Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches

TNF-Stimulated Gene-6, Part of Extracellular Vesicles in Adipose Tissue-Derived Mesenchymal Stem Cell Concentrated Conditioned Medium, Affects Microglial Activity

Identifying the specific bioactive molecules produced by mesenchymal stem cells (MSCs) and the signaling pathways and cell types upon which they act is critical to developing MSC-based therapeutics for inflammatory diseases with high unmet needs. Our study aimed to investigate the impact of extracellular vesicle (EV)-derived TNF-Stimulated Gene-6 (TSG-6, from adipose tissue-derived mesenchymal stem cell concentrated conditioned medium, ASC-CCM or TSG-6 overexpression in ASC using ORF expression-ready clone) on microglia and its potential anti-inflammatory effects. EV but not non-vesicular secretome prepared by ultracentrifugation confirmed the expression of TSG-6 exclusively in the small EV (sEV) fraction. sEV ranged from 50-150 nm as determined by Zetasizer, demonstrated bilipid membrane evidenced by transmission electron microscopy, expressed positive exosomal (e.g. CD63) markers, and were endocytosed by BV2 cells confirmed by DiI fluorescently labeled exosomes. BV2 microglia cultured under serum-free conditions stimulated with TLR4 agonists (LPS and IFNγ) for 12 h in the presence of p-ASC-EV (sEV derived from ASC after cytokine stimulation) and TSG-6-ORF-EV significantly reduced nitrite release (p < 0.001), phagocytic activity (p < 0.001) and reduced CD44 expression (p < 0.05). CD44 knockdown in BV2 cells ablated TSG-6-ORF-EV mediated nitrite release, IL1β downregulation, and phagocytosis with TLR4 agonists. Our results revealed that under cytokine stimulation, the EV portion of ASC-CCM becomes enriched with TSG-6. Overexpressing TSG-6 in ASC leads to an increased concentration of TSG-6 in sEVs. This enriched EV fraction, containing TSG-6, regulates microglial dynamics through a feedback loop with CD44. EV-associated TSG-6 can influence immune cell behavior and signaling, mitigating excessive inflammation or immune dysfunction.

Proteomic profiling of small extracellular vesicles from bovine nucleus pulposus cells

Small extracellular vesicles (small EV) are a conserved means of communication across the domains of life and lately gained more interest in mammalian non-cancerous work as non-cellular, biological therapeutic with encouraging results in recent studies of chronic degenerative diseases. The nucleus pulposus (NP) is the avascular and aneural center of an intervertebral disc (IVD), home to unique niche conditions and affected in IVD degeneration. We investigated autologous and mesenchymal stem cell (MSC) small EVs for their potential to contribute to cell and tissue homeostasis in the NP niche via mass spectrometric proteome and functional enrichment analysis using adult and fetal donors. We compared these findings to published small EV databases and MSC small EV data. We propose several mechanisms associated with NP small EVs: Membrane receptor trafficking to modify signal responses promoting niche homeostasis; Redox and energy homeostasis via metabolic enzymes delivery; Cell homeostasis via proteasome delivery and immunomodulation beyond an association with a serum protein corona. The proteome signature of small EVs generated by NP parent cells is similar to previously published small EV data, yet with a focus on supplementing anaerobic metabolism and redox balance while contributing to the maintenance of an aneural and avascular microniche.

Persistent Stimulation of Human Mesenchymal Stem/Stromal Cells with TNF-α and IFN-γ Affects the Release of Large Extracellular Vesicles with Immunoregulatory Phenotype

Mesenchymal stem/stromal cells (MSCs) possess immunoregulatory capacity, which is enhanced in an inflammatory environment. Participation of extracellular vesicles (EVs) in this function is proposed, as they can transport various immunoregulatory molecules. However, the impact of the inflammatory microenvironment on the load of the different types of EVs released by these cells is not fully known. Therefore, this work analyzes in detail the temporal effect of IFN-γ, alone or in combination with TNF-α (TNF-α + IFN-γ), on the cargo of immunoregulatory molecules (programmed cell death ligand 1 [PD-L1], CD73, and intercellular adhesion molecule 1 [ICAM-1]) in large extracellular vesicles (L-EVs) released by human bone marrow mesenchymal stem cells (BM-MSCs). The presence of these molecules on the surface of L-EVs was determined by flow cytometry. Our results demonstrate that exposing BM-MSCs to TNF-α + IFN-γ for 24 h increases the percentage of PD-L1+ and CD73+ L-EVs. However, if this stimulus persists, the release of L-EVs with an immunoregulatory phenotype (PD-L1+, CD73+, and PD-L1+CD73+) decreases. The impact of pro-inflammatory cytokines on the transport of ICAM-1 by L-EVs is late, since up to 72 h of treatment with IFN-γ or TNF-α + IFN-γ, the percentage of ICAM-1+ L-EVs increases. In contrast, stimulation with IFN-γ for 72 h favors the release of CD73high and ICAM-1high L-EVs, but this effect also decreases in the presence of TNF-α. Our study generates novel knowledge about the impact of the inflammatory microenvironment on the cargo composition of L-EVs released by BM-MSCs and demonstrates, for the first time, that the prolonged presence of TNF-α reduces the cargo of immunoregulatory molecules in these structures.

Extracellular vesicles in age-related diseases: disease pathogenesis, intervention, and biomarker

Aging is a multifactorial biological process characterized by the irreversible accumulation of molecular damage, leading to an increased risk of age-related diseases. With the global prominent rise in aging populations, elucidating the mechanisms underlying the aging process and developing strategies to combat age-related diseases have become a pressing priority. Extracellular vesicles (EVs) have gained significant attention due to their role in intercellular communication. EVs are known for their ability to deliver biocargoes, such as miRNA, proteins, and lipids, implicating their involvement in disease pathogenesis and intervention. In this review article, we explore the dual role of EVs in age-related diseases: contributing to the pathogenesis of diseases by transferring deleterious molecules, while also offering therapeutic ability by transferring beneficial molecules. We also highlight the application of EVs as biomarkers for early diagnosis of age-related diseases, paving the way for early intervention and precision medicine. Additionally, we discuss how analysing the composition of EVs cargo can provide insights into disease progression. Finally, we address the challenges and future perspectives of EV-based-therapy in clinical translation, including standardization of EVs isolation methods and improving cargo specificity.

Development of human targeted extracellular vesicles loaded with shRNA minicircles to prevent parkinsonian pathology

BACKGROUND

Neurological disorders are the second leading cause of death and the leading cause of disability in the world. Thus, the development of novel disease-modifying strategies is clearly warranted. We have previously developed a therapeutic approach using mouse targeted rabies virus glycoprotein (RVG) extracellular vesicles (EVs) to deliver minicircles (MCs) expressing shRNA (shRNA-MCs) to induce long-term α-synuclein down-regulation. Although the previous therapy successfully reduced the pathology, the clinical translation was extremely unlikely since they were mouse extracellular vesicles.

METHODS

To overcome this limitation, we developed a source of human RVG-EVs compatible with a personalized therapy using immature dendritic cells. Human peripheral blood monocytes were differentiated in vitro into immature dendritic cells, which were transfected to express the RVG peptide. RVG-EVs containing shRNA-MCs, loaded by electroporation, were injected intravenously in the α-synuclein performed fibril (PFF) mouse model. Level of α-synuclein, phosphorylated α-synuclein aggregates, dopaminergic neurons and motor function were evaluated 90 days after the treatment. To confirm that EVs derived from patients were suitable as a vehicle, proteomic analysis of EVs derived from control, initial and advanced Parkinson's disease was performed.

RESULTS

The shRNA-MCs could be successfully loaded into human RVG-EVs and downregulate α-synuclein in SH-SY5Y cells. Intravenous injection of the shRNA-MC-loaded RVG-EVs induced long-term downregulation of α-synuclein mRNA expression and protein level, decreased α-synuclein aggregates, prevented dopaminergic cell death and ameliorated motor impairment in the α-synuclein PFF mouse model. Moreover, we confirmed that the EVs from PD patients are suitable as a personalized therapeutic vehicle.

CONCLUSION

Our study confirmed the therapeutic potential of shRNA-MCs delivered by human RVG-EVs for long-term treatment of neurodegenerative diseases. These results pave the way for clinical use of this approach.

