Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

Hypoxia LUAD H1975 cell-derived exosomal miR-671-3p promotes angiogenesis via regulating KLF2-VEGFR2 axis

For solid tumors, hypoxia is associated with disease aggressiveness and poor outcomes. In addition to undergoing broad intracellular molecular and metabolic adaptations, hypoxic tumor cells extensively communicate with their microenvironments to facilitate conditions favorable for their survival, growth, and metastasis. This communication is mediated by diverse secretory factors, including exosomes (extracellular vesicles of endosomal origin). Exosomal cargo is altered considerably by hypoxia, with significant impacts on tumor-cell communication with both local and distant microenvironments. Exosomes released by cancer cells influence the tumor environment to accelerate metastasis. While tumor-derived exosomes have been identified as a major driver of premetastatic niche formation at distant sites, this mechanism in lung adenocarcinoma (LUAD) remains unclear. We found that miR-671-3p in exosomes derived from H1975 under hypoxic conditions target Krüppel-like factor 2 (KLF2) to regulate VEGFR2 expression in endothelial cells to promote angiogenesis. In addition, miR-671-3p is expressed at high levels in circulating exosomes isolated from patients with LUAD. Our study suggests that exosome miR-671-3p is involved in the formation of premetastatic niche and may serve as a blood-based biomarker for LUAD metastasis.

Proteomic Insights into Human Limbal Epithelial Progenitor-Derived Small Extracellular Vesicles

Limbal epithelial stem/progenitor cells (LEPC), supported by limbal mesenchymal stromal cells (LMSC) and limbal melanocytes (LM) within a specialized niche, are responsible for maintaining the corneal epithelium. Small extracellular vesicles (sEV) emerged as critical mediators of intercellular communication in various stem cell niches, yet their role in maintaining human limbal niche homeostasis remains poorly understood. In this study, tangential flow filtration and size exclusion chromatography were used to isolate sEV from LEPC-, LMSC- and LM-conditioned media. The isolated sEV from LEPC exhibited properties characteristic for sEV as confirmed by nanoparticle tracking analysis for size and concentration, by electron microscopy for morphology, and by western blot analysis of canonical EV markers including the cell-specific protein (cytokeratin 17/19). Quantitative and comparative proteomic profiling revealed distinct molecular signatures of LEPC-derived sEV, enriched in factors associated with keratinocyte development, extracellular matrix organization, and niche regulation. These findings suggest that LEPC-derived sEV may serve as important signaling mediators within the limbal niche microenvironment, though additional studies are needed to determine their specific functional roles in maintaining niche homeostasis.

Changes and application prospects of biomolecular materials in small extracellular vesicles (sEVs) after flavivirus infection

Small extracellular vesicles (sEVs), also known as exosomes, are membranous vesicles filled with various proteins and nucleic acids, serving as a communication vector between cells. Recent research has highlighted their role in viral diseases. This review synthesizes current understanding of viral sEVs and includes recent findings on sEVs infected with flaviviruses. It discusses the implications of viral sEVs research for advancing arbovirus sEVs research and anticipates the potential applications of sEVs in flavivirus infections.

Drug Resistance: The Role of Sphingolipid Metabolism

A significant challenge in cancer treatment is the rising problem of drug resistance that reduces the effectiveness of therapeutic strategies. Current knowledge shows that multiple mechanisms play a role in cancer drug resistance. Another mechanism that has gained attention is the alteration in sphingolipid trafficking and the dysregulation of its metabolism, which was reported to cause cancer-associated drug resistance. Sphingolipids are lipids containing sphingosine and have multiple roles, ranging from lipid raft formation, apoptosis, and cell signaling to immune cell trafficking. Recent studies show that in developing cancer cells, altered or dysregulated sphingolipids are associated with drug efflux and promote the survival of cancer cells by bypassing apoptosis. Upregulated levels of the glucosylceramide synthase (GCS), an enzyme that functions in sphingolipid metabolism, lead to the upregulated ABCB1 gene that induces drug efflux from the cancer cells. These bypass mechanisms make drugs that induce apoptosis in tumor cells ineffective. By highlighting the current findings, this review aims to provide a mechanism of drug resistance caused by the dysregulation of glucosylceramide synthase, sphingosine kinase, and acid ceramidase enzymes as possible therapeutic targets to enhance the effectiveness of the currently used chemotherapeutic agents.

Exosomal biomarkers: A novel frontier in the diagnosis of gastrointestinal cancers

Gastrointestinal (GI) cancers, which predominantly manifest in the stomach, colorectum, liver, esophagus, and pancreas, accounting for approximately 35% of global cancer-related mortality. The advent of liquid biopsy has introduced a pivotal diagnostic modality for the early identification of premalignant GI lesions and incipient cancers. This non-invasive technique not only facilitates prompt therapeutic intervention, but also serves as a critical adjunct in prognosticating the likelihood of tumor recurrence. The wealth of circulating exosomes present in body fluids is often enriched with proteins, lipids, microRNAs, and other RNAs derived from tumor cells. These specific cargo components are reflective of processes involved in GI tumorigenesis, tumor progression, and response to treatment. As such, they represent a group of promising biomarkers for aiding in the diagnosis of GI cancer. In this review, we delivered an exhaustive overview of the composition of exosomes and the pathways for cargo sorting within these vesicles. We laid out some of the clinical evidence that supported the utilization of exosomes as diagnostic biomarkers for GI cancers and discussed their potential for clinical application. Furthermore, we addressed the challenges encountered when harnessing exosomes as diagnostic and predictive instruments in the realm of GI cancers.

Understanding the complex role of exosomes in intestinal ischemia-reperfusion injury: from pathogenesis to protection

Extracellular vesicles, which are predominantly classified into ectosomes and exosomes, are released by all cells under both physiological conditions and in response to acquired pathological states. Exosomes demonstrate multifaceted functions: they regulate cellular homeostasis through the elimination of redundant or detrimental intracellular components, function as mediators in intercellular signaling pathways, and serve as potential vectors for both diagnostic and therapeutic applications. Intestinal ischemia-reperfusion injury (IRI), a prevalent form of tissue and organ injury in surgical settings, has been extensively investigated. Emerging evidence indicates a crucial relationship between exosomes and intestinal IRI, specifically regarding how exosomes derived from either intestinal tissue or distant organs can modulate the pathophysiological progression of intestinal IRI. This review systematically evaluates the mechanistic roles of exosomes in intestinal IRI and their involvement in post-intestinal IRI multiple organ dysfunction, aiming to establish a theoretical foundation for therapeutic interventions and future research directions.

FLT1-enriched extracellular vesicles induce a positive feedback loop between nasopharyngeal carcinoma cells and endothelial cells to promote angiogenesis and tumour metastasis

Distant metastasis is one of the main reasons for treatment failure in nasopharyngeal carcinoma (NPC) patients. Tumour angiogenesis is a key basis for the distant metastasis of NPC. However, the molecular mechanisms underlying the mutual interaction between endothelial and NPC cells in tumour angiogenesis and NPC metastasis are still unclear. Here, we found that extracellular vesicles (EVs) mediate intercellular communication between endothelial cells and NPC cells, thereby promoting NPC cell migration, invasion, colony formation, and angiogenesis. Further experiments indicated that EV-mediated information exchange between endothelial cells and NPC cells upregulated the expression of the vascular endothelial growth factor receptor FLT1 in both types of cells. Mechanistically, FLT1-enriched EVs promoted NPC metastasis through the PI3K/AKT pathway and increased tumour angiogenesis, tumour growth, and distant lung and liver metastasis of NPC in xenografted mice. This effect was achieved through the delivery and upregulation of FLT1 in both endothelial and NPC cells. Thus, our findings reveal that FLT1-enriched EVs induce a positive feedback loop between NPC cells and endothelial cells to promote tumour angiogenesis and tumour metastasis. These results increase our understanding of the intricate interplay between tumour angiogenesis and distant metastasis and have major implications for the diagnosis and management of NPC patients with increased levels of FLT1-enriched EVs.

