Subpopulations of extracellular vesicles from human metastatic melanoma tissue identified by quantitative proteomics after optimized isolation

One-step and label-free ratiometric fluorescence assay for the detection of plasma exosome towards cancer diagnosis

Exosomes are closely associated with tumor development and are regarded as viable biomarkers for cancer. Here, a ratiometric fluorescence method was proposed for the one-step and label-free detection of plasma exosomes. A bicolor streptavidin magnetic beads were specifically created with an immobilized Cy5-labeled hairpin aptamer for CD63 (Cy5-Apt) on its surface to identify exosome, and a green color SYBR Green I (SGI) embedded in the stem of Cy5-Apt to respond to exosomes. After exosome capture, the Cy5-Apt could undergo a conformational shift and release the encapsulated SGI, allowing exosome measurement based on the fluorescence ratio of Cy5 and SGI. The enrichment, separation and detection of exosomes in proposed method could be completed in one step (30 min), which is a significant improvement over previous method. Furthermore, the use of ratiometric fluorescence and magnetic separation allows for exosome enrichment and interference elimination from complex matrices, improving accuracy and sensitivity. Particularly, the assay could detect exosomes in plasma and has potential to distinguish lung cancer patients from healthy volunteers with an area under the receiver operator characteristic curve of 0.85. Besides, the study provided an efficient method for analyzing the various divisions of exosomes by merely modifying the aptamer, which holds great promise for point-of-care applications.

The tumour-derived extracellular vesicle proteome varies by endometrial cancer histology and is confounded by an obesogenic environment

Endometrial cancer, the most common gynaecological cancer worldwide, is closely linked to obesity and metabolic diseases, particularly in younger women. New circulating biomarkers have the potential to improve diagnosis and treatment selections, which could significantly improve outcomes. Our approach focuses on extracellular vesicle (EV) biomarker discovery by directly profiling the proteome of EVs enriched from frozen biobanked endometrial tumours. We analysed nine tissue samples to compare three clinical subgroups-low BMI (Body Mass Index) Endometrioid, high BMI Endometrioid, and Serous (any BMI)-identifying proteins related to histological subtype, BMI, and shared secreted proteins. Using collagenase digestion and size exclusion chromatography, we successfully enriched generous quantities of EVs (range 204.8-1291.0 µg protein: 1.38 × 1011-1.10 × 1012 particles), characterised by their size (∼150 nm), expression of EV markers (CD63/81), and proposed endometrial cancer markers (L1CAM, ANXA2). Mass spectrometry-based proteomic profiling identified 2075 proteins present in at least one of the 18 samples. Compared to cell lysates, EVs were successfully depleted for mitochondrial and blood proteins and enriched for common EV markers and large secreted proteins. Further analysis highlighted significant differences in EV protein profiles between the high BMI subgroup and others, underlining the impact of comorbidities on the EV secretome. Interestingly, proteins differentially abundant in tissue subgroups were largely not also differential in matched EVs. This research identified secreted proteins known to be involved in endometrial cancer pathophysiology and proposed novel diagnostic biomarkers (EIF6, MUC16, PROM1, SLC26A2).

Research advances of tissue-derived extracellular vesicles in cancers

BACKGROUND

Extracellular vesicles (EVs) can mediate cell-to-cell communication and affect various physiological and pathological processes in both parent and recipient cells. Currently, extensive research has focused on the EVs derived from cell cultures and various body fluids. However, insufficient attention has been paid to the EVs derived from tissues. Tissue EVs can reflect the microenvironment of the specific tissue and the cross-talk of communication among different cells, which can provide more accurate and comprehensive information for understanding the development and progression of diseases.

METHODS

We review the state-of-the-art technologies involved in the isolation and purification of tissue EVs. Then, the latest research progress of tissue EVs in the mechanism of tumor occurrence and development is presented. And finally, the application of tissue EVs in the clinical diagnosis and treatment of cancer is anticipated.

RESULTS

We evaluate the strengths and weaknesses of various tissue processing and EVs isolation methods, and subsequently analyze the significance of protein characterization in determining the purity of tissue EVs. Furthermore, we focus on outlining the importance of EVs derived from tumor and adipose tissues in tumorigenesis and development, as well as their potential applications in early tumor diagnosis, prognosis, and treatment.

