and thus are considered nontumorigenic. A single Muse cell can differentiate into all three-germ-layer, preferentially migrate to damaged sites after transplantation, survive in hostile environments, and spontaneously differentiate into tissue-compatible cells, all of which can compensate for the shortcomings of MSCs and iPSCs. This review summarizes the recent progress in understanding the biological properties of Muse cells and highlights the differences between Muse cells and other types of stem cells. Finally, we summarized the current research progress on the application of Muse cells on stroke and challenges from bench to bedside.

Mesenchymal stem/stromal cells in the pathogenesis and regenerative therapy of inflammatory bowel diseases

Inflammatory bowel diseases (IBDs) represent a group of chronic inflammatory disorders of the gastrointestinal (GI) tract including ulcerative colitis (UC), Crohn’s disease (CD), and unclassified IBDs. The pathogenesis of IBDs is related to genetic susceptibility, environmental factors, and dysbiosis that can lead to the dysfunction of immune responses and dysregulated homeostasis of local mucosal tissues characterized by severe inflammatory responses and tissue damage in GI tract. To date, extensive studies have indicated that IBDs cannot be completely cured and easy to relapse, thus prompting researchers to find novel and more effective therapeutics for this disease. Due to their potent multipotent differentiation and immunomodulatory capabilities, mesenchymal stem/stromal cells (MSCs) not only play an important role in regulating immune and tissue homeostasis but also display potent therapeutic effects on various inflammatory diseases, including IBDs, in both preclinical and clinical studies. In this review, we present a comprehensive overview on the pathological mechanisms, the currently available therapeutics, particularly, the potential application of MSCs-based regenerative therapy for IBDs.

Mesenchymal stem cell-derived extracellular vesicles for immunomodulation and regeneration: a next generation therapeutic tool?

Mesenchymal stem cells (MSCs) can be widely isolated from various tissues including bone marrow, umbilical cord, and adipose tissue, with the potential for self-renewal and multipotent differentiation. There is compelling evidence that the therapeutic effect of MSCs mainly depends on their paracrine action. Extracellular vesicles (EVs) are fundamental paracrine effectors of MSCs and play a crucial role in intercellular communication, existing in various body fluids and cell supernatants. Since MSC-derived EVs retain the function of protocells and have lower immunogenicity, they have a wide range of prospective therapeutic applications with advantages over cell therapy. We describe some characteristics of MSC-EVs, and discuss their role in immune regulation and regeneration, with emphasis on the molecular mechanism and application of MSC-EVs in the treatment of fibrosis and support tissue repair. We also highlight current challenges in the clinical application of MSC-EVs and potential ways to overcome the problem of quality heterogeneity.

The Effect of Mesenchymal Stromal Cells on the Mortality of Patients with Sepsis and Septic Shock: A Promising Therapy

Purpose

Sepsis and septic shock are the major causes of death in intensive care units. This study aimed to evaluate the clinical safety and efficacy of mesenchymal stem cells (MSCs) in sepsis and septic shock patients.

Methods

Ten patients were enrolled in the study. Adipose-derived MSC infusions were given (1 × 10⁶/kg, on the 1^st, 3^rd, 5^th, 7^th, and 9^th days of therapy) together with standard therapy. Before the MSC applications, blood samples were collected for cytokine assessment (TNF-α, IFN-γ, IL-2, IL-4, IL-6, IL-10). The clinical and laboratory improvements were recorded and compared with control groups selected retrospectively. The clinical trial was registered on 16.03.2022 with the registration number NCT05283317.

Results

In the study group, the ages of patients ranged from 22 to 68 years, and APACHE II scores ranged from 14 to 42. In the control group, ages ranged from 22 to 80 years and their APACHE II scores were between 14–35. The survival rate in the study group was 100% on the 14^th day whereas it was 70% on the 28^th day. A significant decrease in the SOFA score (adjusted), clinical, and laboratory improvements were observed during the MSC administration. However, no significant cytokine level changes were observed. In the control group, the survival rate of 20 patients was 70% on the 14^th day, whereas 60% was on the 28^th day. While deaths were observed in the control group in the first week of treatment, deaths in the MSCs group were observed between the 15^th and 28^th days.