Keratinocyte-derived extracellular vesicles induce macrophage polarization toward an M1-like phenotype

Multiple reports have shown an effect of keratinocyte-derived extracellular vesicles (EVs) on keratinocytes and other cell types. However, the contribution of keratinocyte-derived EVs under physiological and pathological conditions is not fully elucidated. Therefore, whether there is an effect of EVs on macrophages in cervical cancer (CC) is also unknown. Here, we evaluated the effect of tumor and non-tumor keratinocyte-derived EVs on the polarization of peripheral blood mononuclear cells (PBMCs)-derived macrophages and THP-1 cell line. Flow cytometric evaluation of macrophages cultured in the presence of keratinocyte-derived EVs mainly indicated an increase in classical activation markers CD80 and CD86 (M1 phenotype) and little or no modification of alternative activation markers (M2 phenotype). ELISA evaluation of macrophage supernatants revealed an increase in the secretion of proinflammatory cytokines such as IL-1β and IL-6. On the other hand, TGF-β was not significantly modified and only EVs derived from non-cancerous keratinocytes induced a significant increase in IL-10. The expression levels of transcripts associated with the M1 phenotype were also evaluated by qRT-PCR with similar results to ELISA for TGF-β and IL-10; but also an increase in the expression of HLA-DRα and TNF-α was observed, and no statistically significant changes in ARG1. The ROS production was also evaluated and this increase mainly in macrophages treated with CC keratinocytes-derived EVs. So, our results suggest that the uptake of EVs derived from released by non-tumor and cervical cancer keratinocytes promotes in macrophages their polarization to an M1-like phenotype.

Host-Pathogen Cellular Communication: The Role of Dynamin, Clathrin, and Macropinocytosis in the Uptake of Giardia-Derived Extracellular Vesicles

Giardia intestinalis, a protozoan causing giardiasis, disrupts gastrointestinal health through complex host-parasite interactions. This study explores the differential uptake mechanisms of extracellular vesicles (EVs) derived from Giardia (gEVs), host cells (hEVs), and the host-parasite interaction (intEVs) in intestinal Caco-2 cells. Results show that intEVs are internalized more rapidly than gEVs and hEVs, underscoring their pivotal role in pathogenesis. To delineate uptake pathways, various endocytosis inhibitors were applied, and clathrin-mediated endocytosis inhibition using monodansylcadaverine (MDC) significantly reduced intEV and gEV uptake, confirming the role of clathrin-mediated endocytosis (CME). The use of dynasore, a dynamin inhibitor, strongly reduced the internalization of all EV types, demonstrating that uptake is dynamin-dependent. In contrast, methyl-β-cyclodextrin (MβCD), which disrupts lipid rafts and caveolae-mediated pathways, had no effect on EV uptake, indicating that caveolae are not involved in this process. Furthermore, inhibition of Na+/H+ exchange and phosphoinositide 3-kinase activity, both essential for macropinocytosis, also led to a significant reduction in intEV internalization. These findings strongly support that gEVs are internalized primarily through a dynamin- and clathrin-dependent pathway, independent of caveolae and lipid rafts, but modulated by tyrosine kinase signaling and macropinocytosis. These insights into selective and comprehensive inhibition pathways offer promising therapeutic targets to mitigate giardiasis.

Segatella copri Outer-Membrane Vesicles Are Internalized by Human Macrophages and Promote a Pro-Inflammatory Profile

Increased abundance of Segatella copri (S. copri) within the gut microbiota is associated with systemic inflammatory diseases, including rheumatoid arthritis. Although outer-membrane vesicles (OMVs) of Gram-negative bacteria are important players in microbiota-host communication, the effect of S. copri-derived OMVs on immune cells is unknown. Macrophages engulf and eliminate foreign material and are conditioned by environmental signals to promote either homeostasis or inflammation. Thus, we aimed to explore the impact of S. copri-OMVs on human macrophages in vitro, employing THP-1 and monocyte-derived macrophage models. The uptake of DiO-labeled S. copri-OMVs into macrophages was monitored by confocal microscopy and flow cytometry. Furthermore, the effect of S. copri and S. copri-OMVs on the phenotype and cytokine secretion of naïve (M0), pro-inflammatory (M1), and anti-inflammatory (M2) macrophages was analyzed by flow cytometry and ELISA, respectively. We show that S. copri-OMVs enter human macrophages through macropinocytosis and clathrin-dependent mechanisms. S. copri-OMVs, but not the parental bacterium, induced a dose-dependent increase in the expression of M1-related surface markers in M0 and M2 macrophages and activated the secretion of large amounts of pro-inflammatory cytokines in M1 macrophages. These results highlight an important role of S. copri-OMVs in promoting pro-inflammatory macrophage responses, which might contribute to systemic inflammatory diseases.

Characterization of size distribution and markers for mosquito extracellular vesicles

Extracellular vesicles (EVs) are non-replicative, cell-derived membranous structures secreted by potentially all eukaryotic cells, playing a crucial role in intercellular communication. The study of EVs requires approaches and tools, which have predominantly been developed for mammalian models. Here, we undertook a multimodal characterization of mosquito EVs to provide a technical and knowledge foundation for their study. First, using a cell line model from Aedes aegypti and applying multiple analytical technologies (i.e., NTA, TEM, cryo-EM, and AFM), we observed that mosquito EVs range from 20 to 500 nm in diameter and that a majority are smaller than 100 nm. Second, we showed that smaller EVs are secreted in mosquito saliva. Third, we evaluated the capacity of differential centrifugation and size exclusion chromatography to separate mosquito EVs, revealing the strengths and weaknesses of each technology. Finally, we identified a mosquito homolog of CD63 as an extravesicular marker and the mosquito syntenin as a putative luminal marker. Overall, our results promote the development of tools and approaches for the study of mosquito EVs.

Small extracellular vesicles (sEVs) in pancreatic cancer progression and diagnosis

Pancreatic cancer is one of the most aggressive malignancies with poor prognostic outcomes, necessitating the exploration of novel biomarkers and therapeutic targets for early detection and effective treatment. Small extracellular vesicles (sEVs) secreted by cells, have gained considerable attention in cancer research due to their role in intercellular communication and their potential as non-invasive biomarkers. This review focuses on the role of sEVs in the progression of pancreatic cancer and their application as biomarkers. We delve into the biogenesis, composition, and functional implications of sEVs in pancreatic tumor biology, emphasizing their involvement in processes such as tumor growth, metastasis, immune modulation, and chemotherapy resistance. In addition, we discuss the challenges in isolating and characterizing sEVs. The review also highlights recent advances in the utilization of sEV-derived biomarkers for the early diagnosis, prognosis, and monitoring of pancreatic cancer. By synthesizing the latest findings, we aim to underscore the significance of sEVs in pancreatic cancer and their potential to revolutionize patient management through improved diagnostics and targeted therapies.

Extracellular vesicles in multiple myeloma: pathogenesis and therapeutic application

Multiple myeloma (MM), characterised by the clonal proliferation of plasma cells in the bone marrow, is the second most common haematological malignancy worldwide. Although there is now an impressive artillery of therapeutics to tackle this condition, resistance remains a prevalent issue. The bone marrow microenvironment performs a crucial role in supporting MM pathogenesis and promoting the development of therapeutic resistance. Extracellular vesicles (EVs), small vesicles that carry bioactive molecules, are a key component of cell-to-cell communication within the bone marrow microenvironment. In this review, we summarise the contribution of EVs to disease progression and anticancer treatment resistance and discuss the potential therapeutic applications of EVs in MM.

The roles of extracellular vesicles in mental disorders: information carriers, biomarkers, therapeutic agents

Mental disorders are complex conditions that encompass various symptoms and types, affecting approximately 1 in 8 people globally. They place a significant burden on both families and society as a whole. So far, the etiology of mental disorders remains poorly understood, making diagnosis and treatment particularly challenging. Extracellular vesicles (EVs) are nanoscale particles produced by cells and released into the extracellular space. They contain bioactive molecules including nucleotides, proteins, lipids, and metabolites, which can mediate intercellular communication and are involved in various physiological and pathological processes. Recent studies have shown that EVs are closely linked to mental disorders like schizophrenia, major depressive disorder, and bipolar disorder, playing a key role in their development, diagnosis, prognosis, and treatment. Therefore, based on recent research findings, this paper aims to describe the roles of EVs in mental disorders and summarize their potential applications in diagnosis and treatment, providing new ideas for the future clinical transformation and application of EVs.

Multi-Omics Analysis of the Immune Effect of the Engineered Exosome Drug Delivery System in Inducing Macrophage Apoptosis

Background: In this study, exosomes were engineered with anti-CD47 antibody and loaded with rifapentine to improve their ability to target macrophages for drug delivery. Methods: Exosomes from RAW264.7 cell supernatant were extracted by differential centrifugation, antibody-modified, and drug-loaded ultrasonically. After co-culturing with macrophages, transcriptomics and proteomics screened differentially expressed genes and proteins. Western Blot identified macrophage polarization, ELISA detected inflammatory indicators, and an apoptosis kit was used for fluorescence staining. Results: Transcriptome sequencing showed that 406 genes in the macrophages changed significantly, with pathways like TNF and NF-κB. Proteomics identified 7478 proteins, 433 with significant differences. Western Blot indicated M1 polarization. Fluorescence staining showed apoptosis in the antiMExo-RIF group. Conclusions: The study provides multi-omics evidence of the immune mechanism of the engineered exosome drug delivery system in inducing macrophage apoptosis, revealing potential molecular mechanisms and the great potential use of engineered exosomes in treating macrophage-related diseases.