Screening scaffold proteins for improved functional delivery of luminal proteins using engineered extracellular vesicles

The potential for engineered extracellular vesicles (EVs) to efficiently deliver biotherapeutics is still largely untapped. One of the key structures in determining cargo loading and subsequent functional delivery efficiency of engineered EVs is the sorting protein (scaffold). To determine the role of scaffold protein identity, a functional screen of scaffold proteins for efficient cargo delivery is required. Here, we applied the VEDIC (VSV-G plus EV-sorting Domain-Intein-Cargo) system, previously developed by our group, for the functional screen of 55 different scaffold proteins. Three tetraspanins (TSPAN2, TSPAN4 and TSPAN9) were identified that demonstrate enhanced intracellular delivery of cargo when compared to traditionally used CD63. We further explored the in vivo and ex vivo protein delivery performance of the best performing engineered EVs (TSPAN2) using melanoma xenografts and isolated primary cells from Cre-LoxP R26-LSL-tdTomato reporter mice, respectively. Finally, we report successful treatment of LPS-induced systemic inflammation by delivering a super-repressor inhibitor of NF-ĸB using TSPAN2 engineered EVs. This work highlights the importance of screening critical EV engineering elements, such as the scaffold protein, to modulate EV properties.

Extracellular vesicles as a promising platform of precision medicine in liver cancer

Extracellular vesicles (EVs) are natural carriers of biological information and play pivotal roles in intercellular communication. EVs are biocompatible, have low immunogenicity, and are capable of traversing biological barriers, making them ideal tools for disease diagnosis and therapy. Despite their promising prospects, the full realization of EVs potential faces several challenges. This article aims to comprehensively review the biological and molecular features of EVs, their applications in liver cancer and possible underlying mechanisms, and the critical challenges affecting the clinical translation of EVs-based therapies in liver cancer.

Proteomic profiling of serum small extracellular vesicles predicts post-COVID syndrome development

Post-COVID syndrome affects 10-35 % of COVID-19 patients, and up to 85 % of hospitalized individuals, underscoring the need for early identification of high-risk cases. We hypothesized that the proteomic profile of serum small extracellular vesicles (sEVs) obtained during acute SARS-CoV-2 infection could predict post-COVID syndrome. Serum samples from 59 patients, stratified as asymptomatic, moderate, or severe, were analyzed. sEVs were isolated, characterized by electron microscopy, nanoparticle tracking, and flow cytometry, then profiled via LC-MS. Classification models integrating comorbidities, acute symptoms, and sEV proteomics distinguished the three groups, with sEV data outperforming conventional measures. Of 620 identified proteins, 30 showed significant differences between symptomatic and asymptomatic patients, including 12 linked to complement activation. ELISA confirmed LC-MS results that serum sEVs of post-COVID patients had altered C1 inhibitor, C3, and C5 levels. These results suggest that sEV-based proteomics can enable earlier detection and more targeted follow-up for individuals at risk of post-COVID syndrome.

Small Extracellular Vesicles Orchestrate Cisplatin-Induced Ototoxicity: Potential Biomarker and Targets Discovery

Cisplatin-induced ototoxicity remains a clinical dilemma with limited mechanistic understanding and no food and drug administration (FDA)-approved therapies. Despite emerging roles of small extracellular vesicles (sEV) in drug ototoxicity, their molecular cargo profiles and causal roles to cisplatin-induced ototoxicity are unexplored. This study systematically investigates sEV derived from cochlear explants treated with cisplatin (Cis-sEV) and controls (Ctrl-sEV) using multi-omics profiling. Through small RNA sequencing, 83 differentially expressed microRNAs (miRNAs) are identified in Cis-sEV compared to Ctrl-sEV. Notably, mmu-miR-34a-5p, mmu-miR-140-5p, mmu-miR-15b-5p, mmu-miR-25-3p, and mmu-miR-339-5p are significantly upregulation in Cis-sEVs. Predicted target pathways of these differentially expressed miRNAs are enriched in apoptosis, inflammation, and cellular damage, indicating their potential involvement in cisplatin-induced cochlear damage. LC-MS/MS analysis reveals 90 upregulated and 150 downregulated proteins in Cis-sEV, with many involved in damage response. Specifically, CLTC, CCT2, ANXA6, and HSPA8 are uniquely upregulated proteins in Cis-sEV, and CLTC and ANXA6 are exclusively co-localized in hair cells (HCs) post-cisplatin exposure, suggesting that Cis-sEV originate primarily from damaged HCs. Moreover, CLTC in sEV may serve as a potential biomarker for cisplatin-induced ototoxicity as verified in both in vitro and in vivo models. This study provides novel insights into the molecular mechanisms of cisplatin-induced ototoxicity and identifies potential biomarker and therapeutic targets.

Theranostic potential of extracellular vesicles in reproductive tracts: implications for recurrent implantation failure

Embryo implantation is a critical step at the beginning of pregnancy, occurring during a specific and limited period known as the "implantation window". Successful implantation involves various signaling pathways and molecular interactions. Recent studies have highlighted the importance of extracellular vesicles (EVs) in mediating these complex interactions. Different cell types release EVs to transfer signals to other cells or tissues. Additionally, emerging evidence suggests that EVs regulate signaling between the developing embryo and endometrium. In this review, we summarize current findings that highlight the role of EVs in the reproductive tract, gamete production, and their potential roles in embryo development and implantation. We then examine studies emphasizing the role of EVs in embryo-maternal interactions and implantation. Finally, we will explore the theranostic potential of EVs in various aspects of assisted reproductive technology (ART), including modulation of embryo-maternal interactions, enhancement of embryo quality, and improvement of endometrial receptivity. A more comprehensive understanding of EVs in the pathology of recurrent implantation failure could support the development of personalized treatments.

Insights Into Heart-Tumor Interactions in Heart Failure

Heart failure (HF) often coexists with cancer. Beyond the known cardiotoxicity of some cancer treatments, HF itself has been associated with increased cancer incidence. The 2 conditions share common risk factors, mechanisms, and interactions that can worsen patient outcomes. The bidirectional relationship between HF and cancer presents a complex interplay of factors that are not fully understood. Recent preclinical evidence suggests that HF may promote tumor growth via the release of protumorigenic factors from the injured heart, revealing HF as a potentially protumorigenic condition. Our review discusses the biological crosstalk between HF and cancer, emphasizing the impact of HF on tumor growth, with inflammation, and modulating the immune system as central mechanisms. We further explore the clinical implications of this connection and propose future research directions. Understanding the mechanistic overlap and interactions between HF and cancer could lead to new biomarkers and therapies, addressing the growing prevalence of both conditions and enhancing approaches to diagnosis, prevention, and treatment.

Light-Controlled Small Extracellular Vesicle-Based Spherical Nucleic Acid Nanomotor for Enhanced Transdermal Delivery against Skin Aging

Small extracellular vesicles (sEV) derived from mesenchymal stem cells hold promise for anti-skin aging, yet their clinical application is hindered by poor transdermal permeability. Herein, we report an innovative light-controlled sEV-based spherical nucleic acid nanomotor (NM-ESNA). This nanosystem was composed of an sEV core and an MMP1-targeting siRNA shell, forming a 3D penetrative nanostructure. In addition, asymmetrically modified light-responsive gas-generating molecules were integrated into the nanomotor, enabling efficient dermal delivery. The light-controlled and enhanced transdermal delivery guaranteed synergistic anti-skin aging therapy through sEV-mediated paracrine effects and gene therapy targeting MMP1 in the dermis. On the basis of this deep transdermal delivery technology and the synergistic therapy strategy, NM-ESNA demonstrated outstanding anti-skin aging effects in a mouse model. This biocompatible nanosystem (NM-ESNA) enabled light-controlled and deep transdermal delivery, establishing a therapeutic platform with significant potential for sEV-based noninvasive anti-skin aging therapy.

LMTK3 regulation of EV biogenesis and cargo sorting promotes tumour growth by reducing monocyte infiltration and driving pro-tumourigenic macrophage polarisation in breast cancer

BACKGROUND

Lemur Tail Kinase 3 (LMTK3) promotes cell proliferation, invasiveness and therapy resistance, and its expression correlates with poor survival in several different malignancies, including breast cancer. Crosstalk through extracellular vesicles (EVs) is an increasingly appreciated mechanism of cell communication within the tumour immune microenvironment, which contributes to different aspects of cancer progression and plays a pivotal role in shaping tumour fate.

METHODS

Nanoparticle tracking analysis and transmission electron microscopy were used to study the effects of LMTK3 on EV size, while single particle interferometry allowed us to examine LMTK3-dependent effects on the subpopulation distribution of EVs. Quantitative mass spectrometry was used to profile LMTK3-dependent proteomics changes in breast cancer-derived EVs. Bioinformatics analysis of clinical data along with in vitro and cell-based assays were implemented to explore the effects of LMTK3-dependent EV protein cargo on the tumour immune microenvironment. To elucidate the mechanism through which LMTK3 impacts endosomal trafficking and regulates EV biogenesis, we used a variety of approaches, including in vitro kinase assays, confocal and electron microscopy, as well as in vivo subcutaneous and orthotopic breast cancer mouse models.

