Search Results (180)

Extracellular vesicles, encompassing eukaryotic exosomes and bacterial outer membrane vesicles (OMVs), play multifaceted roles in mediating host–pathogen interactions. These nanoscale structures act as critical mediators of intercellular communication, transporting diverse bioactive cargo such as miRNAs, cytokines, proteins, and bacterial components. Exosomes contribute to host immunity by delivering antimicrobial agents and modulating inflammatory responses, but they can also be hijacked by pathogens to suppress defenses and promote persistent infection. OMVs, on the other hand, enable bacteria to disseminate virulence factors, deliver toxins directly into host cells, and modulate immune signaling. For example, exosomes from infected macrophages can stimulate dendritic cell activation and T-cell priming, whereas bacterial OMVs have been shown to suppress host immunity or trigger excessive inflammation depending on their molecular cargo. Importantly, OMVs facilitate horizontal gene transfer and nutrient exchange within microbial communities, thereby influencing microbiome composition and adaptation. Together, these complex dynamics position both exosomes and OMVs as central players in immunity and pathogenesis. This review synthesizes recent insights into how host- and pathogen-derived vesicles modulate infection biology and immune responses, while also exploring their potential as diagnostic biomarkers and therapeutic carriers, and discussing current limitations in their clinical translation. Full article

The brain and the immune system communicate in many ways and interact directly at neuroimmune interfaces at brain borders, such as hippocampus, choroid plexus, and gateway reflexes. The first part of this review described intercellular communication (synapses, extracellular vesicles, and tunneling nanotubes) during homeostasis and neuroimmunomodulation upon dysfunction. This second part compares spatial orientation, learning, and memory function in both systems. The hippocampus, deep in the medial temporal lobes of the brain, is reported to play a central role in all three functions. Its medial entorhinal cortex contains neuronal spatial cells (place cells, head direction cells, boundary vector cells, and grid cells) that facilitate spatial navigation and allow the construction of cognitive maps. Sensory input (about 100 megabytes per second) via engram neurons and top down and bottom up information processing between the temporal lobes and other lobes of the brain are described to facilitate learning and memory function. Output impulses leave the brain via approximately 1.5 million fibers, which connect to effector organs such as muscles and glands. Spatial orientation in the immune system is described to involve gradients of chemokines, chemokine receptors, and cell adhesion molecules. These facilitate immune cell interactions with other cells and the extracellular matrix, recirculation via lymphatic organs (lymph nodes, thymus, spleen, and bone marrow), and via lymphatic fluid, blood, cerebrospinal fluid, and tissues. Learning in the immune system is summarized to include recognition of exogenous antigens from the outside world as well as endogenous blood-borne antigens, including tumor antigens. This learning process involves cognate interactions through immune synapses and the distinction between self and non-self antigens. Immune education via vaccination helps the process of development of protective immunity. Examples are presented concerning the therapeutic potential of memory T cells, in particular those derived from bone marrow. Like in the brain, memory function in the immune system is described to be facilitated by priming (imprinting), training, clonal cooperation, and an integrated perception of objects. The discussion part highlights evolutionary aspects. Full article