Causal relationship between breast cancer and acute myeloid leukemia based on two-sample bidirectional Mendelian randomization and transcriptome overlap analysis

BACKGROUND

Breast cancer is the most prevalent malignancy and the leading cause of cancer-related deaths among women worldwide. Several case reports have shown that some breast cancer patients subsequently develop acute myeloid leukemia (AML) within a short period. However, the causal relationship and pathogenic mechanisms between breast cancer and AML remain incompletely understood.

METHODS

Mendelian randomization (MR) analyses were conducted to explore the bidirectional causal relationships between breast cancer and AML. Additionally, we applied the Bayesian Weighted Mendelian Randomization (BWMR) approach to validate the results of the MR analysis. Subsequently, we utilized RNA-seq data from various sources to explore the potential molecular signaling pathways between breast cancer and AML.

RESULTS

Both IVW method and BWMR approach demonstrated that data from three distinct sources consistently indicated breast cancer as a risk factor for AML, with all sources showing statistically significant results (all P < 0.05, Odds Ratios [ORs] > 1). Bioinformatic analyses suggested that extracellular vesicle functions and p53 signaling pathway may mediate molecular links between breast cancer and AML. Using machine learning, we identified 8 genes with high diagnostic efficacy for predicting the occurrence of AML in breast cancer patients.

CONCLUSIONS

MR analyses indicated a causal relationship between breast cancer and AML. Additionally, transcriptome analysis offered a theoretical basis for understanding the potential mechanisms and therapeutic targets of AML in breast cancer patients.

Hetero Sandwich Immunoassay as Tool to Probe the Composition of the Extracellular Vesicles Membranes: The Case Study of L1CAM Localization

Lateral flow immunoassays (LFIAs) are widely used for point-of-care diagnostic devices due to their simplicity, low cost, and rapid results. In this work, we demonstrate that a heterosandwich design LFIA can be an effective tool for verifying the presence of different proteins on the same particles. As a case study, we address a recent controversy regarding the presence of the protein L1CAM on the extracellular vesicles (EVs). EVs are crucial for cell communication and may serve as valuable disease biomarkers, including for neurodegenerative disorders. EVs from neuronal cells can cross the blood-brain barrier and be selectively isolated from plasma. Although L1CAM has been suggested as a marker for neuron-derived EVs, recent studies report that L1CAM exists as a cleaved soluble protein in plasma, not associated with EVs. We propose a heterosandwich LFIA to detect and quantify L1CAM and a confirmed EV marker, tetraspanin CD63 or CD9, on the same EV. This assay, together with several control experiments on EVs isolated from plasma by size exclusion chromatography (SEC), demonstrates that although most L1CAM in plasma is present as soluble cleaved proteins, 13% of the EVs are strongly associated with this protein. This evidence is confirmed by dynamic light scattering measurements, showing a significant size increase of gold nanoparticles conjugated with L1CAM antibodies when exposed to EVs but not to cleaved soluble L1CAM. Our results validate the selective immune-isolation of L1CAM-EVs, resolving the controversy by confirming that L1CAM is indeed associated with a significant fraction of EVs despite the presence of its soluble form in plasma.

Plasma Microvesicles May Contribute to Muscle Damage in the mdx Mouse Model of Duchenne Muscular Dystrophy

Extracellular vesicles (EVs) are cell-derived lipid-bound vesicles divided into apoptotic bodies, microvesicles (MVs), and exosomes based on their biogenesis, release pathway, size, content, and functions. EVs are intercellular mediators that significantly affect muscle diseases such as Duchenne muscular dystrophy (DMD). DMD is a fatal X-linked disorder caused by mutations in the dystrophin gene, leading to muscle degeneration. Mdx mice are the most commonly used model to study the disease, and in this study, we phenotypically characterized plasma MVs from mdx mice by flow cytometry. Furthermore, we assessed the ability of plasma MVs to modulate muscle inflammation, damage, and/or regeneration by intramuscular injection of MVs from mdx mice into mdx or DBA/2 mice as a control. In both mouse lineages, platelets and erythrocytes were the primary sources of MVs, and CD3+ CD4+ MVs were observed only in mdx mice. We also observed that plasma MVs from mdx mice induced muscle damage in mdx mice but not in DBA/2 mice, while plasma MVs from DBA/2 mice did not induce muscle damage in either mouse lineage. These results indicate that plasma MVs from mdx are potentially pathogenic. However, this condition also depends on the muscular tissue status, which must be responsive due to active inflammatory or regenerative responses.

Exosomal PD-L1 in non-small cell lung Cancer: Implications for immune evasion and resistance to immunotherapy

Exosomes, characterized by their bilayer lipid structure, are crucial in mediating intercellular signaling and contributing to various physiological processes. Tumor cells produce distinct exosomes facilitating cancer progression, angiogenesis, and metastasis by conveying signaling molecules. A notable feature of these tumor-derived exosomes is the presence of programmed death-ligand 1 (PD-L1) on their surface. The PD-L1/programmed cell death receptor-1 (PD-1) signaling axis serves as a critical immune checkpoint, enabling tumors to evade immune detection and antitumor activity. The advancement of immunotherapy targeting the PD-1/PD-L1 pathway has significantly impacted the treatment landscape for non-small cell lung cancer (NSCLC). Despite its promise, evidence indicates that many patients experience limited responses or develop resistance to PD-1/PD-L1 inhibitors. Recent studies suggest that exosomal PD-L1 contributes to this resistance by modulating immune responses and tumor adaptability. This study reviews the PD-1/PD-L1 pathway's characteristics, current clinical findings on PD-L1 inhibitors in NSCLC, and exosome-specific attributes, with a particular focus on exosomal PD-L1. Furthermore, it examines the growing body of research investigating the role of exosomal PD-L1 in cancer progression and response to immunotherapy, underscoring its potential as a target for overcoming resistance in NSCLC treatment.

Human neural stem cell-derived exosomes activate PINK1/Parkin pathway to protect against oxidative stress-induced neuronal injury in ischemic stroke

BACKGROUND

Mitochondria play a critical role in oxidative stress (OS)-induced neuronal injury during ischemic stroke (IS), making them promising therapeutic targets. Mounting evidence underscores the extraordinary therapeutic promise of exosomes derived from human neural stem cells (hNSCs) in the management of central nervous system (CNS) diseases. Nonetheless, the precise mechanisms by which these exosomes target mitochondria to ameliorate the effects of IS remain only partially elucidated. This study investigates the protective effects of hNSC derived exosomes (hNSC-Exos) on neuronal damage.

METHODS

Using a rat model of middle cerebral artery occlusion (MCAO) in vivo and OS-induced HT22 cells in vitro. Firstly, our research group independently isolated human neural stem cells (hNSCs) and subsequently prepared hNSC-Exos. In vivo, MCAO rats were restored to blood flow perfusion to simulate ischemia-reperfusion injury, and hNSC-Exos were injected through stereotaxic injection into the brain. Subsequently, the protective effects of hNSC-Exos on MCAO rats were evaluated, including histological studies, behavioral assessments. In vivo, H2O2 was used in HT22 cells to simulate the OS environment in MCAO, and then its protective effects on HT22 were evaluated by co-culturing with hNSC-Exos, including immunofluorescence staining, western blotting (WB), quantitative real time PCR (qRT-PCR). In the process of exploring specific mechanisms, we utilized RNA sequencing (RNA-seq) to detect the potential induction of mitophagy in OS-induced HT22 cells. Afterwards, we employed a series of mitochondrial function assessments and autophagy related detection techniques, including measuring mitochondrial membrane potential, reactive oxygen species (ROS) levels, transmission electron microscopy (TEM) imaging, monodansylcadaverine (MDC) staining, and mCherry-GFP-LC3B staining. In addition, we further investigated the regulatory pathway of hNSC-Exos by using autophagy inhibitor mdivi-1 and knocking out PTEN induced kinase 1 (PINK1) in HT22 cells.

RESULTS

Administration of hNSC-Exos significantly ameliorated brain tissue damage and enhanced behavioral outcomes in MCAO rats. This treatment led to a reduction in brain tissue apoptosis and facilitated the normalization of impaired neurogenesis and neuroplasticity. Notably, the application of hNSC-Exos in vitro resulted in an upregulation of mitophagy in HT22 cells, thereby remedying mitochondrial dysfunction. We demonstrate that hNSC-Exos activate mitophagy via the PINK1/Parkin pathway, improving mitochondrial function and reducing neuronal apoptosis.