RESULTS

Here, we report that LMTK3 increases the average size of EVs, modulates immunoregulatory EV proteomic cargo and alters the subpopulation distribution of EVs released by breast cancer cells. Mechanistically, we provide evidence that LMTK3 phosphorylates Rab7, a key regulator of multivesicular body (MVB) trafficking, thereby reducing the fusion of MVBs with lysosomes and subsequent degradation of intralumenal vesicles, resulting in altered EV release. Moreover, LMTK3 causes increased packaging of phosphoserine aminotransferase 1 (PSAT1) in EVs, leading to a paracrine upregulation of phosphoglycerate dehydrogenase (PHGDH) in monocytes when these EVs are taken up. PSAT1 and PHGDH play key roles in the serine biosynthesis pathway, which is closely linked to cancer progression and regulation of monocyte behaviour. LMTK3 EV-induced elevated PHGDH expression in monocytes reduces their infiltration into breast cancer 3D spheroids and in vivo breast cancer mouse models. Furthermore, these infiltrating monocytes preferentially differentiate into pro-tumourigenic M2-like macrophages. Additional breast cancer mouse studies highlight the contribution of LMTK3-dependent EVs in the observed immunosuppressive macrophage phenotype. Finally, in vitro experiments show that pharmacological inhibition of LMTK3 reverses the pro-tumourigenic and immunomodulatory effects mediated by EVs derived from LMTK3 overexpressing cells.

CONCLUSION

Overall, this study advances our knowledge on the mechanisms of EV biogenesis and highlights a novel oncogenic role of LMTK3 in the breast TME, further supporting it as a target for cancer therapy.

Characterization of extracellular vesicle-associated DNA and proteins derived from organotropic metastatic breast cancer cells

BACKGROUND

While primary breast cancer (BC) is often effectively managed, metastasis remains the primary cause of BC-related fatalities. Gaps remain in our understanding of the mechanisms regulating cancer cell organotropism with predilection to specific organs. Unraveling mediators of site-specific metastasis could enhance early detection and enable more tailored interventions. Liquid biopsy represents an innovative approach in cancer involving the analysis of biological materials such as circulating tumor DNA and tumor-derived extracellular vesicles (EV) found in body fluids like blood or urine. This offers valuable insights for characterizing and monitoring tumor genomes to advance personalized medicine in metastatic cancers.

METHODS

We performed in-depth analyses of EV cargo associated with BC metastasis using eight murine cell line models with distinct metastatic potentials and organotropism to the lung, the bone, the liver, and the brain. We characterized the secretome of these cells to identify unique biomarkers specific to metastatic sites.

RESULTS

Small EVs isolated from all cell lines were quantified and validated for established EV markers. Tracking analysis and electron microscopy revealed EV secretion patterns that differed according to cell line. Cell-free (cf)DNA and EV-associated DNA (EV-DNA) were detected from all cell lines with varying concentrations. We detected a TP53 mutation in both EV-DNA and cfDNA. Mass spectrometry-based proteomics analyses identified 698 EV-associated proteins, which clustered according to metastatic site. This analysis highlighted both common EV signatures and proteins involved in cancer progression and organotropism unique to metastatic cell lines. Among these, 327 significantly differentially enriched proteins were quantified with high confidence levels across BC and metastatic BC cells. We found enrichment of specific integrin receptors in metastatic cancer EVs compared to EVs secreted from non-transformed epithelial cells and matched tumorigenic non-metastatic cells. Pathway analyses revealed that EVs derived from parental cancer cells display a cell adhesion signature and are enriched with proteins involved in cancer signaling pathways.

CONCLUSION

Taken together, the characterization of EV cargo in a unique model of BC organotropism demonstrated that EV-DNA and EV proteomes were informative of normal and cancer states. This work could help to identify BC biomarkers associated with site-specific metastasis and new therapeutic targets.

Exploring adipose tissue-derived extracellular vesicles in inter-organ crosstalk: Implications for metabolic regulation and adipose tissue function

Intercellular and inter-organ communication systems are vital for tissue homeostasis and disease development, utilizing soluble bioactive molecules for signaling. The field of extracellular vesicle (EV) biology has rapidly expanded in recent decades, highlighting EVs as effective bioactive nanovectors for cell-to-cell communication in various physiological and pathological contexts. Numerous studies indicate that adipocyte-derived EVs are crucial components of the adipose secretome, playing a key role in autocrine and paracrine interactions within adipose tissue, as well as in endocrine signaling. This review aims to present an updated perspective on EVs as mediators of communication between adipose tissue and other organs, while also examining their therapeutic potential in the light of recent advancements in EV biology research.

Mitochondrial Distribution and Osteocyte Mechanosensitivity

PURPOSE OF REVIEW

Mechanical loading of bone is an important physical stimulus for bone tissue remodeling and adaptation. It is transmitted from the extracellular matrix all the way to the osteocyte nucleus via the extracellular matrix-integrin-cytoskeleton-nucleus system. Mitochondria are integral in sensing of mechanical loads to allow the cell to adapt to its environment. This review provides a background of mitochondrial distribution in osteocytes especially during mechanical loading, discussing the importance of mitochondrial distribution in osteocyte mechanosensitivity and mechanotransduction.

RECENT FINDINGS

Mitochondria throughout the osteocyte are highly dynamic and provide essential metabolic and signal functions to regulate osteocyte morphology and function. They undergo the processes of fission and fusion accompanied by mitochondrial DNA distribution. The mitochondrial network structure and function in osteocytes can be regulated by mechanical loading. Interestingly, mitochondria can be transmitted by osteocytes into adjacent cells to communicate with them via tunneling nanotubes, migrasomes, and blebbisomes, causing changes in cell morphology and/or function. Mitochondrial distribution in or out osteocytes can be rearranged by physical and (bio)chemical signals via fission and fusion, as well as tunneling nanotubes, migrasomes, and blebbisomes. Mechanical loading-induced changes in mitochondria may drive signaling pathways of cell function in aging and diseases. More insights into interactions between neighbouring osteocytes and between osteocytes and other cell types would facilitate the development of new strategies to apply mitochondrial therapy for bone-related diseases.

Bioinspired Silk and Human Amniotic Membrane-Based MSC-sEV-Functionalized Wound Dressing Enhances Skin Regeneration: A Cell-Free Therapeutic Modality for Wound Care

Full-thickness wounds pose significant healing challenges due to their impaired regenerative capacity, persistent inflammation, and oxidative stress. Enhancing the bioactivity of silk fibroin (SF) and the mechanical strength of the human amniotic membrane (hAM) can improve wound healing outcomes. Mesenchymal stem cell (MSC)-derived small extracellular vesicles (sEVs) offer promising anti-inflammatory and antioxidant benefits, but their poor retention and painful application limits their clinical utility. To overcome these challenges, we developed a composite scaffold of SF and hAM (Sh), loaded with sEVs (ShE), designed to accelerate wound healing by modulating inflammation, oxidative stress, and tissue regeneration. ShE exhibited excellent physical stability, optimal swelling, degradation kinetics, hemocompatibility, and sustained sEV release. In vitro, it enhanced keratinocyte and fibroblast proliferation and migration, reduced oxidative stress, and provided immunomodulatory and pro-angiogenic effects. ShE significantly lowered ROS levels, suppressed PHA-activated PBMNC proliferation, facilitated macrophage polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, and promoted angiogenesis. In vivo, ShE accelerated wound closure within 21 days, outperforming DuoDERM, a commercial dressing. Histopathological analysis demonstrated improved epidermal maturation, dermal regeneration, and reduced scarring in ShE-treated wounds, confirming the superior tissue regeneration capacity. Additionally, its fabrication from medical waste and indigenous raw materials ensures cost-effectiveness and sustainability in healthcare applications. By synergistically regulating cell physiology for skin regeneration, ShE emerges as a promising, clinically viable, and affordable wound dressing for enhanced wound care management.

