Regulatory T cells (Tregs) are the principal immune cells that exert anti-inflammatory effects within the organism. Their exosomes exhibit therapeutic efficacy across a broad spectrum of diseases owing to their high stability, low immunogenicity, and substantial penetration capacity. Recent research have indicated that isoallolithocholic acid (isoalloLCA), a metabolite associated with bile acid metabolism, may enhance Treg activity by upregulating forkhead box protein3 (Foxp3) expression. Hence, metabolite-based strategies for reinforcing Tregs may offer novel intervention options for treating related diseases. In this study, tumor necrosis factor (TNF)-α and dextran sulfate sodium (DSS) were employed to establish cellular and animal models of inflammatory bowel disease (IBD), further evaluating the therapeutic efficacy of isoalloLCA-intervened regulatory T cell exosomes (isoalloLCA-Exo) within this model. Our findings demonstrated that isoalloLCA-Exo effectively inhibit colitis progression in a murine model, as indicated by reduced inflammation, decreased apoptosis of intestinal epithelial cells, and improved intestinal barrier function. Furthermore, in vitro analyses elucidated the molecular mechanisms underlying the anti-inflammatory effects of isoalloLCA-Exo, revealing that the intervention effectively reversed TNF-α-induced inflammation and apoptosis in intestinal epithelial cells by modulating the NF-κB pathway. In conclusion, isoalloLCA-Exo can decelerate inflammatory bowel disease progression and suppress inflammatory response in intestinal epithelial cells by inhibiting NF-κB pathway. Notably, isoalloLCA-Exo exhibit superior efficacy to the traditional drug mesalazine and conventional treg exosome(NC-Exo). These findings have significant implications for optimizing Treg-derived exosome-based therapies for inflammation-related diseases.

Ulcerative colitis (UC) is characterized clinically by intestinal inflammation and gut microbiota dysbiosis. The consumption of biologics, although effective in inflammation control, may lead to adverse effects and is inconvenient for at-home administration. Goat milk-derived extracellular vesicles (GMEVs) have been proposed as a supplement to prevent intestinal inflammation. However, their therapeutic potential for colitis remains elusive. This study aimed to explore the preventive effect of GMEVs on colitis and its underlying mechanisms through the microbiota-immune axis using a dextran sodium sulfate (DSS)-induced colitis mouse model. We found that a pre-treatment of 20 mg/kg/d GMEVs effectively prevented body weight loss, colon shortening, the depletion of colonic goblet cells, and the disappearance of crypts, while enhancing the intestinal mucosal barrier. Consistent with these phenotypes, GMEV pre-treatment increased levels of IL-22 and IL-10 and decreased levels of IL-1β, TNF-α, IL-6, and iNOS. However, GMEVs themselves had no effect on normal mice. Paralleling the alleviation of intestinal inflammation, GMEV pre-treatment also restored the reduction in unclassified Muribaculaceae, Dubosiella, and Lactobacillus and suppressed the expansion of Alistipes and Proteobacteria following DSS treatment. Additionally, GMEV intake significantly downregulated the expression of proteins in the NF-κB signaling pathway induced by DSS. In summary, GMEVs could prevent colitis by regulating intestinal inflammation, the intestinal mucosal barrier, gut microbiota, organ damage, and the immune microenvironment. This study demonstrated that GMEVs have potential application prospects for UC prevention.

The field of extracellular vesicles (EVs) is advancing rapidly, and this review aims to synthesize the latest research connected to EVs and the gastrointestinal tract. We will address new and emerging roles for EVs derived from internal sources such as the pancreas and immune system and how these miniature messengers alter organismal health or the inflammatory response within the GI tract. We will examine what is known about external EVs from dietary and bacterial sources and the immense anti-inflammatory, immune-modulatory, and proliferative potential within these nano-sized information carriers. EV interactions with the intestinal and colonic epithelium and associated immune cells at homeostatic and disease states, such as necrotizing enterocolitis (NEC) and inflammatory bowel disease (IBD) will also be covered. We will discuss how EVs are being leveraged as therapeutics or for drug delivery and conclude with a series of unanswered questions in the field.

Extracellular vesicles (EVs) participate in intercellular communication and play an essential role in physiological and pathological processes. In recent years, EVs have garnered significant attention as cell-free therapeutic alternatives, vectors for drug and gene delivery, biomarkers for disease diagnosis and prognosis, vaccine development, and nutraceuticals. The biodistribution of EVs critically influences their efficacy and toxicity. Therefore, this review aims to discuss the main factors influencing the biodistribution of unmodified EVs, highlighting their distribution patterns, advantages, limitations, and applications under different routes of administration. In addition, we provide a comprehensive discussion of the currently available sources of EVs and summarize the current status of the therapeutic potentials of EVs. By optimizing administration routes and selecting appropriate EV sources, we aim to offer valuable insights to enhance the delivery efficiency and therapeutic efficacy of EVs to target tissues.

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs), especially, exosomes are considered to have diverse therapeutic effects for various significant diseases. MSC-derived exosomes (MSCex) offer substantial advantages over MSCs due to their long-term preservation, stability, absence of nuclei and fewer adverse effects such as infusion toxicity, thereby paving the way towards regenerative medicine and cell-free therapeutics. These exosomes harbor several cellular contents such as DNA, RNA, lipids, metabolites, and proteins, facilitating drug delivery and intercellular communication. MSCex have the ability to immunomodulate and trigger the anti-inflammatory process hence, playing a key role in alleviating inflammation and enhancing tissue regeneration. In this review, we addressed the anti-inflammatory effects of MSCex and the underlying immunomodulatory pathways. Moreover, we discussed the recent updates on MSCex in treating specific inflammatory diseases, including arthritis, inflammatory bowel disease, inflammatory eye diseases, and respiratory diseases such as asthma and acute respiratory distress syndrome (ARDS), as well as neurodegenerative and cardiac diseases. Finally, we highlighted the challenges in using MSCex as the successful therapeutic tool and discussed future perspectives.