CONCLUSIONS

These findings suggest that hNSC-Exos alleviate OS-induced neuronal damage by regulating the PINK1/Parkin pathway. These reveals a novel role of stem cell-derived mitochondrial therapy in promoting neuroprotection and suggest their potential as a therapeutic approach for OS-associated CNS diseases, including IS.

Newly-diagnosed rheumatoid arthritis patients have elevated levels of plasma extracellular vesicles with protein cargo altered towards inflammatory processes

Extracellular vesicles (EVs) are implicated in rheumatoid arthritis (RA) but have mainly been assessed in RA patients taking disease modifying anti-rheumatic drugs. EVs are nanoparticles important in cell-cell communication and their molecular cargo are biomarker candidates. We characterized the protein profiles of EVs from blood plasma from newly diagnosed, treatment naïve RA patients (N = 32) and compared them to healthy controls (N = 20), by size exclusion chromatography-based EV enrichment coupled with high-resolution quantitative proteomics. The RA patients had higher EV concentration and larger EVs than controls. A total of 682 EV proteins were reliably quantified, and the overall profiles were distinctly different between patients and controls. Specifically, 26 proteins were significantly upregulated and 31 downregulated in RA patients, with several proteins acting in inflammatory networks and with immunologically important upstream regulators. The RA associated EVs appear, based on the tissue expression of their cargo proteins, to originate mainly from hepatocytes or immune cells, like neutrophils. Interestingly, the strongest RA associated EV proteins were inflammatory molecules, like SAA1 and S100A9, already suggested as biomarkers in RA. Furthermore, the RA associated EV proteins were generally not correlated with total serum protein levels, stressing the importance of EV transport of inflammatory proteins in RA pathogenesis.

Extracellular vesicles: innovative cell-free solutions for wound repair

Chronic non-healing wounds are often associated with conditions such as diabetes and peripheral vascular disease, pose significant medical and socioeconomic challenges. Cell-based therapies have shown promise in promoting wound healing but have major drawbacks such as immunogenicity and tumor formation. As a result, recent research has shifted to the potential of extracellular vesicles (EVs) derived from these cells. EVs are nanosized lipid bilayer vesicles, naturally produced by all cell types, which facilitate intercellular communication and carry bioactive molecules, offering advantages such as low immunogenicity, negligible toxicity and the potential to be re-engineered. Recent evidence recognizes that during wound healing EVs are released from a wide range of cells including immune cells, skin cells, epithelial cells and platelets and they actively participate in wound repair. This review comprehensively summarizes the latest research on the function of EVs from endogenous cell types during the different phases of wound healing, thereby presenting interesting therapeutic targets. Additionally, it gives a critical overview of the current status of mesenchymal stem cell-derived EVs in wound treatment highlighting their tremendous therapeutic potential as a non-cellular of-the-shelf alternative in wound care.

The role of plant-derived extracellular vesicles in ameliorating chronic diseases

Plant-derived extracellular vesicles (PDEVs) have been shown to have a promising role in treating chronic illnesses. Plants secrete these vesicles containing bioactive chemicals such as proteins, lipids, nucleic acids, and small metabolites. Because of their unique structure, PDEVs affect many biological processes, which makes them an ideal candidate for treating the complex pathophysiology of chronic diseases. Recent studies have shown that PDEVs have anti-inflammatory and antioxidant properties. Extracellular vesicles (EVs) possess diverse therapeutic potential, including anti-inflammatory, antioxidant, and regenerative properties. By regulating immune responses, scavenging free radicals, and promoting tissue repair, EVs can address various chronic diseases such as cardiovascular disorders, neurological conditions, skin diseases, and inflammatory ailments. In preclinical models, PDEVs have been demonstrated to improve heart function and minimize the size of myocardial infarctions. In neurodegenerative illnesses, they can pass through the blood-brain barrier and deliver neuroprotective medicines to the brain. Furthermore, PDEVs have shown promise in enhancing insulin sensitivity and lowering hyperglycemia in diabetic animals. In this review article, we attempt to explain the diverse therapeutic potential of PDEVs in ameliorating chronic diseases.

Research progress of extracellular vesicles derived from mesenchymal stem cells in the treatment of neurodegenerative diseases

As the world's population ages, neurodegenerative diseases are becoming more widely acknowledged as serious global health and socioeconomic issues. Although many resources have been devoted to the research of these illnesses, little progress has been made in the creation of novel diagnostic and therapeutic approaches. Extracellular vesicles (EVs) are released by all cell types and contain proteins, microRNAs, mRNAs, and other biologically active molecules. EVs play an important role in intercellular communication as well as in the regulation of neuroinflammation. Determining the mechanisms by which EVs contribute to the pathogenesis of neurodegenerative diseases will aid in the development of new therapeutic approaches and diagnostic tools. Mesenchymal stem cells (MSCs) have been shown in studies to control immunological responses, promote the growth of new brain connections, promote the production of blood vessels, and heal damaged tissues. There is growing evidence that MSCs' ability to treat patients is mostly due to the neurotrophic compounds they secrete through EVs. Since their tiny size allows them to pass through biological barriers and reach injured parts of the central nervous system, MSC-derived extracellular vesicles (MSC-EVs) retain many of the therapeutic qualities of their parent MSCs. This review discusses the role of EVs in neurodegenerative diseases and highlights the potential of MSC-EVs in the treatment of neurodegenerative diseases. The paper also examines the challenges that still need to be overcome and the prospects for using MSC-EVs to treat neurodegenerative illnesses.

Functional maturation of preterm intestinal epithelium through CFTR activation

Preterm birth disrupts intestinal epithelial maturation, impairing digestive and absorptive functions. This study integrates analysis of single-cell RNA sequencing datasets, spanning fetal to adult stages, with human preterm intestinal models derived from the ileal tissue of preterm infants. We investigate the potential of extracellular vesicles (EVs) derived from human Wharton's jelly mesenchymal stem cells to promote intestinal maturation. Distinct enterocyte differentiation trajectories are identified during the transition from immature to mature stages of human intestinal development. EV treatment, particularly with the EV39 line, significantly upregulates maturation-specific gene expression related to enterocyte function. Gene set enrichment analysis reveals an enrichment of TGFβ1 signaling pathways, and proteomic analysis identifies TGFβ1 and FGF2 as key mediators of EV39's effects. These treatments enhance cell proliferation, epithelial barrier integrity, and fatty acid uptake, primarily through CFTR-dependent mechanisms-unique to human preterm models, not observed in mouse intestinal organoids. This highlights the translational potential of EV39 and CFTR activation in promoting the functional maturation of the premature human intestine.

The endoplasmic reticulum as a cradle for virus and extracellular vesicle secretion

Extracellular vesicles (EVs) are small membranous carriers of protein, lipid, and nucleic acid cargoes and play a key role in intercellular communication. Recent work has revealed the previously under-recognized participation of endoplasmic reticulum (ER)-associated proteins (ERAPs) during EV secretion, using pathways reminiscent of viral replication and secretion. Here, we present highlights of the literature involving ER/ERAPs in EV biogenesis and propose mechanistic parallels with ERAPs exploited during viral infections. We propose that ERAPs play an active role in the release of EVs and viral particles, and we present views on whether viruses hijack or enhance pre-existing ERAP-dependent secretory machineries or whether they repurpose ERAPs to create new secretory pathways.

Circulating Vesicular-bound HLA-G as Noninvasive Predictive Biomarker of CLAD After Lung Transplantation

BACKGROUND

Circulating extracellular vesicles (EVs) have shown promising results as noninvasive biomarkers for predicting disease outcomes in solid organ transplantation. Because in situ graft cell expression of the tolerogenic molecule HLA-G is associated with acceptance after lung transplantation (LTx), we hypothesized that plasma EV-bound HLA-G (HLA-G EV ) levels could predict chronic lung allograft dysfunction (CLAD) development.

METHODS

We analyzed 78 LTx recipients from the Cohort-for-Lung-Transplantation cohort, all in a stable (STA) state within the first year post-LTx. At 3 y, 41 patients remained STA, and 37 had CLAD (bronchiolitis obliterans syndrome, BOS, [n = 32] or restrictive allograft syndrome [n = 5]). HLA-G EV plasma levels were measured at month 6 (M6) and M12 in 78 patients. CLAD occurrence and graft failure at 3 y post-LTx were assessed according to early HLA-G EV plasma levels.