Conclusion

MSCs treatment may have a positive impact on the survival rates of sepsis during the early phase. However, further randomized controlled studies with a large group of patients are needed. Trial Registration. This trial is registered with ClinicalTrials.gov Identifier: NCT05283317.

The Effect of Mesenchymal Stromal Cells on the Mortality of Patients with Sepsis and Septic Shock: A Promising Therapy

Purpose. Sepsis and septic shock are the major causes of death in intensive care units. This study aimed to evaluate the clinical safety and efficacy of mesenchymal stem cells (MSCs) in sepsis and septic shock patients. Methods. Ten patients were enrolled in the study. Adipose-derived MSC infusions were given (1 × 106/kg, on the 1st, 3rd, 5th, 7th, and 9th days of therapy) together with standard therapy. Before the MSC applications, blood samples were collected for cytokine assessment (TNF-α, IFN-γ, IL-2, IL-4, IL-6, IL-10). The clinical and laboratory improvements were recorded and compared with control groups selected retrospectively. The clinical trial was registered on 16.03.2022 with the registration number NCT05283317. Results. In the study group, the ages of patients ranged from 22 to 68 years, and APACHE II scores ranged from 14 to 42. In the control group, ages ranged from 22 to 80 years and their APACHE II scores were between 14–35. The survival rate in the study group was 100% on the 14th day whereas it was 70% on the 28th day. A significant decrease in the SOFA score (adjusted), clinical, and laboratory improvements were observed during the MSC administration. However, no significant cytokine level changes were observed. In the control group, the survival rate of 20 patients was 70% on the 14th day, whereas 60% was on the 28th day. While deaths were observed in the control group in the first week of treatment, deaths in the MSCs group were observed between the 15th and 28th days. Conclusion. MSCs treatment may have a positive impact on the survival rates of sepsis during the early phase. However, further randomized controlled studies with a large group of patients are needed. Trial Registration. This trial is registered with ClinicalTrials.gov Identifier: NCT05283317.

Interferon-γ enhances the immunosuppressive ability of canine bone marrow-derived mesenchymal stem cells by activating the TLR3-dependent IDO/kynurenine pathway

BACKGROUND

The immunomodulatory function of mesenchymal stem cells (MSCs) has been considered to be vital for MSC-based therapies. Many works have been devoted to excavate effective strategies for enhancing the immunomodulation effect of MSCs. Nonetheless, canine MSC-mediated immunomodulation is still poorly understood.

METHODS AND RESULTS

The inflammatory microenvironment was simulated through the employment of interferon-γ (IFN-γ) in a culture system. Compared with unstimulated cBMSCs, IFN-γ stimulation increased the mRNA levels of Toll-like receptor 3 (TLR3) and indoleamine 2, 3-dioxygenase 1 (IDO-1), and simultaneously enhanced the secretion of immunosuppressive molecules, including interleukin (IL)-10, hepatocyte growth factor (HGF), and kynurenine in cBMSCs. IFN-γ stimulation significantly enhanced the ability of cBMSCs and their supernatant to suppress the proliferation of murine spleen lymphocytes. Lymphocyte subtyping evaluation revealed that cBMSCs and their supernatant diminished the percentage of CD3⁺CD4⁺ and CD3⁺CD8⁺ lymphocytes compared with the control group, with a decreasing CD4⁺/CD8⁺ ratio. Notably, exposure to IFN-γ decreased the CD4⁺/CD8⁺ ratio more effectively than unstimulated cells or supernatant. Additionally, IFN-γ-stimulation increased the mRNA levels of the Th1 cytokines TNF-α, and remarkably decreased the mRNA level of the Th2 cytokine IL-4 and IL-10.

