Dosing extracellular vesicles

The role of oxidative stress in intervertebral disc degeneration: Mechanisms and therapeutic implications

Oxidative stress is one of the main driving mechanisms of intervertebral disc degeneration(IDD). Oxidative stress has been associated with inflammation in the intervertebral disc, cellular senescence, autophagy, and epigenetics of intervertebral disc cells. It and the above pathological mechanisms are closely linked through the common hub reactive oxygen species(ROS), and promote each other in the process of disc degeneration and promote the development of the disease. This reveals the important role of oxidative stress in the process of IDD, and the importance and great potential of IDD therapy targeting oxidative stress. The efficacy of traditional therapy is unstable or cannot be maintained. In recent years, due to the rise of materials science, many bioactive functional materials have been applied in the treatment of IDD, and through the combination with traditional drugs, satisfactory efficacy has been achieved. At present, the research review of antioxidant bioactive materials in the treatment of IDD is not complete. Based on the existing studies, the mechanism of oxidative stress in IDD and the common antioxidant therapy were summarized in this paper, and the strategies based on emerging bioactive materials were reviewed.

Effects of extracellular vesicles for ischemic stroke: A meta‑analysis of preclinical studies

Ischemic stroke is a common occurrence worldwide, posing a severe threat to human health and leading to negative financial impacts. Currently available treatments still have numerous limitations. As research progresses, extracellular vesicles are being found to have therapeutic potential in ischemic stroke. In the present study, the literature on extracellular vesicle therapy in animal studies of ischemic stroke was screened by searching databases, including PubMed, Embase, Medline, Web of Science and the Cochrane Library. The main outcomes of the present study were the neurological function score, apoptotic rate and infarct volumes. The secondary outcomes were pro-inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. The study quality was assessed using the CAMARADES Checklist. Subgroup analyses were performed to evaluate factors influencing extracellular vesicle therapy. Review Man3ager5.3 was used for data analysis. A total of 20 relevant articles were included in the present meta-analysis. The comprehensive analysis revealed that extracellular vesicles exerted a significant beneficial effect on neurobehavioral function, reducing the infarct volume and decreasing the apoptotic rate. Moreover, extracellular vesicles were found to promote nerve recovery by inhibiting pro-inflammatory factors (TNF-α, IL-1β and IL-6). On the whole, the present meta-analysis examined the combined effects of extracellular vesicles on nerve function, infarct volume, apoptosis and inflammation, which provides a foundation for the clinical study of extracellular vesicles.

Lethal pulmonary thromboembolism in mice induced by intravenous human umbilical cord mesenchymal stem cell-derived large extracellular vesicles in a dose- and tissue factor-dependent manner

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have obvious advantages over MSC therapy. But the strong procoagulant properties of MSC-EVs pose a potential risk of thromboembolism, an issue that remains insufficiently explored. In this study, we systematically investigated the procoagulant activity of large EVs derived from human umbilical cord MSCs (UC-EVs) both in vitro and in vivo. UC-EVs were isolated from cell culture supernatants. Mice were injected with UC-EVs (0.125, 0.25, 0.5, 1, 2, 4 μg/g body weight) in 100 μL PBS via the tail vein. Behavior and mortality were monitored for 30 min after injection. We showed that these UC-EVs activated coagulation in a dose- and tissue factor-dependent manner. UC-EVs-induced coagulation in vitro could be inhibited by addition of tissue factor pathway inhibitor. Notably, intravenous administration of high doses of the UC-EVs (1 μg/g body weight or higher) led to rapid mortality due to multiple thrombus formations in lung tissue, platelets, and fibrinogen depletion, and prolonged prothrombin and activated partial thromboplastin times. Importantly, we demonstrated that pulmonary thromboembolism induced by the UC-EVs could be prevented by either reducing the infusion rate or by pre-injection of heparin, a known anticoagulant. In conclusion, this study elucidates the procoagulant characteristics and mechanisms of large UC-EVs, details the associated coagulation risk during intravenous delivery, sets a safe upper limit for intravenous dose, and offers effective strategies to prevent such mortal risks when high doses of large UC-EVs are needed for optimal therapeutic effects, with implications for the development and application of large UC-EV-based as well as other MSC-EV-based therapies.

A call for standardization for secretome and extracellular vesicles in osteoarthritis: results show disease-modifying potential, but protocols are too heterogeneous-a systematic review

The currently available osteoarthritis (OA) treatments offer symptoms' relief without disease-modifying effects. Increasing evidence supports the role of human mesenchymal stem cells (MSCs) to drive beneficial effects provided by their secretome and extracellular vesicles (EVs), which includes trophic and biologically active factors. Aim of this study was to evaluate the in vitro literature to understand the potential of human secretome and EVs for OA treatment and identify trends, gaps, and potential translational challenges. A systematic review was performed on PubMed, Embase, and Web-of-Science, identifying 58 studies. The effects of secretome and EVs were analysed on osteoarthritic cells regarding anabolic, anti-apoptotic/anti-inflammatory and catabolic/pro-inflammatory/degenerative activity, chondroinduction, and immunomodulation. The results showed that MSC-derived EVs elicit an increase in proliferation and migration, reduction of cell death and inflammation, downregulation of catabolic pathways, regulation of immunomodulation, and promotion of anabolic processes in arthritic cells. However, a high heterogeneity in several technical or more applicative aspects emerged. In conclusion, the use of human secretome and EVs as strategy to address OA processes has overall positive effects and disease-modifying potential. However, it is crucial to reduce protocol variability and strive toward a higher standardization, which will be essential for the translation of this promising OA treatment from the in vitro research setting to the clinical practice.

The Discovery of Extracellular Vesicles and Their Emergence as a Next-Generation Therapy

From their humble discovery as cellular debris to cementing their natural capacity to transfer functional molecules between cells, the long-winded journey of extracellular vesicles (EVs) now stands at the precipice as a next-generation cell-free therapeutic tool to revolutionize modern-day medicine. This perspective provides a snapshot of the discovery of EVs to their emergence as a vibrant field of biology and the renaissance they usher in the field of biomedical sciences as therapeutic agents for cardiovascular pathologies. Rapid development of bioengineered EVs is providing innovative opportunities to overcome biological challenges of natural EVs such as potency, cargo loading and enhanced secretion, targeting and circulation half-life, localized and sustained delivery strategies, approaches to enhance systemic circulation, uptake and lysosomal escape, and logistical hurdles encompassing scalability, cost, and time. A multidisciplinary collaboration beyond the field of biology now extends to chemistry, physics, biomaterials, and nanotechnology, allowing rapid development of designer therapeutic EVs that are now entering late-stage human clinical trials.

Therapeutic potential of extracellular vesicles derived from human amniotic epithelial cells for perinatal cerebral and pulmonary injury

Lung and brain injury that occurs during the perinatal period leads to lifelong disability and is often driven and/or exacerbated by inflammation. Human amniotic epithelial cells (hAEC), which demonstrate immunomodulatory, anti-fibrotic, and regenerative capabilities, are being explored as a therapeutic candidate for perinatal injury. However, limitations regarding scalable manufacturing, storage, transport, and dose-related toxicity have impeded clinical translation. Isolated therapeutic extracellular vesicles (EVs) from stem and stem-like cells are thought to be key paracrine mediators of therapeutic efficacy. The unique characteristics of EVs suggest that they potentially circumvent the limitations of traditional cell-based therapies. However, given the novelty of EVs as a therapeutic, recommendations around ideal methods of production, isolation, storage, and delivery have not yet been created by regulatory agencies. In this concise review, we discuss the pertinence and limitations of cell-based therapeutics in perinatal medicine. We also review the preclinical evidence supporting the use of therapeutic EVs for perinatal therapy. Further, we summarize the arising considerations regarding adequate cell source, biodistribution, isolation and storage methods, and regulatory roadblocks for the development of therapeutic EVs.

Treg-Derived Extracellular Vesicles: Roles in Diseases and Theranostics

Regulatory T cells (Tregs), a subset of CD4+ T cells, are indispensable in maintaining immune self-tolerance and have been utilized in various diseases. Treg-derived extracellular vesicles (Treg-EVs) have been discovered to play an important role in the mechanism of Treg functions. As cell-derived membranous particles, EVs carry multiple bioactive substances that possess tremendous potential for theranostics. Treg-EVs are involved in numerous physiological and pathological processes, carrying proteins and miRNAs inherited from the parental cells. To comprehensively understand the function of Treg-EVs, here we reviewed the classification of Treg-EVs, the active molecules in Treg-EVs, their various applications in diseases, and the existing challenges for Treg-EVs based theranostics. This Review aims to clarify the feasibility and potential of Treg-EVs in diseases and theranostics, facilitating further research and application of Treg-EVs.