RESULTS

In patients with subsequent BOS, (1) HLA-G EV levels at M12 were significantly lower than those in STA patients ( P  = 0.013) and (2) also significantly lower than their previous levels at M6 ( P  = 0.04).A lower incidence of CLAD and BOS and higher graft survival at 3 y were observed in patients with high HLA-G EV plasma levels at M12 (high versus low HLA-G EVs patients [cutoff 21.3 ng/mL]: freedom from CLAD, P  = 0.002; freedom from BOS, P  < 0.001; and graft survival, P  = 0.04, [log-rank]). Furthermore, in multivariate analyses, low HLA-G EV levels at M12 were independently associated with a subsequent risk of CLAD, BOS, and graft failure at 3 y ( P  = 0.015, P  = 0.036, and P  = 0.026, respectively [Cox models]).

CONCLUSIONS

This exploratory study suggests the potential of EV-bound HLA-G plasma levels as a liquid biopsy in predicting CLAD/BOS onset and subsequent graft failure.

Dual Role of Exosomes in Parkinson's Disease: Adenine Exerts a Beneficial Effect

AIMS

Developing validated treatments for Parkinson's disease (PD) remains a priority for clinicians and researchers. The lack of viable therapies may stem from an incomplete understanding of PD pathogenesis and inadequate therapeutic candidates. The production and transmission of exosomes are gaining recognition in the pathogenesis of neurodegenerative diseases. However, how exosomes affect the pathophysiology of PD has not been well elucidated.

METHODS

Here, we investigated the effect of exosomes secreted by rats that were treated with saline or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP) in treating healthy or PD model mice, and we evaluated the efficacy of peripheral and intracranial administration of adenine, which is an exosomal metabolite identified through widely targeted metabolomics.

RESULTS

We found that exosomes derived from the blood of healthy rats alleviated motor dysfunction, dopaminergic neuron loss in the substantia nigra pars compacta and striatum, oxidative injury, and neuroinflammation. Conversely, exosomes from the blood of PD model rats reproduced the behavioral phenotype and pathology of PD in healthy mice. Additionally, peripheral and intracranial administration of adenine ameliorated the motor coordination disorder and dopaminergic neuron loss, and maintained the homeostasis of oxidative stress and neuroinflammation by activating cAMP/PKA signaling in PD.

CONCLUSION

Together, these findings shed light on the mechanism by which exosomes participate in the pathophysiology of PD by transmitting the metabolite adenine and providing potential therapeutic strategies.

Use of the Malaria Protein VAR2CSA for the Detection of Small Extracellular Vesicles to Diagnose Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) poses a significant challenge for early diagnosis due to the lack of sensitive and specific biomarkers. This encouraged us to explore the diagnostic value of cancer-derived small extracellular vesicles (sEVs) as early detection biomarkers. We previously showed that the recombinant malaria protein VAR2CSA (rVAR2) selectively binds to oncofetal chondroitin sulfate (ofCS) on the surfaces of cancer cells, which might be useful for identifying cancer-derived sEVs. Indeed, flow cytometry revealed strong ofCS expression in PDAC cell-derived sEVs, as evidenced by the presence of mutant KRAS, a common genetic alteration in PDAC. Plasma from PDAC patients showed significantly higher ofCS+ sEV levels compared to healthy donors and patients with benign gastrointestinal diseases. ROC analysis for ofCS+ sEVs revealed an AUC of 0.9049 for the detection of all-stage and 0.9222 for early-stage PDAC. Notably, mutant KRAS was also detected in these patient-derived sEVs. Most intriguingly, combining ofCS+ sEVs and CA19-9 resulted in an AUC of 0.9707 for the detection of early PDAC. Our study demonstrates that rVAR2 is suitable for detecting ofCS+ cancer-derived sEVs in plasma, thereby providing high efficiency for identifying PDAC patients among a diverse population. These findings suggest that rVAR2-based sEV detection could serve as a powerful diagnostic tool to improve patient survival through early detection.

Microscopic messengers: Extracellular vesicles shaping gastrointestinal health and disease

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.

Application of stem cell-derived exosomes in anterior segment eye diseases: A comprehensive update review

Mesenchymal stem cell (MSC) therapy has emerged as a promising approach for addressing various eye-related conditions. Yet, its clinical application faces challenges due to issues such as limited biocompatibility and difficulties in effectively delivering treatment to specific ocular tissues. Recent studies have shifted attention towards MSC-derived exosomes, which share similar regenerative, reparative, and immunomodulatory capabilities with their origin cells. This review delves into the latest research on the use of MSC-derived exosomes for treating anterior segment diseases of the eye. It explores the exosomes' composition, biological functions, and the methods used for their isolation, as well as their roles in disease progression, diagnosis, and therapy. The review critically assesses the therapeutic advantages and mechanisms of action of MSC-derived exosomes in treating conditions like dry eye disease, Sjogren's syndrome, keratoconus, corneal lesions, and corneal allograft rejection. Additionally, it discusses the obstacles and future prospects of employing MSC-derived exosomes as innovative therapies for anterior segment eye diseases. This comprehensive overview underscores the significant potential of MSC-derived exosomes in transforming the treatment paradigm for anterior segment eye disorders, while also highlighting the necessity for further research to enhance their clinical application.

Neural Stem Cell Extracellular Vesicles Carrying YBX1 Inhibited Neuronal Pyroptosis Through Increasing m6A-modified GPR30 Stability and Expression in Ischemic Stroke

Neural stem cell-derived extracellular vesicles (NSC-derived EVs) alleviated ischemic stroke (IS) by suppressing the activation of nucleotide-binding domain leucine-rich repeats family protein 3 (NLRP3) inflammasome and neuronal pyroptosis. However, the specific mechanism needs further investigation. qRT-qPCR, Western blotting, and immunofluorescence detected related gene expression. Immunofluorescent analyzed the expression of Ki-67, βIII-Tubulin (Tuj1), and GFAP. Lactate dehydrogenase (LDH) release and IL-1β and IL-18 levels were analyzed by LDH and ELISA kits. TTC staining evaluated the infarction of brain tissues. Flow cytometric analysis measured caspase-1 activity. M6A methylated RNA immunoprecipitation PCR (MeRIP-PCR) measured methylation levels of G protein-coupled receptor 30 (GPR30). RIP and Co-IP analyzed the interactions of Y box binding protein (YBX1)/GPR30, YBX1/IGF2BP1 and NLRP3/speckle-type POZ protein (SPOP), as well as the ubiquitination levels of NLRP3. NSC-derived EVs inhibited the ischemia-reperfusion (I/R) injury of rats and the neuronal pyroptosis induced by oxygen-glucose deprivation/reoxygenation (OGD/R). Knockdown of EVs carrying YBX1 or GPR30 silencing abolished these inhibiting effects. GPR30 mRNA and IGF2BP1 protein were enriched by YBX1 antibody. YBX1 enhanced the stability of m6A-modified GPR30 by interacting with IGF2BP1 and thus promoting GPR30 expression. Knockdown of IGF2BP1 suppressed the binding between YBX1 and GPR30 mRNA. GPR30 promoted NLRP3 ubiquitination by interacting with SPOP. EVs carrying YBX1 could reduce the infarction of brain tissues and inhibit neuronal pyroptosis in rats with I/R injury. NSC-derived EVs carrying YBX1 increased the stability of m6A-modified GPR30 by interacting with IGF2BP1; the upregulation of GPR30 inhibited the activation of NLRP3 inflammasome through promoting NLRP3 ubiquitination by SPOP, ultimately suppressing the neuronal pyroptosis in IS.

Lymph node-targeted delivery of Lonicera japonica thunb. polysaccharides for enhancing antitumor immunotherapy

Dendritic cells (DCs) are crucial for the initiation and regulation of innate and adaptive immunity. Their maturity and infiltration in the tumor largely determine the efficiency of antigen presentation, the CTL responses, and the prognosis of tumors. However, the application of common immunoregulatory plant polysaccharides to DCs in vivo still represents major challenges due to the off-target effect and short biological lifespan. Lonicera japonica Thunb. polysaccharides (LJP) were found to exert benign immunoregulatory ability, but the effectiveness of utilizing LJP alone is unsatisfactory. As a result, we innovatively encapsulated LJP in into the exosomes derived from mouse bone mesenchymal stem cells (BMSCs) to form a DC-activated inducer (LJP-exosome). LJP-exosomes possessed a profound ability to target lymph nodes and the co-stimulatory capability of DCs compared with the application of LJP alone. Adequate results have shown that DCs primed by LJP-exosomes enhanced the tumor-reactive CD8+ T cell responses, leading to prophylactic tumor inhibition in an immunologically ignorant tumor model. The study proposed offers a promising strategy for enhancing the immune activation efficacy of extracted polysaccharides of traditional Chinese medicine by building the patients' immunity, thus consolidating the overall prognosis.