CONCLUSION

Our findings substantiate that IFN-γ stimulation can enhance the immunomodulatory properties of cBMSCs by promoting TLR3-dependent activation of the IDO/kynurenine pathway, increasing the secretion of immunoregulatory molecules and strengthening interactions with T lymphocytes, which may provide a meaningful strategy for the clinical application of cBMSCs in immune-related diseases.

Long-term observation after transplantation of cultured human corneal endothelial cells for corneal endothelial dysfunction

Background

Corneal transplantation is the only way to treat serious corneal diseases caused by corneal endothelial dysfunction. However, the shortage of donor corneal tissues and human corneal endothelial cells (HCECs) remains a worldwide challenge. We cultivated HCECs by the use of a conditioned medium from orbital adipose-derived stem cells (OASC-CM) in vitro. Then the HCECs were used to treat animal corneal endothelial dysfunction models via cell transplantation. The purpose of this study was to conduct a long-term observation and evaluation after cell transplantation.

Methods

Orbital adipose-derived stem cells (OASCs) were isolated to prepare the conditioned medium (CM). HCECs were cultivated and expanded by the usage of the CM (CM-HCECs). Then, related corneal endothelial cell (CEC) markers were analyzed by immunofluorescence. The cell proliferation ability was also tested. CM-HCECs were then transplanted into monkey corneal endothelial dysfunction models by injection. We carried out a 24-month postoperative preclinical observation and verified the long-term effect by histological examination and transcriptome sequencing.

Results

CM-HCECs strongly expressed CEC-related markers and maintained polygonal cell morphology even after 10 passages. At 24 months after cell transplantation, there was a CEC density of more than 2400 cells per square millimeter (range, 2408–2685) in the experimental group. A corneal thickness (CT) of less than 550 μm (range, 490–510) was attained. Gene sequencing showed that the gene expression pattern of CM-HCECs was similar to that of transplanted cells and HCECs.

Conclusions

Transplantation of CM-HCECs into monkey corneal endothelial dysfunction models resulted in a transparent cornea after 24 months. This research provided a promising prospect of cell-based therapy for corneal endothelial diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02889-x.

Bone marrow mesenchymal stem cells alleviate the formation of pathological scars in rats

Introduction

Methods

Results

Conclusions

Target receptor identification and subsequent treatment of resected brain tumors with encapsulated and engineered allogeneic stem cells

Cellular therapies offer a promising therapeutic strategy for the highly malignant brain tumor, glioblastoma (GBM). However, their clinical translation is limited by the lack of effective target identification and stringent testing in pre-clinical models that replicate standard treatment in GBM patients. In this study, we show the detection of cell surface death receptor (DR) target on CD146-enriched circulating tumor cells (CTC) captured from the blood of mice bearing GBM and patients diagnosed with GBM. Next, we developed allogeneic "off-the-shelf" clinical-grade bifunctional mesenchymal stem cells (MSCBif) expressing DR-targeted ligand and a safety kill switch. We show that biodegradable hydrogel encapsulated MSCBif (EnMSCBif) has a profound therapeutic efficacy in mice bearing patient-derived invasive, primary and recurrent GBM tumors following surgical resection. Activation of the kill switch enhances the efficacy of MSCBif and results in their elimination post-tumor treatment which can be tracked by positron emission tomography (PET) imaging. This study establishes a foundation towards a clinical trial of EnMSCBif in primary and recurrent GBM patients.