Extracellular Vesicles: An Emerging Clinical Opportunity in Musculoskeletal Disease

Extracellular vesicles (EVs) are important mediators of cell-to-cell communication in the extracellular space. These membranous nanoparticles carry various molecules, often referred to as "cargo," which are delivered to nearby target cells. In the past decade, developments in nanotechnology have allowed for various new laboratory techniques for the increased utilization of EVs in cellular and animal studies. Such techniques have evolved for the isolation, characterization, and delivery of EVs to biological tissues. This emerging technology has immense clinical potential for both diagnostic and therapeutic applications. Various EV cargo molecules, including DNA, RNA, and proteins, can act as pathological biomarkers. Furthermore, EVs derived from certain cell sources have shown therapeutic benefit in certain pathologies. In addition to their native therapeutic benefit, EVs can be engineered to carry and selectively deliver therapeutic agents. While EVs have gained increasing interest in various pathologies, few studies have compiled their clinical potential in musculoskeletal pathologies. To bridge this gap, we present an overview of EVs, introduce current laboratory preparation techniques, and outline the most recent literature regarding the potential therapeutic applications of EVs in musculoskeletal pathologies.

Intraocular mRNA delivery with endogenous MmPEG10-based virus-like particles

Virus-like particles (VLP) are a promising tool for intracellular gene delivery, yet their potential in ocular gene therapy remains underexplored. In this study, we bridged this knowledge gap by demonstrating the successful generation and application of vesicular stomatitis virus glycoprotein (VSVG)-pseudotyped mouse PEG10 (MmPEG10)-VLP for intraocular mRNA delivery. Our findings revealed that PEG10-VLP can efficiently deliver GFP mRNA to adult retinal pigment epithelial cell line-19 (ARPE-19) cells, leading to transient expression. Moreover, we showed that MmPEG10-VLP can transfer SMAD7 to inhibit epithelial-mesenchymal transition (EMT) in RPE cells effectively. In vivo experiments further substantiated the potential of these vectors, as subretinal delivery into adult mice resulted in efficient transduction of retinal pigment epithelial (RPE) cells and GFP reporter gene expression without significant immune response. However, intravitreal injection did not yield efficient ocular expression. We also evaluated the transduction characteristics of MmPEG10-VLP following intracameral delivery, revealing transient GFP protein expression in corneal endothelial cells without significant immunotoxicities. In summary, our study established that VSVG pseudotyped MmPEG10-based VLP can transduce mitotically inactive RPE cells and corneal endothelial cells in vivo without triggering an inflammatory response, underscoring their potential utility in ocular gene therapy.

Neutrophil-derived nanovesicles deliver IL-37 to mitigate renal ischemia-reperfusion injury via endothelial cell targeting

Renal ischemia-reperfusion injury (IRI) is one of the most important causes of acute kidney injury (AKI). Interleukin (IL)-37 has been suggested as a novel anti-inflammatory factor for the treatment of IRI, but its application is still limited by its low stability and delivery efficiency. In this study, we reported a novel engineered method to efficiently and easily prepare neutrophil membrane-derived vesicles (N-MVs), which could be utilized as a promising vehicle to deliver IL-37 and avoid the potential side effects of neutrophil-derived natural extracellular vesicles. N-MVs could enhance the stability of IL-37 and targetedly deliver IL-37 to damaged endothelial cells of IRI kidneys via P-selectin glycoprotein ligand-1 (PSGL-1). In vitro and in vivo evidence revealed that N-MVs encapsulated with IL-37 (N-MV@IL-37) could inhibit endothelial cell apoptosis, promote endothelial cell proliferation and angiogenesis, and decrease inflammatory factor production and leukocyte infiltration, thereby ameliorating renal IRI. Our study establishes a promising delivery vehicle for the treatment of renal IRI and other endothelial damage-related diseases.

Small Intestinal Endocrine Cell Derived Exosomal ACE2 Protects Islet β-Cell Function by Inhibiting the Activation of NLRP3 Inflammasome and Reducing β-Cell Pyroptosis

Background

The "gut-islets axis" is an important endocrine signaling axis that regulates islets function by modulating the gut microbiota and endocrine metabolism within the gut. However, the specific mechanisms and roles of the intestine in islets regulation remain unclear. Recent studies investigated that exosomes derived from gut microbiota can transport signals to remotely regulate islets β-cell function, suggesting the possibility of novel signaling pathways mediated by gut exosomes in the regulation of the "gut-islet axis.".

Methods

The exosomes were isolated from the intestinal enteroendocrine cell-line STC-1cells culture supernatants treated with palmitate acid (PA) or BSA. Metabolic stress models were established by separately subjecting MIN6 cells to PA stimulation and feeding mice with a high-fat diet. Intervention with exosomes in vitro and in vivo to assess the biological effects of exosomes on islets β cells under metabolic stress. The Mas receptor antagonist A779 and ACE2ko mice were used to evaluate the role of exosomal ACE2.

Results

We found ACE2, a molecule that plays a crucial role in the regulation of islets function, is abundantly expressed in exosomes derived from STC-1 under physiological normal condition (NCEO). These exosomes cannot only be taken up by β-cells in vitro but also selectively transported to the islets in vivo. Following intervention with NCEXO, both Min6 cells in a lipotoxic environment and mice on a high-fat diet exhibited significant improvements in islets β-cell function and β-cell mass. Further investigations demonstrated that these protective effects are attributed to exosomal ACE2, as ACE2 inhibits NLRP3 inflammasome activation and reduces β-cell pyroptosis.

Conclusion

ACE2-enriched exosomes from the gut can selectively target islets, subsequently inhibiting NLRP3 inflammasome activation and β cell pyroptosis, thereby restoring islets β cell function under metabolic stress. This study provides novel insights into therapeutic strategies for the prevention and treatment of obesity and diabetes.

Extracellular vesicles in cancer cachexia: deciphering pathogenic roles and exploring therapeutic horizons

Cancer cachexia (CC) is a debilitating syndrome that affects 50-80% of cancer patients, varying in incidence by cancer type and significantly diminishing their quality of life. This multifactorial syndrome is characterized by muscle and fat loss, systemic inflammation, and metabolic imbalance. Extracellular vesicles (EVs), including exosomes and microvesicles, play a crucial role in the progression of CC. These vesicles, produced by cancer cells and others within the tumor environment, facilitate intercellular communication by transferring proteins, lipids, and nucleic acids. A comprehensive review of the literature from databases such as PubMed, Scopus, and Web of Science reveals insights into the formation, release, and uptake of EVs in CC, underscoring their potential as diagnostic and prognostic biomarkers. The review also explores therapeutic strategies targeting EVs, which include modifying their release and content, utilizing them for drug delivery, genetically altering their contents, and inhibiting key cachexia pathways. Understanding the role of EVs in CC opens new avenues for diagnostic and therapeutic approaches, potentially mitigating the syndrome's impact on patient survival and quality of life.

Berberine mitigates diclofenac-induced intestinal mucosal mechanical barrier dysfunction through the restoration of autophagy by inhibiting exosome-mediated lncRNA H19

Small intestine damage caused by diclofenac is called diclofenac enteropathy. Berberine (BBR), a class of isoquinoline alkaloids derived from Berberis vulgaris and Phellodendron amurense, is widely used in intestinal diseases. The present study evaluated the protective effect of BBR on the intestinal mucosal mechanical barrier in diclofenac enteropathy and its possible action mechanism. The in vitro animal experiment revealed that BBR downregulated the expression of long non-coding RNA H19 (lncRNA H19) in the small intestine and exosomes. In the co-culture experiment involving exosomes and intestinal epithelial cell-6 (IEC-6) cells, the results of qRT-PCR, western blotting, and immunofluorescence assays demonstrated that the elevated expression of lncRNA H19 in the small intestine, conveyed via exosomes derived from the diclofenac group, suppressed the expression levels of autophagy-associated protein 5 (Atg 5) and light chain 3 (LC 3), as well as and the tight junction (TJ) proteins zonula occludens-1 (ZO-1), claudin-1, and occluding, relative to the control group. BBR treatment attenuated exosomal lncRNA H19 levels, upregulated the expression of Atg5 and LC3 expression, enhanced TJ protein expression, and increased the light chain 3 (LC3)-II/LC3-I ratio. These findings significantly elucidated that BBR promoted the restoration of autophagy in IECs by inhibiting exosomal lncRNA H19, thereby mitigating the impairment of the intestinal mucosal mechanical barrier function in diclofenac enteropathy. The process involving exosomal lncRNA H19 regulating autophagy, thereby affecting the intestinal mucosal mechanical barrier, offers a novel perspective for the application of BBR in the treatment of diclofenac enteropathy.