Comparative Analysis of the Therapeutic Potential of Extracellular Vesicles Secreted by Aged and Young Bone Marrow-Derived Mesenchymal Stem Cells in Osteoarthritis Pathogenesis

Osteoarthritis (OA), a joint disease, burdens global healthcare due to aging and obesity. Recent studies show that extracellular vesicles (EVs) from bone marrow-derived mesenchymal stem cells (BMSCs) contribute to joint homeostasis and OA management. However, the impact of donor age on BMSC-derived EV efficacy remains underexplored. In this study, we investigated EV efficacy from young BMSCs (2-month-old) in mitigating OA, contrasting them with EVs from aged BMSCs (27-month-old). The study used destabilisation of the medial meniscus (DMM) surgery on mouse knee joints to induce accelerated OA. Cartilage degeneration markers and senescence markers' expression levels were investigated in response to EV treatment. The therapeutic impact of EVs on chondrocytes under inflammatory responses was also evaluated. Despite having similar morphologies, EVs from young BMSCs markedly decreased senescence and improved chondroprotection by activating the PTEN pathway while simultaneously suppressing the upregulation of the PI3K/AKT pathways, proving to be more effective than those from older BMSCs in vitro. Furthermore, intraperitoneal injections of EVs from young donors significantly mitigated OA progression by preserving cartilage and reducing synovitis in a surgical OA model using DMM in mice. These findings highlight that donor age as a critical determinant in the therapeutic potential of BMSC-derived EVs for clinical use in OA treatment.

Exosomes in Facial Plastic Surgery

Exosomes have emerged as a promising therapeutic frontier in facial plastic surgery. Preclinical studies have demonstrated their ability to modulate wound healing, skin rejuvenation, hair growth, and nerve regeneration. Early clinical evidence suggests potential benefits in enhancing recovery after laser resurfacing, treating acne scars, and promoting hair growth. Despite their potential, there are currently no exosome products that are FDA-approved for medical use, and they should be considered experimental until receiving regulatory approval and robust clinical validation. As research advances, exosomes may offer valuable tools for facial plastic surgeons to improve patient outcomes and expand regenerative medicine applications in facial aesthetics and reconstruction.

Red cell microparticles produced using high-pressure extrusion enhance both primary and secondary hemostasis

BACKGROUND

Current therapies to treat excessive bleeding are associated with significant complications, which may outweigh their benefits. Red blood cell-derived microparticles (RMPs) are a promising hemostatic agent. Previous studies demonstrated that they reduce bleeding in animal models, correct coagulation defects in patient blood, and have an excellent safety profile. However, their exact mechanism of action is not known. We investigated the potential role of RMPs on primary and secondary hemostasis.

METHODS

To evaluate the effects of RMPs, prepared using high-pressure extrusion, on primary hemostasis, we employed platelet aggregometry with platelet inhibitors, eptifibatide, and ticagrelor, with and without RMPs. To evaluate their effects on secondary hemostasis, we employed thromboelastography with plasma deficient in factors VII, VIII, IX, XI, and XII with and without RMPs.

RESULTS

We found that RMPs significantly increased collagen-induced platelet aggregation. However, there were no significant differences with and without RMP in the presence of the platelet inhibitors, indicating that RMPs may work through these receptors, either directly or indirectly. For secondary hemostasis, RMPs significantly decreased clotting times for plasma deficient in factors VII, VIII, IX, and XI but not in XII.

CONCLUSIONS

Our results indicate that RMPs enhance primary hemostasis and both pathways of secondary hemostasis.

Extracellular particles: emerging insights into central nervous system diseases

Extracellular particles (EPs), including extracellular vesicles (EVs) and non-vesicular extracellular particles (NVEPs), are multimolecular biomaterials released by cells that play a crucial role in intercellular communication. Recently, new subtypes of EPs associated with central nervous system (CNS), such as exophers and supermeres have been identified. These EPs provide new perspectives for understanding the pathological progression of CNS disorders and confer potential diagnostic value for liquid biopsies in neurodegenerative diseases (NDs). Moreover, EPs have emerged as promising drug delivery vehicles and targeted platforms for CNS-specific therapies. In this review, we delineate the landscape of EP subtypes and their roles in the pathophysiology of CNS diseases. We also review the recent advances of EP-based diagnosis in NDs and highlight the importance of analytical platforms with single-particle resolution in the exploitation of potential biomarkers. Furthermore, we summarize the application of engineered EVs in the treatment of CNS diseases and outline the underexplored potential of NVEPs as novel therapeutic agents.

Extracellular vesicles and the tumour microenvironment

Extracellular vesicles (EVs), tiny packages of information released by cells, are well established as being involved in unwanted cell-to-cell communication in cancer. EVs from cancer cells have been associated with the spread of drug resistance, immune suppression, and metastasis. Additional to cancer cells, the tumour microenvironment (TME) involves many cell types -including immune cells, fibroblasts, and endothelial cells, each of which has a potential role in how tumours grow, spread, and respond (or otherwise) to therapy. This review collates and distils research developments regarding the role of EVs in multi-way communication between cells in the TME. Further research including tailored clinical studies are now warranted to determine how best to prevent this extensive adverse communication occurring and/or how best to exploit it for biomarker discovery and as a therapeutic approach, in the interest of patients and also for economic benefit.

Comparing the therapeutic influence of bone marrow Mesenchymal stem cells versus its derived exosomes against diabetic hepatopathy in rats

Diabetes mellitus (DM) is a chronic widespread metabolic disorder, involving a high blood glucose level which causes multiple serious complications including liver, kidney, brain and peripheral nerves damage. Due to the undesirable side effects of the anti-diabetic drugs, the current studies directed to use stem cells and exosomes to overcome the limitations of traditional therapy. We aimed to compare the antidiabetic effect of Bone marrow mesenchymal stem cells (BMMSCs) and its derived exosomes against diabetic hepatopathy induced by streptozotocin (STZ) in albino rats. Our study was conducted on 28 male albino rats divided into 4 groups {control negative non diabetic group, control positive diabetic group, exosomes treated group received (5 × 109 particle/rat) through tail vein twice per week for one month} and Stem cell treated group received (107) BMMSCs through tail vein twice per week for one month. Hepatic structure together with blood glucose level, liver function enzymes were assayed in addition to a lipid profile tests, oxidative stress, and gene expression. Both treated groups by exosomes and stem cells expressed significantly low levels of fasting blood glucose, liver function parameters (ALT, AST, ALP), lipid profile tests (cholesterol and triglycerides), lipid peroxidation index (MDA), with substantial reduction in IL-1β expression compared to diabetic group. Significantly downregulating the VEGF and elevation of eNOS genes and GSH which suggest the effective role provided by BMMSCs and its derived exosomes for treatment of diabetic hepatopathy. Although, the results of both groups showed near average outcomes, the exosome treated group significantly enhanced liver function enzymes and triglyceride, cholesterol level compared to stem cells treated group. These findings were reinforced by the histopathological and immunohistochemistry examination. The latter showed slight but non-significant improvements in VEGF, eNOS, and IL-1β expression. These minor differences together with practical advantages of exosomes make it preferable over BMMSCs in treatment of diabetic hepatopathy.

Proteomics of urinary exosomes for discovering novel non-invasive biomarkers of acute myocardial infarction patients

BACKGROUND

Patients with acute myocardial infarction (AMI) can be identified by myocardial enzymes in peripheral blood, but no protein markers have been found in urinary exosomes derived from AMI patients.

METHODS

In the present study, a comprehensive proteomics analysis of urinary exosomes derived from patients with AMI was performed. Firstly, we employed the outstanding separation method known as EXODUS to isolate urinary exosomes from AMI patients and healthy controls. Then, we characterized urinary exosomes by nanoparticle tracking analysis (NTA), western blotting and transmission electron microscopy (TEM). After that, we identified the protein components of exosomes through label-free proteomics and conducted bioinformatics analysis.

RESULT

High-quality exosomes were obtained through separation using EXODUS, which could be demonstrated by NTA, Western blotting and TEM. NTA analysis showed that partilce amount in AMI patients was significantly higher than healthy controls. The equal-volume Western blotting experiment indicated that the expression level of classic exosomal markers Alix, heat shock protein90 (HSP90), CD63 and TSG101 (Tumor susceptibility gene101) in AMI patents was obviously stronger than healthy subjects. We first described the protein profiles of urinary exosomes in AMI patients through proteomics. In this study, We have identified 3194 proteins, among which a total of 30 differential proteins were detected between the urinary exosomes of AMI patients and healthy controls. We investigated F2 and OLR1 among identified exosomal proteins significantly elevated in AMI group, whereas F3 and APCS dysregulated in AMI development.