Aim: Exosomes derived from adipose-derived stem cells (ASCs) in mice have been reported to influence immune regulation. Yet, the potential immunological effects of ASCs-derived exosomes and their interaction with lymphocytes during transplant immunity remain understudied. Methods: ASCs from BALB/c mice, along with their conditioned culture medium, were collected for the extraction, isolation, and comprehensive characterization of exosomes. Splenic cell suspensions were isolated from BALB/c mice and subsequently processed for downstream analyses. Lymphocytes were isolated via gradient centrifugation and stimulated in vitro with the purified exosomes to assess their functional responses. Lymphocyte proliferation was quantified using the CCK8 assay, and the relative frequencies of CD4+ T cells, CD8+ T cells, Treg cells, NK (natural killer) cells, macrophages, B cells, dendritic cells (DCs), and Th17 cells were determined through flow cytometric analysis. Before establishing the skin transplantation model, the mice were administered PBS, 0.5 × 108 exosomes, 1 × 108 exosomes, 1.5 × 108 exosomes, or ASCs via intravenous injection through the tail vein. Seven days after transplantation, the spleens, drainage lymph nodes, and blood samples were harvested for lymphocyte isolation and further downstream analyses. Results: Exosomes derived from ASCs significantly increased the CD4+/CD8+ ratio and Treg cell levels, without inducing any notable changes in Th17 cell content or CTLA-4 protein expression in CD4+ T cells. Compared to the PBS-treated group, both ASC and exosome treatment groups demonstrated an enhanced CD4+/CD8+ ratio, increased Treg cell content, and elevated CTLA-4 protein expression in spleen tissue following skin transplantation, while Th17 cell levels remained unaffected. Compared to the ASC treatment group, the exosome group exhibited a higher CD4+/CD8+ ratio and Treg cell levels, alongside a reduced proportion of PD-1+ Treg cells and lower CTLA-4 protein expression in CD3+CD4+ T cells. No significant differences were observed in the proportions of NK cells, macrophages, B cells, and DCs in the spleens across all treatment groups. In peripheral blood, an increased proportion of CD3+ T cells, macrophages, and DCs was detected, accompanied by a reduced proportion of NK cells and B cells. In the draining lymph nodes, no significant changes were observed in the proportions of CD3+ T cells and B cells, while macrophages, NK cells, and DCs showed elevated proportions. In the exosome-treated group, mouse grafts exhibited a disorganized and thinner granular layer, accompanied by focal regions of inflammatory cell infiltration. Both exosome and ASC treatments significantly extended the survival of skin grafts. Conclusion: Exosomes derived from ASCs promote lymphocyte proliferation and modulate their phenotypic profiles in mouse skin graft models, effectively extending graft survival.

Image 1.

Inflammatory bowel disease (IBD) is a persistent inflammation of the digestive system, and Mesenchymal Stem Cells (MSCs) and their exosomes have demonstrated potential as treatments for this condition. The objective of this research was to examine the possible effectiveness of intraperitoneal injection of umbilical cord-MSCs (UC-MSCs) and their exosomes through a two-time injection regimen in a mouse model.

In this study, an animal model of a specific type of IBD in C57BL/6 mice, induced by dextran sulfate sodium (DSS), was utilized. The mice were treated with MSCs, exosomes, Mesalazine, and a combination of them. Upon sacrificing the mice, colon and spleen tissues were isolated to assess the changes in the mice's weight, colon length, spleen weight, and colitis' pathological symptoms. IL-10 and IL-17 levels were measured, and Treg and Th17 cell percentages were determined as well. Furthermore, colon tissue was stained to investigate histopathological changes.

In the groups that received MSCs, there was a significant reduction in the disease activity index and their combinations with exosomes and Mesalazine compared to the colitis group. Colon length increased in all groups except the exosome group. Histological measures were notably reduced in the MSC groups and their combinations. Significant increases in the IL-10 level of colon tissue and the proportion of Treg present in the spleen were observed in the groups receiving MSC and combination treatment. Furthermore, these groups showed a notable reduction in the percentage of spleen Th17 cells. However, IL17A decreased non-significantly in all groups.

The results showed that intraperitoneal injection of UC-MSCs and their combination with exosome and Mesalazine in a murine colitis model improved the disease's symptoms. Therefore, MSCs and their combination with exosomes can be a promising therapeutic approach along with other common drugs for IBD, but exosomes alone could not significantly reduce the symptoms of colitis.

As functional derivatives of mesenchymal stem cells (MSCs), small extracellular vesicles (sEVs) have garnered significant attention and application in regenerative medicine. However, the technical limitations for large-scale isolation of sEVs and their heterogeneous nature have added complexity to their applications. It remains unclear if the heterogeneous sEVs represent different aspects of MSCs functions. Here, we provide a method for the large-scale production of sEVs subpopulations derived from human umbilical cord mesenchymal stem cells (HucMSCs), utilizing tangential flow filtration combined with size exclusion chromatography. The resulting subpopulations, S1-sEVs and S2-sEVs, exhibited stable variations in size, membrane-marked proteins, and carrying cargos, thereby displaying distinct functions both in vitro and in animal disease models. S1-sEVs, that highly expressed CD9, HRS and GPC1, demonstrated a greater immunomodulatory impact, while S2-sEVs with enriched expression of CD63 and FLOT1/2 possessed enhanced capacities in promoting cell proliferation and angiogenesis. These discrepancies are attributed to the specific proteins and miRNAs they contain. Further investigation revealed that the two distinct sEVs subpopulations corresponded to different biological processes: the ESCRT pathway (S1-sEVs) and the ESCRT-independent pathway represented by lipid rafts (S2-sEVs). Therefore, we propose the potential for large-scale isolation and purification of sEVs subpopulations from HucMSCs with distinct functions. This approach may provide advantages for targeted therapeutic interventions in various MSC indications.

