Application of extracellular vesicles derived from mesenchymal stem cells as potential therapeutic tools in autoimmune and rheumatic diseases

Irradiated umbilical cord mesenchymal stem cell-coated high oxygen-permeable hydrogel lenses inhibit corneal inflammation and neovascularization after corneal alkali burns

Corneal alkali burns can cause persistent inflammation and corneal neovascularization. In this study, we divided corneal alkali burned rabbits into the untreated group, the blank lens group, the radiation-treated umbilical cord mesenchymal stem cells (UCMSC) lens group, and the UCMSC I.V. group, and then measured corneal inflammation, neovascularization and corneal injury repair via slit lamp microscopy, captured anterior segment optical coherence tomography (AS-OCT), and performed hematoxylin-eosin staining. Compared with those in the other experimental groups, radiation-treated UCMSC lenses significantly decreased inflammatory index (IF) scores, areas of corneal blood vessels and corneal epithelial injury. The expression of interleukin (IL)-17 in corneas treated with radiation-treated UCMSC lenses was lower than that in corneas treated with blank lenses, and radiation-treated UCMSC lenses exhibited greater expression of IL-4 and signal transducer and activator of transcription 1 (STAT1), while the expression of cluster of differentiation-3G (CD3G), a linker for the activation of T cells (LAT), IL-6, IL-1B, CC chemokine receptor 6 (CCR6) and IL-23 exhibited the opposite effects (all P < 0.05). Our findings demonstrated that irradiated UCMSC-coated high oxygen-permeable hydrogel lenses on the ocular surface inhibited corneal angiogenesis and inflammation after corneal alkaline burns. The downregulation of Th17 cell differentiation might be responsible for these effects.

Effects of Hydrogels on Mesenchymal Stem/Stromal Cells Paracrine Activity and Extracellular Vesicles Production

Mesenchymal stem/stromal cells (MSCs) are a valuable source of paracrine factors, as they have a remarkable secretory capacity, and there is a sizeable knowledge base to develop industrial and clinical production protocols. Promising cell-free approaches for tissue regeneration and immunomodulation are driving research towards secretome applications, among which extracellular vesicles (EVs) are steadily gaining attention. However, the manufacturing and application of EVs is limited by insufficient yields, knowledge gaps, and low standardization. Facing these limitations, hydrogels represent a versatile three-dimensional (3D) culture platform that can incorporate extracellular matrix (ECM) components to mimic the natural stem cell environment in vitro; via these niche-mimicking properties, hydrogels can regulate MSCs' morphology, adhesion, proliferation, differentiation and secretion capacities. However, the impact of the hydrogel's architectural, biochemical and biomechanical properties on the production of EVs remains poorly understood, as the field is still in its infancy and the interdependency of culture parameters compromises the comparability of the studies. Therefore, this review summarizes and discusses the reported effects of hydrogel encapsulation and culture on the secretion of MSC-EVs. Considering the effects of cell-material interactions on the overall paracrine activity of MSCs, we identify persistent challenges from low standardization and process control, and outline future paths of research, such as the synergic use of hydrogels and bioreactors to enhance MSC-EV generation.

The promise of mesenchymal stromal/stem cells in erectile dysfunction treatment: a review of current insights and future directions

Erectile dysfunction is a common and multifactorial condition that significantly impacts men's quality of life. Traditional treatments, such as phosphodiesterase type 5 inhibitors (PDE5i), often fail to provide lasting benefits, particularly in patients with underlying health conditions. In recent years, regenerative medicine, particularly stem cell therapies, has emerged as a promising alternative for managing erectile dysfunction. This review explores the potential of mesenchymal stromal/stem cells (MSCs) and their paracrine effects, including extracellular vesicles (EVs), in the treatment of erectile dysfunction. MSCs have shown remarkable potential in promoting tissue repair, reducing inflammation, and regenerating smooth muscle cells, offering therapeutic benefits in models of erectile dysfunction. Clinical trials have demonstrated positive outcomes in improving erectile function and other clinical parameters. This review highlights the promise of MSC therapy for erectile dysfunction, discusses existing challenges, and emphasizes the need for continued research to refine these therapies and improve long-term patient outcomes.

Mesenchymal Stromal Cell-Based Therapy: A Promising Approach for Autoimmune Diseases

Autoimmune diseases are characterized by immune dysregulation, resulting in aberrant reactivity of T cells and antibodies to self-antigens, leading to various patterns of inflammation and organ dysfunction. However, current therapeutic agents exhibit broad-spectrum activity and lack disease-specific selectivity, leading to enduring adverse effects, notably severe infections, and malignancies, and patients often fail to achieve the intended clinical goals. Mesenchymal stromal cells (MSCs) are multipotent stromal cells that can be easily derived from various tissues, such as adipose tissue, umbilical cords, Wharton's jelly, placenta, and dental tissues. MSCs offer advantages due to their immunomodulatory and anti-inflammatory abilities, low immunogenicity, and a high capacity for proliferation and multipotent differentiation, making them excellent candidates for cell-based treatment in autoimmune disorders. This review will cover preclinical studies and clinical trials involving MSCs in autoimmune diseases, as well as the primary challenges associated with the clinical application of MSC therapies and strategies for maximizing their therapeutic potential.