Isolation and characterization of extracellular vesicle subsets in donkey seminal plasma

Seminal plasma (SP), a fluid composed of secretions from the male genital tract, is rich in seminal extracellular vesicles (sEVs), nano-sized particles surrounded by a lipid bilayer membrane and loaded with functionally active molecules. Seminal EVs are secreted by functional cells of the male genital tract and play a key role in modulating reproductive processes, including sperm function and immune response in the female genital tract. The aim of this study was to isolate and characterize sEVs from donkey SP for the first time. Nine SP samples were collected from nine healthy and reproductive active donkeys. The SP samples were randomly pooled to create three pools (three SP samples per pool). The SP pools were subjected to differential centrifugation and size-exclusion chromatography to separately isolate two subsets of sEVs: small (S-) and large (L-). Orthogonal characterization of sEV samples was performed according to MISEV 2023 guidelines, including morphology (by cryogenic electron microscopy), concentration (by total protein concentration and total and CFSE positive particles by flow cytometry [FC]), particle size distribution (by dynamic light scattering), purity (by albumin assessment by FC), and specific EV protein markers (tetraspanins CD9, CD63, and CD81, and HSP70 by FC). The results showed that donkey SP is highly enriched in sEVs. Size differences were found between both sEV subsets, with S-sEVs being smaller (∼160 nm) and L-sEVs larger (∼290 nm). Both sEV subsets were positive for the four EV protein markers. However, the percentage of CD81-positive events was higher in S-sEV samples than in L-sEV samples (P < 0.05). This study is the first to isolate and characterize sEVs in donkey SP, demonstrating their heterogeneity and suggesting differences in biogenesis and function between S-sEVs and L-sEVs.

Comparison of the Immunomodulatory Roles of Porcine Milk-Derived Extracellular Vesicles from Different Stages of Lactation

Milk-derived extracellular vesicles (MEV) have received increasing attention due to their physiological benefits for newborn growth and development. However, their physiological characteristics and immunomodulatory capacities during lactation remain unclear. In this study, we isolated MEV from porcine milk at day 1, week 1, week 2, and week 3 after parturition and compared their differences by common EV characterization, showing the higher concentration and smaller mean size of MEV from colostrum. Porcine MEV could be internalized by RAW264.7 macrophages and functionally deliver immune-related microRNAs (miRNAs). Furthermore, MEV promoted macrophage polarization toward the M2-like phenotype and exerted anti-inflammatory effects in vitro. Mice models with sepsis also displayed that MEV suppressed the secretion of pro-inflammatory cytokines in serum and drove an anti-inflammatory M2-like phenotype of the spleen, ultimately weakening immune responses. Especially, MEV from colostrum exhibited the most robust effects on immunoregulation. Overall, this study provides valuable information for MEV secretion patterns and their differences in immunomodulatory bioactivities.

Extracellular Vesicles as Emerging Therapeutic Strategies in Spinal Cord Injury: Ready to Go

Spinal cord injury (SCI) is a prevalent central nervous system disorder that causes significant disability and mortality. Unfortunately, due to the complex pathophysiological mechanisms involved, there remains a critical paucity of effective therapeutic interventions capable of achieving neural tissue regeneration and functional recovery enhancement in SCI patients. The advancements in extracellular vesicles (EVs) as a cell-free therapy for SCI have displayed notable benefits. These include their small size, low immunogenicity, capacity to target specific areas, and ability to cross the blood‒brain barrier (BBB). EVs offer the potential to not only repair tissue damage and stimulate regeneration but also effectively deliver and release them at the site of SCI when combined with diverse biomaterials. This review explores the biological role and importance of EVs in treating SCI, highlighting the combined use of modified EVs with different biomaterials and their potential for future applications. It presents new and hopeful treatment approaches for individuals afflicted with SCI.

Mineralized Osteoblast-Derived Exosomes and 3D-printed Ceramic-based Scaffolds for Enhanced Bone Healing: A Preclinical Exploration

In regenerative medicine, addressing the complex challenge of bone tissue regeneration demands innovative strategies. Exosomes, nanoscale vesicles rich in bioactive molecules, have shown great promise in tissue repair. This study focuses on exosomes derived from mineralized osteoblasts (MOBs), which play a pivotal role in bone formation. We investigated the therapeutic potential of exosomes isolated from osteoblasts cultured in osteogenic medium for 21 days, delivered via 3D-printed gyroid scaffolds composed of hydroxyapatite (HA) and tricalcium phosphate (TCP). The exosomes were characterized through nanoparticle tracking analysis to determine size, morphology, and concentration, while proteomics revealed their cargo contents. In vitro, rabbit bone marrow mesenchymal stromal cells (rBMSCs) were cultured as monolayers and within ceramic scaffolds, where MOB-derived exosomes were shown to promote osteogenic differentiation. In vivo, their osteoconductive and bone augmentation capabilities were evaluated in two rabbit calvarial models, while the osteoinductive potential was further tested in a heterotopic mouse model. Neo-bone formation was assessed using µCT and histological analysis. Our findings demonstrated that MOB-derived exosomes upregulated bone-related gene expression and promoted mineralization in rBMSCs, even in the absence of osteogenic medium. Proteomics confirmed the presence of bone-associated proteins in these exosomes. In rabbit models, however, exosomes did not significantly enhance bone formation. In contrast, in the heterotopic mouse model, exosomes functionalized onto ceramic scaffolds exhibited strong osteoinductive activity. This study highlights the potential of MOB-derived exosomes to enhance 3D-printed ceramic scaffolds for bone regeneration, offering a promising avenue for bone healing without the need for additional growth factors or stem cells. STATEMENT OF SIGNIFICANCE: The here presented report of our project not only advances our understanding of the role of exosome-functionalized scaffolds in bone regeneration but also proposes a promising alternative to traditional growth factor- or cell-based approaches. We are confident that this study represents a novel and impactful contribution to the field.

Utilizing Extracellular Vesicles from Phaeodactylum tricornutum as a Novel Approach for Protecting the Skin from Oxidative Damage

Oxidative stress is a principal factor contributing to skin damage induced by deleterious stimuli, including ultraviolet (UV) radiation. Microalgae-derived extracellular vesicles (EVs), particularly those from Phaeodactylum tricornutum (PTEV), are gaining recognition as a potential therapeutic avenue for restoring skin homeostasis, owing to their scalable production and multifaceted biological activities. This study evaluates the therapeutic effects of PTEV on oxidative damage in H2O2-stimulated HaCaT cells and UV-exposed KM mouse models, based on the extraction and characterization of PTEV. Subsequently, the oxidative stress injury model of HaCaT cells induced by H2O2 and the acute photodamage model of KM mice skin induced by UV were established. The results show that HaCaT cells exhibit a time-dependent uptake of PTEV, confirming that PTEV is nontoxic and has the potential for intercellular cross-boundary regulation. Treatment with PTEV can enhance the vitality of H2O2-stimulated HaCaT cells, reduce intracellular ROS levels, and increase antioxidant enzyme activity in the cells. Further evaluation revealed that PTEV can inhibit UV-induced thickening of the epidermis and degradation of collagen fibers in mice by suppressing the overexpression of matrix metalloproteinase (MMP-3) induced by UV. It enhances the expression of type I collagen (COL1A1) and increases the activity of antioxidant enzymes, as well as the overall antioxidant capacity of tissues. Additionally, PTEV reduces the increase in malondialdehyde levels and lowers the expression levels of inflammatory factors TNF-α and IL-6, thereby protecting the skin barrier and function in mice with acute photodamage. Continuous production of PTEV offers promising applications in therapeutic strategies.

Multi-line lateral flow immunoassay for the detection and subtyping of breast cancer-derived small extracellular vesicles

Cancer cell-derived small extracellular vesicles (sEVs) are new promising biomarkers for improved cancer diagnosis. A multi-line lateral flow immunoassay (LFIA) has been proposed for sensitive detection and subtyping of breast cancer-derived sEVs. The expression of cancer surface biomarkers (EpCAM) was confirmed through colorimetric analysis of cell line-derived sEVs (p = 0.076) and patient samples, highlighting the potential for their use as a clinical aid.

Integrated Single Nanoparticle Analysis for Rapid Quantification of Spatiotemporal Crosstalk between Herpes Simplex Virus-1 and Extracellular Vesicles

Cells secrete extracellular vesicles (EVs) to mediate precise communication during viral infections, yet the spatiotemporal regulation of EV composition by herpes simplex virus 1 (HSV-1) remains poorly understood. Here, we develop an integrated single-nanoparticle analysis platform combining nanoporous membrane-based EV isolation with an on-chip immunoassay to quantitatively probe EV-HSV-1 interplay throughout infection. A dual-membrane filter design significantly enhances nanoparticle recovery, enabling high-sensitivity single-particle detection. We reveal that HSV-1-infected neural stem cells display viral glycoprotein B on EV surfaces at an early stage (<8 hpi), while intact virions are selectively packaged into EVs later (24-48 hpi). Proteomic profiling indicates infected cell-derived EVs facilitate antigen processing and presentation, potentially amplifying antiviral responses. Functional studies further demonstrate EVs promote viral entry at late stages (48 hpi), likely via EV-virion encapsulation. These findings elucidate a dynamic EV-virus interplay, offering insights into HSV-1 pathogenesis and EV-mediated immune modulation. Our platform provides a transformative approach for advancing infection diagnostics and therapeutics.