The multi-biological barriers present in the inflammatory microenvironment severely limit the targeted aggregation of anti-inflammatory drugs in the lesion area. However, conventional responsive drug carriers inevitably come into contact with several pro-responsive stimulatory mediators simultaneously, leading to premature drug release and loss of most therapeutic effects. Breaking through the multi-level barriers of the inflammatory microenvironment is essential to improve the enrichment and bioavailability of drugs.

In this study, we propose a novel two-stage structural strategy to build shielded cascades of targeted nanocarriers (FA-PTP@Que) through inflammatory mediators, using cascade structures to cross multiple environmental barriers. The cascade structure of FA-PTP@Que is responsive to inflammatory mediators and exhibits ideal pathological microenvironmental response and drug release properties. FA-PTP@Que has shown good macrophage regulation and anti-inflammatory effects by efficiently targeting macrophages, scavenging intracellular reactive oxygen species (ROS), and down-regulating the secretion of pro-inflammatory factors. Significantly, in mice with arthritis and colitis, FA-PTP@Que enriches and targets macrophages at the sites of arthritis and colitis, showing significant anti-inflammatory effects.

FA-PTP@Que combines active chemotaxis of nanocarriers to inflammatory tissues and active targeting of effector cells, acting precisely at each barrier level in different microenvironments by responding to inflammatory mediators and overcoming the multiple barriers in the inflammatory microenvironment. This innovative strategy can effectively break through various inflammatory microenvironments and has the potential application to other inflammatory diseases.

The global increase in the aging population has led to a concurrent rise in the incidence of age-related diseases, posing substantial challenges to healthcare systems and affecting the well-being of the elderly. Identifying and securing effective treatments has become an urgent priority. In this context, mesenchymal stem cell-derived exosomes (MSC-Exos) have emerged as a promising and innovative modality in the field of anti-aging medicine, offering a multifaceted therapeutic approach. MSC-Exos demonstrate significant potential due to their immunomodulatory and anti-inflammatory properties, their ability to inhibit oxidative stress, and their reparative effects on senescent tissues. These attributes make them valuable in combating a range of conditions associated with aging, such as cardiovascular diseases, neurodegeneration, skin aging, and osteoarthritis. The integration of exosomes with membrane-penetrating peptides introduces a novel strategy for the delivery of biomolecules, surmounting traditional cellular barriers and enhancing therapeutic efficacy. This review provides a comprehensive synthesis of the current understanding of MSC-Exos, underscoring their role as a novel and potent therapeutic strategy against the intricate challenges of age-related diseases.

Exosomes, nano-sized lipid bilayer vesicles, have garnered significant attention as mediators of cell communication, particularly within the central nervous system (CNS). Their unique properties, including high stability, low immunogenicity, and the ability to traverse the blood-brain barrier (BBB), position them as promising tools for understanding and addressing CNS diseases. This comprehensive review delves into the biogenesis, properties, composition, functions, and isolation of exosomes, with a particular focus on their roles in cerebrovascular diseases, neurodegenerative disorders, and CNS tumors. Exosomes are involved in key pathophysiological processes in the CNS, including angiogenesis, inflammation, apoptosis, and cellular microenvironment modification. They demonstrate promise in mitigating ischemic injury, regulating inflammatory responses, and providing neuroprotection across various CNS conditions. Furthermore, exosomes carry distinct biomolecules, offering a novel method for the early diagnosis and monitoring of CNS diseases. Despite their potential, challenges such as complex extraction processes, the heterogeneity of exosomal contents, and targeted delivery limitations hinder their clinical application. Nevertheless, exosomes hold significant promise for advancing our understanding of CNS diseases and developing novel therapeutic strategies. This manuscript significantly contributes to the field by highlighting exosomes' potential in advancing our understanding of CNS diseases, underscoring their unique value in developing novel therapeutic strategies and mediating cellular communication.

Sepsis is a life-threatening disease caused by the overwhelming response to pathogen infections. Currently, treatment options for sepsis are limited to broad-spectrum antibiotics and supportive care. However, the growing resistance of pathogens to common antibiotics complicates treatment efforts. Excessive immune response (i.e., cytokine storm) can persist even after the infection is cleared. This overactive inflammatory response can severely damage multiple organ systems. Given these challenges, managing the excessive immune response is critical in controlling sepsis progression. Therefore, Mesenchymal stem cells (MSCs), with their immunomodulatory and antibacterial properties, have emerged as a promising option for adjunctive therapy in treating sepsis. Moreover, MSCs exhibit a favorable safety profile, as they are eventually eliminated by the host's immune system within several months post-administration, resulting in minimal side effects and have not been linked to common antibiotic therapy drawbacks (i.e., antibiotic resistance). This review explores the potential of MSCs as a personalized therapy for sepsis treatment, clarifying their mechanisms of action and providing up-to-date technological advancements to enhance their protective efficacy for patients suffering from sepsis and its consequences.