Potential therapeutic effects and nano-based delivery systems of mesenchymal stem cells and their isolated exosomes to alleviate acute respiratory distress syndrome caused by COVID-19

The severe respiratory effects of the coronavirus disease 2019 (COVID-19) pandemic have necessitated the immediate development of novel treatments. The majority of COVID-19-related fatalities are due to acute respiratory distress syndrome (ARDS). Consequently, this virus causes massive and aberrant inflammatory conditions, which must be promptly managed. Severe respiratory disorders, notably ARDS and acute lung injury (ALI), may be treated safely and effectively using cell-based treatments, mostly employing mesenchymal stem cells (MSCs). Since the high potential of these cells was identified, a great deal of research has been conducted on their use in regenerative medicine and complementary medicine. Multiple investigations have demonstrated that MSCs and their products, especially exosomes, inhibit inflammation. Exosomes serve a critical function in intercellular communication by transporting molecular cargo from donor cells to receiver cells. MSCs and their derived exosomes (MSCs/MSC-exosomes) may improve lung permeability, microbial and alveolar fluid clearance, and epithelial and endothelial repair, according to recent studies. This review focuses on COVID-19-related ARDS clinical studies involving MSCs/MSC-exosomes. We also investigated the utilization of Nano-delivery strategies for MSCs/MSC-exosomes and anti-inflammatory agents to enhance COVID-19 treatment.

Extracellular vesicles: immunomodulation, diagnosis, and promising therapeutic roles for rheumatoid arthritis

Extracellular vesicles (EV) can be produced as part of pathology and physiology with increased amounts in pathological conditions. EVs can carry and transfer cargo such as proteins, nucleic acids, and lipids to target cells and mediate intercellular communication resulting in modulation of gene expression, signaling pathways, and phenotype of recipient cells. EVs greatly influence the extracellular environment and the immune response. Their immunomodulatory properties are crucial in rheumatoid arthritis (RA), a condition marked by dysregulated immune response. EVs can modulate the functions of innate and adaptive immune cells in RA pathogenesis. Differentially expressed EV-associated molecules in RA, such as microRNAs (miRNAs), long-noncoding RNAs (lncRNAs), messenger RNAs (mRNAs) and proteins are promising markers to diagnose the disease. miRNA, lncRNA, and circular RNA (circRNA) cargos in EV regulate inflammation and the pathogenic functions of RA fibroblast-like synoviocytes (RA-FLS). Downregulated molecules in RA tissue and drugs can be encapsulated in EVs for RA therapy. This review provides an updated overview of EVs' immunomodulatory, diagnostic, and therapeutic roles, particularly emphasizing mesenchymal stem cell-derived EVs (MSC-EVs).

Advancements in extracellular vesicle targeted therapies for rheumatoid arthritis: insights into cellular origins, current perspectives, and emerging challenges

Rheumatoid arthritis (RA) remains a challenging chronic autoimmune disorder characterized by persistent joint inflammation and damage. While modern regenerative strategies, encompassing cell/stem cell-based therapies, gene therapy, and tissue engineering, have advanced tissue repair efforts, a definitive cure for RA remains elusive. Consequently, there is growing interest in developing targeted therapies that directly address the underlying mechanisms driving RA pathogenesis, such as extracellular vesicles (EVs). These small membrane-bound particles can modulate immune responses within the inflammatory microenvironment of damaged cartilage. To launch the clinical potential of EVs, they can be isolated from various cell types through several techniques. EVs can carry various bioactive molecules and anti-inflammatory or pro-regenerative drugs, deliver them directly to the affected joints, and affect the behavior of injured cells, making them a compelling choice for targeted therapy and drug delivery in RA patients. However, there are still several challenges and limitations associated with EV-based therapy, including the absence of standardized protocols for EV isolation, characterization, and delivery. This review provides a comprehensive overview of the cellular sources of EVs in RA and delves into their therapeutic potential and the hurdles they must overcome.

Understanding molecular characteristics of extracellular vesicles derived from different types of mesenchymal stem cells for therapeutic translation

Mesenchymal stem cells (MSCs) have been studied for decades as candidates for cellular therapy, and their secretome, including secreted extracellular vesicles (EVs), has been identified to contribute significantly to regenerative and reparative functions. Emerging evidence has suggested that MSC-EVs alone, could be used as therapeutics that emulate the biological function of MSCs. However, just as with MSCs, MSC-EVs have been shown to vary in composition, depending on the tissue source of the MSCs as well as the protocols employed in culturing the MSCs and obtaining the EVs. Therefore, the importance of careful choice of cell sources and culture environments is receiving increasing attention. Many factors contribute to the therapeutic potential of MSC-EVs, including the source tissue, isolation technique, and culturing conditions. This review illustrates the molecular landscape of EVs derived from different types of MSC cells along with culture strategies. A thorough analysis of publicly available omic datasets was performed to advance the precision understanding of MSC-EVs with unique tissue source-dependent molecular characteristics. The tissue-specific protein and miRNA-driven Reactome ontology analysis was used to reveal distinct patterns of top Reactome ontology pathways across adipose, bone marrow, and umbilical MSC-EVs. Moreover, a meta-analysis assisted by an AI technique was used to analyze the published literature, providing insights into the therapeutic translation of MSC-EVs based on their source tissues.

What is the rationale for mesenchymal stromal cells based therapies in the management of hemophilic arthropathies?

Hemophilia A and B are rare X-linked genetic bleeding disorders due to a complete or partial deficiency in the coagulation factors VIII or IX, respectively. The main treatment for hemophilia is prophylactic and based on coagulation factor replacement therapies. These treatments have significantly reduced bleeding and improved the patients' quality of life. Nevertheless, repeated joint bleedings (hemarthroses), even subclinical hemarthroses, can lead to hemophilic arthropathy (HA). This disabling condition is characterized by chronic pain due to synovial inflammation, cartilage and bone destruction requiring ultimately joint replacement. HA resembles to rheumatoid arthritis because of synovitis but HA is considered as having similarities with osteoarthritis as illustrated by the migration of immune cells, production of inflammatory cytokines, synovial hypertrophy and cartilage damage. Various drugs have been evaluated for the management of HA with limited success. The objective of the review is to discuss new therapeutic approaches with a special focus on the studies that have investigated the potential of using mesenchymal stromal cells (MSCs) in the management of HA. A systematic review of the literature has been made. Most of the studies have focused on the interest of MSCs for the delivery of missing factors VIII or IX but in some studies, more insight on the effect of MSC injection on synovial inflammation or cartilage structure were provided and put in perspective for possible clinical applications.