Therapeutic role of mesenchymal stem cell-derived exosomes in respiratory disease

Exosomes are extracellular vesicles found in various tissues, blood circulation, and tissue fluids, secreted into the extracellular environment by fusing a multivesicular body with a plasma membrane. Various cell types release these vesicles to contribute to many cellular functions, including intercellular communication, cell proliferation, differentiation, angiogenesis, response to stress, and immune system signaling. These natural nanoparticles have therapeutic effects in various diseases and exhibit a behavior similar to the cell from which they originated. In the meantime, exosomes derived from mesenchymal stem cells have attracted the attention of many researchers and physicians due to their unique ability to modulate the immune system, repair tissue and reduce inflammation. Numerous clinical and preclinical studies have examined the effect of MSC-derived exosomes in various diseases, and their results have been published in prestigious journals. This review article discusses the biogenesis and sources of exosomes, MSC-derived exosomes, the use of these exosomes in regenerative medicine, and treatments based on exosomes derived from stem cells in respiratory diseases.

Exosomes Derived From Mesenchymal Stem Cells: Novel Effects in the Treatment of Ischemic Stroke

Ischemic stroke is defined as an infarction in the brain, caused by impaired cerebral blood supply, leading to local brain tissue ischemia, hypoxic necrosis, and corresponding neurological deficits. At present, revascularization strategies in patients with acute ischemic stroke include intravenous thrombolysis and mechanical endovascular treatment. However, due to the short treatment time window (<4.5 h) and method restrictions, clinical research is focused on new methods to treat ischemic stroke. Exosomes are nano-sized biovesicles produced in the endosomal compartment of most eukaryotic cells, containing DNA, complex RNA, and protein (30-150 nm). They are released into surrounding extracellular fluid upon fusion between multivesicular bodies and the plasma membrane. Exosomes have the characteristics of low immunogenicity, good innate stability, high transmission efficiency, and the ability to cross the blood-brain barrier, making them potential therapeutic modalities for the treatment of ischemic stroke. The seed sequence of miRNA secreted by exosomes is base-paired with complementary mRNA to improve the microenvironment of ischemic tissue, thereby regulating downstream signal transduction activities. With exosome research still in the theoretical and experimental stages, this review aims to shed light on the potential of exosomes derived from mesenchymal stem cells in the treatment of ischemic stroke.

Deciphering Stem Cell from Apical Papilla - Macrophage Choreography using a Novel 3D Organoid System

INTRODUCTION

Immune cell - mesenchymal stem cell crosstalk modulates the process of repair and regeneration. In this study, a novel heterogenous cell containing matrix based three-dimensional (3D) tissue-construct was employed to study the interactions between stem cells from apical papilla (SCAP) and macrophage for a comprehensive understanding on the cellular signalling mechanisms guiding inflammation and repair.

METHODS

SCAP and macrophages were seeded with collagen in 3D printed molds to generate self-assembled tissue-constructs, which were exposed to three conditions: no stimulation, lipopolysaccharide (LPS), and interleukin-4 (IL-4) from 0 to 14 days. Specimens from each group were evaluated for cellular interactions, inflammatory mediators (IL-1β, TNF-α, MDC, MIP-1β, MCP-1, IL-6, IL-8, TGF-β1, IL-1RA, IL-10), expression of surface markers (CD80, 206), transcription factors (pSTAT1, pSTAT6) and SCAP differentiation markers (DSPP, DMP-1, and alizarin red) using confocal laser scanning microscopy and multiplex cytokine profiling from 2 to 14 days.

RESULTS

SCAP and macrophages displayed a cytokine-mediated interaction and differentiation characteristics. The increased pro-inflammatory cytokines/chemokines: IL-1β, TNF-α, MDC and MIP-1β in the earlier phase followed by the higher ratio of pSTAT6/pSTAT1 and decreased CD206 (p<0.05), indicated a distinct polarization behavior in macrophages during repair in LPS group. Conversely, the equal ratio of pSTAT6/pSTAT1, late increase in CD206 and amplified secretion of IL-1RA, IL-10 and TGF-β1 (p<0.05) in the anti-inflammatory environment, directed alternative macrophage polarization, promoting SCAP differentiation and tissue modeling in IL-4 group.

CONCLUSIONS

The novel 3D organoid system developed in this study allowed a comprehensive analysis of the SCAP-macrophage interactions during inflammation and healing, providing a deeper insight on the periapical dynamics of immature tooth.