IBD, an autoimmune-inflammatory disorder that affects people who are genetically prone to inflammation. There is a lot of interest in MSC-CM therapy, especially when primed with TNF-α + IFN-γ. Throughout the study, data were collected on the percentage of apoptotic cells, gene expression of ZO-1, Foxp3, GATA3, IDO-1, Muc2, T-bet, Notch1, TNFR2, and ROR-γt, colon weight and length, histopathological analysis, and DAI. TNF-α and IL-10 levels were assessed in addition to the NO level. The results suggest that primed MSC-CM improved DAI, mucosal deterioration, intestinal inflammation and NO concentration. The amount of TNF-α was decreased, but IL-10 and the colon's percentage of apoptotic cells was increased. The mRNA expression of ZO-1, Foxp3, GATA3, IDO-1, and Muc2 genes increased greatly in the treatment groups, while the expression of T-bet, Notch1, TNFR2, and ROR-γt genes has decreased. These studies suggest that primed MSC-CM may combine with common treatments to improve responsiveness.

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as key regulators of intercellular communication, orchestrating essential biological processes by delivering bioactive cargoes to target cells. Available evidence suggests that MSC-EVs can mimic the functions of their parental cells, exhibiting immunomodulatory, pro-regenerative, anti-apoptotic, and antifibrotic properties. Consequently, MSC-EVs represent a cell-free therapeutic option for patients with inflammatory bowel disease (IBD), overcoming the limitations associated with cell replacement therapy, including their non-immunogenic nature, lower risk of tumourigenicity, cargo specificity and ease of manipulation and storage.

This review aims to provide a comprehensive examination of the therapeutic efficacy of MSC-EVs in IBD, with a focus on their mechanisms of action and potential impact on treatment outcomes. We examine the advantages of MSC-EVs over traditional therapies, discuss methods for their isolation and characterisation, and present mechanistic insights into their therapeutic effects through transcriptomic, proteomic and lipidomic analyses of MSC-EV cargoes. We also discuss available preclinical studies demonstrating that MSC-EVs reduce inflammation, promote tissue repair and restore intestinal homeostasis in IBD models, and compare these findings with those of clinical trials.

Finally, we highlight the potential of MSC-EVs as a novel therapy for IBD and identify challenges and opportunities associated with their translation into clinical practice.

The source of mesenchymal stem cells (MSCs) strongly influences the composition and function of MSC-derived extracellular vesicles (EVs), affecting their therapeutic potential. Adipose-derived MSC-EVs, known for their immunoregulatory properties and ease of isolation, show promise as a treatment for inflammatory bowel disease (IBD). MicroRNAs are consistently present in MSC-EVs across cell types and are involved in pathways that are dysregulated in IBD, making them potential therapeutic agents. For example, miR-let-7a is associated with inhibition of apoptosis, miR-100 supports cell survival, miR-125b helps suppress pro-inflammatory cytokines and miR-20 promotes anti-inflammatory M2 macrophage polarisation. Preclinical studies in IBD models have shown that MSC-EVs reduce intestinal inflammation by suppressing pro-inflammatory mediators (e.g., TNF-α, IL-1β, IL-6) and increasing anti-inflammatory factors (e.g., IL-4, IL-10). They also promote mucosal healing and strengthen the integrity of the gut barrier, suggesting their potential to address IBD pathology.

This chapter presents an overview of the emerging strategies to address the unmet needs in the management of inflammatory bowel diseases (IBD). IBD poses significant challenges, as over half of patients experience disease progression despite interventions, leading to irreversible complications, and a substantial proportion do not respond to existing therapies, such as biologics. To overcome these limitations, we describe a diverse array of novel therapeutic approaches. In the area of immune homeostasis restoration, the focus is on targeting cytokine networks, leukocyte trafficking, novel immune pathways, and cell therapies involving regulatory T cells and mesenchymal stem cells (MSC). Recognizing the critical role of impaired intestinal barrier integrity in IBD, we highlight therapies aimed at restoring barrier function and promoting mucosal healing, such as those targeting cell proliferation, tight junctions, and lipid mediators. Addressing the challenges posed by fibrosis and fistulas, we describe emerging targets for reversing fibrosis like kinase and cytokine inhibitors and nuclear receptor agonists, as well as the potential of MSC for fistulas. The restoration of a healthy gut microbiome, through strategies like fecal microbiota transplantation, rationally defined bacterial consortia, and targeted antimicrobials, is also highlighted. We also describe innovative approaches to gut-targeted drug delivery to enhance efficacy and minimize side effects. Reinforcing these advancements is the critical role of precision medicine, which emphasizes the use of multiomics analysis for the discovery of biomarkers to enable personalized IBD care. Overall, the emerging landscape of therapeutic opportunities for IBD holds great potential to surpass the therapeutic ceiling of current treatments.

Autoimmune hepatitis (AIH) is an immune-mediated liver disease that currently faces limited treatment options. In its advanced stages, AIH can progress to liver fibrosis and cirrhosis. Recent research has increasingly focused on cell-free therapies, particularly the use of mesenchymal stem cell (MSC)-derived exosomes (Exos), which have shown promise in treating autoimmune diseases, including AIH. MSC-Exos, as microvesicles with low immunogenicity, high safety, and permeability, can deliver RNA, DNA, proteins, lipids, and various drugs for disease treatment, showing promising clinical application prospects. This review provides a comprehensive summary of the current research on MSC-Exos in the treatment of autoimmune hepatitis (AIH) and explores the underlying molecular mechanisms involved. It highlights the significant regulatory effects of MSC-Exos on immune cells and their ability to modify the microenvironment, demonstrating anti-inflammatory and anti-fibrotic properties while promoting liver regeneration. Additionally, this review also discusses potential challenges and future strategies for advancing Exo-based therapies in the treatment of AIH.