A comprehensive insight into the immunomodulatory role of MSCs-derived exosomes (MSC-Exos) through modulating pattern-recognition receptors (PRRs)

Mesenchymal stem cell-derived exosomes (MSC-Exos) are emerging as remarkable agents in the field of immunomodulation with vast potential for diagnosing and treating various diseases, including cancer and autoimmune disorders. These tiny vesicles are laden with a diverse cargo encompassing proteins, nucleic acids, lipids, and bioactive molecules, offering a wealth of biomarkers and therapeutic options. MSC-Exos exhibit their immunomodulatory prowess by skillfully regulating pattern-recognition receptors (PRRs). They conduct a symphony of immunological responses, modulating B-cell activities, polarizing macrophages toward anti-inflammatory phenotypes, and fine-tuning T-cell activity. These interactions have profound implications for precision medicine, cancer immunotherapy, autoimmune disease management, biomarker discovery, and regulatory approvals. MSC-Exos promises to usher in a new era of tailored therapies, personalized diagnostics, and more effective treatments for various medical conditions. As research advances, their transformative potential in healthcare becomes increasingly evident.

A comprehensive review on the role of mesenchymal stromal/stem cells in the management of rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease with systemic manifestations. Although the success of immune modulatory drug therapy is considerable, about 40% of patients do not respond to treatment. Mesenchymal stromal/stem cells (MSCs) have been demonstrated to have therapeutic potential for inflammatory diseases.

AREAS COVERED

This review provides an update on RA disease and on pre-clinical and clinical studies using MSCs from bone marrow, umbilical cord, adipose tissue, and dental pulp, to regulate the immune response. Moreover, the clinical use, safety, limitations, and future perspective of MSCs in RA are discussed. Using the PubMed database and ClincalTrials.gov, peer-reviewed full-text papers, abstracts and clinical trials were identified from 1985 through to April 2023.

EXPERT OPINION

MSCs demonstrated a satisfactory safety profile and potential for clinical efficacy. However, it is mandatory to deepen the investigations on how MSCs affect the proinflammatory deregulated RA patients' cells. MSCs are potentially good candidates for severe RA patients not responding to conventional therapies but a long-term follow-up after stem cells treatment and standardized protocols are needed. Future research should focus on well-designed multicenter randomized clinical trials with adequate sample sizes and properly selected patients satisfying RA criteria for a valid efficacy evaluation.

The Effects of Different Concentrations of Vitamin D3 on Immunological Parameters of Immunosuppressed Rats Induced

Vitamin D3 receptor is expressed in several types of immune cells suggesting that Vitamin D3 could have immune regulatory roles. The current study was conducted to investigate the role of Vitamin D3 in reducing the toxicity of the cisplatin on some Immunological parameters in the rat model. The current experiment was conducted on 80 adult white male rats within the age range of 9-12 weeks. The animals were divided into eight groups (10 animals in each group). The control group was dosed with the physiological solution until the end of experiment (C). Rats in the second treatment were injected with cisplatin (2 mg/kg, T1). Rats in the third (T2), fourth (T3), and fifth (T4) groups were injected with cisplatin at a concentration (2 mg/kg) and received Vitamin D3 at levels of 5000 IU, 10,000 IU, and 15,000 IU, respectively. The rats in the sixth (T5), seventh (T6), and eighth (T7) groups were subjected to Vitamin D3 at concentrations of 5000 IU,10,000 IU, and 15,000 IU, respectively. At the end of the experiment, which lasted 21 days, the animals were anesthetized, their weights were recorded, and blood samples were collected. The findings revealed a significant elevation in the levels of interleukin-12, tumor necrosis factor-alpha, C-reactive protein, lymphocyte percentage, monocyte percentage, and eosinophil percentage within group T1 compared to the control and other treatment groups that received Vitamin D3. The average percentage of white blood cells and neutrophils in group T1 was significantly lesser than other groups. It can be concluded that supplementation of different Vitamin D3 levels (5000-10,000 IU) have positive influences on the immunological parameters of immunosuppressed rats.

Potential Therapeutic Application and Mechanism of Action of Stem Cell-Derived Extracellular Vesicles (EVs) in Systemic Lupus Erythematosus (SLE)

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease that affects nearly 3.41 million people globally, with 90% of the cases affecting women of childbearing age. SLE is a complex disease due to the interplay of various immunological pathways and mechanisms. This scoping review aims to highlight the latest research findings on the therapeutic mechanisms of action of EVs in SLE. Relevant research articles were identified using the PRISMA framework from databases such as PubMed/MEDLINE (National Library of Medicine), Scopus (Elsevier), and Web of Science: Core Collection (Clarivate Analytics) from July 2023 to October 2023. Eleven studies met the inclusion criteria and thus were included in this scoping review. The findings showed that EVs have therapeutic effects on ameliorating the disease progression of SLE. EVs can reduce the pro-inflammatory cytokines and increase the anti-inflammatory cytokines. Moreover, EVs can increase the levels of regulatory T cells, thus reducing inflammation. EVs also have the potential to regulate B cells to alleviate SLE and reduce its adverse effects. The scoping review has successfully analysed the therapeutic potential in ameliorating the disease progression of SLE. The review also includes prospects to improve the effects of EVs further to increase the therapeutic effects on SLE.