FACS-Proteomics strategy toward extracellular vesicles single-phenotype characterization in biological fluids: exploring the role of leukocyte-derived EVs in multiple sclerosis

BACKGROUND

The isolation and proteomics characterization of extracellular vesicles (EVs) from body fluids is challenging due to their vast heterogeneity. We have recently demonstrated that Fluorescence-activated Cell Sorting (FACS) efficiently isolates the whole EV circulating compartment directly from untouched body fluids enabling a comprehensive EV proteomics analysis.

RESULTS

Here, we characterized, for the first time, a single-phenotype EV subset by sorting leukocyte-derived EVs (Leuko EVs) from peripheral blood and tears of healthy volunteers. Using an optimized and patented staining protocol of the whole EV compartment we identified and excluded non-EV particles, debris and damaged EVs. We further isolated, using an anti-CD45 antibody, Leuko EVs (CD45+ EVs), reaching a high level of purity (> 90%). Purified Leuko EVs were characterized using atomic force microscopy, nanoparticle tracking, and shotgun proteomics analysis revealing a similar coded protein cargo in both biological fluids. Subsequently, the same workflow was applied to tears from Relapsing-Remitting Multiple Sclerosis (RRMS) patients, revealing a Leuko EVs protein cargo enrichment that reflects the neuroinflammatory condition characteristics of RRMS. This enrichment was evidenced by the activation of upstream regulators TGFB1 and NFE2L2, which are associated with inflammatory responses. Additionally, the analysis identified markers indicative of endothelial cell proliferation and the development of enhanced vascular networks, with AGNPT2 and VEGF emerging as activated upstream regulators. These findings indicate the complex interplay between inflammation and angiogenesis in RRMS.

CONCLUSIONS

In conclusion, our combined FACS-Proteomics strategy offers a promising approach for biomarker discovery, analysing cell-specific EV phenotypes directly from untouched body fluids, advancing the clinical value of tears EVs and improving the understanding of EV-mediated processes in vivo. Data are available via ProteomeXchange with the identifier PXD049036 and in EV-TRACK knowledgebase with ID: EV240150.

Rapid Identification of Esophageal Squamous Cell Carcinoma Biomarkers by MALDI-TOF MS Fingerprinting of Extracellular Vesicles

Esophageal cancer is a major global health challenge, with high incidence and mortality due to the lack of rapid and sensitive diagnostic tools and specific biomarkers. Cancer-cell-derived extracellular vesicles (EVs) carry unique proteins and nucleic acids, making them valuable sources of cancer biomarkers. We report an integrated method that combines an ultrafast exosome isolation system (EXODUS) with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) to detect EVs and identify protein biomarkers for diagnosing and monitoring esophageal squamous cell carcinoma (ESCC). EVs derived from 20 mL culture medium supernatant of ESCC cells with varying degrees of differentiation serve as analysis models. We use EXODUS to isolate EVs rapidly. We then analyze the intact EVs using MALDI-TOF MS, which provides cell line-specific EV fingerprints in minutes. These protein fingerprints allow the discrimination of ESCC from normal control cells and enable the classification of ESCC based on the degree of cell differentiation. We explore critical EV biomarker peaks for ESCC diagnosis (5555 m/z, 8603 m/z, etc.) and monitoring (2268 m/z, etc.). Potential EV biomarker candidates, including YBX1, DIRAS2, HIST1H2AH, and MYBBP1A, are identified through tandem mass tag (TMT) proteomics. We tentatively assign the protein identities of EV marker peaks by correlation with the TMT proteomics. Applying this method to plasma-derived EVs shows promise for rapid, minimally invasive diagnosis and monitoring of ESCC.

Tumour-derived microparticles obtained through microwave irradiation induce immunogenic cell death in lung adenocarcinoma

Tumour-derived microparticles (TMPs), extracellular vesicles traditionally obtained upon ultraviolet (UV) radiation of tumour cells, hold promise in tumour immunotherapies and vaccines and have demonstrated potential as drug delivery systems for tumour treatment. However, concerns remain regarding the limited efficacy and safety of UV-derived TMPs. Here we introduce a microwave (MW)-assisted method for preparing TMPs, termed MW-TMPs. Brief exposure of tumour cells to short-wavelength MW radiation promotes the release of TMPs showing superior in vivo antitumour activity and safety compared with UV-TMPs. MW-TMPs induce immunogenic cell death and reprogramme suppressive tumour immune microenvironments in different lung tumour models, enabling dual targeting of tumour cells by natural killer and T cells. We show that they can efficiently deliver methotrexate to tumours, synergistically boosting the efficacy of PD-L1 blockade. This MW-TMP development strategy is simpler, more efficient and safer than traditional UV-TMP methods.

Neutrophil-Derived Extracellular Vesicles for Facile Delivery of Diagnostic Agents to Tumor Microenvironments

Targeted delivery of diagnostic and therapeutic agents to tumor microenvironments using nanoparticles improves the efficacy of these agents and reduces their unwarranted side effects. Numerous synthetic nanoparticle systems have been designed for this very purpose, but few have translated clinically due to poor efficacy-to-cost and efficacy-to-toxicity ratios. Biological nanoparticles such as modified extracellular vesicles (EVs) that are likely to have lower toxicities have also been developed but face challenges in clinical translation as they have primarily been produced from cancerous cells/cell lines and have high batch-to-batch variability. To overcome these issues, herein, we demonstrate that EVs isolated from neutrophils may be loaded with a specific diagnostic agent (indocyanine green) in a facile manner within a few hours, that these agent-loaded EVs are retained in vivo in mouse tumors for longer with a ∼5-fold increase in retention when compared to free diagnostic agents and hence facilitate short-term longitudinal imaging of the tumor microenvironments. The use of an individual's own cell-derived EVs requiring minimal ex vivo manipulations increases the likelihood of translating such a system into the clinic.

Mesenchymal stem cells protect the integrity of the alveolar epithelial barrier through extracellular vesicles by inhibiting MAPK-mediated necroptosis

BACKGROUND

Alveolar‒capillary barrier disruption is a hallmark of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). The contribution of necroptosis to the compromised alveolar-barrier in ALI remains unclear. Mesenchymal stem cells (MSCs) may contribute to tissue repair in ALI and ARDS. Here we evaluated the efficacy and explored the molecular mechanisms of menstrual blood-derived endometrial stem cells (MenSCs) and MenSC-derived extracellular vesicles (MenSC-EVs) in ALI-induced alveolar epithelial barrier dysfunction.

METHODS

Human lung epithelial cells were stimulated with endotoxin and treated with MenSCs or MenSC-EVs, and their barrier properties were evaluated. Lipopolysaccharide (LPS)-injured mice were treated with MenSCs or MSC-EVs, and the degree of lung injury and the alveolar epithelial barrier of the lung tissue were assessed.

RESULTS

We found that MenSCs reduced lung injury and restored alveolar-barrier integrity in lung tissue. In vitro, MenSCs reduced paracellular permeability and restored barrier integrity in human lung epithelial cells. MenSC-EVs replicated all these MenSC-mediated changes. Mechanistic research revealed that MenSCs inhibited MAPK signaling and necroptosis. JNK inhibition SP600125, and ERK inhibition U0126 or inhibition of necroptosis with Nec-1 or GSK872 diminished the beneficial anti-epithelial barrier dysfunction effects of MenSCs or MenSC-EVs.

CONCLUSIONS

Our results suggest that human menstrual blood-derived endometrial stem cells mitigate lung injury and improve alveolar barrier properties by inhibiting MAPK-mediated necroptosis through extracellular vesicles, supporting the application of MenSCs or MenSC-derived extracellular vesicles to treat ALI or ARDS.

Coupling of Intracellular Calcium Homeostasis and Formation and Secretion of Matrix Vesicles: Their Role in the Mechanism of Biomineralization

The human bone is a dynamic, highly vascularized tissue composed of 60-70% minerals, which include mainly calcium phosphate (CaP) in the form of hydroxyapatite (HA) crystals, 30% organic matrix composed of type I collagen fibers, and less than 5% water and lipids. The crystals are formed inside the matrix vesicles (MVs) and are then released in the organic collagen-based fibrous matrix. Extracellular matrix (ECM) formation and mineralization processes, named osteogenesis, are associated with human mesenchymal stem cells (hMSCs) undergoing differentiation into osteoblasts (osteoblastogenesis). Osteogenesis is regulated by multiple intracellular signaling and genetic pathways and by environmental factors. Calcium flow is finely regulated and plays a key role in both osteoblastogenesis and osteogenesis. The formation and accumulation of CaP, the biogenesis of MVs, their secretion, and the deposition of HA crystals to fill the organic bone matrix are the fundamental events in the biomineralization process. In this paper, I will describe and discuss the recent findings and hypothesis on the molecular mechanism regulating this process.