Acceleration of pelvic tissue generation by overexpression of basic fibroblast growth factor in stem cells

BACKGROUND

Pelvic organ prolapse (POP) is a common debilitating condition affecting approximately 30-40% of women. The FDA issued a warning about polypropylene mesh used for pelvic floor repair due to erosion, exposure and other complications and banned it in 2019. The application of stem cell therapy and growth factors has strongly promoted the development of pelvic tissue engineering.

PURPOSE

we intend to address the issues of direct application of growth factors, the side effects of long-term exogenous treatment, and the directional differentiation of stem cells. Methods: we evaluated the paracrine effects and directional differentiation of adipose mesenchymal stem cells through stable overexpression of basic fibroblast growth factor (bFGF).

RESULTS

we found that the modified stem cells could continuously and stably release bFGF in the initial stage and could spontaneously differentiate into fibroblasts with a high differentiation efficiency in the later stage.

CONCLUSION

following ADSCs are designed to continuously release controllable levels of growth factors during the control period of repair, taking advantage of the paracrine function of stem cells to accelerate cell growth and extracellular matrix (ECM) reconstruction during the early stage of stem cell implantation, and then stem cells are differentiated into target tissues-fibroblasts to accelerate the reconstruction of pelvic floor tissues, this study demonstrated the strong therapeutic potential of this approach for pelvic tissue engineering.

ABBREVIATIONS

POP: Pelvic organ prolapse; ADSCs: Adipose-derived stem cells; bFGF: Basic fibroblast growth factor; BMSCs: Bone marrow-derived mesenchymal stem cells; HUVECs: Human umbilical vein endothelial cells; EMSCs: Endometrial mesenchymal stem cells; VEGF: Vascular endothelial growth factor; PDGF: Platelet-derived growth factor ECM: Extracellular matrix; IGF: Insulin-like growth factor; HGF: Hepatocyte growth factor; EGF: Epidermal growth factor; BMP-2: Bone morphogenetic protein 2; FBR: Foreign body reaction.

Thymoquinone-Mediated Modulation of Toll-like Receptors and Pluripotency Factors in Gingival Mesenchymal Stem/Progenitor Cells

Thymoquinone (TQ), the key active component of Nigella sativa (NS), demonstrates very promising biomedical anti-inflammatory, antioxidant, antimicrobial and anticancer properties. Several investigations have inspected the modulative activities of TQ on different stem/progenitor cell types, but its possible role in the regulation of gingival mesenchymal stem/progenitor cells (G-MSCs) has not yet been characterized. For the first time, this study investigates the effects of TQ on G-MSCs’ stemness and Toll-like receptor expression profiles. G-MSCs (n = 5) were isolated, sorted via anti-STRO-1 antibodies and then disseminated on cell culture dishes to create colony-forming units (CFUs), and their stem/progenitor cell attributes were characterized. TQ stimulation of the G-MSCs was performed, followed by an examination of the expression of pluripotency-related factors using RT-PCR and the expression profiles of TLRs 1−10 using flowcytometry, and they were compared to a non-stimulated control group. The G-MSCs presented all the predefined stem/progenitor cells’ features. The TQ-activated G-MSCs displayed significantly higher expressions of TLR3 and NANOG with a significantly reduced expression of TLR1 (p < 0.05, Wilcoxon signed-rank test). TQ-mediated stimulation preserves G-MSCs’ pluripotency and facilitates a cellular shift into an immunocompetent-differentiating phenotype through increased TLR3 expression. This characteristic modulation might impact the potential therapeutic applications of G-MSCs.