CONCLUSION

When isolating and characterizing tissue EVs, the most appropriate protocol needs to be specified based on the characteristics of different tissues. Tissue EVs are valuable in the diagnosis, prognosis, and treatment of tumors, and the potential risks associated with tissue EVs need to be considered as therapeutic agents.

Most recent advances and applications of extracellular vesicles in tackling neurological challenges

Over the past few decades, there has been a notable increase in the global burden of central nervous system (CNS) diseases. Despite advances in technology and therapeutic options, neurological and neurodegenerative disorders persist as significant challenges in treatment and cure. Recently, there has been a remarkable surge of interest in extracellular vesicles (EVs) as pivotal mediators of intercellular communication. As carriers of molecular cargo, EVs demonstrate the ability to traverse the blood-brain barrier, enabling bidirectional communication. As a result, they have garnered attention as potential biomarkers and therapeutic agents, whether in their natural form or after being engineered for use in the CNS. This review article aims to provide a comprehensive introduction to EVs, encompassing various aspects such as their diverse isolation methods, characterization, handling, storage, and different routes for EV administration. Additionally, it underscores the recent advances in their potential applications in neurodegenerative disorder therapeutics. By exploring their unique capabilities, this study sheds light on the promising future of EVs in clinical research. It considers the inherent challenges and limitations of these emerging applications while incorporating the most recent updates in the field.

Extracellular Vesicles and Their Correlation with Inflammatory Factors in an Experimental Model of Steatotic Liver Disease Associated with Metabolic Dysfunction

Background/Aims: Extracellular vesicles (EVs) are promising as a biomarker of metabolic dysfunction associated steatotic liver disease (MASLD). The objective is to study EVs and their involvement in MASLD concerning the disease's pathogenesis and progression characteristics. Methods: Male adult Sprague Dawley rats were randomly assigned into two experimental models of MASLD: MASLD-16 and MASLD-28, animals received a choline-deficient high-fat diet (CHFD) and Control-16 and Control-28, animals received a standard diet (SD) for 16 and 28 weeks, respectively. Biological samples from these animal models were used, as well as previously registered variables. EVs from hepatic tissue were characterized using confocal microscopy. EVs were isolated through differential ultracentrifugation from serum and characterized using NanoSight. The data from the EVs were correlated with biochemical, molecular, and histopathological parameters. Results: Liver EVs were identified through the flotillin-1 protein. EVs were isolated from the serum of all groups. There was a decrease of EVs concentration in MASLD-28 in comparison with Control-28 (P < 0.001) and a significant increase in EVs concentration in Control-28 compared with Control-16 (P < 0.001). There was a strong correlation between serum EVs concentration with hepatic gene expression of interleukin (Il)6 (r2 = 0.685, P < 0.05), Il1b (r2 = 0.697, P < 0.05) and tumor necrosis factor-alpha (Tnfa; r2 = 0.636, P < 0.05) in MASLD-16. Moreover, there was a strong correlation between serum EVs size and Il10 in MASLD-28 (r2 = 0.762, P < 0.05). Conclusion: The concentration and size of EVs correlated with inflammatory markers, suggesting their involvement in the systemic circulation, cellular communication, and development and progression of MASLD, demonstrating that EVs have the potential to serve as noninvasive biomarkers for MASLD diagnosis and prognosis.

Exosomes define a local and systemic communication network in healthy pancreas and pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC), a lethal disease, requires a grasp of its biology for effective therapies. Exosomes, implicated in cancer, are poorly understood in living systems. Here we use the genetically engineered mouse model (ExoBow) to map the spatiotemporal distribution of exosomes from healthy and PDAC pancreas in vivo to determine their biological significance. We show that, within the PDAC microenvironment, cancer cells establish preferential communication routes through exosomes with cancer associated fibroblasts and endothelial cells. The latter being a conserved event in the healthy pancreas. Inhibiting exosomes secretion in both scenarios enhances angiogenesis, underscoring their contribution to vascularization and to cancer. Inter-organ communication is significantly increased in PDAC with specific organs as most frequent targets of exosomes communication occurring in health with the thymus, bone-marrow, brain, and intestines, and in PDAC with the kidneys, lungs and thymus. In sum, we find that exosomes mediate an organized intra- and inter- pancreas communication network with modulatory effects in vivo.