Understanding exosomes: Part 2-Emerging leaders in regenerative medicine

Exosomes are the smallest subset of extracellular signaling vesicles secreted by most cells with the ability to communicate with other tissues and cell types over long distances. Their use in regenerative medicine has gained tremendous momentum recently due to their ability to be utilized as therapeutic options for a wide array of diseases/conditions. Over 5000 publications are currently being published yearly on this topic, and this number is only expected to dramatically increase as novel therapeutic strategies continue to be developed. Today exosomes have been applied in numerous contexts including neurodegenerative disorders (Alzheimer's disease, central nervous system, depression, multiple sclerosis, Parkinson's disease, post-traumatic stress disorders, traumatic brain injury, peripheral nerve injury), damaged organs (heart, kidney, liver, stroke, myocardial infarctions, myocardial infarctions, ovaries), degenerative processes (atherosclerosis, diabetes, hematology disorders, musculoskeletal degeneration, osteoradionecrosis, respiratory disease), infectious diseases (COVID-19, hepatitis), regenerative procedures (antiaging, bone regeneration, cartilage/joint regeneration, osteoarthritis, cutaneous wounds, dental regeneration, dermatology/skin regeneration, erectile dysfunction, hair regrowth, intervertebral disc repair, spinal cord injury, vascular regeneration), and cancer therapy (breast, colorectal, gastric cancer and osteosarcomas), immune function (allergy, autoimmune disorders, immune regulation, inflammatory diseases, lupus, rheumatoid arthritis). This scoping review is a first of its kind aimed at summarizing the extensive regenerative potential of exosomes over a broad range of diseases and disorders.

What do osteoporosis and osteoarthritis have in common? An integrated study of overlapping differentially expressed genes in bone mesenchymal stem cells of osteoporosis and osteoarthritis

OBJECTIVE

For identification of aberrantly expressed genes in mesenchymal stem cells of osteoporosis (OP) and osteoarthritis (OA), Gene Expression Omnibus (GEO) datasets were integrated to investigate the intersection point.

METHODS

GSE35958 (osteoporosis) and GSE19664 (osteoarthritis) datasets were obtained from GEO database. The abnormally expressed genes were analyzed by GEO2R. Functional enrichment was explored by Metascape database and R software. The String database and Cytoscape software were used to build the protein-protein interaction network and identify hub genes. GSE35957 and GSE116925 were used as verification datasets. Single-cell analysis and pseudotime analysis were undertaken. CTDbase, Network Analyst, HPA database, HERB database and MIRW database were used to research the information, tissue and cell distribution, regulation, interaction and ingredients targeting the hub genes. Additionally, in vitro experiments such as RT-PCR, ALP staining and immunofluorescence were undertaken as verification tests.

RESULTS

Ten hub genes were identified in this study. All these genes play an important role in bone or cartilage generation. They have diagnostic values and therapeutic potential for OA and OP. Single-cell analysis visualized the cell distribution and pseudotime distribution of these genes. Some potential therapeutic ingredients of these genes were identified, such as curcumin, wogonin and glycerin. In vitro experiments, RT-PCR results showed that COL9A3 and MMP3 were downregulated and PTH1R was upregulated during osteogenic induction of BMSC. Immunohistochemical results showed the expression trend of MMP3 and COL2A1.

CONCLUSION

Ten abnormal hub genes of osteoporosis and osteoarthritis were identified successfully by this study. They were important regulatory genes for healthy bone and cartilage. These genes could be the common connections between osteoporosis and osteoarthritis as well as treatment targets. Further study of the regulatory mechanism and treatment effects of these genes would be valuable. The results of this study could contribute to further research.

MESENCHYMAL STEM CELLS: EXOSOMES AND CONDITIONED MEDIA AS INNOVATIVE STRATEGIES IN THE TREATMENT OF PATIENTS WITH AUTOIMMUNE DISEASES

Introduction. Autoimmune diseases are a class of immunopathological conditions heterogeneous in clinical manifestations, characterized by immune disorders that cause the loss of the body's autoimmune tolerance and, as a result, abnormal reactivity of B-cells and T-cells, which leads to damage to own tissues. Today, about 10% of the population suffers from diseases of this class, which are clinically manifested in the form of more than 80 forms of autoimmune diseases. The aim of the study. Summarize current ideas about the therapeutic potential of conditioned media and exosomes of MSCs in the treatment of patients with autoimmune diseases based on data from open sources of information. Materials and methods. Publications were selected based on PubMed, Clinical Key Elsevier, Cochrane Library, eBook Business Collection and Google Scholar databases, which covered information on the use of conditioned media and MSC exosomes in the treatment of diseases of premature newborns using the Keywords: mesenchymal stem cells, conditioned media, secretion, autoimmune diseases. Results. The technical complexity and high costs associated with the production and regulatory approval procedures of MSC therapy create barriers to their clinical use. Studies have shown that the cell-free secretome of MSCs, which consists of a wide range of growth factors, cytokines, chemokines and extracellular vesicles, exhibits a pluripotent effect. Today, extracellular vesicles are classified according to their diameter into apoptotic bodies (>1000 nm), microvesicles (100–1000 nm) and exosomes (30–150 nm). Exosome activity can be easily manipulated by preconditioning MSCs, by simply adding cytokines or chemicals to the culture medium, by introducing gene modifications, or by using hypoxic culture conditions. A number of studies have demonstrated the comparable effectiveness of conditioned media and MSC exosomes in the treatment of patients with autoimmune diseases. Conclusions. Exosomes and conditioned media with MSCs have the potential to replace cell therapy or serve as a comparable clinical strategy to biological therapy in neonatology. MSC preconditioning will allow modulating the therapeutic effects of exosomes and will become the basis for establishing recommendations and standards for effective and safe cell-free therapy.