Extracellular Vesicles in Acute Kidney Injury: Mechanisms, Biomarkers, and Therapeutic Potential

Acute kidney injury (AKI) has a high morbidity and mortality rate but can only be treated with supportive therapy in most cases. The diagnosis of AKI is mainly based on serum creatinine level and urine volume, which cannot detect kidney injury sensitive and timely. Therefore, new diagnostic and therapeutic molecules of AKI are being actively explored. Extracellular vesicles (EVs), secreted by almost all cells, can originate from different parts of the kidney and mediate intercellular communication between various cell types of nephrons. At present, numerous successful EV-based biomarker discoveries and treatments for AKI have been made, such as the confirmed diagnostic role of urine-derived EVs in AKI and the established therapeutic role of mesenchymal stem cell-derived EVs in AKI have been confirmed; however, these related studies lack a full discussion. In this review, we summarize the latest progression in the profound understanding of the functional role of EVs in AKI caused by various etiologies in recent years and provide new insights into EVs as viable biomarkers and therapeutic molecules for AKI patients. Furthermore, the current challenges and prospects of this research area are briefly discussed, presenting a comprehensive overview of the growing foregrounds of EVs in AKI.

Diagnostic and prognostic roles of endothelial- and platelet-derived extracellular vesicles in cardiovascular diseases

Extracellular vesicles (EVs) are membrane-bound structures released by all cell types. They play a critical role in intercellular communication by transferring their cargo, comprising proteins, lipids, metabolites, RNAs, miRNAs, and DNA fragments, to recipient cells. This transfer influences gene expression, signaling pathways, and cellular behavior. Due to their ability to alter the physiology of recipient cells, EVs hold significant therapeutic potential. Additionally, EVs are implicated in various physiological and pathological processes, including immune regulation, cancer progression, and cardiovascular diseases. EVs have been detected in many biological fluids, such as peripheral blood, saliva, urine, cerebrospinal fluid, and breast milk. The cargo of EVs dynamically reflects the physiological and pathological state of their parent cells, making them promising candidates for liquid biopsies in various clinical conditions. Specifically, different EV subtypes in cardiovascular diseases have been studied, with both endothelial and platelet-derived EVs playing significant roles in cardiovascular pathologies. This review focuses on the diagnostic and prognostic potential of endothelial and platelet-derived EVs in cardiovascular diseases, highlighting the role of EV subpopulations.

Dynamic characteristics of metabolism and small extracellular vesicles during malignant transformation of BEAS-2B cells induced by coal tar pitch extract

Lung cancer poses a significant global burden with rising morbidity and mortality. Coal tar pitch-induced lung cancer is an occupational disease where early detection is crucial but challenging due to unclear pathogenesis. We established a malignant transformation model using BEAS-2B cells treated with coal tar pitch extract (CTPE). Macro- and micro-observations showed CTPE-induced alterations, including changes in cell morphology, enhanced proliferation and migration abilities, upregulated EGFR expression, modified levels of CYP1A1 and GSTM1 metabolizing enzymes, and a transition towards a mesenchymal phenotype. These findings strongly suggest that the cells have undergone malignant transformation. Metabolomics analysis revealed changes in 1120 metabolites, with 31 co-expressed, mainly in energy and amino acid metabolism. Small extracellular vesicles (SEVs) concentrations and EGFR levels were significantly altered. Correlation analysis identified a relationship between these biomarkers, implying their potential significance as early events in the initiation and progression of lung cancer. These findings provide valuable insights and a rationale for lung cancer screening and mechanistic investigations, thereby contributing to a deeper understanding of the disease.

ExoCarta 2024: A Web-based Repository of Small Extracellular Vesicles Cargo

Small extracellular vesicles (sEVs) are small membrane vesicles of endocytic origin secreted into the extracellular environment by all cell types and are known to play a crucial role in intercellular and intracellular communication. These vesicles contain proteins, nucleic acids and lipids and their molecular content reflect the normal and pathophysiological conditions of the host cells. Hence, there is a significant interest in cataloguing the molecular content of sEVs in various conditions as this would aid researchers in understanding the biological roles and altered cellular processes under various diseases and healthy state. Here we report ExoCarta (https://www.exocarta.org), a freely accessible web-based compendium of studies that encompasses DNA, RNA, proteins, and lipids that are detected in sEVs. ExoCarta catalogues both published and unpublished sEV studies. Current version of ExoCarta contains data from 1249 sEV studies, 119,489 protein entries, 15,868 RNA entries, 3,946 lipid entries and quantitative data for 24,073 entries. QUANT, a quantitative plugin, enables users to compare protein abundance between conditions in a study for gene/protein of interest in real time. ExoCarta provides Gene Ontology (GO) annotations and reactome pathways along with dynamic protein-protein interaction networks, for sEV proteins. A tab delimited file containing the most identified sEV proteins is available for users to download. The integration of sEV DNA studies, QUANT and regularly updated dataset of the ExoCarta database makes it an invaluable resource for small extracellular vesicles researchers across the globe.

Machine learning-assisted washing-free detection of extracellular vesicles by target recycling amplification based fluorescent aptasensor for accurate diagnosis of gastric cancer

Extracellular vesicles (EVs) are promising non-invasive biomarkers for cancer diagnosis. EVs proteins play a critical role in tumor progress and metastasis. However, accurately and reliably diagnosing cancers is greatly limited by single protein marker on EVs. Here, we reported an accurate diagnosis model of gastric cancer by analyzing five types of EVs surface proteins using machine learning in a retrospective study design. A washing-free detection method based on aptasensor and exonuclease Ⅰ was used to profile EVs surface proteins. The aptamer was designed as hairpin structure. The presence of target protein positive EVs converted the conformation of hairpin probes, which subsequently degraded by exonuclease Ⅰ. The exposed target protein could bind with and then open new hairpin probes, thus forming an amplification cycle. The lengths of different detection probes were optimized for detection. With the combination of five target proteins, five machine learning algorithms were compared to achieve a higher diagnostic accuracy. The best model, XGBoost, validated with 20 % of detection results could reach an accuracy of 0.8421. Furthermore, the XGBoost-based surface protein analysis could precisely identify gastric cancer patients with the area under the curve value of 0.9347 (95 % confidential interval (CI) = 0.8590 to 1.000). Since our method utilized a simple and versatile design of detection probes, its diagnostic scope could potentially be expanded to include different protein markers and accurately diagnose other diseases in the future.

Characterization of small extracellular vesicles from ovarian cancer patients and pre-diagnostic patient samples: Evidence from the Danish blood donor study

AIM

Ovarian cancer (OC) is the leading cause of gynecological cancer deaths. Current biomarkers of OC are not specific or sensitive enough. Extracellular vesicles (EVs), EV surface proteins and their cargo microRNA (miRNA) show potential as biomarkers. This study aimed to characterize the ability of EVs to identify early OC-biomarkers among blood donors six months before their diagnosis.

METHODS

Study groups of OC patients, benign tumor patients (B), healthy blood donors (Control), and blood donors with incident OC diagnosis within six months of the last blood draw (Pre-diagnostic; PD) were established. Small EVs were enriched from plasma using ultracentrifugation. EVs were characterized by Dynamic Light Scattering (DLS), EV Array, NanoFlow Cytometry, Nanoparticle Tracking Analysis, and Western blots. RNA from EVs was isolated. A discovery study was performed on OC and B patients using the TaqMan Array Human MicroRNA A card. A validation study of 9 specific miRNAs was performed using RT-qPCR.

RESULTS

With DLS, it was identified that the OC patients' EVs were more heterogeneous in size compared to the other groups. Western blot identified CD63 and TSG101 in the EV enrichments. EV Array assessed 22 known protein biomarkers. TaqMan MicroRNA Array cards indicated a differential miRNA abundance between OC and B; however, technical replication and validation could not validate this pattern.

CONCLUSION

This study has analyzed EVs in OC, B, Control, and PD women. More extensive investigations of EV CD9, CD151, and CD81 in conjunction with other risk factors and well-known biomarkers like CA125 or HE4 should be the main objectives of future research.