Pure total flavonoids from Citrus ameliorate NSAIDs-induced intestinal mucosal injury via regulation of exosomal LncRNA H19 and protective autophagy

Introduction

Non-steroid anti-inflammatory drugs (NSAIDs) are a class of prescription drugs with antipyretic, analgesic, anti-inflammatory, and antiplatelet effects. However, long-term use of NSAIDs will disrupt the intestinal mucosal barrier, causing erosion, ulcers, bleeding, and even perforation. Pure total flavonoids from Citrus (PTFC) is extracted from the dried peel of Citrus, showing a protective effect on intestinal mucosal barrier with unclear mechanisms.

Methods

In the present study, we used diclofenac (7.5 mg kg-1, i.g.) to induce a rat model of NSAIDs-related intestinal lesions. PTFC (50, 75, 100 mg·kg-1 d-1, i.g.) was administered 9 days before the initial diclofenac administration, followed by co-administration on the last 5 days. Exosomes were identified by western blotting and transmission electron microscopy (TEM), and then co-cultured with IEC-6 cells. The expression of long non-coding RNA (lncRNA) H19, autophagy-related 5 (Atg5), ZO-1, Occludin, and Claudin-1 were detected by quantitative real-time PCR (qRT-PCR). The expression of light chain 3 (LC3)-I, LC3-II, ZO-1, Occludin and Claudin-1 proteins was tested by western blotting. The localization of both exosomes and autophagosomes was examined by immunofluorescent technique.

Results

The treatment of PTFC attenuated intestinal mucosal mechanical barrier function disturbance in diclofenac-induced NSAIDs rats. IEC-6 cells co-cultured with NSAIDs rats-derived exosomes possessed the lowest levels of protective autophagy, and severe intestinal barrier injuries. Cells co-cultured with the exosomes extracted from rats administrated PTFC exhibited an improvement of autophagy and intestinal mucosal mechanical barrier function. The prevention effect was proportional to the concentration of PTFC administered.

Conclusion

PTFC ameliorated NSAIDs-induced intestinal mucosal injury by down-regulating exosomal lncRNA H19 and promoting autophagy.

Extracellular vesicles produced by HIV-1 Nef-expressing cells induce myelin impairment and oligodendrocyte damage in the mouse central nervous system

HIV-associated neurocognitive disorders (HAND) are a spectrum of cognitive impairments that continue to affect approximately half of all HIV-positive individuals despite effective viral suppression through antiretroviral therapy (ART). White matter pathologies have persisted in the ART era, and the degree of white matter damage correlates with the degree of neurocognitive impairment in patients with HAND. The HIV protein Nef has been implicated in HAND pathogenesis, but its effect on white matter damage has not been well characterized. Here, utilizing in vivo, ex vivo, and in vitro methods, we demonstrate that Nef-containing extracellular vesicles (Nef EVs) disrupt myelin sheaths and inflict damage upon oligodendrocytes within the murine central nervous system. Intracranial injection of Nef EVs leads to reduced myelin basic protein (MBP) staining and a decreased number of CC1 + oligodendrocytes in the corpus callosum. Moreover, cerebellar slice cultures treated with Nef EVs exhibit diminished MBP expression and increased presence of unmyelinated axons. Primary mixed brain cultures and enriched oligodendrocyte precursor cell cultures exposed to Nef EVs display a decreased number of O4 + cells, indicative of oligodendrocyte impairment. These findings underscore the potential contribution of Nef EV-mediated damage to oligodendrocytes and myelin maintenance in the pathogenesis of HAND.

Critical parameters to standardize the size and concentration determination of nanomaterials by nanoparticle tracking analysis

The size and concentration are critical for the diagnostic and therapeutic applications of nanomaterials but the accurate measurement remains challenging. Nanoparticle tracking analysis (NTA) is widely used for size and concentration determination. However, highly repeatable standard operating procedures (SOPs) are absent. We adopted the "search-evaluate-test" strategy to standardize the measurement by searching the critical parameters. The particles per frame are linearly proportional to the sample concentration and the measured results are more accurate and repeatable when the concentration is 108-109 particles/ml. The optimal detection threshold is around 5. The optimal camera level is such that it allows clear observation of particles without diffractive rings and overexposure. The optimal speed is ≤ 50 in AU and ∼ 10 μl/min in flow rate. We then evaluated the protocol using polydisperse polystyrene particles and we found that NTA could discriminate particles in bimodal mixtures with high size resolution but the performance on multimodal mixtures is not as good as that of resistive pulse sensing (RPS). We further analyzed the polystyrene particles, SiO2 particles, and biological samples by NTA following the SOPs. The size and concentration measured by NTA differentially varies to those determined by RPS and transmission electron microscopy.

Novel loading protocol combines highly efficient encapsulation of exogenous therapeutic toxin with preservation of extracellular vesicles properties, uptake and cargo activity

Extracellular vesicles (EVs) have mostly been investigated as carriers of biological therapeutics such as proteins and RNA. Nevertheless, small-molecule drugs of natural or synthetic origin have also been loaded into EVs, resulting in an improvement of their therapeutic properties. A few methods have been employed for EV cargo loading, but poor yield and drastic modifications of vesicles remain unsolved challenges. We tested a different strategy based on temporary pH alteration through incubation of EVs with alkaline sodium carbonate, which resulted in conspicuous exogenous molecule incorporation. In-depth characterization showed that vesicle size, morphology, composition, and uptake were not affected. Our method was more efficient than gold-standard electroporation, particularly for a potential therapeutic toxin: the plant Ribosome Inactivating Protein saporin. The encapsulated saporin resulted protected from degradation, and was efficiently conveyed to receiving cancer cells and triggered cell death. EV-delivered saporin was more cytotoxic compared to the free toxin. This approach allows both the structural preservation of vesicle properties and the transfer of protected cargo in the context of drug delivery.

Natural Killer Cell‐Derived Extracellular Vesicles as Potential Anti‐Viral Nanomaterials

In viral infections, natural killer (NK) cells exhibit anti-viral activity by inducing apoptosis in infected host cells and impeding viral replication through heightened cytokine release. Extracellular vesicles derived from NK cells (NK-EVs) also contain the membrane composition, homing capabilities, and cargo that enable anti-viral activity. These characteristics, and their biocompatibility and low immunogenicity, give NK-EVs the potential to be a viable therapeutic platform. This study characterizes the size, EV-specific protein expression, cell internalization, biocompatibility, and anti-viral miRNA cargo to evaluate the anti-viral properties of NK-EVs. After 48 h of NK-EV incubation in inflamed A549 lung epithelial cells, or conditions that mimic lung viral infections such as during COVID-19, cells treated with NK-EVs exhibit upregulated anti-viral miRNA cargo (miR-27a, miR-27b, miR-369-3p, miR-491-5p) compared to the non-treated controls and cells treated with control EVs derived from lung epithelial cells. Additionally, NK-EVs effectively reduce expression of viral RNA and pro-inflammatory cytokine (TNF-α, IL-8) levels in SARS-CoV-2 infected Vero E6 kidney epithelial cells and in infected mice without causing tissue damage while significantly decreasing pro-inflammatory cytokine compared to non-treated controls. Herein, this work elucidates the potential of NK-EVs as safe, anti-viral nanomaterials, offering a promising alternative to conventional NK cell and anti-viral therapies.