Qasim M. Study of some genetic and molecular markers for some rheumatoid arthritis patients in Iraq

Rheumatoid arthritis is an autoimmune disorder, and genetic factors strongly contribute to a genetic predisposition to developing the disease. This study evaluated the genetic and molecular indicators of some Iraqi patients with rheumatoid arthritis. The study included (100) patients with rheumatoid arthritis with (100) healthy individuals who attended Al-Hussain General Teaching Hospital, Department of Arthritis and Joints Centre, al Blood Bank in Baghdad for the period from the beginning of January 2022 until the end of March 2022. The patients were diagnosed under the supervision of medical committees specialized in joint diseases. The human leukocyte antigen is one of the essential genetic factors in regulating the immune response, as these antigens contribute to the susceptibility to disease. Human leukocyte antigen (HLA) class II (Class-II- HLA-DR, -DQ) was genotyped using lymphocytotoxicity assay and PCR-SSP method. The results showed that there was a significant increase in the recurrence of human leukocyte antigens (DR4 R53) in rheumatoid arthritis patients compared to the healthy ones, as well as an increase in the recurrence of human leukocyte antigens (HLA-DQ3) with a significant difference in rheumatoid arthritis patients compared to the healthy ones. Regarding HLA-DRB1 and -DQB1 alleles, it was found that there was a significant increase in the frequency of HLA-DRB1*04 (01-22, not 0415) compared to healthy controls, while the percentage of HLA-DRB1*0701 alleles was less frequent in patients compared to healthy controls. Moreover, the frequency of HLADQB1*03(02,07) alleles was high in the patients compared to the healthy ones, while HLA-DQB1*0303 showed a highly significant difference in the healthy group compared to the patients. Keywords: Rheumatoid arthritis, genetic factors, HLA-DRB1, -DQB1 alleles, PCR.

Treatment of shallow and deep white spot lesions with three different mouthwashes evaluated by laser fluorescence (an in vitro study)

This research aims to find how three different types of mouthwashes affect the depth of artificial white spot lesions. Teeth with various depths of white spot lesions were immersed in either splat mouthwash, Biorepair mouthwash, Sensodyne mouthwash, or artificial saliva (control)twice daily for one minute for 4 weeks and 8 weeks at 37°C. After this immersion procedure, lesion depth was measured using a diagnosed pen score. A one-way analysis of variance, Dunnett T3 and Tukey's post hoc α = .05 were used to analyze the testing data. Splat mouthwash enhanced the WSL remineralization and made the lowest ΔF compared with other mouthwashes in shallow and deep enamel after 4 and 8 weeks of treatment. In the repair groups, after 4 weeks of treatment, significant recovery was observed in shallow enamel. Further improvement in shallow WSL after 8 weeks of treatment with biorepair mouthwash was observed compared to Sensodyne and the control group. Splat mouthwash is more effective than other mouthwashes in remineralizing two depths of WSLs at different time points. Keywords: DIAGNOdent pen, Shallow enamel, Deep enamel, white spot lesion.

Knowledge mapping of extracellular vesicles in wound healing: A bibliometric analysis (2002-2022)

Extracellular vesicles in wound healing have become an active research field with substantial value and potential. Nevertheless, there are few bibliometric studies in this field. We aimed to visualise the research hot spots and trends of extracellular vesicles in wound healing using a bibliometric analysis to help understand the future development of basic and clinical research. The articles and reviews regarding extracellular vesicles in the wound healing were selected from the Web of Science Core Collection. VOSviewers, CiteSpace and R package "bibliometric" were used to conduct this bibliometric analysis. A total of 1225 articles from 56 countries led by China and the United States were included. The number of publications related to extracellular vesicles increased year by year. Shanghai Jiaotong University, Huazhong University of Science and Technology, Sun Yat-sen University and Central South University are the main research institutions. International Journal of Molecular Sciences is the most popular journal in this field, while Stem Cell Research & Therapy is the most frequently cited journal. These papers come from 7546 authors, among which Zhang Wei has published the most papers and Zhang Bin has the most cocited papers. The research on the treatment strategy of extracellular vesicles in the process of wound healing is the main topic in this field. "exosomes", "miRNA", "angiogenesis", "regenerative medicine", "inflammation" and "diabetic wound" are the main key words of emerging research hotspots. This is the first bibliometric study, which comprehensively summarises the research trend and development of extracellular vesicles and exocrine bodies in wound healing. These informations determine the latest research frontiers and hot directions, and provide reference for the study of extracellular vesicles and exosomes.

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.

Pathological role of inflammation in ocular disease progress and its targeting by mesenchymal stem cells (MSCs) and their exosome; current status and prospect

Because of their unique capacity for differentiation to a diversity of cell lineages and immunosuppressive properties, mesenchymal stem cells (MSC) are being looked at as a potential new treatment option in ophthalmology. The MSCs derived from all tissue sources possess immunomodulatory attributes through cell-to-cell contact and releasing a myriad of immunomodulatory factors (IL-10, TGF-β, growth-related oncogene (GRO), indoleamine 2,3 dioxygenase (IDO), nitric oxide (NO), interleukin 1 receptor antagonist (IL-1Ra), prostaglandin E2 (PGE2)). Such mediators, in turn, alter both the phenotype and action of all immune cells that serve a pathogenic role in the progression of inflammation in eye diseases. Exosomes from MSCs, as natural nano-particles, contain the majority of the bioactive components of parental MSCs and can easily by-pass all biological barriers to reach the target epithelial and immune cells in the eye without interfering with nearby parenchymal cells, thus having no serious side effects. We outlined the most recent research on the molecular mechanisms underlying the therapeutic benefits of MSC and MSC-exosome in the treatment of inflammatory eye diseases in the current article.