Background/Objectives: Circulating tumor cells (CTCs) and large extracellular vesicles (LEVs) are key components of the liquid biopsy that provide minimally invasive access to tumor biology. A clinically relevant subset of CTCs coexpressing epithelial and immune markers (im.CTCs) has been described, yet the origin of this phenotype remains unclear. In this study, we investigated the cellular and molecular context underlying the emergence of immune marker expression on CTCs and LEVs. Methods: Using high-resolution immunofluorescence microscopy of patient-derived blood samples, we identified direct physical interactions between white blood cells (WBCs) and both im.CTCs and im.LEVs, exclusively in patients harboring im.CTCs. Results: In several cases, WBCs partially encapsulated CTCs and LEVs, and quantitative analysis revealed localized enrichment of immune membrane markers at the contact interface, distinguishing these events from random proximity. Proteomic profiling further identified CD4+ T cells as the predominant interacting immune cell type and confirmed the presence of CD45, CD3, and CD4 on the interacting CTCs and LEVs, matching their WBC counterparts. Conclusion: These findings support membrane transfer as a potential mechanism for the acquisition of immune markers by CTCs and LEVs and provide in vivo evidence of contact-dependent tumor-immune interactions in circulation with implications for immune modulation and clinical interpretation of the im.CTC phenotype. Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing in both prevalence and severity, highlighting the need for non-invasive biomarkers to assess disease activity. Extracellular vesicles (EVs), which carry molecular cargo from their cells of origin, hold promise as accessible biomarkers. We performed proteomic profiling of plasma-derived EVs from 70 patients with MASLD to identify protein signatures associated with key histological features (steatosis, metabolic dysfunction-associated steatohepatitis (MASH), and fibrosis). These proteins were subsequently correlated with magnetic resonance (MR)-based liver imaging. Plasma EV protein profile differed between mild (S1) and advanced steatosis (S3). H4C1, OIT3, and ANPEP were elevated in S3, while CCDC25 and KLHL41 were decreased (|log₂ fold change| > 1, p < 0.05). KLHL41 had a weak-to-moderate correlation with proton density fat fraction (PDFF) (R = −0.34, p = 0.016). GP1BA was upregulated in MASH (log₂ fold change = 1.13, p = 0.03) but showed weak correlation with cT1, an imaging parameter for steatohepatitis (R = 0.22, p = 0.173). In fibrosis, complement component 7 (C7) was elevated in advanced (≥F3) vs. mild fibrosis (<F2) (log₂ fold change = 0.95, adjusted p = 0.002) and correlated with MR elastography-derived liver stiffness (R = 0.38, p = 0.004). The AUC of C7 for differentiating <F2 vs. ≥F2 and <F3 vs. ≥F3 was 0.80 (95% CI: 0.69–0.91) and 0.83 (95% CI: 0.72–0.93), respectively. In conclusion, plasma EVs contain distinct protein signatures associated with steatosis, steatohepatitis, and fibrosis in MASLD. These preliminary findings support the potential utility of plasma EVs as non-invasive biomarkers and provide insights into disease pathophysiology. However, further validation in larger, independent cohorts is necessary to confirm these associations and establish their clinical relevance. Full article

Exosomes are extracellular vesicles that play a central role in mediating intercellular communication within the tumor microenvironment (TME). Cancer-derived exosomes carry proteins, nucleic acids, and lipids that reshape the phenotype and function of surrounding stromal and immune cells, thereby promoting tumor progression, angiogenesis, metastasis, and resistance to therapy. At the same time, exosomes derived from TME components, including macrophages, dendritic cells, B cells, T cells, fibroblasts, neutrophils, and NK cells, reciprocally influence tumor growth and immune evasion. These bidirectional interactions highlight exosomes as both drivers of tumor progression and regulators of antitumor immunity. In this review, we synthesize current evidence on the diverse mechanisms by which exosomes reprogram immune and stromal cells, with a focus on their dual roles in cancer biology. We also discuss emerging therapeutic strategies to inhibit exosome biogenesis, release, and function, underscoring their translational potential as novel targets for cancer diagnosis and treatment. Full article

We previously demonstrated that in BAP1-proficient pleural mesothelioma cells, CDKN2A is critical for mediating the response to selective EZH2 inhibition and highlighted a complex interplay between epigenetic regulation and the tumor immune microenvironment. In this study, we employed a quantitative proteomic mass spectrometry approach to assess alterations in protein expression following EZH2 inhibition in BAP1- and CDKN2A-proficient mesothelioma cells cultured as spheroids. Additionally, we analyzed extracellular vesicles (EVs), which were isolated through tangential flow filtration. Flow cytometric analysis and co-culture systems were used to characterize the effects of EVs on neutrophils. Upon EZH2 inhibition, we demonstrated RAB27b and CD63 upregulation and increased release of extracellular vesicles. We found that a brief exposure to EVs derived from EZH2 inhibitor-treated cells skewed naïve neutrophils toward a pro-tumor phenotype characterized by high levels of PD-L1 and MSLN (Mesothelin) expression on the surface. These EV-elicited neutrophils suppressed T cell proliferation while enhancing tumor cell growth. Moreover, we observed changes in the EV cargo derived from EZH2 inhibitor-treated spheroids. Our findings highlight the significant role of EVs in creating an immunosuppressive microenvironment, and underscore the urgent need for further investigation into the regulation of neutrophil biology and function in the PM. Full article

Connexin 26 (Cx26), a gap junction protein, is poorly understood in the context of cardiac milieu, including extracellular vesicles (EVs). Here, we report for the first time the presence of Cx26 on EVs obtained from human induced pluripotent stem cell-derived cardiomyocytes and human plasma. Using an in vitro model of oxidative stress and apoptosis in dH9c2 cardiomyocytes, we observed a significant decrease in Cx26 levels in EVs released by injured cells, accompanied by changes in EV concentration, particularly in exosomes. Our findings revealed that Cx26 modulates the selective loading of specific microRNAs, namely miR-1 and miR-30a, into EVs, suggesting a novel non-canonical, gap junction-independent role of Cx26 in EV-mediated cardiac signaling. Analysis of plasma EVs from healthy donors confirmed the presence of Cx26-positive EVs of cardiomyocyte origin, indicated by co-staining with cardiac troponin T. These findings suggest that further studies on the measurement of Cx26 on circulating EVs from patients with ischemic heart disease and heart failure are warranted to clarify its potential as a biomarker for cardiomyocyte injury in cardiomyopathies with oxidative stress and apoptosis. Full article