Extracellular Vesicles in Pathophysiology: A Prudent Target That Requires Careful Consideration

Extracellular vesicles (EVs) are membrane-bound particles released by cells to perform multitudes of biological functions. Owing to their significant implications in diseases, the pathophysiological role of EVs continues to be extensively studied, leading research to neglect the need to explore their role in normal physiology. Despite this, many identified physiological functions of EVs, including, but not limited to, tissue repair, early development and aging, are attributed to their modulatory role in various signaling pathways via intercellular communication. EVs are widely perceived as a potential therapeutic strategy for better prognosis, primarily through utilization as a mode of delivery vehicle. Moreover, disease-associated EVs serve as candidates for the targeted inhibition by pharmacological or genetic means. However, these attempts are often accompanied by major challenges, such as off-target effects, which may result in adverse phenotypes. This renders the clinical efficacy of EVs elusive, indicating that further understanding of the specific role of EVs in physiology may enhance their utility. This review highlights the essential role of EVs in maintaining cellular homeostasis under different physiological settings, and also discusses the various aspects that may potentially hinder the robust utility of EV-based therapeutics.

Exploring the role of epicardial adipose-tissue-derived extracellular vesicles in cardiovascular diseases

Epicardial adipose tissue (EAT) is a fat depot located between the myocardium and the visceral layer of the epicardium, which, owing to its location, can influence surrounding tissues and can act as a local transducer of systemic inflammation. The mechanisms upon which such influence depends on are however unclear. Given the role EAT undoubtedly has in the scheme of cardiovascular diseases (CVDs), understanding the impact of its cellular components is of upmost importance. Extracellular vesicles (EVs) constitute promising candidates to fill the gap in the knowledge concerning the unexplored mechanisms through which EAT promotes onset and progression of CVDs. Owing to their ability of transporting active biomolecules, EAT-derived EVs have been reported to be actively involved in the pathogenesis of ischemia/reperfusion injury, coronary atherosclerosis, heart failure, and atrial fibrillation. Exploring the precise functions EVs exert in this context may aid in connecting the dots between EAT and CVDs.

Insights into optimizing exosome therapies for acute skin wound healing and other tissue repair

Exosome therapy holds great promise as a novel approach to improve acute skin wound healing. This review provides a comprehensive overview of the current understanding of exosome biology and its potential applications in acute skin wound healing and beyond. Exosomes, small extracellular vesicles secreted by various stem cells, have emerged as potent mediators of intercellular communication and tissue repair. One advantage of exosome therapy is its ability to avoid potential risks associated with stem cell therapy, such as immune rejection or stem cells differentiating into unwanted cell types. However, further research is necessary to optimize exosome therapy, not only in the areas of exosome isolation, characterization, and engineering, but also in determining the optimal dose, timing, administration, and frequency of exosome therapy. Thus, optimization of exosome therapy is critical for the development of more effective and safer exosome-based therapies for acute skin wound healing and other diseases induced by cancer, ischemia, or inflammation. This review provides valuable insights into the potential of exosome therapy and highlights the need for further research to optimize exosome therapy for clinical use.

Human umbilical cord mesenchymal stem cell-derived exosomes loaded into a composite conduit promote functional recovery after peripheral nerve injury in rats

Complete transverse injury of peripheral nerves is challenging to treat. Exosomes secreted by human umbilical cord mesenchymal stem cells are considered to play an important role in intercellular communication and regulate tissue regeneration. In previous studies, a collagen/hyaluronic acid sponge was shown to provide a suitable regeneration environment for Schwann cell proliferation and to promote axonal regeneration. This three-dimensional (3D) composite conduit contains a collagen/hyaluronic acid inner sponge enclosed in an electrospun hollow poly (lactic-co-glycolic acid) tube. However, whether there is a synergy between the 3D composite conduit and exosomes in the repair of peripheral nerve injury remains unknown. In this study, we tested a comprehensive strategy for repairing long-gap (10 mm) peripheral nerve injury that combined the 3D composite conduit with human umbilical cord mesenchymal stem cell-derived exosomes. Repair effectiveness was evaluated by sciatic functional index, sciatic nerve compound muscle action potential recording, recovery of muscle mass, measuring the cross-sectional area of the muscle fiber, Masson trichrome staining, and transmission electron microscopy of the regenerated nerve in rats. The results showed that transplantation of the 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes promoted peripheral nerve regeneration and restoration of motor function, similar to autograft transplantation. More CD31-positive endothelial cells were observed in the regenerated nerve after transplantation of the loaded conduit than after transplantation of the conduit without exosomes, which may have contributed to the observed increase in axon regeneration and distal nerve reconnection. Therefore, the use of a 3D composite conduit loaded with human umbilical cord mesenchymal stem cell-derived exosomes represents a promising cell-free therapeutic option for the treatment of peripheral nerve injury.

Effects of Salmonella Outer Membrane Vesicles on Intestinal Microbiota and Intestinal Barrier Function

Salmonella enterica is one of the most important zoonotic pathogens causing foodborne gastroenteritis worldwide. Outer membrane vesicles (OMVs) are lipid-bilayer vesicles produced by Gram-negative bacteria, which contain biologically active components. We hypothesized that OMVs are an important weapon of S. enterica to initiate enteric diseases pathologies. In this study, the effects of S. enterica OMVs (SeOMVs) on intestinal microbiota and intestinal barrier function were investigated. In vitro fecal culture experiments showed that alpha diversity indexes and microbiota composition were altered by SeOMV supplementation. SeOMV supplementation showed an increase of pH, a decrease of OD630 and total short chain fatty acid (SCFA) concentrations. In vitro IPEC-J2 cells culture experiments showed that SeOMV supplementation did not affect the IPEC-J2 cell viability and the indicated genes expression. In vivo experiments in mice showed that SeOMVs had adverse effects on average daily gain (p < 0.05) and feed:gain ratio (p < 0.05), and had a tendency to decrease the final body weight (p = 0.073) in mice. SeOMV administration decreased serum interleukin-10 level (p < 0.05), decreased the relative abundance of bacteria belonging to the genera BacC-u-018 and Akkermansia (p < 0.05). Furthermore, SeOMV administration damaged the ileum mucosa (p < 0.05). These findings suggest that SeOMVs play an important role in the activation of intestinal inflammatory response induced by S. enterica, and downregulation of SCFA-producing bacteria is a possible mechanism.

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

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

Extracellular vesicle-mediated pre-metastatic niche formation via altering host microenvironments

The disordered growth, invasion and metastasis of cancer are mainly attributed to bidirectional cell-cell interactions. Extracellular vesicles (EVs) secreted by cancer cells are involved in orchestrating the formation of pre-metastatic niches (PMNs). Tumor-derived EVs mediate bidirectional communication between tumor and stromal cells in local and distant microenvironments. EVs carrying mRNAs, small RNAs, microRNAs, DNA fragments, proteins and metabolites determine metastatic organotropism, enhance angiogenesis, modulate stroma cell phenotypes, restructure the extracellular matrix, induce immunosuppression and modify the metabolic environment of organs. Evidence indicates that EVs educate stromal cells in secondary sites to establish metastasis-supportive microenvironments for seeding tumor cells. In this review, we provide a comprehensive overview of PMN formation and the underlying mechanisms mediated by EVs. Potential approaches to inhibit cancer metastasis by inhibiting the formation of PMNs are also presented.

Exosomes From IgE-Stimulated Mast Cells Aggravate Asthma-Mediated Atherosclerosis Through circRNA CDR1as-Mediated Endothelial Cell Dysfunction in Mice

BACKGROUND

IgE has been known for mediating endothelial cell dysfunction and mast cell (MC) activation to fuel asthma-aggravated high-fat diet-induced atherosclerosis. However, it remains unclear for the mechanism of asthma-mediated atherosclerosis, especially the potential involvement of IgE in the exacerbation of asthma-mediated atherosclerosis with a standard laboratory diet, and the cross talk between endothelial cells and MCs.

METHODS

Asthma-mediated atherosclerosis mice models under a standard laboratory diet and FcεR1 knock-out mice were used to determine the role of IgE-FcεR1 signaling in asthma-mediated atherosclerosis, which was assessed by Oil Red O staining and immunohistochemistry. Various in vitro assays including nanoparticle tracking analysis and transmission electron microscopy were used to evaluate exosome characteristics. Immunofluorescence and fluorescent in situ hybridization approaches were used to evaluate the effect and mechanism of MC-secreted exosomes encapsulated circular RNA CDR1as (cerebellar degeneration-related 1 antisense) on endothelial cells in vivo and in vitro. Finally, cohort studies examined the plasma CDR1as levels in patients with atherosclerosis with or without allergies.