Size-exclusion chromatography combined with DIA-MS enables deep proteome profiling of extracellular vesicles from melanoma plasma and serum

Extracellular vesicles (EVs) are important players in melanoma progression, but their use as clinical biomarkers has been limited by the difficulty of profiling blood-derived EV proteins with high depth of coverage, the requirement for large input amounts, and complex protocols. Here, we provide a streamlined and reproducible experimental workflow to identify plasma- and serum- derived EV proteins of healthy donors and melanoma patients using minimal amounts of sample input. SEC-DIA-MS couples size-exclusion chromatography to EV concentration and deep-proteomic profiling using data-independent acquisition. From as little as 200 µL of plasma per patient in a cohort of three healthy donors and six melanoma patients, we identified and quantified 2896 EV-associated proteins, achieving a 3.5-fold increase in depth compared to previously published melanoma studies. To compare the EV-proteome to unenriched blood, we employed an automated workflow to deplete the 14 most abundant proteins from plasma and serum and thereby approximately doubled protein group identifications versus native blood. The EV proteome diverged from corresponding unenriched plasma and serum, and unlike the latter, separated healthy donor and melanoma patient samples. Furthermore, known melanoma markers, such as MCAM, TNC, and TGFBI, were upregulated in melanoma EVs but not in depleted melanoma plasma, highlighting the specific information contained in EVs. Overall, EVs were significantly enriched in intact membrane proteins and proteins related to SNARE protein interactions and T-cell biology. Taken together, we demonstrated the increased sensitivity of an EV-based proteomic workflow that can be easily applied to larger melanoma cohorts and other indications.

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

Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EV nomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its 'Minimal Information for Studies of Extracellular Vesicles', which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly.

NOP16 promotes hepatocellular carcinoma progression and triggers EMT through the Keap1-Nrf2 signaling pathway

BACKGROUND

Nucleolar protein 16 (NOP16) is present in the protein complex of the nucleolus. The NOP16 promoter contains a c-Myc binding site, and the transcriptional regulation by c-Myc directly regulates NOP16 expression levels.

OBJECTIVE

Dysregulation of NOP 16 is currently reported in only a small number of cancers. In this study, the expression profile of NOP 16 in hepatocellular carcinoma (LIHC) and its clinical significance were analyzed.

METHODS

NOP16 expression in hepatocellular carcinoma (LIHC) and its relationship with the clinical characters of LIHC were examined using the Cancer Genome Atlas (TCGA), the Gene Expression comprehensive database (GEO), Kaplan-Meier survival analysis, univariate Cox analysis, multivariate Cox analysis, ROC curve analysis of KEGG enrichment, GSEA enrichment, in vitro experiments (e.g., siRNA interference of NOP16 expression in hepatoma cells, Keap1-Nrf2 pathway, cell cycle, cell apoptosis and Transwell assays), and LIHC single-cell sequencing (scRNA).

RESULTS

Pan-cancer analysis revealed that NOP16 was highly expressed in 20 cancer types, including LIHC, and high NOP16 expression was an independent adverse prognostic factor in LIHC patients. The expression levels of NOP16 mRNA and protein were significantly increased in tumour tissues of LIHC patients compared to normal tissues. The functions of co-expressed genes were primarily enriched in the cell cycle and reactive oxygen species metabolism. The experimental results showed that knockdown of NOP16 activated the Keap/Nrf2 signalling pathway and inhibited the invasion, migration, and EMT progression of LIHC cells. LIHC scRNA-seq data showed that NOP16 was primarily expressed in T lymphocytes.

CONCLUSIONS

NOP16 promoted cancer development in LIHC and caused an imbalance in Keap/Nrf2 signalling, which subsequently caused the aberrant expression of genes typical for EMT, cell cycle progression and apoptosis. NOP16 is a potential prognostic marker and therapeutic target for hepatocellular carcinoma progression.