Background/Objectives: Trophoblast cell surface antigen 2 (Trop2), a transmembrane glycoprotein overexpressed in a broad spectrum of epithelial malignancies but minimally expressed in normal tissues, has emerged as a clinically relevant prognostic biomarker and therapeutic target, particularly in breast cancer. This study aims to develop an enhanced way of targeting Trop2 expression in tumors and blocking it using extracellular vesicles (EVs) bioengineered to express a nanobody sequence against Trop2 (NB60 E). Methods: Here, a plasmid construct was designed to express the Trop2 sequence, NB60, flanked with HA tag and myc epitope and a PDGFR transmembrane domain in the C-terminal region, and was transfected into HEK293T cells for EVs isolation. The potency of NB60 E to knock down Trop2 in letrozole-resistant breast cancer cells (LTLT-Ca and MDA-MB-468 cells) was initially investigated. Thereafter, the effects of NB60 E on the cell viability and downstream signaling pathway of Trop2 via MTT assay and Western blotting were determined. Lastly, we also examined whether NB60 E treatment in Jurkat T cells affects IL-6, TNF-α, and IL-2 cytokine production by enzyme-linked immunosorbent assay (ELISA). Results: Results revealed treatment with NB60 E significantly reduced surface Trop2 expression across both cell lines by 23.5 ± 1.5% in MDA-MB-468, and 61.5 ± 1.5% in LTLT-Ca, relative to the HEK293T-derived control EVs (HEK293T E). NB60 E treatment resulted in a marked reduction in LTLT-Ca cell viability by 52.8 ± 0.9% at 48 h post-treatment. This was accompanied by downregulation of key oncogenic signaling molecules: phosphorylated ERK1/2 (p-ERK 1/2) decreased by 30 ± 4%, cyclin D1 by 67 ± 11%, phosphorylated STAT3 (p-STAT3) by 71.8 ± 1.6%, and vimentin by 40.8 ± 1.4%. ELISA analysis revealed significant decreases in IL-6 (−57.5 ± 1.5%, 7.4 ± 0.35 pg/mL) and TNF-α (−32.1 ± 0.3%, 6.1 ± 1.2 pg/mL) levels, coordinated by an increase in IL-2 secretion (22.1 ± 2.7%, 49.2 ± 1.1 pg/mL). Quantitative analysis showed marked reductions in the number of nodes (−45 ± 4.4%), junctions (−55 ± 3.5%), and branch points (−38 ± 1.2%), indicating suppression of angiogenic capacity. In vivo experiment using near-infrared Cy7 imaging demonstrated rapid and tumor-selective accumulation of NB60 E within 4 h post-administration, followed by efficient systemic clearance by 24 h. The in vivo results demonstrate the effectiveness of NB60 E in targeting Trop2-enriched tumors while being efficiently cleared from the system, thus minimizing off-target interactions with normal cells. Lastly, Trop2 expression in LTLT-Ca tumor xenografts revealed a significant reduction of 41.0 ± 4% following NB60 E treatment, confirming efficient targeted delivery. Conclusions: We present a first-in-field NB60 E-grafted EV therapy that precisely homes to Trop2-enriched breast cancers, silences multiple growth-and-invasion pathways, blocks angiogenesis, and rewires cytokine crosstalk, achieving potent antitumor effects with self-clearing, biomimetic carriers. Our results here show promising potential for the use of NB60 E as anti-cancer agents, not only for letrozole-resistant breast cancer but also for other Trop2-expressing cancers. Full article