RESULTS

Asthma mice with a standard laboratory diet showed increased atherosclerotic lesions and inflammatory infiltration depending on IgE-FcεR1 signal. FcεR1 knockout mice and blockage of IgE-FcεR1 signaling with IgE monoclonal antibody, omalizumab, all significantly alleviated asthma-mediated atherosclerosis and vascular inflammatory remodeling. Anti-inflammation with dexamethasone and stabilization of MC with cromolyn partially alleviated atherosclerotic lesions and mitigated the inflammatory infiltration in arteries. Mechanistically, IgE stimulation upregulates MC CDR1as expression in exosomes and upregulates the endothelial cell adhesive factors VCAM-1 (vascular cell adhesion molecule-1) and ICAM-1 (intercellular adhesion molecule-1) via the CDR1as-FUS (fused in sarcoma)-phos-p65 axis. Knockdown of CDR1as in vivo significantly decreased the endothelial adhesion function and mitigated asthma-mediated atherosclerosis. Furthermore, a cohort study indicated higher plasma CDR1as levels in patients with atherosclerosis with allergies than in patients with atherosclerosis and healthy controls.

CONCLUSIONS

Exosomes from IgE-stimulated MCs aggravated atherosclerosis through circular RNA CDR1as-mediated endothelial dysfunction, providing a novel insight into asthma-mediated atherosclerosis and potential diagnostic and therapeutic targets.

Harnessing the power of goat milk-derived extracellular vesicles for medical breakthroughs: A review

Research into goat milk-derived extracellular vesicles (GMVs) has grown in popularity in recent years owing to their potential uses in several sectors, including medicine. GMVs are tiny, lipid-bound structures that cells secrete and use to transport bioactive substances like proteins, lipids, and nucleic acids. They may be extracted from different body fluids, including blood, urine, and milk, and have been found to play crucial roles in cell-to-cell communication. GMVs are a promising field of study with applications in preventing and treating various disorders. Their immune-modulating properties, for instance, have been investigated, and they have shown promise in treating autoimmune illnesses and cancer. They may be loaded with therapeutic compounds and directed to particular cells or tissues, but they have also been studied for their potential use as drug-delivery vehicles. Goat milk extracellular vesicles are an intriguing study topic with many possible benefits. Although more study is required to thoroughly understand their functioning and prospective applications, they provide a promising path for creating novel medical treatments and technology.

Hyperthermic shift and cell engineering increase small extracellular vesicle production in HEK293F cells

Although small extracellular vesicles (sEVs) have promising features as an emerging therapeutic format for a broad spectrum of applications, for example, blood-brain-barrier permeability, low immunogenicity, and targeted delivery, economic manufacturability will be a crucial factor for the therapeutic applicability of sEVs. In the past, bioprocess optimization and cell line engineering improved titers of classical biologics multifold. We therefore performed a design of experiments (DoE) screening to identify beneficial bioprocess conditions for sEV production in HEK293F suspension cells. Short-term hyperthermia at 40°C elevated volumetric productivity 5.4-fold while sEVs displayed improved exosomal characteristics and cells retained >90% viability. Investigating the effects of hyperthermia via transcriptomics and proteomics analyses, an expectable, cellular heat-shock response was found together with an upregulation of many exosome biogenesis and vesicle trafficking related molecules, which could cause the productivity boost in tandem with heat shock proteins (HSPs), like HSP90 and HSC70. Because of these findings, a selection of 44 genes associated with exosome biogenesis, vesicle secretion machinery, or heat-shock response was screened for their influence on sEV production. Overexpression of six genes, CHMP1A, CHMP3, CHMP5, VPS28, CD82, and EZR, significantly increased both sEV secretion and titer, making them suitable targets for cell line engineering.

Exosome lncRNA IFNG-AS1 derived from mesenchymal stem cells of human adipose ameliorates neurogenesis and ASD-like behavior in BTBR mice

BACKGROUND

The transplantation of exosomes derived from human adipose-derived mesenchymal stem cells (hADSCs) has emerged as a prospective cellular-free therapeutic intervention for the treatment of neurodevelopmental disorders (NDDs), as well as autism spectrum disorder (ASD). Nevertheless, the efficacy of hADSC exosome transplantation for ASD treatment remains to be verified, and the underlying mechanism of action remains unclear.

RESULTS

The exosomal long non-coding RNAs (lncRNAs) from hADSC and human umbilical cord mesenchymal stem cells (hUCMSC) were sequenced and 13,915 and 729 lncRNAs were obtained, respectively. The lncRNAs present in hADSC-Exos encompass those found in hUCMSC-Exos and are associated with neurogenesis. The biodistribution of hADSC-Exos in mouse brain ventricles and organoids was tracked, and the cellular uptake of hADSC-Exos was evaluated both in vivo and in vitro. hADSC-Exos promote neurogenesis in brain organoid and ameliorate social deficits in ASD mouse model BTBR T + tf/J (BTBR). Fluorescence in situ hybridization (FISH) confirmed lncRNA Ifngas1 significantly increased in the prefrontal cortex (PFC) of adult mice after hADSC-Exos intraventricular injection. The lncRNA Ifngas1 can act as a molecular sponge for miR-21a-3p to play a regulatory role and promote neurogenesis through the miR-21a-3p/PI3K/AKT axis.

CONCLUSION

We demonstrated hADSC-Exos have the ability to confer neuroprotection through functional restoration, attenuation of neuroinflammation, inhibition of neuronal apoptosis, and promotion of neurogenesis both in vitro and in vivo. The hADSC-Exos-derived lncRNA IFNG-AS1 acts as a molecular sponge and facilitates neurogenesis via the miR-21a-3p/PI3K/AKT signaling pathway, thereby exerting a regulatory effect. Our findings suggest a potential therapeutic avenue for individuals with ASD.

Tumorigenic and tumoricidal properties of exosomes in cancers; a forward look

In recent decades, emerging data have highlighted the critical role of extracellular vesicles (EVs), especially (exosomes) Exos, in the progression and development of several cancer types. These nano-sized vesicles are released by different cell lineages within the cancer niche and maintain a suitable platform for the interchange of various signaling molecules in a paracrine manner. Based on several studies, Exos can transfer oncogenic factors to other cells, and alter the activity of immune cells, and tumor microenvironment, leading to the expansion of tumor cells and metastasis to the remote sites. It has been indicated that the cell-to-cell crosstalk is so complicated and a wide array of factors are involved in this process. How and by which mechanisms Exos can regulate the behavior of tumor cells and non-cancer cells is at the center of debate. Here, we scrutinize the molecular mechanisms involved in the oncogenic behavior of Exos released by different cell lineages of tumor parenchyma. Besides, tumoricidal properties of Exos from various stem cell (SC) types are discussed in detail.

Mesenchymal stromal cell derived extracellular vesicles as a therapeutic tool: immune regulation, MSC priming, and applications to SLE

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by a dysfunction of the immune system. Mesenchymal stromal cell (MSCs) derived extracellular vesicles (EVs) are nanometer-sized particles carrying a diverse range of bioactive molecules, such as proteins, miRNAs, and lipids. Despite the methodological disparities, recent works on MSC-EVs have highlighted their broad immunosuppressive effect, thus driving forwards the potential of MSC-EVs in the treatment of chronic diseases. Nonetheless, their mechanism of action is still unclear, and better understanding is needed for clinical application. Therefore, we describe in this review the diverse range of bioactive molecules mediating their immunomodulatory effect, the techniques and possibilities for enhancing their immune activity, and finally the potential application to SLE.

ASC-expressing pyroptotic extracellular vesicles alleviate sepsis by protecting B cells

Pyroptosis is an inflammatory programmed cell death process characterized by membrane rupture. Interestingly, pyroptotic cells can generate plenty of nanosized vesicles. Non-inflammatory apoptotic cell death-derived apoptotic vesicles (apoVs) were systemically characterized and displayed multiple physiological functions and therapeutic potentials. However, the characteristics of pyroptotic cell-generated extracellular vesicles (EVs) are largely unknown. Here, we identified a group of pyroptotic EVs (pyroEVs) from in vitro cultured pyroptotic mesenchymal stem cells (MSCs), as well as from septic mouse blood. Compared with apoVs, pyroEVs express similar levels of annexin V, calreticulin, and common EV markers, but express a decreased level of apoptotic marker cleave caspase-3. PyroEVs, but not apoVs and exosomes, specifically express pyroptotic maker apoptosis-associated speck-like protein containing CARD (ASC). More importantly, MSC-derived pyroEVs protect B cells in the spleen and bone marrow to relieve inflammatory responses and enhance the survival rate of the septic mice. Mechanistically, pyroEV membrane-expressed ASC binds to B cells to repress cell death by repressing Toll-like receptor 4. This study uncovered the characteristics of pyroEVs and their therapeutic role in sepsis and B cell-mediated immune response.