Plant-derived extracellular vesicles (EVs) are promising therapeutic agents owing to their natural abundance, accessibility, and unique biological properties. This review provides a comprehensive exploration of the therapeutic potential of plant-derived EVs and emphasizes their anti-inflammatory, antimicrobial, and tumor-inhibitory effects. Here, we discussed the advancements in isolation and purification techniques, such as ultracentrifugation and size-exclusion chromatography, which are critical for maintaining the functional integrity of these nanovesicles. Next, we investigated the diverse administration routes of EVs and carefully weighed their respective advantages and challenges related to bioavailability and patient compliance. Moreover, we elucidated the multifaceted mechanisms of action of plant-derived EVs, including their roles in anti-inflammation, antioxidation, antitumor activity, and modulation of gut microbiota. We also discussed the impact of EVs on specific diseases such as cancer and inflammatory bowel disease, highlighting the importance of addressing current challenges related to production scalability, regulatory compliance, and immunogenicity. Finally, we proposed future research directions for optimizing EV extraction and developing targeted delivery systems. Through these efforts, we envision the seamless integration of plant-derived EVs into mainstream medicine, offering safe and potent therapeutic alternatives across various medical disciplines.

Mesenchymal stem cells (MSCs) are pluripotent stem cells derived from mesoderm. Through cell-to-cell contact or paracrine effects, they carry out biological tasks like immunomodulatory, anti-inflammatory, regeneration, and repair. Extracellular vesicles (EVs) are the primary mechanism for the paracrine regulation of MSCs. They deliver proteins, nucleic acids, lipids, and other active compounds to various tissues and organs, thus facilitating intercellular communication. Rheumatic diseases may be treated using MSCs and MSC-derived EVs (MSC-EVs) due to their immunomodulatory capabilities, according to mounting data. Since MSC-EVs have low immunogenicity, high stability, and similar biological effects as to MSCs themselves, they are advantageous over cell therapy for potential therapeutic applications in rheumatoid arthritis, systemic erythematosus lupus, systemic sclerosis, Sjogren's syndrome, and other rheumatoid diseases. This review integrates recent advances in the characteristics, functions, and potential molecular mechanisms of MSC-EVs in rheumatic diseases and provides a new understanding of the pathogenesis of rheumatic diseases and MSC-EV-based treatment strategies.

We and other groups have documented that bone marrow-mesenchymal stem cells (BM-MSCs) from Systemic lupus erythematosus (SLE) patients demonstrated signs of senescence, including reduced ability of regulating Treg. Treg cell defects or Treg cell deficiency are regarded as significant factors in the progression of SLE. Exosomes, nanoscale vesicles, abound in molecular and genetic contents, play a critical role in intercellular communications. The purpose of this research is to investigate the mechanism of MSCs-exosomes regulating Tregs cells in SLE, further elucidate the mechanism of immune dysregulation of aging BM-MSCs, and provide theoretical basis and data support for new targets of SLE treatment. In the study, BM-MSCs and exosomes were isolated successfully. Exosomes could be up-taken by naïve CD4+T cells. MSCs-exosomes attenuated SLE clinical manifestation in vivo, but MSCs-exosomes from SLE patients were ineffective. MSCs-exosomes from SLE patients dysregulated Treg cells differentiation in vivo and in vitro. Exosomal miR-20a-5p contributed to the effect of MSCs-exosomes regulating Treg cells. Up-regulating the expression of miR-20a-5p in SLE MSCs-exosomes can restore their ability to promote Treg differentiation and treatment effect. This study further elucidated the role of in the immunomodulatory mechanism of BM-MSCs-exosomes and provided new ideas for the non-cellular autologous transplantation therapy of SLE.

Extracellular vesicles (EVs) are being considered as a potential therapeutic option for ulcerative colitis (UC), and numerous preclinical studies have been conducted on the use of EVs for UC.

A systematic review was conducted to compare the therapeutic effects of mammalian EVs and placebo on UC in animal models, along with a meta-analysis comparing naïve (unmodified) EVs and placebo. The search was performed in four databases (PubMed, Web of Science, Scopus, and EMBASE) up to September 13th, 2023. The primary outcomes included disease activity index (DAI), colonic mucosal damage index (CMDI), and adverse effects (PROSPERO ID: CRD42023458039).

A total of 69 studies were included based on pre-determined criteria, involving 1271 animals. Of these studies, 51 measured DAI scores, with 98 % reporting that EVs could reduce DAI scores. Additionally, 5 studies reported CMDI and all showed that EVs could significantly reduce CMDI. However, only 3 studies assessed adverse effects and none reported any significant adverse effects. The meta-analysis of these studies (40 studies involving 1065 animals) revealed that naïve EVs could significantly decrease the DAI score (SMD = -3.00; 95 % CI: -3.52 to -2.48) and CMDI (SMD = -2.10; 95 % CI: -2.85 to -1.35).

The results indicate that mammalian EVs have demonstrated therapeutic benefits in animal models of UC; however, the safety profile of EVs remains inadequate which highlights the need for further research on safety outcomes.

Inflammatory bowel disease (IBD) is a complex and recurring inflammatory disorder that affects the gastrointestinal tract and is influenced by genetic predisposition, immune dysregulation, the gut microbiota, and environmental factors. Advanced therapies, such as biologics and small molecules, target diverse immune pathways to manage IBD. Nanoparticle (NP)-based drugs have emerged as effective tools, offering controlled drug release and targeted delivery. This review highlights NP modifications for anti-inflammatory purposes, utilizing changes such as those in size, charge, redox reactions, and ligand-receptor interactions in drug delivery systems. By using pathological and microenvironmental cues to guide NP design, precise targeting can be achieved. In IBD, a crucial aspect of NP intervention is targeting specific types of cells, such as immune and epithelial cells, to address compromised intestinal barrier function and reduce overactive immune responses. This review also addresses current challenges and future prospects, with the goal of advancing the development of NP-mediated strategies for IBD treatment.