Extracellular vesicles (EVs) derived from bacteria are emerging as potent bioactive carriers that affect host immunity. Deinococcus radiodurans, an extremophilic bacterium with strong antioxidant capacity, produces EVs enriched in deinoxanthin (DX), a carotenoid with a reactive oxygen species–scavenging activity. Here, we assessed the antioxidant activity of D. radiodurans-derived EVs (R1-EVs) in biochemical assays and their immunomodulatory effects on dendritic cells (DCs). R1-EVs exhibited significantly higher antioxidant activity than EVs from a DX-deficient mutant strain (ΔcrtI-EVs), consistent with DX enrichment. Bone marrow-derived DCs treated with R1-EVs in the presence of lipopolysaccharide displayed reduced expression of surface maturation markers and pro-inflammatory cytokines, while interleukin-10 (IL-10) production and antigen uptake were preserved, indicating a tolerogenic phenotype. This tolerogenic program led to decreased proliferation and cytokine production in allogeneic CD4⁺ and CD8⁺ T cells. Mechanistically, R1-EVs inhibited mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) signaling pathways, key regulators of the DC activation. Importantly, IL-10 neutralization reversed these effects, restoring DC and T cell activation. Notably, ΔcrtI-EVs showed weaker antioxidant and immunoregulatory activities. Together, our findings identify R1-EVs as dual-functions, DX- and IL-10-dependent nanoplatform that integrates antioxidant and tolerogenic properties, with potential applications in inflammatory and autoimmune disease control. Full article

Doxorubicin (Dox) is not a first-line treatment for melanoma due to limited antitumor efficacy and dose-dependent cardiotoxicity. However, sublethal doses may trigger adaptive cellular responses that influence tumor progression and systemic toxicity. Small extracellular vesicles (EVs) are key mediators of intercellular communication and can carry bioactive molecules that modulate both the tumor microenvironment and distant tissues. This study investigates how sublethal Dox exposure alters EV biogenesis and cargo in A375 melanoma cells and explores the potential implications for cardiovascular function. We treated human A375 melanoma cells with 10 nM dox for 96 h. EVs were isolated using differential ultracentrifugation and size exclusion chromatography. Vesicle characterization included Immunocytochemistry for CD63, CD81, CD9, Rab7 and TSG101, scanning electron microscopy (SEM) Nanoparticle Tracking Analysis (NTA), and Western blotting for CD81 and CytC. We analyzed cytokine content using cytokine membrane arrays. Guinea pig cardiomyocytes were exposed to the isolated vesicles, and mitochondrial activity was evaluated using the MTT assay. Statistical analysis included t-tests, ANOVA, Cohen’s d, and R² and η². Dox exposure significantly increased EV production (13.6-fold; p = 0.000014) and shifted vesicle size distribution. CD81 expression was significantly upregulated (p = 0.0083), and SEM (microscopy) confirmed enhanced vesiculation. EVs from treated cells were enriched in TGF-β (p = 0.0134), VEGF, CXCL1, CXCL12, CCL5, IL-3, IL-4, IL-10, Galectin-3, and KITLG. Cardiomyocytes exposed to these vesicles showed a 2.3-fold reduction in mitochondrial activity (p = 0.0021), an effect absent when vesicles were removed. Bioinformatic analysis linked EV cargo to pathways involved in cardiac hypertrophy, inflammation, and fibrosis. As conclusion, sublethal Doxorubicin reprograms melanoma-derived EVs by enhancing their production and enriching their cargo with profibrotic and immunomodulatory mediators. These vesicles may contribute to tumor progression and cardiovascular physiopathology, suggesting that targeting EVs could improve therapeutic outcomes in cancer and cardiovascular disease. Full article

Uncontrolled and excessive inflammation could negatively impact embryo implantation, potentially leading to implantation failure or miscarriage. Small extracellular vesicles (sEVs) secreted by extravillous trophoblasts (EVTs) play a significant role in mediating the homeostasis at the maternal–fetal interface. In the present work we assessed the role of EVT-derived sEVs in the protection of the human blastocyst’s integrity and function in a microenvironment with excessive Th1-induced inflammation using the Sw71 blastocyst-like surrogate (Sw71 BLS) as a model of implanting a human embryo. Conditioned media from primary trophoblast-derived EVT cells were used as the source for sEVs’ isolation by precipitation. sEVs were characterized by TEM, IEM, and protein content. To simulate Th1-induced inflammation, we performed TCR stimulation and polyclonal activation of isolated T cells, which preferentially led to Th1 cytokine production. The use of the Sw71 spheroid model allowed us to monitor directly the damaging effect of high levels of Th1 cytokines on the ability of trophoblast cells to self-organize and migrate. The addition of EVT-sEVs unlocked the absolute migration capacity of the trophoblast cells in a healthy microenvironment. However, EVT-sEV treatment could not counteract the adverse effects of excessive Th1-mediated inflammation. This study provides a platform for further elucidation of the EVT-sEV dosage and potency for trophoblast functional recovery. Full article