Lyoprotectant Constituents Suited for Lyophilization and Reconstitution of Stem-Cell-Derived Extracellular Vesicles

Stem-cell-derived extracellular vesicles (EVs) are emerging as an alternative approach to stem cell therapy. Successful lyophilization of EVs could enable convenient storage and distribution of EV medicinal products at room temperature for long periods, thus considerably increasing the accessibility of EV therapeutics to patients. In this study, we aimed to identify an appropriate lyoprotectant composition for the lyophilization and reconstitution of stem-cell-derived EVs. MSC-derived EVs were lyophilized using different lyoprotectants, such as dimethyl sulfoxide, mannitol, trehalose, and sucrose, at varying concentrations. Our results revealed that a mixture of trehalose and sucrose at high concentrations could support the formation of amorphous ice by enriching the amorphous phase of the solution, which successfully inhibited the acceleration of buffer component crystallization during lyophilization. Lyophilized and reconstituted EVs were thoroughly evaluated for concentration and size, morphology, and protein and RNA content. The therapeutic effects of the reconstituted EVs were examined using a tube formation assay with human umbilical vein endothelial cells. After rehydration of the lyophilized EVs, most of their generic characteristics were well-maintained, and their therapeutic capacity recovered to levels similar to those of freshly collected EVs. The concentrations and morphologies of the lyophilized EVs were similar to the initial features of the fresh EV group until day 30 at room temperature, although their therapeutic capacity appeared to decrease after 7 days. Our study suggests an appropriate composition of lyoprotectants, particularly for EV lyophilization, which could encourage the applications of stem-cell-derived EV therapeutics in the health industry.

Exosome-specific loading Sox10 for the treatment of Cuprizone-induced demyelinating model

Demyelination is a pathological feature commonly observed in various central nervous system diseases. It is characterized by the aggregation of oligodendrocyte progenitor cells (OPCs) in the lesion area, which face difficulties in differentiating into mature oligodendrocytes (OLGs). The differentiation of OPCs requires the presence of Sox10, but its expression decreases under pathological conditions. Therefore, we propose a therapeutic strategy to regulate OPCs differentiation and achieve myelin repair by endogenously loading Sox10 into exosomes. To accomplish this, we generated a lentivirus-armed Sox10 that could anchor to the inner surface of the exosome membrane. We then infected HEK293 cells to obtain exosomes with high expression of Sox10 (exosomes-Sox10, ExoSs). In vitro, experiments confirmed that both Exos and ExoSs can be uptaken by OPCs, but only ExoSs exhibit a pro-differentiation effect on OPCs. In vivo, we administered PBS, Exos, and ExoSs to cuprizone-induced demyelinating mice. The results demonstrated that ExoSs can regulate the differentiation of PDGFRα+ OPCs into APC+ OLGs and reduce myelin damage in the corpus callosum region of the mouse brain compared to other groups. Further testing suggests that Sox10 may have a reparative effect on the myelin sheath by enhancing the expression of MBP, possibly facilitated by the exosome delivery of the protein into the lesion. This endogenously loaded technology holds promise as a strategy for protein-based drugs in the treatment of demyelinating diseases.

Potential Use of Extracellular Vesicles in the Treatment of Intervertebral Disc Degeneration

Intervertebral disc degeneration (IVDD) is a major cause of low back pain, and several studies have evaluated the efficacy of extracellular vesicles (EVs) in the treatment of IVDD. The databases PubMed, Embase, and Cochrane Library were systematically searched from inception to the end of 2022 to identify studies investigating the therapeutic potential of cell-derived EVs for IVDD treatment. The following outcome measures were utilized: magnetic resonance imaging (MRI) Pfirrmann grading system, disc height index (DHI), histological grading, and apoptosis rate. A comprehensive meta-analysis was conducted, including a total of 13 articles comprising 19 studies involving 218 experimental animals. Comparative analysis between normal cell-derived EVs and placebo revealed significant reductions in MRI grade, increased DHI values, decreased nucleus pulposus cell apoptosis rates, and improved tissue grades. These findings collectively demonstrate the effective inhibition of IVDD through the application of EVs derived from cells. In conclusion, this study provides an updated synthesis of evidence supporting the efficacy of EVs as a promising therapeutic approach for IVDD treatment.

Advances in extracellular vesicle-based combination therapies for spinal cord injury

Spinal cord injury is a severe insult to the central nervous system that causes persisting neurological deficits. The currently available treatments involve surgical, medical, and rehabilitative strategies. However, none of these techniques can markedly reverse neurological deficits. Recently, extracellular vesicles from various cell sources have been applied to different models of spinal cord injury, thereby generating new cell-free therapies for the treatment of spinal cord injury. However, the use of extracellular vesicles alone is still associated with some notable shortcomings, such as their uncertainty in targeting damaged spinal cord tissues and inability to provide structural support to damaged axons. Therefore, this paper reviews the latest combined strategies for the use of extracellular vesicle-based technology for spinal cord injury, including the combination of extracellular vesicles with nanoparticles, exogenous drugs and/or biological scaffold materials, which facilitate the targeting ability of extracellular vesicles and the combinatorial effects with extracellular vesicles. We also highlight issues relating to the clinical transformation of these extracellular vesicle-based combination strategies for the treatment of spinal cord injury.

Extracellular vesicles associated microRNAs: Their biology and clinical significance as biomarkers in gastrointestinal cancers

Gastrointestinal (GI) cancers, including colorectal, gastric, esophageal, pancreatic, and liver, are associated with high mortality and morbidity rates worldwide. One of the underlying reasons for the poor survival outcomes in patients with these malignancies is late disease detection, typically when the tumor has already advanced and potentially spread to distant organs. Increasing evidence indicates that earlier detection of these cancers is associated with improved survival outcomes and, in some cases, allows curative treatments. Consequently, there is a growing interest in the development of molecular biomarkers that offer promise for screening, diagnosis, treatment selection, response assessment, and predicting the prognosis of these cancers. Extracellular vesicles (EVs) are membranous vesicles released from cells containing a repertoire of biological molecules, including nucleic acids, proteins, lipids, and carbohydrates. MicroRNAs (miRNAs) are the most extensively studied non-coding RNAs, and the deregulation of miRNA levels is a feature of cancer cells. EVs miRNAs can serve as messengers for facilitating interactions between tumor cells and the cellular milieu, including immune cells, endothelial cells, and other tumor cells. Furthermore, recent years have witnessed considerable technological advances that have permitted in-depth sequence profiling of these small non-coding RNAs within EVs for their development as promising cancer biomarkers -particularly non-invasive, liquid biopsy markers in various cancers, including GI cancers. Herein, we summarize and discuss the roles of EV-associated miRNAs as they play a seminal role in GI cancer progression, as well as their promising translational and clinical potential as cancer biomarkers as we usher into the area of precision oncology.

lnc RNA LOC102163816 Promotes Proliferation of Porcine Follicular Granulosa Cells Via miR-455-3p/PTK2B/PI3K/AKT Pathway

The proliferation and differentiation of granulosa cells (GCs) is a crucial process in follicular development. However, the molecular regulatory mechanism of follicular proliferation and differentiation of GCs needs further research. Studies have reported that follicular fluid exosomes are involved in regulation of proliferation of GCs, but the specific mechanism is unclear. This study demonstrated that LOC102163816 is upregulated in porcine GCs treated with follicular fluid exosomes. Further study defined LOC102163816 to be a novel long noncoding RNA that is highly homologous to human metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and enriched in porcine follicular fluid exosomes. We have speculated that LOC102163816 might have a cell-proliferative effect similar to that of MALAT1. We found that overexpression of LOC102163816 promoted transition from the G1 phase to the S phase of the cell cycle, thereby promoting proliferation of GCs. To explore the specific mechanism underlying this promotion of proliferation, miRNA sequencing was performed after overexpression of LOC102163816. Our results showed that LOC102163816 sponged miR-455-3p, promoting expression of protein tyrosine kinase 2 beta (PTK2B), thereby activating the PI3K/AKT signaling pathway to regulate proliferation of porcine follicular GCs. These findings provide useful insights into follicular development.