In the fields of tissue engineering and regenerative medicine, extracellular vesicles (EVs) have become viable therapeutic tools. EVs produced from stem cells promote tissue healing by regulating the immune system, enhancing cell proliferation and aiding remodeling processes. Recently, EV has gained significant attention from researchers due to its ability to treat various diseases. Unlike stem cells, stem cell-derived EVs show lower immunogenicity, are less able to overcome biological barriers, and have a higher safety profile. This makes the use of EVs derived from cell-free stem cells a promising alternative to whole-cell therapy. This review focuses on the biogenesis, isolation, and characterization of EVs and highlights their therapeutic potential for bone fracture healing, wound healing, and neuronal tissue repair and treatment of kidney and intestinal diseases. Additionally, this review discusses the potential of EVs for the treatment of cancer, COVID-19, and HIV. In summary, the use of EVs derived from stem cells offers a new horizon for applications in tissue engineering and regenerative medicine.

The chronic immune-mediated inflammatory condition known as inflammatory bowel disease (IBD) significantly affects the gastrointestinal system. While the precise etiology of IBD remains elusive, extensive research suggests that a range of pathophysiological pathways and immunopathological mechanisms may significantly contribute as potential factors. Mesenchymal stem cells (MSCs) have shown significant potential in the development of novel therapeutic approaches for various medical conditions. However, some MSCs have been found to exhibit tumorigenic characteristics, which limit their potential for medical treatments. The extracellular vesicles (EVs), paracrine factors play a crucial role in the therapeutic benefits conferred by MSCs. The EVs consist of proteins, microRNAs, and lipids, and are instrumental in facilitating intercellular communication. Due to the ease of maintenance, and decreased immunogenicity, tumorigenicity the EVs have become a new and exciting option for whole cell treatment. This review comprehensively assesses recent preclinical research on human umbilical cord mesenchymal stem cell (hUC-MSC)-derived EVs as a potential IBD therapy. It comprehensively addresses key aspects of various conditions, including diabetes, cancer, dermal injuries, neurological disorders, cardiovascular issues, liver and kidney diseases, and bone-related afflictions.

Allergic rhinitis (AR) is an upper airway inflammatory disease of the nasal mucosa. Conventional treatments such as symptomatic pharmacotherapy and allergen-specific immunotherapy have considerable limitations and drawbacks. As an emerging therapy with regenerative potential and immunomodulatory effect, mesenchymal stem cell-derived exosomes (MSC-Exos) have recently been trialed for the treatment of various inflammatory and autoimmune diseases.

In order to achieve sustained and protected release of MSC-Exos for intranasal administration, we fabricated Poly(lactic-co-glycolic acid) (PLGA) micro and nanoparticles-encapsulated MSC-Exos (PLGA-Exos) using mechanical double emulsion for local treatment of AR. Preclinical in vivo imaging, ELISA, qPCR, flow cytometry, immunohistochemical staining, and multiomics sequencing were used for phenotypic and mechanistic evaluation of the therapeutic effect of PLGA-Exos in vitro and in vivo.

The results showed that our PLGA platform could efficiently encapsulate and release the exosomes in a sustained manner. At protein level, PLGA-Exos treatment upregulated IL-2, IL-10 and IFN-γ, and downregulated IL-4, IL-17 and antigen-specific IgE in ovalbumin (OVA)-induced AR mice. At cellular level, exosomes treatment reduced Th2 cells, increased Tregs, and reestablished Th1/Th2 balance. At tissue level, PLGA-Exos significantly attenuated the infiltration of immune cells (e.g., eosinophils and goblet cells) in nasal mucosa. Finally, multiomics analysis discovered several signaling cascades, e.g., peroxisome proliferator-activated receptor (PPAR) pathway and glycolysis pathway, that might mechanistically support the immunomodulatory effect of PLGA-Exos.

For the first time, we present a biomaterial-facilitated local delivery system for stem cell-derived exosomes as a novel and promising strategy for AR treatment.

Bone marrow-derived mesenchymal stem cell (BMMSC)-based therapy has become a major focus for treating liver fibrosis/cirrhosis. However, although these cell therapies promote the treatment of this disease, the heterogeneity of BMMSCs, which causes insufficient efficacy during clinical trials, has not been addressed. In this study, we describe a novel Percoll-Plate-Wait procedure (PPWP) for the isolation of an active cell subset from BMMSC cultures that was characterized by the expression of neuroglial antigen 2 (NG2/BMMSCs).

By using the key method of PPWP and other classical biological techniques we compared NG2/BMMSCs with parental BMMSCs in biological and functional characteristics within a well-defined diethylnitrosamine (DEN)-induced liver fibrosis/cirrhosis injury male C57BL/6 mouse model also in a culture system. Of note, the pathological alterations in the model is quite similar to humans'.

The NG2/BMMSCs revealed more advantages compared to parentalBMMSCs. They exhibited greater proliferation potential than parental BMMSCs, as indicated by Ki-67 immunofluorescence (IF) staining. Moreover, higher expression of SSEA-3 (a marker specific for embryonic stem cells) was detected in NG2/BMMSCs than in parental BMMSCs, which suggested that the "stemness" of NG2/BMMSCs was greater than that of parental BMMSCs. In vivo studies revealed that an injection of NG2/BMMSCs into mice with ongoing DEN-induced liver fibrotic/cirrhotic injury enhanced repair and functional recovery to a greater extent than in mice treated with parental BMMSCs. These effects were associated with the ability of NG2/BMMSCs to differentiate into bile duct cells (BDCs). In particular, we discovered for the first time that NG2/BMMSCs exhibit unique characteristics that differ from those of parental BMMSCs in terms of producing liver sinusoidal endothelial cells (LSECs) to reconstruct injured blood vessels and sinusoidal structures in the diseased livers, which are important for initiating hepatocyte regeneration. This unique potential may also suggest that NG2/BMMSCs could be an novel off-liver progenitor of LSECs. Ex vivo studies revealed that the NG2/BMMSCs exhibited a similar trend to that of their in vivo in terms of functional differentiation responding to the DEN-diseased injured liver cues. Additionally, the obvious core role of NG2/BMMSCs in supporting the functions of BMMSCs in bile duct repair and BDC-mediated hepatocyte regeneration might also be a novel finding.