CONCLUSIONS

F2, F3, OLR1 and APCS are able to distinguish individuals between the AMI group and the healthy controls, and the protein panel represent a novel prospective non-invasive biomarkers for the diagnostic process of acute myocardial infarction.

Stress-induced extracellular vesicles: insight into their altered proteomic composition and probable physiological role in cancer

EVs (extracellular vesicles) are phospholipid bilayer vesicles that can be released by both prokaryotic and eukaryotic cells in normal as well as altered physiological conditions. These vesicles also termed as signalosomes, possess a distinctive cargo comprising nucleic acids, proteins, lipids, and metabolites, enabling them to play a pivotal role in both local and long-distance intercellular communication. The composition, origin, and release of EVs can be influenced by different physiological conditions and a variety of stress factors, consequently affecting the contents carried within these vesicles. Therefore, identifying the modified contents of EVs can provide valuable insights into their functional role in stress-triggered communication. Particularly, this is important when EVs released from tumor microenvironment are investigated for their role in the development and dissemination of cancer. This review article emphasizes the importance of differential EV shedding and altered proteomic content in response to reduced oxygen concentration, altered levels of glucose and glutamine, pH variations, oxidative stress and Ca2+ ion concertation and it is subsequent effects on the behavior of recipient cells.

Extracellular Vesicles Released From Skeletal Muscle Post-Chronic Contractile Activity Increase Mitochondrial Biogenesis in Recipient Myoblasts

The effect of chronic contractile activity (CCA) on the biophysical properties and functional activity of skeletal muscle extracellular vesicles (Skm-EVs) is poorly understood due to challenges in distinguishing Skm-EVs originating from exercising muscle in vivo. To address this, myoblasts were differentiated into myotubes, and electrically paced (3 h/day, 4 days @ 14 V). CCA evoked an increase in mitochondrial biogenesis in stimulated versus non-stimulated (CON) myotubes as expected. EVs were isolated from conditioned media (CM) from control and stimulated myotubes using differential ultracentrifugation (dUC) and characterised biophysically using tunable resistive pulse sensing (TRPS, Exoid), TEM and western blotting. TEM images confirmed isolated round-shaped vesicles of about 30-150 nm with an intact lipid bilayer. EVs ranged from 98 to 138 nm in diameter, and the mean size was not altered by CCA. Zeta potential and total EV protein yield remained unchanged between groups, and total EV secretion increased after 4 days of CCA. Concomitant analysis of EVs after each day of CCA also demonstrated a progressive increase in CCA-EV concentration, whilst size and zeta potential remained unaltered, and EV protein yield increased in both CON-EVs and CCA groups. CCA-EVs were enriched with small-EVs versus CON-EVs, concomitant with higher expression of small-EV markers CD81, Tsg101 and HSP70. In whole cell lysates, CD63 and ApoA1 were reduced with CCA in myotubes, whereas CD81, Tsg101, Flotillin-1 and HSP70 levels remained unchanged. To evaluate the functional effect of EVs secreted post-CCA, we treated C2C12 myoblasts with all EVs isolated from CON or CCA myotubes after each day of stimulation, and measured cell count, cell viability, protein yield and mitochondrial biogenesis in recipient cells. There was no effect on cell count, viability and protein yield. Myoblasts treated with CCA-EVs exhibited increased mitochondrial biogenesis as indicated by enhanced MitoTracker Red staining, cytochrome c oxidase (COX) activity and protein expression of electron transport chain subunit, CIV-MTCO1. Further, CCA-EV treatment enhanced maximal oxygen consumption rates (OCR) in a dose-dependent manner, and ATP production in treated myoblasts. This increase in maximal OCR was abrogated when CCA-EVs pre-treated with proteinase K were co-cultured with myoblasts, indicating the pro-metabolic effect was likely mediated by transmembrane or peripheral membrane proteins in CCA-EVs. Our data highlight the novel effect of Skm-EVs isolated post-CCA in mediating pro-metabolic effects in recipient cells and thereby transmitting the effects associated with traditional exercise. Further investigation to interrogate the underlying mechanisms involved in downstream cellular metabolic adaptations is warranted.

Unravelling Plasma Extracellular Vesicle Diversity With Optimised Spectral Flow Cytometry

Extracellular vesicles (EVs) are crucial for intercellular communication and are found in various biological fluids. The identification and immunophenotyping of such small particles continue to pose significant challenges. Here, we have developed a workflow for the optimisation of a next-generation panel for in-depth immunophenotyping of circulating plasma EVs using spectral flow cytometry. Our data collection followed a multistep optimisation phase for both instrument setup and 21-colour panel design, thus maximising fluorescent signal recovery. This spectral approach enabled the identification of novel EV subpopulations. Indeed, besides common EVs released by erythrocytes, platelets, leukocytes and endothelial cells, we observed rare and poorly known EV subsets carrying antigens related to cell activation or exhaustion. Notably, the unsupervised data analysis of major EV subsets revealed subpopulations expressing up to five surface antigens simultaneously. However, the majority of EVs expressed only a single surface antigen, suggesting they may not fully represent the phenotype of their parent cells. This is likely due to the small surface area or the biogenesis of EVs rather than antibody steric hindrance. Finally, we tested our workflow by analysing the plasma EV landscape in a cohort of systemic lupus erythematosus (SLE) patients. Interestingly, we observed a significant increase in CD54+ EVs, supporting the notion of elevated circulating ICAM under SLE conditions. To our knowledge, these are the first data highlighting the importance of a spectral flow cytometry approach in deciphering the heterogeneity of plasma EVs paving the way for the routine use of a high-dimensional immunophenotyping in EV research.

Nanoscopic Profiling of Small Extracellular Vesicles via High-Speed Atomic Force Microscopy (HS-AFM) Videography

Small extracellular vesicles (sEVs), which carry lipids, proteins and RNAs from their parent cells, serve as biomarkers for specific cell types and biological states. These vesicles, including exosomes and microvesicles, facilitate intercellular communication by transferring cellular components between cells. Current methods, such as ultracentrifugation and Tim-4 affinity method, yield high-purity sEVs. However, despite their small size, purified sEVs remain heterogeneous due to their varied intracellular origins. In this technical note, we used high-speed atomic force microscopy (HS-AFM) in conjunction with exosome markers (IgGCD63 and IgGCD81) to explore the intracellular origins of sEVs at single-sEV resolution. Our results first revealed the nanotopology of HEK293T-derived sEVs under physiological conditions. Larger sEVs (diameter > 100 nm) exhibited greater height fluctuations compared to smaller sEVs (diameter ≤ 100 nm). Next, we found that mouse-origin IgGCD63, and rabbit-origin IgGcontrol and IgGCD81, exhibited the iconic 'Y' conformation, and similar structural dynamics properties. Last, exosome marker antibodies predominantly co-localised with sEVd ≤ 100 nm but not with sEVd > 100 nm, demonstrating the CD63-CD81-enriched sEV and CD63-CD81-depleted sEV subpopulations. In summary, we demonstrate that nanoscopic profiling of surface exosome markers on sEVs using HS-AFM is feasible for characterising distinct sEV subpopulations in a heterogeneous sEV mixture.

Genetically modified extracellular vesicles loaded with activated gasdermin D potentially inhibit prostate-specific membrane antigen-positive prostate carcinoma growth and enhance immunotherapy

Prostate cancer (PCa) is associated with poor immunogenicity and lymphocytic infiltration, and immunotherapy effective against PCa remains unavailable. Pyroptosis, a novel immunotherapeutic modality for cancer, promotes systemic immune responses leading to immunogenic cell death in solid tumors. This paper describes the preparation and analysis of PSMAscFv-EVN-GSDMD; this genetically engineered recombinant extracellular vesicle (EV) expresses a single-chain variable antibody fragment (scFv) with high affinity for prostate-specific membrane antigen (PSMA) on their surfaces and is loaded with the N-terminal domain of gasdermin D (GSDMD). Both in vitro and in vivo, PSMAscFv-EVN-GSDMD effectively targeted PSMA-positive PCa cells and induced pyroptosis through the carrier properties of EVs and the specificity of PSMAscFv. In the 22RV1 and PSMA-transfected RM-1-inoculated PCa mouse models, PSMAscFv-EVN-GSDMD efficiently inhibited tumor growth and promoted tumor immune responses. In conclusion, PSMAscFv-EVN-GSDMD can convert the immunosuppressive "cold" tumor microenvironment of PCa into an immunogenic "hot" tumor microenvironment.