Protective effect of oral stem cells extracellular vesicles on cardiomyocytes in hypoxia-reperfusion

Hypoxia signaling plays an important role in physiological and pathological conditions. Hypoxia in the heart tissue can produce different consequences depending on the duration of exposure to the hypoxic state. While acute hypoxic exposure leads to a reversible acclimatization in heart tissue with normal systemic oxygen supply, chronic hypoxia exacerbates cardiac dysfunction, leads to a destruction of the tissue. Extracellular vesicles (EVs) are small membrane vesicles that act as mediators of intercellular communication. EVs are secreted by different cell types and those produced by oral cavity-derived mesenchymal stem cells (MSCs), including human gingival MSCs (hGMSCs), have pro-angiogenic and anti-inflammatory effects and showed therapeutic role in tissue regeneration. The aim of the present work was to evaluate the potential protective and regenerative role of EVs produced by hGMSCs, in an in vitro model of hypoxia-conditioned HL-1 cardiomyocytes through the expression analysis of following inflammatory, oxidative stress, angiogenesis, cell survival and apoptotic markers: HIF-1α, P300, NFkB, CCL2, IL1B, IL6, NRF2, CASP-3, BAX and VEGF. Results showed that hGMSCs-derived EVs exerted protection HL-1 cardiomyocytes exposed to both pre and post hypoxic conditions. Moreover, modulation of CASP3 and BAX expression demonstrated that EVs reduced the apoptosis. The analysis of microRNAs in EVs derived from hGMSCs was performed to assess the epigenetic regulation of the presented markers. The following microRNAs: hsa-miR-138-5p, hsa-miR-17-5p, hsa-miR-18a-5p, hsa-miR-21-5p, hsa-miR-324-5p, hsa-miR-133a-3p, hsa-miR-150-5p, hsa-miR-199a-5p, hsa-miR-128-3p and hsa-miR-221-3p can directly or indirectly target the studied genes by determining their modulation obtained in our study. The data from this study suggested that EVs obtained from hGMSCs may be considered for the cell free treatment option in hypoxia-driven cardiac tissue dysfunction.

A New Paradigm in Spinal Cord Injury Therapy: from Cell-free Treatment to Engineering Modifications

Spinal cord injury (SCI) is an intractable and poorly prognostic neurological disease, and current treatments are still unable to cure it completely and avoid sequelae. Extracellular vesicles (EVs), as important carriers of intercellular communication and pharmacological effects, are considered to be the most promising candidates for SCI therapy because of their low toxicity and immunogenicity, their ability to encapsulate endogenous bioactive molecules (e.g., proteins, lipids, and nucleic acids), and their ability to cross the blood-brain/cerebrospinal barriers. However, poor targeting, low retention rate, and limited therapeutic efficacy of natural EVs have bottlenecked EVs-based SCI therapy. A new paradigm for SCI treatment will be provided by engineering modified EVs. Furthermore, our limited understanding of the role of EVs in SCI pathology hinders the rational design of novel EVbased therapeutic approaches. In this study, we review the pathophysiology after SCI, especially the multicellular EVs-mediated crosstalk; briefly describe the shift from cellular to cell-free therapies for SCI treatment; discuss and analyze the issues related to the route and dose of EVs administration; summarize and present the common strategies for EVs drug loading in the treatment of SCI and point out the shortcomings of these drug loading methods; finally, we analyze and highlight the feasibility and advantages of bio-scaffold-encapsulated EVs for SCI treatment, providing scalable insights into cell-free therapy for SCI.

Dual Role of Exosome in Neurodegenerative Diseases: A Review Study

INTRODUCTION

Extracellular vesicles (EVs) are one of the crucial means of intercellular communication, which takes many different forms. They are heterogeneous, secreted by a range of cell types, and can be generally classified into microvesicles and exosomes depending on their location and function. Exosomes are small EVs with diameters of about 30-150 nm and diverse cell sources.

METHODS

The MEDLINE/PubMed database was reviewed for papers written in English and publication dates of recent years, using the search string "Exosome" and "Neurodegenerative diseases."

RESULTS

The exosomes have attracted interest as a significant biomarker for a better understanding of disease development, gene silencing delivery, and alternatives to stem cell-based therapy because of their low-invasive therapeutic approach, repeatable distribution in the central nervous system (CNS), and high efficiency. Also, they are nanovesicles that carry various substances, which can have an impact on neural plasticity and cognitive functioning in both healthy and pathological circumstances. Therefore, exosomes are conceived as nanovesicles containing proteins, lipids, and nucleic acids. However, their composition varies considerably depending on the cells from which they are produced.

CONCLUSION

In the present review, we discuss several techniques for the isolation of exosomes from different cell sources. Furthermore, reviewing research on exosomes' possible functions as carriers of bioactive substances implicated in the etiology of neurodegenerative illnesses, we further examine them. We also analyze the preclinical and clinical research that shows exosomes to have therapeutic potential.

Cellular Uptake of Engineered Extracellular Vesicles: Biomechanisms, Engineered Strategies, and Disease Treatment

Extracellular vesicles (EVs), lipid-enclosed nanosized membrane vesicles, are regarded as new vehicles and therapeutic agents in intercellular communication. During internal circulation, if EVs are not effectively taken up by recipient cells, they will be cleared as "cellular waste" and unable to deliver therapeutic components. It can be seen that cells uptake EVs are the prerequisite premise for sharing intercellular biological information. However, natural EVs have a low rate of absorption by their recipient cells, off-target delivery, and rapid clearance from circulation, which seriously reduces the utilization rate. Affecting the uptake rate of EVs through engineering technologies is essential for therapeutic applications. Engineering strategies for customizing EV uptake can potentially overcome these limitations and enable desirable therapeutic uses of EVs. In this review, the mechanism and influencing factors of natural EV uptake will be described in detail. Targeting each EV uptake mechanism, the strategies of engineered EVs and their application in diseases will be emphatically discussed. Finally, the future challenges and perspectives of engineered EVs are presented multidimensionally.

Differentiation of Neurons, Astrocytes, Oligodendrocytes and Microglia From Human Induced Pluripotent Stem Cells to Form Neural Tissue-On-Chip: A Neuroinflammation Model to Evaluate the Therapeutic Potential of Extracellular Vesicles Derived from Mesenchymal Stem Cells

Advances in stem cell (SC) technology allow the generation of cellular models that recapitulate the histological, molecular and physiological properties of humanized in vitro three dimensional (3D) models, as well as production of cell-derived therapeutics such as extracellular vesicles (EVs). Improvements in organ-on-chip platforms and human induced pluripotent stem cells (hiPSCs) derived neural/glial cells provide unprecedented systems for studying 3D personalized neural tissue modeling with easy setup and fast output. Here, we highlight the key points in differentiation procedures for neurons, astrocytes, oligodendrocytes and microglia from single origin hiPSCs. Additionally, we present a well-defined humanized neural tissue-on-chip model composed of differentiated cells with the same genetic backgrounds, as well as the therapeutic potential of bone marrow mesenchymal stem cells (BMSCs)-derived extracellular vesicles to propose a novel treatment for neuroinflammation derived diseases. Around 100 nm CD9 + EVs promote a more anti-inflammatory and pro-remodeling of cell-cell interaction cytokine responses on tumor necrosis factor-α (TNF-α) induced neuroinflammation in neural tissue-on-chip model which is ideal for modeling authentic neural-glial patho-physiology.