Immunomodulatory Activity of Mesenchymal Stem Cells in Lupus Nephritis: Advances and Applications

Lupus nephritis (LN) is a significant cause of various acute and chronic renal diseases, which can eventually lead to end-stage renal disease. The pathogenic mechanisms of LN are characterized by abnormal activation of the immune responses, increased cytokine production, and dysregulation of inflammatory signaling pathways. LN treatment is an important issue in the prevention and treatment of systemic lupus erythematosus. Mesenchymal stem cells (MSCs) have the advantages of immunomodulation, anti-inflammation, and anti-proliferation. These unique properties make MSCs a strong candidate for cell therapy of autoimmune diseases. MSCs can suppress the proliferation of innate and adaptive immune cells, such as natural killer cells (NKs), dendritic cells (DCs), T cells, and B cells. Furthermore, MSCs suppress the functions of various immune cells, such as the cytotoxicity of T cells and NKs, maturation and antibody secretion of B cells, maturation and antigen presentation of DCs, and inhibition of cytokine secretion, such as interleukins (ILs), tumor necrosis factor (TNF), and interferons (IFNs) by a variety of immune cells. MSCs can exert immunomodulatory effects in LN through these immune functions to suppress autoimmunity, improve renal pathology, and restore kidney function in lupus mice and LN patients. Herein, we review the role of immune cells and cytokines in the pathogenesis of LN and the mechanisms involved, as well as the progress of research on the immunomodulatory role of MSCs in LN.

Exosomes: a new way of protecting and regenerating optic nerve after injury

As an important part of the central nervous system (CNS), the optic nerve usually cannot regenerate directly after injury. Therefore, treating the injury and restoring the function of the optic nerve are a historical problem in the medical field. Due to the special anatomical position of the optic nerve, the microenvironment needed for protection and regeneration after injury is lacking. Therefore, preventing the continued loss of neurons, protecting the functional nerves, and promoting the effective protection of nerves are the main ways to solve the problem. Exosomes are nano-sized vesicles with a diameter of 30-150 nm, composed of lipid bilayers, proteins, and genetic material. They have key functions in cell-to-cell communication, immune regulation, inflammation, and regeneration. More and more shreds of evidence show that exosomes not only play an important role in systemic diseases such as cancer, cardiovascular diseases, and brain diseases; they also play a key role in ophthalmological diseases. This article reviews the role of exosomes in the protection and regeneration of the optic nerve after optic nerve injury in related experimental studies and clinical treatment methods. GRAPHICAL ABSTARCT: .

Shining the light on clinical application of mesenchymal stem cell therapy in autoimmune diseases

The autoimmune diseases are associated with the host immune system, chronic inflammation, and immune reaction against self-antigens, which leads to the injury and failure of several tissues. The onset of autoimmune diseases is related to unbalanced immune homeostasis. Mesenchymal stem cells (MSCs) are multipotent cells which have capability to self-renew and differentiate into various cell types that exert a critical role in immunomodulation and regenerative therapy. Under the certain condition in vitro, MSCs are able to differentiate into multiple lineage such as osteoblasts, adipocytes, and neuron-like cells. Consequently, MSCs have a valuable application in cell treatment. Accordingly, in this review we present the last observations of researches on different MSCs and their efficiency and feasibility in the clinical treatment of several autoimmune disorders including rheumatoid arthritis, type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, inflammatory bowel disease, autoimmune liver disease, and Sjogren’s syndrome.

Mesenchymal stem cells and natural killer cells interaction mechanisms and potential clinical applications

Natural killer cells (NK cells) are innate immune cells that are activated to fight tumor cells and virus-infected cells. NK cells also play an important role in the graft versus leukemia response. However, they can over-develop inflammatory reactions by secreting inflammatory cytokines and increasing Th1 differentiation, eventually leading to tissue damage. Today, researchers have attributed some autoimmune diseases and GVHD to NK cells. On the other hand, it has been shown that mesenchymal stem cells (MSCs) can modulate the activity of NK cells, while some researchers have shown that NK cells can cause MSCs to lysis. Therefore, we considered it is necessary to investigate the effect of these two cells and their signaling pathway in contact with each other, also their clinical applications.