Heat inactivation of foetal bovine serum performed after EV-depletion influences the proteome of cell-derived extracellular vesicles

The release of extracellular vesicles (EVs) in cell cultures as well as their molecular cargo can be influenced by cell culture conditions such as the presence of foetal bovine serum (FBS). Although several studies have evaluated the effect of removing FBS-derived EVs by ultracentrifugation (UC), less is known about the influence of FBS heat inactivation (HI) on the cell-derived EVs. To assess this, three protocols based on different combinations of EV depletion by UC and HI were evaluated, including FBS ultracentrifuged but not heat inactivated (no-HI FBS), FBS heat inactivated before EV depletion (HI-before EV-depl FBS), and FBS heat inactivated after EV depletion (HI-after EV-depl FBS). We isolated large (L-EVs) and small EVs (S-EVs) from FBS treated in the three different ways, and we found that the S-EV pellet from HI-after EV-depl FBS was larger than the S-EV pellet from no-HI FBS and HI-before EV-depl FBS. Transmission electron microscopy, protein quantification, and particle number evaluation showed that HI-after EV-depl significantly increased the protein amount of S-EVs but had no significant effect on L-EVs. Consequently, the protein quantity of S-EVs isolated from three cell lines cultured in media supplemented with HI-after EV-depl FBS was significantly increased. Quantitative mass spectrometry analysis of FBS-derived S-EVs showed that the EV protein content was different when FBS was HI after EV depletion compared to EVs isolated from no-HI FBS and HI-before EV-depl FBS. Moreover, we show that several quantified proteins could be ascribed to human origin, thus demonstrating that FBS bovine proteins can mistakenly be attributed to human cell-derived EVs. We conclude that HI of FBS performed after EV depletion results in changes in the proteome, with molecules that co-isolate with EVs and can contaminate EVs when used in subsequent cell cultures. Our recommendation is, therefore, to always perform HI of FBS prior to EV depletion.

Prostate cancer-derived small extracellular vesicle proteins: the hope in diagnosis, prognosis, and therapeutics

Current diagnostic tools for prostate cancer (PCa) diagnosis and risk stratification are insufficient. The hidden onset and poor efficacy of traditional therapies against metastatic PCa make this disease a heavy burden in global men's health. Prostate cancer-derived extracellular vesicles (PCDEVs) have garnered attention in recent years due to their important role in communications in tumor microenvironment. Recent advancements have demonstrated PCDEVs proteins play an important role in PCa invasion, progression, metastasis, therapeutic resistance, and immune escape. In this review, we briefly discuss the applications of sEV proteins in PCa diagnosis and prognosis in liquid biopsy, focus on the roles of the PCa-derived small EVs (sEVs) proteins in tumor microenvironment associated with cancer progression, and explore the therapeutic potential of sEV proteins applied for future metastatic PCa therapy.

Integrated transcriptomics, proteomics, and functional analysis to characterize the tissue-specific small extracellular vesicle network of breast cancer

Small extracellular vesicles (sEVs) are essential mediators of intercellular communication within the tumor microenvironment (TME). Although the biological features of sEVs have been characterized based on in vitro culture models, recent evidence indicates significant differences between sEVs derived from tissue and those derived from in vitro models in terms of both content and biological function. However, comprehensive comparisons and functional analyses are still limited. Here, we collected sEVs from breast cancer tissues (T-sEVs), paired normal tissues (N-sEVs), corresponding plasma (B-sEVs), and tumor organoids (O-sEVs) to characterize their transcriptomic and proteomic profiles. We identified the actual cancer-specific sEV signatures characterized by enriched cell adhesion and immunomodulatory molecules. Furthermore, we revealed the significant contribution of cancer-associated fibroblasts in the sEV network within the TME. In vitro model-derived sEVs did not entirely inherit the extracellular matrix- and immunity regulation-related features of T-sEVs. Also, we demonstrated the greater immunostimulatory ability of T-sEVs on macrophages and CD8+ T cells compared to O-sEVs. Moreover, certain sEV biomarkers derived from noncancer cells in the circulation exhibited promising diagnostic potential. This study provides valuable insights into the functional characteristics of tumor tissue-derived sEVs, highlighting their potential as diagnostic markers and therapeutic agents for breast cancer.