A clinically relevant large-scale biomanufacturing workflow to produce natural killer cells and natural killer cell-derived extracellular vesicles for cancer immunotherapy

Natural killer cell-derived extracellular vesicles (NK-EVs) have shown promising potential as biotherapeutics for cancer due to their unique attributes as cytotoxic nanovesicles against cancer cells and immune-modulatory activity towards immune cells. However, a biomanufacturing workflow is needed to produce clinical-grade NK-EVs for pre-clinical and clinical applications. This study established a novel biomanufacturing workflow using a closed-loop hollow-fibre bioreactor to continuously produce NK-EVs from the clinically relevant NK92-MI cell line under serum-free, Xeno-free and feeder-free conditions following GMP-compliant conditions. The NK92 cells grown in the bioreactor for three continuous production lots resulted in large quantities of both NK cell and NK-EV biotherapeutics at the end of each production lot (over 109 viable cells and 1013 EVs), while retaining their cytotoxic payload (granzyme B and perforin), pro-inflammatory cytokine (interferon-gamma) content and cytotoxicity against the human leukemic cell line K562 with limited off-target toxicity against healthy human fibroblast cells. This scalable biomanufacturing workflow has the potential to facilitate the clinical translation of adoptive NK cell-based and NK-EV-based immunotherapies for cancer with GMP considerations.

Effects of treatment with stem cell-derived extracellular vesicles in preclinical rodent models of intrauterine adhesion: A meta-analysis

Background

Intrauterine adhesion (IUA) results from serious complications of intrauterine surgery or infection and mostly remains incurable. Small extracellular vesicles (sEVs) derived from mesenchymal stem cells (MSCs) have emerged as a potential new approach for the treatment of IUA; however, their impact is not fully understood. Here, we performed a meta-analysis summarizing the effects of sEVs on IUA in preclinical rodent models.

Methods

This meta-analysis included searches of PubMed, EMBASE, Cochrane, and the Web of Science databases from January 1, 1997, to April 1, 2022, to identify studies reporting the therapeutic effect of sEVs on rodent preclinical animal models of IUA. We compared improvements in endometrial thickness, endometrial gland number, fibrosis area, embryo number, vascular endothelial growth factor (VEGF), transforming growth factor β1 (TGFβ1), and leukemia inhibitory factor (LIF) levels after treatment.

Results

Our search included 100 citations, of which 7 met the inclusion criteria, representing 231 animals. Compared with that in the control group, the fibrosis area in the sEV-treated group was significantly reduced (standardized mean difference (SMD) = -6.87，95 % confidence interval (CI) = -9.67 to -4.07). The number of glands increased after the intervention (95 % CI, 3.72-7.68; P = 0.000). Endometrial thickness was significantly improved in the sEV-treated group (SMD = 2.57, 95 % CI, 1.62-3.52).

Conclusions

This meta-analysis is highlighting that sEV treatment can improve the area of endometrial fibrosis, as well as VEGF, and LIF level, in a mouse IUA model. This knowledge of these findings will provide new insights into future preclinical research.

mRNA as a medicine in nephrology: the future is now

The successful employment of messenger RNA (mRNA) as vaccine therapy for the prevention of COVID-19 infection has spotlighted the attention of scientific community onto the potential clinical application of these molecules as innovative and alternative therapeutic approaches in different fields of medicine. As therapy, mRNAs may be advantageous due to their unique biological properties of targeting almost any genetic component within the cell, many of which may be unreachable using other pharmacological/therapeutic approaches, and encoding any proteins and peptides without the need for their transport into the nuclei of the target cells. Additionally, these molecules may be rapidly designed/produced and clinically tested. Once the chemistry of the RNA and its delivery system are optimized, the cost of developing novel variants of these medications for new selected clinical disorders is significantly reduced. However, although potentially useful as new therapeutic weapons against several kidney diseases, the complex architecture of kidney and the inability of nanoparticles that accommodate oligonucleotides to cross the integral glomerular filtration barrier have largely decreased their potential employment in nephrology. However, in the next few years, the technical improvements in mRNA that increase translational efficiency, modulate innate and adaptive immunogenicity, and increase their delivery at the site of action will overcome these limitations. Therefore, this review has the scope of summarizing the key strengths of these RNA-based therapies and illustrating potential future directions and challenges of this promising technology for widespread therapeutic use in nephrology.

Can extracellular vesicles be considered as a potential frontier in the treatment of intervertebral disc disease?

As a global public health problem, low back pain (LBP) caused by intervertebral disc degeneration (IDD) seriously affects patients' quality of life. In addition, the prevalence of IDD tends to be younger, which brings a huge burden to individuals and society economically. Current treatments do not delay or reverse the progression of IDD. The emergence of biologic therapies has brought new hope for the treatment of IDD. Among them, extracellular vesicles (EVs), as nanoscale bioactive substances that mediate cellular communication, have now produced many surprising results in the research of the treatment of IDD. This article reviews the mechanisms and roles of EVs in delaying IDD and describes the prospects and challenges of EVs.

Hypoxic preconditioned MSCs-derived small extracellular vesicles for photoreceptor protection in retinal degeneration

Photoreceptor apoptosis is an important pathogenesis of retinal degeneration and a primary cause of vision loss with limited treatment methods. Mesenchymal stem/stromal cells-derived small extracellular vesicles (MSC-sEVs) have shown therapeutic value in various ocular disorders. Recent studies have revealed that hypoxic preconditioning can improve the effectiveness of MSC-sEVs in tissue regeneration. However, whether hypoxic preconditioned MSC-sEVs (Hyp-sEVs) exert superior effects on photoreceptor protection relative to normoxic conditioned MSC-sEVs (Nor-sEVs) remains unclear. Here, we reported that Hyp-sEVs further improved retinal structure, recovered retinal function, and suppressed photoreceptor apoptosis in N-methyl-N-nitrosourea (MNU)-induced mouse model compared with Nor-sEVs. Hyp-sEVs also exhibited enhanced anti-apoptotic roles in MNU-provoked 661 W cell injury in vitro. We then analyzed the protein profiles of Nor-sEVs and Hyp-sEVs by LC-MS/MS and found that growth-associated protein 43 (GAP43) was enriched in Hyp-sEVs. The knockdown of GAP43 abolished the retinal therapeutic effects of Hyp-sEVs. Mechanistically, hypoxic stimulation-induced hypoxia-inducible factor-1α (HIF-1α) activation was responsible for preventing tripartite motif-containing protein 25 (TRIM25)-mediated GAP43 ubiquitination and degradation, leading to the upregulation of GAP43 in Hyp-sEVs. Together, our findings uncover the efficacy and mechanism of Hyp-sEVs-based photoreceptor protection and highlight the potential of Hyp-sEVs as optimized therapeutics for retinal degeneration.

Strategies for Cartilage Repair in Osteoarthritis Based on Diverse Mesenchymal Stem Cells-Derived Extracellular Vesicles

Osteoarthritis (OA) causes disability and significant economic and social burden. Cartilage injury is one of the main pathological features of OA, and is often manifested by excessive chondrocyte death, inflammatory response, abnormal bone metabolism, imbalance of extracellular matrix (ECM) metabolism, and abnormal vascular or nerve growth. Regrettably, due to the avascular nature of cartilage, its capacity to repair is notably limited. Mesenchymal stem cells-derived extracellular vesicles (MSCs-EVs) play a pivotal role in intercellular communication, presenting promising potential not only as early diagnostic biomarkers in OA but also as efficacious therapeutic strategy. MSCs-EVs were confirmed to play a therapeutic role in the pathological process of cartilage injury mentioned above. This paper comprehensively provides the functions and mechanisms of MSCs-EVs in cartilage repair.

Exosome delivery to the testes for dmrt1 suppression: A powerful tool for sex-determining gene studies

Exosomes are endosome-derived extracellular vesicles about 100 nm in diameter. They are emerging as promising delivery platforms due to their advantages in biocompatibility and engineerability. However, research into and applications for engineered exosomes are still limited to a few areas of medicine in mammals. Here, we expanded the scope of their applications to sex-determining gene studies in early vertebrates. An integrated strategy for constructing the exosome-based delivery system was developed for efficient regulation of dmrt1, which is one of the most widely used sex-determining genes in metazoans. By combining classical methods in molecular biology and the latest technology in bioinformatics, isomiR-124a was identified as a dmrt1 inhibitor and was loaded into exosomes and a testis-targeting peptide was used to modify exosomal surface for efficient delivery. Results showed that isomiR-124a was efficiently delivered to the testes by engineered exosomes and revealed that dmrt1 played important roles in maintaining the regular structure and function of testis in juvenile fish. This is the first de novo development of an exosome-based delivery system applied in the study of sex-determining gene, which indicates an attractive prospect for the future applications of engineered exosomes in exploring more extensive biological conundrums.