Extracellular vesicle-associated miR-515-5p from adipose tissue regulates placental metabolism and fetal growth in gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) affects 2-20% of pregnant women worldwide and is linked to fetal overgrowth, increased perinatal morbidity, and mortality, as well as a higher risk of developing cardiovascular disease later in life for mother and child. MicroRNAs (miRNAs), which regulate gene expression, can be transported within extracellular vesicles (EVs). Adipose tissue-derived EVs have been associated with changes in placental metabolism in GDM, potentially influencing cardiovascular health outcomes. This study aimed to evaluate the miRNA profile in EVs from omental adipose tissue in GDM and their effect on placental nutrient uptake and fetal growth.

METHODS

This case-control study included patients with normal glucose tolerance (NGT) and GDM. We conducted a miRNA expression profiling on omental adipose tissue and its derived EVs from women with NGT (n = 20) and GDM (n = 36). Trophoblast cells were utilized to assess the effect of EVs on glucose and fatty acid uptake, pro-inflammatory cytokine, and chemokine release. Double-stranded miRNA mimics were used to investigate the effect of selected miRNAs on trophoblast cells. Subsequently, the impact of EVs from NGT and GDM, as well as miR-515-5p, on in vivo glucose tolerance and fetal growth was assessed in pregnant mice.

RESULTS

Fifty-four miRNAs showed significant differences between EVs from the adipose tissue of NGT and GDM groups. EVs from GDM increased glucose uptake in trophoblast cells, whereas EVs from NGT increased the secretion of CXCL8, IL-6, CXCL1, CXCL4, and CXCL5 from trophoblasts compared to the effect without EVs. Specifically, miR-515-5p increased glucose uptake and abolished TNF-α-dependent increase in pro-inflammatory cytokines and chemokines from trophoblast cells. Injection of pregnant mice with EVs from NGT adipose tissue loaded with miR-515-5p resulted in increased fetal weight and glucose levels.

CONCLUSION

miR-515-5p, specifically encapsulated within EVs from omental adipose tissue in GDM, regulates placental nutrient uptake, glucose homeostasis, and fetal growth.

Proteomic study of plasma and L1CAM-captured exosomal proteins in children with autism spectrum disorders

Autism spectrum disorder (ASD) has become a neurodevelopmental disorder that seriously endangers the health of infants and children. In order to explore the pathogenesis of the disease and search for early diagnostic biomarkers. In this study, plasma exosomes (PEs) and neural cell adhesion molecule L1 (L1CAM)-captured exosomes (LCEs) of ASD and controls were extracted and lysed to obtain proteins. Isobaric tags for relative and absolute quantitation (iTRAQ) proteomics were applied to investigate the differences in the expression of PEs and LCEs proteins between the two groups. Twenty-eight plasma exosomal differentially expressed proteins (DEPs) were identified, which were mainly associated with immunity, inflammation, complement and coagulation, and lipoprotein metabolism and transport. Twenty L1CAM-captured exosomal DEPs were identified, which were mainly involved in cytoskeleton, tight junctions, focal adhesion, and platelet-associated pathways. Meanwhile, our results suggested that processes or signaling pathways associated with the DEPs from plasma exosomes may be activated, whereas those associated with L1CAM-captured exosome may be inhibited. These processes or signaling pathways have been reported to be associated with ASD in previous studies. These DEPs have the potential to be diagnostic markers. This study provides new insights into disease mechanisms and diagnostic markers of ASD.

Therapeutic and diagnostic potential of extracellular vesicle (EV)-mediated intercellular transfer of mitochondria and mitochondrial components

Extracellular vesicles (EVs) facilitate the transfer of biological materials between cells throughout the body. Mitochondria, membrane-bound organelles present in the cytoplasm of nearly all eukaryotic cells, are vital for energy production and cellular homeostasis. Recent studies highlight the critical role of the transport of diverse mitochondrial content, such as mitochondrial DNA (mt-DNA), mitochondrial RNA (mt-RNA), mitochondrial proteins (mt-Prots), and intact mitochondria by small EVs (<200 nm) and large EVs (>200 nm) to recipient cells, where these cargos contribute to cellular and mitochondrial homeostasis. The interplay between EVs and mitochondrial components has significant implications for health, metabolic regulation, and potential as biomarkers. Despite advancements, the mechanisms governing EV-mitochondria crosstalk and the regulatory effect of mitochondrial EVs remain poorly understood. This review explores the roles of EVs and their mitochondrial cargos in health and disease, examines potential mechanisms underlying their interactions, and emphasizes the therapeutic potential of EVs for neurological and systemic conditions associated with mitochondrial dysfunction.

Therapeutic Potential and Translational Challenges for Bacterial Extracellular Vesicles in Inflammatory Bowel Disease

Despite the availability of numerous new immune-directed therapeutics, the major constituents of inflammatory bowel disease (IBD)-ulcerative colitis (UC) and Crohn's disease (CD)-continue to afflict millions worldwide, resulting in significant morbidity and long-term health risks. IBD results from a triad of immune, environmental (eg, gut microbiome), and genetic (including epigenetic) mechanisms, and therefore has been subject to a wide variety of therapeutic strategies. Among these, the administration of probiotics, particularly Gram-positive lactic acid bacteria (LAB), targeting both immune and environmental factors, has shown promising potential for efficacy in selected populations in early clinical trials. However, knowledge gaps and inconsistent efficacy currently prevent recommendations for the use of probiotics in larger IBD patient populations. The inconsistent efficacy of probiotics is likely due to variable cell viability and potency after administration, further exacerbated by IBD patient heterogeneity. Thus, an alternative to live probiotics for IBD has emerged in the form of bacterial extracellular vesicles (BEVs)-cell-secreted nanovesicles containing abundant bioactive cargo that, like live probiotics, can regulate immune and environmental factors but with fewer viability limitations and safety concerns. In this review, we summarize the work done to date establishing the potential of BEVs to provide the therapeutic benefits in IBD and discuss the hurdles BEVs must overcome to achieve clinical translation. We also consider future directions for BEV therapeutics, especially treatment potential for necrotizing enterocolitis (NEC), which shares similarities in pathophysiology with IBD.

Characterization of Extracellular Vesicles from Infrapatellar Fat Pad Mesenchymal Stem/Stromal Cells Expanded Using Regulatory-Compliant Media and Inflammatory/Hormonal Priming

Osteoarthritis (OA) remains a leading cause of disability worldwide, with no disease-modifying therapies currently available for treatment. The infrapatellar fat pad (IFP) harbors mesenchymal stem/stromal cells (MSC) with potent immunomodulatory and regenerative properties, making them a promising candidate for OA treatment. A growing body of evidence suggests that the therapeutic effects of MSC are largely mediated by their extracellular vesicles (EVs), which carry bioactive cargo that modulates inflammation and tissue repair. However, optimizing MSC-derived EVs as a cell-free therapeutic approach requires an in-depth understanding of how culture conditions and inflammatory/hormonal priming influence their functional properties. In this study, IFP-MSC were expanded in regulatory-compliant human platelet lysate (HPL) and xeno-/serum-free (XFSF) media and primed with an inflammatory/fibrotic cocktail (TIC) with oxytocin (OXT) to assess the impact on their immunophenotypic profile and EV cargo. The immunophenotype confirmed that TIC+OXT-primed MSC retained key immunomodulatory surface markers, while EV characterization verified the successful isolation of CD63+/CD9+ vesicles. Pathway enrichment analysis of both HPL- and XFSF- TIC+OXT EVs cargo identified key miRNAs associated with immune regulation, tissue repair, and anabolic signaling. Functional assays revealed that TIC+OXT EVs promoted M2-like anti-inflammatory macrophage polarization and exhibited chondroprotective properties in chondrocytes/synoviocytes inflammatory osteoarthritic assay. These findings highlight the therapeutic potential of TIC+OXT-primed IFP-MSC-derived EVs as immunomodulatory and chondroprotective agents, offering a promising strategy for OA treatment through a clinically viable, cell-free approach.