Role of miRNAs in Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease characterized by autoimmunity, synovial inflammation and joint destruction. Pannus formation in the synovial cavity can cause irreversible damage to the joint and cartilage and eventually permanent disability. Current conventional treatments for RA have limitations regarding efficacy, safety and cost. microRNA (miRNA) is a type of non-coding RNA (ncRNA) that regulates gene expression at the post-transcriptional level. The dysregulation of miRNA has been observed in RA patients and implicated in the pathogenesis of RA. miRNAs have emerged as potential biomarkers or therapeutic agents. In this review, we explore the role of miRNAs in various aspects of RA pathophysiology, including immune cell imbalance, the proliferation and invasion of fibroblast-like synovial (FLS) cell, the dysregulation of inflammatory signaling and disturbance in angiogenesis. We delve into the regulatory effects of miRNAs on Treg/Th17 and M1/M2 polarization, the activation of the NF-κB/NLRP3 signaling pathway, neovascular formation, energy metabolism induced by FLS-cell-induced energy metabolism, apoptosis, osteogenesis and mobility. These findings shed light on the potential applications of miRNAs as diagnostic or therapeutic biomarkers for RA management. Furthermore, there are some strategies to regulate miRNA expression levels by utilizing miRNA mimics or exosomes and to hinder miRNA activity via competitive endogenous RNA (ceRNA) network-based antagonists. We conclude that miRNAs offer a promising avenue for RA therapy with unlimited potential.

Emerging role of mesenchymal stem/stromal cells (MSCs) and MSCs-derived exosomes in bone- and joint-associated musculoskeletal disorders: a new frontier

Exosomes are membranous vesicles with a 30 to 150 nm diameter secreted by mesenchymal stem/stromal cells (MSCs) and other cells, such as immune cells and cancer cells. Exosomes convey proteins, bioactive lipids, and genetic components to recipient cells, such as microRNAs (miRNAs). Consequently, they have been implicated in regulating intercellular communication mediators under physiological and pathological circumstances. Exosomes therapy as a cell-free approach bypasses many concerns regarding the therapeutic application of stem/stromal cells, including undesirable proliferation, heterogeneity, and immunogenic effects. Indeed, exosomes have become a promising strategy to treat human diseases, particularly bone- and joint-associated musculoskeletal disorders, because of their characteristics, such as potentiated stability in circulation, biocompatibility, low immunogenicity, and toxicity. In this light, a diversity of studies have indicated that inhibiting inflammation, inducing angiogenesis, provoking osteoblast and chondrocyte proliferation and migration, and negative regulation of matrix-degrading enzymes result in bone and cartilage recovery upon administration of MSCs-derived exosomes. Notwithstanding, insufficient quantity of isolated exosomes, lack of reliable potency test, and exosomes heterogeneity hurdle their application in clinics. Herein, we will deliver an outline respecting the advantages of MSCs-derived exosomes-based therapy in common bone- and joint-associated musculoskeletal disorders. Moreover, we will have a glimpse the underlying mechanism behind the MSCs-elicited therapeutic merits in these conditions.

Muscle-derived extracellular vesicles improve disuse-induced osteoporosis by rebalancing bone formation and bone resorption

Osteoporosis is a highly prevalent skeletal bone disorder worldwide with characteristics of reduced bone mass and increased risk of osteoporotic fractures. It has been predicted to become a global challenge with the aging of the world population. However, the current therapy based on antiresorptive drugs and anabolic drugs has unwanted side effects. Although cell-based treatments have shown therapeutic effects for osteoporosis, there are still some limitations inhibiting the process of clinical application. In the present study, we developed EVs derived from skeletal muscle tissues (Mu-EVs) as a cell-free therapy to treat disuse-induced osteoporosis. Our results showed that Mu-EVs could be prepared easily and abundantly from skeletal muscle tissues, and that these Mu-EVs had typical features of extracellular vesicles. In vitro studies demonstrated that Mu-EVs from normal skeletal muscles could be phagocytized by bone marrow stromal/stem cells (BMSCs) and osteoclasts (OCs), and promoted osteogenic differentiation of BMSCs while inhibited OCs formation. Correspondingly, Mu-EVs from atrophic skeletal muscles attenuated the osteogenesis of BMSCs and strengthened the osteoclastogenesis of monocytes. In vivo experiments revealed that Mu-EVs could efficiently reverse disuse-induced osteoporosis by enhancing bone formation and suppressing bone resorption. Collectively, our results suggest that Mu-EVs may be a potential cell-free therapy for osteoporosis treatment. STATEMENT OF SIGNIFICANCE: Osteoporosis is a highly prevalent skeletal bone disorder worldwide and has become a global health concern with the aging of the world population. The current treatment for osteoporosis has unwanted side effects. Extracellular veiscles (EVs) from various cell sources are a promising candidate for osteoporosis treatment. In the present study, our team established protocols to isolate EVs from culture supernatant of skeletal muscles (Mu-EVs). Uptake of Mu-EVs by BMSCs and osteoclasts influences the balance of bone remodeling via promoting the osteogenic differentiation of BMSCs and inhibiting the osteoclasts formation of monocytes. In addition, exogenous Mu-EVs from normal skeletal muscles are proved to reverse the disuse-induced osteoporosis. We provide experimental evidence that Mu-EVs therapy is a potential cell-free platform for osteoporosis treatment towards clinical application.

Extracellular vesicles derived from host and gut microbiota as promising nanocarriers for targeted therapy in osteoporosis and osteoarthritis

Osteoporosis (OP), a systemic bone disease that causes structural bone loss and bone mass loss, is often associated with fragility fractures. Extracellular vesicles (EVs) generated by mammalian and gut bacteria have recently been identified as important mediators in the intercellular signaling pathway that may play a crucial role in microbiota-host communication. EVs are tiny membrane-bound vesicles, which range in size from 20 to 400 nm. They carry a variety of biologically active substances across intra- and intercellular space. These EVs have developed as a promising research area for the treatment of OP because of their nanosized architecture, enhanced biocompatibility, reduced toxicity, drug loading capacity, ease of customization, and industrialization. This review describes the latest development of EVs derived from mammals and bacteria, including their internalization, isolation, biogenesis, classifications, topologies, and compositions. Additionally, breakthroughs in chemical sciences and the distinctive biological features of bacterial extracellular vesicles (BEVs) allow for the customization of modified BEVs for the therapy of OP. In conclusion, we give a thorough and in-depth summary of the main difficulties and potential future of EVs in the treatment of OP, as well as highlight innovative uses and choices for the treatment of osteoarthritis (OA).