Overall, the PPWP-isolated NG2/BMMSCs could be a novel effective cell subset with increased purity to serve as a new therapeutic tool for enhancing treatment efficacy of BMMSCs and special seed cell source (BDCs, LSECs) also for bioliver engineering.

Inflammatory bowel disease (IBD) poses a significant challenge in modern medicine, with conventional treatments limited by efficacy and associated side effects, necessitating innovative therapeutic approaches. Mesenchymal stem cells (MSC) have emerged as promising candidates for IBD treatment due to their immunomodulatory properties and regenerative potential. This thesis aims to explore and compare various sources of MSC and evaluate their efficacy in treating IBD. This study comprehensively analyses MSC derived from multiple sources, including bone marrow, adipose tissue, umbilical cord, and other potential reservoirs. Core elements of this investigation include assessing differences in cell acquisition, immunomodulatory effects, and differentiation capabilities among these MSC sources, as well as comparing their clinical trial outcomes in IBD patients to their therapeutic efficacy in animal models. Through meticulous evaluation and comparative analysis, this thesis aims to elucidate disparities in the efficacy of different MSC sources for IBD treatment, thereby identifying the most promising therapeutic applications. The findings of this study are intended to advance our understanding of MSC biology and offer valuable insights for selecting the most effective MSC sources for personalized IBD therapy. Ultimately, this research endeavor will optimise therapeutic strategies for managing inflammatory bowel disease through the utilization of MSC.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract, which has a high recurrence rate and is incurable due to a lack of effective treatment. Mesenchymal stromal cells (MSCs) are a class of pluripotent stem cells that have recently received a lot of attention due to their strong self-renewal ability and immunomodulatory effects, and a large number of experimental and clinical models have confirmed the positive therapeutic effect of MSCs on IBD. In preclinical studies, MSC treatment for IBD relies on MSCs paracrine effects, cell-to-cell contact, and its mediated mitochondrial transfer for immune regulation. It also plays a therapeutic role in restoring the intestinal mucosal barrier through the homing effect, regulation of the intestinal microbiome, and repair of intestinal epithelial cells. In the latest clinical trials, the safety and efficacy of MSCs in the treatment of IBD have been confirmed by transfusion of autologous or allogeneic bone marrow, umbilical cord, and adipose MSCs, as well as their derived extracellular vesicles. However, regarding the stable and effective clinical use of MSCs, several concerns emerge, including the cell sources, clinical management (dose, route and frequency of administration, and pretreatment of MSCs) and adverse reactions. This article comprehensively summarizes the effects and mechanisms of MSCs in the treatment of IBD and its advantages over conventional drugs, as well as the latest clinical trial progress of MSCs in the treatment of IBD. The current challenges and future directions are also discussed. This review would add knowledge into the understanding of IBD treatment by applying MSCs.

Mesenchymal stem cells (MSCs) have shown great potential in the treatment of several inflammatory diseases due to their immunomodulatory ability, which is mediated by exosomes secreted by MSCs (MSC-Exs). The incidence of inflammatory bowel disease (IBD) is increasing globally, but there is currently no long-term effective treatment. As an emerging therapy, MSC-Exs have proven to be effective in alleviating IBD experimentally, and the specific mechanism continues to be explored. The gut microbiota plays an important role in the occurrence and development of IBD, and MSCs and MSC-Exs can effectively regulate gut microbiota in animal models of IBD, but the mechanism involved and whether the outcome can relieve the characteristic dysbiosis necessary to alleviate IBD still needs to be studied. This review provides current evidence on the effective modulation of the gut microbiota by MSC-Exs, offering a basis for further research on the pathogenic mechanism of IBD and MSC-Ex treatments through the improvement of gut microbiota.

This study aimed to examine the effects of the secretome released by human umbilical cord-mesenchymal stem cells (MSC) as a result of preconditioning with deferoxamine (DFX), a hypoxia mimetic agent, on type 1 diabetes (T1D), by comparing it with the secretome produced by untreated MSCs. Initially, the levels of total protein, IL4, IL10, IL17, and IFNγ in the conditioned medium (CM) obtained from MSCs subjected to preconditioning with 150 µM DFX (DFX-CM) were analyzed in comparison to CM derived from untreated MSCs (N-CM). Subsequently, the CMs were administered to rats with T1D within a specific treatment plan. Following the sacrification, immunomodulation was evaluated by measuring serum cytokine levels and assessing the regulatory T cell (Treg) ratio in spleen mononuclear cells. Additionally, β-cell mass was determined in the islets by immunohistochemical labeling of NK6 Homeobox 1 (Nkx6.1), Pancreatic duodenal homeobox-1 (Pdx1), and insulin antibodies in pancreatic sections. In vitro findings indicated that the secretome levels of MSCs were enhanced by preconditioning with DFX. In vivo, the use of DFX-CM significantly increased the Treg population, and accordingly, the level of inflammatory cytokines decreased. In β-cell marker labeling, D + DFX-CM showed significantly increased PDX1 and insulin immunoreactivity. In conclusion, while the factors released by MSCs without external stimulation had limited therapeutic effects, substantial improvements in immunomodulation and β-cell regeneration were seen with DFX-preconditioned cell-derived CM.