Sensitive detection of small extracellular vesicles using a gold nanostar-based SERS assay

Small extracellular vesicles (sEVs) are lipid bilayer-bound vesicles that carry critical biomarkers for disease detection. However, the inherent heterogeneity and complexity of sEV molecular characteristics pose significant challenges for accurate and comprehensive molecular profiling. Traditional analytical methods, including immunoblotting, enzyme-linked immunosorbent assay (ELISA), and flow cytometry, exhibit several limitations, such as being time-consuming, requiring large sample volumes, and demonstrating relatively low sensitivity. Therefore, there is an urgent need to develop a highly sensitive and specific assay for the reliable detection of sEVs. Surface-enhanced Raman scattering (SERS) assays have emerged as a promising approach for sEV detection, offering advantages including high sensitivity and specificity. In the proposed SERS assay, SERS nanotags - comprising nanoparticles coated with Raman-active molecules and conjugated with antibodies - are employed to label surface-bound molecules on sEVs. This approach facilitates the generation of a high-intensity signal from molecules present in low abundance. Recently, anisotropic nanoparticles, such as star-shaped nanostructures, have garnered interest due to their ability to significantly amplify generated SERS signals for ultra-sensitive biomarker detection. In this study, we explore the application of gold nanostars (AuNSs) as SERS nanotags for the detection of sEVs. In principle, AuNS-based SERS nanotags were used to label the EpCAM protein, which can be found on the surface of cancer cell derived sEVs, and then sEV labelled SERS nanotags were captured by CD9-conjugated magnetic beads to form an immunocomplex, which exhibits a SERS signal. Our results demonstrate that the proposed SERS assay utilizing AuNSs provides high specificity and sensitivity, with a detection limit as low as 2.47 × 103 particles per μL. Furthermore, the assay was tested with spiked plasma samples (cancer cell-derived sEVs spiked into healthy plasma), showing that its specificity remains unaffected by the presence of plasma. These findings suggest that the SERS assay incorporating AuNSs holds significant promise as an effective and reliable detection method for potential clinical applications.

Platelet Extracellular Vesicles as Natural Delivery Vehicles for Mitochondrial Dysfunction Therapy?

Mitochondria are vital for energy production, metabolic regulation, and cellular signaling. Their dysfunction is strongly implicated in neurological, cardiovascular, and muscular degenerative diseases, where energy deficits and oxidative stress accelerate disease progression. Platelet extracellular vesicles (PEVs), once called "platelet dust", have emerged as promising agents for mitigating mitochondrial dysfunction. Like other extracellular vesicles (EVs), PEVs carry diverse molecular cargo and surface markers implicated in disease processes and therapeutic efficacy. Notably, they may possibly contain intact or partially functional mitochondrial components, making them tentatively attractive for targeting mitochondrial damage. Although direct research on PEVs-mediated mitochondrial rescue remains limited, current evidence suggests that PEVs can modulate diseases associated with mitochondrial dysfunction and potentially enhance mitochondrial health. This review explores the therapeutic potential of PEVs in neurodegenerative and cardiovascular disorders, highlighting their role in restoring mitochondrial health. By examining recent advancements in PEVs research, we aim to shed light on novel strategies for utilizing PEVs as therapeutic agents. Our goal is to underscore the importance of further fundamental and applied research into PEVs-based interventions, as innovative tools for combating a wide range of diseases linked to mitochondrial dysfunction.

Comprehensive Comparison of Methods for Isolation of Extracellular Vesicles from Human Plasma

Extracellular vesicles (EVs) are a vital component in cell-cell communication and hold significant potential as biomarkers and therapeutic carriers. Having a reproducible and simple EV isolation method for small volumes of human plasma is essential for biomarker discovery. Although combining multiple methods has been a recent trend in its ability to minimize contamination, it is not ideal for clinical specimens due to the large sample number and small sample volume. This study compared EVs isolated from 100 μL of plasma by nine commonly used methods based on different principles, including centrifugation, polymer precipitation, size exclusion, electrostatic interaction, and affinity enrichment. The isolated EVs were characterized by particle size and number using nanoparticle tracking analysis, purity, and contaminants using Simple Western and overall proteomic profiles using bottom-up proteomics. Despite the same EV enrichment principle, individual methods isolated EVs exhibited distinct characteristics, likely due to variations in the physicochemical properties of materials used and specific protocols. Overall, all of the methods evaluated are reproducible. MagNet and MagCap methods result in purer EVs with the narrowest size distribution and the highest proteome coverage but modest yield. This is the first report on isolating EVs from 100 μL of plasma using nine different methods with detailed characterization.

Cannabidiol-Loaded Retinal Organoid-Derived Extracellular Vesicles Protect Oxidatively Stressed ARPE-19 Cells

Background/Objectives: Age-related macular degeneration (AMD) is the third leading cause of irreversible blindness in elderly individuals aged over 50 years old. Oxidative stress plays a crucial role in the etiopathogenesis of multifactorial AMD disease. The phospholipid bilayer EVs derived from the culture-conditioned medium of human induced pluripotent stem cell (hiPSC) differentiated retinal organoids aid in cell-to-cell communication, signaling, and extracellular matrix remodeling. The goal of the current study is to establish and evaluate the encapsulation of a hydrophobic compound, cannabidiol (CBD), into retinal organoid-derived extracellular vesicles (EVs) for potential therapeutic use in AMD. Methods: hiPSC-derived retinal organoid EVs were encapsulated with CBD via sonication (CBD-EVs), and structural features were elucidated using atomic force microscopy, nanoparticle tracking analysis, and small/microRNA (miRNA) sequencing. ARPE-19 cells and oxidative-stressed (H2O2) ARPE-19 cells treated with CBD-EVs were assessed for cytotoxicity, apoptosis (MTT assay), reactive oxygen species (DCFDA), and antioxidant proteins (immunohistochemistry and Western blot). Results: Distinct miRNA cargo were identified in early and late retinal organoid-derived EVs, implicating their roles in retinal development, differentiation, and functionality. The therapeutic effects of CBD-loaded EVs on oxidative-stressed ARPE-19 cells showed greater viability, decreased ROS production, downregulated expression of inflammation- and apoptosis-related proteins, and upregulated expression of antioxidants by Western blot and immunocytochemistry. Conclusions: miRNAs are both prognostic and predictive biomarkers and can be a target for developing therapy since they regulate RPE physiology and diseases. Our findings indicate that CBD-EVs could potentially alleviate the course of AMD by activating the targeted proteins linked to the adenosine monophosphate kinase (AMPK) pathway. Implicating the use of CBD-EVs represents a novel frontline to promote long-term abstinence from drugs and pharmacotherapy development in treating AMD.

Maternal plasma extracellular vesicles tsRNA as potential biomarkers for assessing preterm labor risk

BACKGROUND

Spontaneous preterm labor (PTL) accounts for approximately 70% of preterm births, posing significant risks to both maternal and neonatal health. Current predictive biomarkers lack sufficient reliability, underscoring the need for non-invasive and dependable indicators. Emerging research indicates that tRNA-derived small RNAs (tsRNAs) are involved in various diseases; however, their potential association with PTL remains underexplored.

METHODS

Bioinformatics analyses of public GEO datasets (PRJNA415953 and PRJNA428989) were conducted to identify tsRNAs associated with PTL. Validation was performed using plasma extracellular vesicles samples collected at 12 weeks of gestation from PTL patients (n = 45) and healthy controls (n = 38). Functional assays were used to assess the impact of tsRNA1 (tRNA-Gly-GCC-5p-tRF-921) on extravillous trophoblast (EVT) function, including apoptosis, migration, invasion, and endothelial-like tube formation in HTR8/SVneo cells. Transcriptomic sequencing was conducted to identify tsRNA1-mediated pathways, and DNA methylation patterns were predicted based on the transcriptomic data. Statistical significance was determined using Student's t-test.

RESULTS

Two tsRNAs, tsRNA1 and tsRNA3 (tRNA-Gly-GCC-5p-tR-half-368), were significantly upregulated in PTL patient samples compared to controls. Overexpression of tsRNA1 impaired EVT function, increased apoptosis, and altered DNA methylation profiles, implicating its critical role in PTL mechanisms.

CONCLUSIONS

This study identifies tsRNA1 as a key regulator of EVT dysfunction and placental pathology in PTL. The findings provide novel insights into the mechanistic role of tsRNAs in PTL and highlight tsRNA1 as a promising biomarker for early risk stratification and prediction of the condition.

CLINICAL TRIAL NUMBER

Not applicable.

Engineered dendritic cells-derived extracellular vesicles for cancer immunotherapy

Extracellular vesicles (EVs) have emerged as a cell-free therapeutic approach, garnering increasing attention for their potential to enhance the safety and efficacy of immunotherapy. This interest is primarily driven by the biocompatibility and cell/tissue tropism inherent to EVs, but also due to their reconfigurable content. This, termed as cargo, may comprise bioactive molecules as proteins, lipids, and nucleic acids that play a pivotal role in mediating intercellular communication. In particular, dendritic cells-derived extracellular vesicles (DC-EVs) facilitate the transfer of critical components, like antigens and immune-regulatory factors, and due to the expression of major histocompatibility complexes and co-stimulatory molecules on their surface can activate T cells, thereby modulating the immune response. Additionally, DC-EVs can be engineered to transport tumor-specific antigens, cytokines, or other agents in order to strength their immunotherapeutic potential, and even be used in vaccines formulation. In this review, the latest advancements in engineering DC-EVs to improve their immunotherapeutic potential is discussed in detail, while also addressing current challenges associated with DC-EVs therapies.