Novel potential therapeutic targets of alopecia areata

Alopecia areata (AA) is a non-scarring hair loss disorder caused by autoimmunity. The immune collapse of the hair follicle, where interferon-gamma (IFN-γ) and CD8+ T cells accumulate, is a key factor in AA. However, the exact functional mechanism remains unclear. Therefore, AA treatment has poor efficacy maintenance and high relapse rate after drug withdrawal. Recent studies show that immune-related cells and molecules affect AA. These cells communicate through autocrine and paracrine signals. Various cytokines, chemokines and growth factors mediate this crosstalk. In addition, adipose-derived stem cells (ADSCs), gut microbiota, hair follicle melanocytes, non-coding RNAs and specific regulatory factors have crucial roles in intercellular communication without a clear cause, suggesting potential new targets for AA therapy. This review discusses the latest research on the possible pathogenesis and therapeutic targets of AA.

Cellular-Based Therapies in Systemic Sclerosis: From Hematopoietic Stem Cell Transplant to Innovative Approaches

Systemic sclerosis (SSc) is a systemic disease characterized by autoimmune responses, vasculopathy and tissue fibrosis. The pathogenic mechanisms involve a wide range of cells and soluble factors. The complexity of interactions leads to heterogeneous clinical features in terms of the extent, severity, and rate of progression of skin fibrosis and internal organ involvement. Available disease-modifying drugs have only modest effects on halting disease progression and may be associated with significant side effects. Therefore, cellular therapies have been developed aiming at the restoration of immunologic self-tolerance in order to provide durable remissions or to foster tissue regeneration. Currently, SSc is recommended as the 'standard indication' for autologous hematopoietic stem cell transplantation by the European Society for Blood and Marrow Transplantation. This review provides an overview on cellular therapies in SSc, from pre-clinical models to clinical applications, opening towards more advanced cellular therapies, such as mesenchymal stem cells, regulatory T cells and potentially CAR-T-cell therapies.

Regulation of Extracellular Vesicle-Mediated Immune Responses against Antigen-Specific Presentation

Extracellular vesicles (EVs) produced by various immune cells, including B and T cells, macrophages, dendritic cells (DCs), natural killer (NK) cells, and mast cells, mediate intercellular communication and have attracted much attention owing to the novel delivery system of molecules in vivo. DCs are among the most active exosome-secreting cells of the immune system. EVs produced by cancer cells contain cancer antigens; therefore, the development of vaccine therapy that does not require the identification of cancer antigens using cancer-cell-derived EVs may have significant clinical implications. In this review, we summarise the molecular mechanisms underlying EV-based immune responses and their therapeutic effects on tumour vaccination.

Knowledge Mapping of Exosomes in Autoimmune Diseases: A Bibliometric Analysis (2002–2021)

Background

Autoimmune diseases (AIDs) are a class of chronic disabling diseases characterized by inflammation and damage to muscles, joints, bones, and internal organs. Recent studies have shown that much progress has been made in the research of exosomes in AIDs. However, there is no bibliometric analysis in this research field. This study aims to provide a comprehensive overview of the knowledge structure and research hotspots of exosomes in AIDs through bibliometrics.

Method

Publications related to exosomes in AIDs from 2002 to 2021 were searched on the web of science core collection (WoSCC) database. VOSviewers, CiteSpace and R package “bibliometrix” were used to conduct this bibliometric analysis.

Results

312 articles from 48 countries led by China and the United States were included. The number of publications related to exosomes in AIDs is increasing year by year. Central South University, Sun Yat Sen University, Tianjin Medical University and University of Pennsylvania are the main research institutions. Frontiers in immunology is the most popular journal in this field, and Journal of Immunology is the most co-cited journal. These publications come from 473 authors among which Ilias Alevizos, Qianjin Lu, Wei Wei, Jim Xiang and Ming Zhao had published the most papers and Clotilde Théry was co-cited most often. Studying the mechanism of endogenous exosomes in the occurrence and development of AIDs and the therapeutic strategy of exogenous exosomes in AIDs are the main topics in this research field. “Mesenchymal stem cells”, “microRNA”, “biomarkers”, “immunomodulation”, and “therapy” are the primary keywords of emerging research hotspots.

Conclusion

This is the first bibliometric study that comprehensively summarizes the research trends and developments of exosomes in AIDs. This information identifies recent research frontiers and hot directions, which will provide a reference for scholars studying exosomes.

Diagnostic role of dynamic contrast-enhanced magnetic resonance imaging in differentiating breast lesions

OBJECTIVE

This study aimed to assess the diagnostic role of perfusion weighted image (DCE-PWI) to differentiate benign from malignant breast lesions.

PATIENTS AND METHODS

The study comprised 32 women who had mammography and/or breast ultrasonography findings that were clinically questionable. All patients were fasting during the magnetic resonance imaging (MRI) test to avoid nausea or dynamic contrast-enhanced vomiting from the contrast medium.

RESULT

In this study, we observed the form of the dynamic curve (time and signal intensity curve) type I (persistent curve) was noted in 12 lesions (37.5%): 10 lesions were benign and two lesions were malignant; type II (plateau curve) was noted in eight lesions (25%): three lesions were benign and five lesions were malignant, and type III (washout curve) noted in 12 lesions (37.5%): one lesion was benign and 11 lesions were malignant.

CONCLUSIONS

The dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) perfusion technique plays an important role in differentiating benign and malignant tumors in breast cancer.