Neonatal disorders, particularly those resulting from prematurity, pose a major challenge in health care and have a significant impact on infant mortality and long-term child health. The limitations of current therapeutic strategies emphasize the need for innovative treatments. New cell-free technologies utilizing extracellular vesicles (EVs) offer a compelling opportunity for neonatal therapy by harnessing the inherent regenerative capabilities of EVs. These nanoscale particles, secreted by a variety of organisms including animals, bacteria, fungi and plants, contain a repertoire of bioactive molecules with therapeutic potential. This review aims to provide a comprehensive assessment of the therapeutic effects of EVs and mechanistic insights into EVs from stem cells, biological fluids and non-animal sources, with a focus on common neonatal conditions such as hypoxic-ischemic encephalopathy, respiratory distress syndrome, bronchopulmonary dysplasia and necrotizing enterocolitis. This review summarizes evidence for the therapeutic potential of EVs, analyzes evidence of their mechanisms of action and discusses the challenges associated with the implementation of EV-based therapies in neonatal clinical practice.

Ulcerative colitis (UC) is a chronic recurrent inflammatory bowel disease. Despite ongoing advances in our understanding of UC, its pathogenesis is yet unelucidated, underscoring the urgent need for novel treatment strategies for patients with UC. Exosomes are nanoscale membrane particles that mediate intercellular communication by carrying various bioactive molecules, such as proteins, RNAs, DNA, and metabolites. The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is a cytosolic tripartite protein complex whose activation induces the maturation and secretion of proinflammatory cytokines interleukin-1β (IL-1β) and IL-18, triggering the inflammatory response to a pathogenic agent or injury. Growing evidence suggests that exosomes are new modulators of the NLRP3 inflammasome, with vital roles in the pathological process of UC. Here, recent evidence is reviewed on the role of exosomes and NLRP3 inflammasome in UC. First, the dual role of exosomes on NLRP3 inflammasome and the effect of NLRP3 inflammasome on exosome secretion are summarized. Finally, an outlook on the directions of exosome-NLRP3 inflammasome crosstalk research in the context of UC is proposed and areas of further research on this topic are highlighted.

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.

Circular RNAs (circRNAs) are highly expressed in the mammalian intestinal epithelium, but their functions remain largely unknown. Here, we identified the circRNA Cdr1as as a repressor of intestinal epithelial regeneration and defense. Cdr1as levels increased in mouse intestinal mucosa after colitis and septic stress, as well as in human intestinal mucosa from patients with inflammatory bowel disease and sepsis. Ablation of the Cdr1as locus from the mouse genome enhanced renewal of the intestinal mucosa, promoted injury-induced epithelial regeneration, and protected the mucosa against colitis. We found approximately 40 microRNAs, including miR-195, differentially expressed between intestinal mucosa of Cdr1as-knockout (Cdr1as-/-) versus littermate mice. Increasing the levels of Cdr1as inhibited intestinal epithelial repair after wounding in cultured cells and repressed growth of intestinal organoids cultured ex vivo, but this inhibition was abolished by miR-195 silencing. The reduction in miR-195 levels in the Cdr1as-/- intestinal epithelium was the result of reduced stability and processing of the precursor miR-195. These findings indicate that Cdr1as reduces proliferation and repair of the intestinal epithelium at least in part via interaction with miR-195 and highlight a role for induced Cdr1as in the pathogenesis of unhealed wounds and disrupted renewal of the intestinal mucosa.

The treatment landscape for inflammatory bowel disease (IBD) has undergone substantial advancements with the introduction of biologics. However, a considerable number of patients either show an immediate lack of response or lose responsiveness over time, necessitating the development of innovative and effective treatment approaches. Extracellular vesicles (EVs) are small lipid bilayer-enclosed structures that facilitate cell-to-cell molecular transfer and are integral to the pathogenesis of IBD. They play pivotal roles in maintaining the integrity of the intestinal epithelial barrier and the expulsion of cellular metabolites. The potential use of EVs as drug carriers or therapeutic agents has opened up a plethora of clinical applications. This review investigates the creation and content of EVs, their role in IBD development, and advances in their isolation and analytical techniques. Furthermore, the therapeutic promise they hold for IBD is explored, along with the latest research on their roles as IBD drug delivery systems.

Extracellular vesicles are nanoscale vesicles that can be secreted by all cell types, are intracellular in origin and have the same composition as their parent cells, play a key role in intercellular communication in organismal health and disease, and are now often used as biomarkers of disease and therapeutic agents in biomedical research. When injected locally or systemically, they have the ability to provide a variety of therapeutic effects, for example, regeneration of skin damage or restoration of cardiac function. However, direct injection of extracellular vesicles may result in their rapid clearance from the injection site.In order to maintain the biological activity of extracellular vesicles and to control the release of effective concentrations for better therapeutic efficacy during long-term disease treatment, the design of an optimized drug delivery system is necessary and different systems for the continuous delivery of extracellular vesicles have been developed. This paper first provides an overview of the biogenesis, composition and physiological function of extracellular vesicles, followed by a review of different strategies for extracellular vesicle isolation and methods for engineering extracellular vesicles. In addition, this paper reviews the latest extracellular vesicle delivery platforms such as micro-nanoparticles, injectable hydrogels, microneedles and scaffold patches. At the same time, the research progress and key cases of extracellular vesicle delivery systems in the field of biomedical therapeutics are described. Finally, the challenges and future trends of extracellular vesicle delivery are discussed.