Cell-based therapies emerge as potential treatment options for various debilitating diseases. Preclinical research and clinical studies involving cells increased exponentially in the past decade. In addition to cell-based approaches, the use of extracellular vesicles (EVs), which are released by nearly all cell types, emerged as a promising cell-free alternative. Those approaches are also being explored in the field of ophthalmology. Several clinical trials involving EVs are underway to develop potential treatments for advanced ocular surface diseases, including corneal disorders, injuries, and dry eye disease. The cargo carried by EVs has been shown to include a diverse array of functional molecules such as transcription factors, cytokines, growth factors, mRNA, tRNA, rRNA, miRNA, and fragments of dsDNA. While the molecular composition of EVs is already well characterised, the specific activity of these molecules upon delivery to recipient cells remains poorly understood. In this review, we summarise recent studies investigating the bioactive molecules within EVs shown to influence or modulate cellular activity on the ocular surface. Among these, various miRNAs have most commonly been identified as therapeutic agents targeting distinct molecular pathways. The EVs studied were predominantly derived from various mesenchymal stem cells. Full article

Background/Objectives: Extracellular vesicles (EVs) are involved in cell-to-cell communication and delivery of signaling molecules and represent an interesting approach in targeted therapy. This project focused on EV-mediated facilitation and cell-specific delivery of effector antimiR molecules carried by biologically produced gold nanoparticles (AuNPs). Methods: First, we loaded EVs derived from cancer cells 4T1 with AuNPs-antimiR. The AuNPs were also decorated with or without transferrin (Tf) molecules. We examined parental cell-specific delivery of the AuNPs-Tf-antimiR within monocultures as well as co-cultures in vitro. Subsequently, we used autologous EVs containing AuNPs-Tf-antimiR to target tumor cells in a xenograft tumor model in vivo. Efficacy of the antimir transfer was assessed by qPCR and apoptosis assessment. Results: In vitro, EVs loaded with AuNPs-antimiR were internalized only by the parental cells and the AuNPs-antimiR transfer was successful and effective only in EVs that were decorated with Tf. We achieved effective delivery of the antimiR molecule into cancer cells in vivo, which was proved by specific silencing of the target oncogenic miRNA as well as induction of cancer cells apoptosis. Conclusions: EVs represent an interesting and potent way for targeted cargo delivery and personalized medicine. On the other hand, there are various safety and efficacy challenges that remain to be addressed. Full article

Background and Significances: In patients with Epstein–Barr virus-driven hemophagocytic lymphohistiocytosis (EBV-HLH), identifying the underlying cause poses a significant diagnostic challenge. HLH may precede overt disease, and early directed treatment for HLH can obscure histopathological findings. A liquid biopsy enables the detection of tumor-derived DNA from various sources, including cell-free DNA, circulating tumor cells, extracellular vesicles, and tumor-educated platelets, and might aid in this setting. Case Presentation: This case presents a young patient with EBV-HLH, in which genomic analysis of tumor-derived DNA from circulating tumor cells led to the diagnosis of an EBV-positive NK/T-cell lymphoma—where conventional tissue biopsies had failed. Conclusions: This report underscores the potential of the liquid biopsy as a valuable diagnostic tool in complex cases of EBV-HLH. Full article

Adipose stem cells (ASCs) are a subset of mesenchymal stem cells with validated immunomodulatory and regenerative capabilities that make them attractive tools for treating neurodegenerative disorders, such as multiple sclerosis (MS). Several studies conducted on experimental autoimmune encephalomyelitis (EAE), the animal model of MS, have clearly shown a therapeutic effect of ASCs. However, controversial data on their efficacy were obtained from I- and II-phase clinical trials in MS patients, highlighting standardization issues and limited data on long-term safety. In this context, ASC-derived extracellular vesicles from (ASC-EVs) represent a safer, more reproducible alternative for EAE and MS treatment. Moreover, their physical characteristics lend themselves to a non-invasive, efficient, and easy handling of intranasal delivery. Using an in vitro setting, we first verified ASC-EVs’ ability to cross the human nasal epithelium under an inflammatory milieu. Magnetic resonance corroborated these data in vivo in intranasally treated MOG35-55-induced EAE mice, showing a preferential accumulation of ASC-EVs in brain-inflamed lesions compared to a stochastic distribution in healthy control mice. Moreover, intranasal treatment of ASC-EVs at the EAE onset led to a long-term therapeutic effect using two different experimental protocols. A marked reduction in T cell infiltration, demyelination, axonal damage, and cytokine production were correlated to EAE amelioration in ASC-EV-treated mice compared to control mice, highlighting the immunomodulatory and neuroprotective roles exerted by ASC-EVs during EAE progression. Overall, our study paves the way for promising clinical applications of self-administered ASC-EV intranasal treatment in CNS disorders, including MS. Full article