Traditional cauterization among children in Bint Al-Huda Hospital in Al-Nasiriya City, Iraq

Cutaneous cautery is a form of traditional medicine practiced in many countries. It was mentioned in the books of many ancient, pre-, and post-Islamic scholars. Patients may resort to traditional medicine (cauterization in particular) for many reasons. This study aims is to acquire more knowledge about the cautery practices and the reasons for practicing cautery in children together with other implications from adverse events of the cautery. This is a cross-sectional study in which 133 children were enrolled (77 males and 56 females with age ranged from 0.5 to 108 months) who had been admitted to Bint Al-Huda Maternity and Childhood Teaching Hospital in Nasiriya city, Thi-Qar Governorate, Southern Iraq, from December 1, 2019 to end of July 2020). The study found that >80% of cauterized children were below 1 year, (53.4%) of rural residency. Parents of the cauterized children were mainly of illiterate and primary education constituting the highest percentage (91.6%) of cauterized children were of low per capita monthly income. The grandmothers were advisors in more than half of the cauterized children, a vast majority of the advisors were either illiterate or had primary education, The person performing the cautery was a traditional healer (95.5%). Cauterization was done mostly in the head and abdomen, and a vast majority of it was done by a lighted cotton-tipped application (97%). The number of cauterization points ranged from 2 to 25 with a mean of 8.8 cautery marks. Approximately 59% of patients did not improve or worsened, whereas 30% showed partial improvement, and 11% improved. Complications were seen in 9% of the cases. There is a necessity to spread awareness regarding the dangers and complications of traditional cauterization in health care centers by health care providers. Improving the delivery of medical services to areas far from the city centers as well as spreading health awareness by use of multimedia together with eradicating illiteracy is needed.

Evaluation of the outcomes of using iliac bone graft for reconstruction of traumatic orbital floor fractures

BACKGROUND

Orbital floor fracture is common in facial trauma patients. Although treated through surgical repair, the orbital floor fractures are associated with risk of persisting sensibility disorders, enophthalmos, and permanent diplopia due to complex anatomy of the orbit, time of surgery, and the reconstructive material used for such repairing.Failure of early recognition and treatment of these traumatic injuries may result in functional and cosmetic problems. Autogenous bone grafts are the gold standard for reconstruction of maxillofacial defects. The iliac crest is also considered the most ideal donor site for bone grafting when a large amount of bone is needed.

OBJECTIVE

To assess the outcome of early repair of orbital floor fractures regarding enophthalmos, double vision, extrusion, and gait disturbance.

PATIENTS AND METHODS

A total of 15 patients, all with orbital floor fracture, were enrolled, of which 12 of them were having pure blow-out fractures and 3 patients had impure blow-out fractures. All had undergone primary surgical reconstruction of the orbital floor by autogenous anterior iliac crest within 5-14 days of the injury.

RESULTS

The results were as follows: Postoperative complications at recipient site included diplopia (13.3%), enophthalmos (6.7%), and extrusion (6.7%). At the donor site, one patient had pain and the other had gait disturbances, both relieved within 1 month after treatment.

CONCLUSIONS

Less complications were reported postoperatively with the use of nonvascularized autogenous iliac bone graft.

Therapeutic Strategy of Mesenchymal-Stem-Cell-Derived Extracellular Vesicles as Regenerative Medicine

Extracellular vesicles (EVs) are lipid bilayer membrane particles that play critical roles in intracellular communication through EV-encapsulated informative content, including proteins, lipids, and nucleic acids. Mesenchymal stem cells (MSCs) are pluripotent stem cells with self-renewal ability derived from bone marrow, fat, umbilical cord, menstruation blood, pulp, etc., which they use to induce tissue regeneration by their direct recruitment into injured tissues, including the heart, liver, lung, kidney, etc., or secreting factors, such as vascular endothelial growth factor or insulin-like growth factor. Recently, MSC-derived EVs have been shown to have regenerative effects against various diseases, partially due to the post-transcriptional regulation of target genes by miRNAs. Furthermore, EVs have garnered attention as novel drug delivery systems, because they can specially encapsulate various target molecules. In this review, we summarize the regenerative effects and molecular mechanisms of MSC-derived EVs.

Exosomes derived from fibrinogen-like protein 1-overexpressing bone marrow-derived mesenchymal stem cells ameliorates rheumatoid arthritis

Rheumatoid arthritis (RA) is a most common chronic joint disease belonging to inflammatory autoimmune disease. The aim of this study was to determine the role and mechanism of bone marrow mesenchymal stem cells (BMSCs)-derived exosomes and fibrinogen-like protein 1 (FGL1) overexpression exosomes shuttled by BMSCs (FGL1-Exos) on RA. All of the exosomes were visualized by transmission electron microscope (TEM) and the characteristic proteins were detected by western blot. To investigate the therapeutic effect of FGL1-Exos, RA-FLSs were activated by TNF-α and RA rat model was established by collagen incomplete Freund's adjuvant. Cell viability, apoptosis, inflammation factors, and protein levels were detected by CCK-8, flow cytometry, enzyme-linked immunosorbent assay and western blot, respectively. Hematoxylin and eosin and safranin O staining were used to detect the histopathology changes. Cell apoptosis and FGL1 expression in knee joint were detected by immunofluorescence. The results showed that FGL1-Exos could inhibit the cell viability meanwhile increase the cell apoptosis in RA-FLSs. Meanwhile, FGL1-Exos could effectively suppress the inflammation score, joint destruction, and inflammatory response in RA rat model. FGL1-Exos directly inhibited cell apoptosis of RA-FLSs and RA rat model by suppressing the inflammatory cytokines, specific rheumatoid markers, immunological markers meanwhile meditating the NF-κB pathway. Our results indicate that FGL1 was a therapeutic potential target in RA therapy.