Exosome-derived hsa-miR-200c-3p, hsa-miR-25-3p and hsa-miR-301a-3p as potential biomarkers and therapeutic targets for restoration of PTEN expression in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is an aggressive kidney cancer subtype with limited biomarkers and therapeutic options. Thus, the present study aimed to evaluate the biomarker and therapeutic potential of Phosphatase and Tensin Homologue (PTEN)-regulating microRNAs (miRNAs) in 2D and 3D ccRCC models. Extracellular vesicles (EVs) from four renal cell lines were characterized, and selected miRNAs (hsa-miR-200c-3p, hsa-miR-25-3p, and hsa-miR-301a-3p) were quantified in cells and EVs. PTEN mRNA levels were measured intracellularly. 786-O cells were transfected with miRNA inhibitors in both models and effects on miRNA and PTEN expression were assessed alongside phenotypic alterations. The expression of target miRNAs increased with ccRCC cell aggressiveness, both intracellularly and in EVs, while PTEN mRNA expression decreased. Combined inhibition of these miRNAs significantly increased PTEN expression, reducing tumor cell proliferation and migration in 2D models and decreasing spheroid size and metabolic capacity in 3D models. These miRNAs show potential as biomarkers for monitoring disease aggressiveness and as therapeutic targets in ccRCC, potentially leading to more effective and personalized treatment approaches for ccRCC patients.

High-throughput capture and in situ protein analysis of extracellular vesicles by chemical probe-based array

Extracellular vesicles (EVs) are small particles with phospholipid bilayers that carry a diverse range of cargoes including nucleic acids, proteins and metabolites. EVs have important roles in various cellular processes and are increasingly recognized for their ubiquitous role in cell-cell communications and potential applications in therapeutics and diagnostics. Although many methods have been developed for the characterization and measurement of EVs, analyzing them from biofluids remains a challenge with regard to throughput and sensitivity. Recently, we introduced an approach to facilitate high-throughput analysis of EVs from trace amounts of sample. In this method, an amphiphile-dendrimer supramolecular probe (ADSP) is coated onto a nitrocellulose membrane for array-based capture and to enable an in situ immunoblotting assay. Here, we describe the protocol for our array-based method of EV profiling. We describe an enhanced version of the method that incorporates an automated printing workstation, ensuring high throughput and reproducibility. We further demonstrate the use of our array to profile specific glycosylations on the EV surface using click chemistry of an azide group introduced by metabolic labeling. In this protocol, the synthesis of ADSP and the fabrication of ADSP nitrocellulose membrane array can be completed on the same day. EVs are efficiently captured from biological or clinical samples through a 30-min incubation, followed by an immunoblotting assay within a 3-h window, thus providing a high-throughput platform for EV isolation and in situ targeted analysis of EV proteins and their modifications.

Direct delivery of immune modulators to tumour-infiltrating lymphocytes using engineered extracellular vesicles

Extracellular vesicles (EVs) are important mediators of cell-cell communication, including immune regulation. Despite the recent development of several EV-based cancer immunotherapies, their clinical efficacy remains limited. Here, we created antigen-presenting EVs to express peptide-major histocompatibility complex (pMHC) class I, costimulatory molecule and IL-2. This enabled the selective delivery of multiple immune modulators to antigen-specific CD8+ T cells, promoting their expansion in vivo without severe adverse effects. Notably, antigen-presenting EVs accumulated in the tumour microenvironment, increasing IFN-γ+ CD8+ T cell and decreasing exhausted CD8+ T cell numbers, suggesting that antigen-presenting EVs transformed the 'cold' tumour microenvironment into a 'hot' one. Combination therapy with antigen-presenting EVs and anti-PD-1 demonstrated enhanced anticancer immunity against established tumours. We successfully engineered humanized antigen-presenting EVs, which selectively stimulated tumour antigen-specific CD8+ T cells. In conclusion, engineering EVs to co-express multiple immunomodulators represents a promising method for cancer immunotherapy.

Embryo-Induced Changes in the Protein Profile of Bovine Oviductal Extracellular Vesicles

The study of early maternal-embryonic cross-talk remains one of the most challenging topics in reproductive biology. Understanding the physiological mechanisms involved in the interactions between the maternal reproductive tract and the developing embryo is essential for enhancing bovine reproductive efficiency. This complex communication starts within the oviduct, where the modulation of biological processes important for ensuring embryo quality is partially facilitated through extracellular vesicles (EVs). Utilizing a combination of in vivo and in vitro models this study had three main objectives: 1) to examine the protein cargo of EVs isolated from the oviductal fluid (OF) of cyclic and pregnant heifers to understand their role in maternal-embryonic communication in vivo; 2) to characterize the protein profile of EVs in conditioned medium (CM) resulting from the culture of oviductal explants alone (Exp) or in the presence of 8- to 16-cell stage embryos (Exp + Emb); and 3) to compare the protein cargo of EVs from Exp with EVs from cyclic heifers and EVs from Exp + Emb with EVs from pregnant heifers. Proteins were considered "identified" if detected in at least three out of five replicates and considered "exclusive" if detected in at least three out of five replicates within one group but absent in all samples of other groups. We identified 659 and 1476 proteins in the OF-EVs of cyclic and pregnant heifers, respectively. Among these, 644 proteins were identified in OF-EVs from both cyclic and pregnant heifers, and 40 proteins were exclusive to OF-EVs from the pregnant group. Within the 644 proteins identified in both groups, 31 were identified as differently abundant proteins (DAPs). In pregnant heifers, DAPs were mainly related to genome activation, DNA repair, embryonic cell differentiation, migration, and immune tolerance. In vitro, we identified 841 proteins in the CM-EVs from Exp alone, 613 from Exp + Emb, and 111 in the CM-EVs from Emb alone. In the qualitative analysis between the three in vitro groups, 81 proteins were identified in all groups, 452 were common to Exp and Exp + Emb, 17 were common to Exp and Emb, 5 were common to Exp + Emb and Emb, 4 were unique to Exp, 6 were unique to Exp + Emb, and none were unique to Emb. Proteins identified when there is an interaction between the oviduct and the embryo in vitro, corresponding to the Exp + Emb group, were associated with immune tolerance, structural activity, binding, and cytoskeletal regulation. In vivo and in vitro EVs exhibit distinct qualitative and quantitative protein contents, both when comparing EVs produced in the absence of an embryo (Cyclic and Exp) and those that have undergone embryo-oviduct interaction (Pregnant and Exp + Emb). The observed changes in the protein cargo of EVs due to maternal-embryonic communication in vivo and in vitro suggest that the interaction between the embryo and the maternal milieu initiates within the oviduct and is potentially facilitated by EVs and their protein contents.

Intranasal Delivery of Brain-Derived Neurotrophic Factor (BDNF)-Loaded Small Extracellular Vesicles for Treating Acute Spinal Cord Injury in Rats and Monkeys

Besides surgical decompression, neuroprotection and neuroinflammation reduction are critical for acute spinal cord injury (SCI). In this study, we prepared small extracellular vesicles (sEVs) from immortalised mesenchymal stem cells overexpressing brain-derived neurotrophic factor (BDNF) and evaluated whether intranasal administration of BDNF-sEVs is a therapeutic option for acute SCI. In cultured neurons, BDNF loading enhanced neurite outgrowth promoted by sEVs. After intranasal administration, mCherry-labelled sEVs were transported to the injured spinal cords of rats and monkeys and mainly taken up by neurons. In acute SCI rats, intranasal administration of sEVs and BDNF-sEVs reduced glial responses and proinflammatory cytokine production, enhanced neuronal survival and angiogenesis in the lesion, promoted injured axon rewiring, delayed lumbar spinal motoneuron atrophy below the lesion, and improved functional performance. The rats receiving BDNF-sEV treatment showed improved neural repair and functional recovery compared to those with sEV treatment. Intranasal administration of BDNF-sEVs, but not of sEVs, increased BDNF levels and phosphorylation of downstream signals in the rat-injured spinal cord samples, indicating activation of the BDNF/TrkB signalling pathway. In acute SCI monkeys, intranasal administration of BDNF-sEVs was further confirmed to inhibit glial reactivities and proinflammatory cytokine release, increasing BDNF levels in the cerebrospinal fluid, enhancing neural network rewiring of injured spinal cords and neuronal activities of the brain, and improving functional performances in behavioural tests and electrophysiological recordings. In conclusion, BDNF-sEVs play a combinatory therapeutic role of sEVs and BDNF, and intranasal administration of BDNF-sEVs is a potential option for the clinical treatment of acute SCI.