Three-dimensional reconstruction of interstitial extracellular vesicles in human liver as determined by electron tomography

Extracellular vesicles (EVs) are lipid bilayer nanoparticles involved in cell-cell communication that are released into the extracellular space by all cell types. The cargo of EVs includes proteins, lipids, nucleic acids, and metabolites reflecting their cell of origin. EVs have recently been isolated directly from solid tissues, and this may provide insights into how EVs mediate communication between cells in vivo. Even though EVs have been isolated from tissues, their point of origin when they are in the interstitial space has been uncertain. In this study, we performed three-dimensional (3D) reconstruction using transmission electron tomography of metastatic and normal liver tissues with a focus on the presence of EVs in the interstitium. After chemical fixation of the samples and subsequent embedding of tissue pieces in resin, ultrathin slices (300 nm) were cut and imaged on a 120 ekV transmission electron microscopy as a tilt series (a series of subsequent images tilted at different angles). These were then computationally illustrated in a 3D manner to reconstruct the imaged tissue volume. We identified the cells delimiting the interstitial space in both types of tissues, and small distinct spherical structures with a diameter of 30-200 nm were identified between the cells. These round structures appeared to be more abundant in metastatic tissue compared to normal tissue. We suggest that the observed spherical structures in the interstitium of the metastatic and non-metastatic liver represent EVs. This work thus provides the first 3D visualization of EVs in human tissue.

Proteomics provides insights into the theranostic potential of extracellular vesicles

Extracellular vesicles (EVs) encompass a diverse range of membranous structures derived from cells, including exosomes and microvesicles. These vesicles are present in biological fluids and play vital roles in various physiological and pathological processes. They facilitate intercellular communication by enabling the exchange of proteins, lipids, and genetic material between cells. Understanding the cellular processes that govern EV biology is essential for unraveling their physiological and pathological functions and their potential clinical applications. Despite significant advancements in EV research in recent years, there is still much to learn about these vesicles. The advent of improved mass spectrometry (MS)-based techniques has allowed for a deeper characterization of EV protein composition, providing valuable insights into their roles in different physiological and pathological conditions. In this chapter, we provide an overview of proteomics studies conducted to identify the protein contents of EVs, which contribute to their therapeutic and pathological features. We also provided evidence on the potential of EV proteome contents as biomarkers for early disease diagnosis, progression, and treatment response, as well as factors that influence their composition. Additionally, we discuss the available databases containing information on EV proteome contents, and finally, we highlight the need for further research to pave the way toward their utilization in clinical settings.

Cellular and Molecular Connections Between Bone Fracture Healing and Exosomes

Fracture healing is a multifaceted process that requires various phases and intercellular interactions. In recent years, investigations have been conducted to assess the feasibility of utilizing exosomes, small extracellular vesicles (EVs), to enhance and accelerate the healing process. Exosomes serve as a cargo transport platform, facilitating intercellular communication, promoting the presentation of antigens to dendritic cells, and stimulating angiogenesis. Exosomes have a special structure that gives them a special function, especially in the healing process of bone injuries. This article provides an overview of cellular and molecular processes associated with bone fracture healing, as well as a survey of existing exosome research in this context. We also discuss the potential use of exosomes in fracture healing, as well as the obstacles that must be overcome to make this a viable clinical practice.

Microvesicles-hydrogel breaks the cycle of cellular senescence by improving mitochondrial function to treat osteoarthritis

BACKGROUND

Osteoarthritis (OA) is an age-related disease characterised by the accumulation of senescent chondrocytes, which drives its pathogenesis and progression. Senescent cells exhibit distinct features, including mitochondrial dysfunction and the excessive accumulation and release of reactive oxygen species (ROS), which are highly correlated and lead to a vicious cycle of increasing senescent cells. Stem cell therapy has proven effective in addressing cellular senescence, however, it still has issues such as immune rejection and ethical concerns. Microvesicles (MVs) constitute the primary mechanism through which stem cell therapy exerts its effects, offering a cell-free approach that circumvents these risks and has excellent anti-ageing potential. Nonetheless, MVs have a short in vivo half-life, and their secretion composition varies considerably under diverse conditions. This study aims to address these issues by constructing a ROS-responsive hydrogel loaded with pre-stimulant MVs. Through responding to ROS levels this hydrogel intelligently releases MVs, and enhancing mitochondrial function in chondrocytes to improving cellular senescence.

RESULT

We employed Interferon-gamma (IFN-γ) as a stem cell-specific stimulus to generate IFN-γ-microvesicles (iMVs) with enhanced anti-ageing effects. Simultaneously, we developed a ROS-responsive carrier utilising 3-aminophenylboronic acid (APBA)-modified silk fibroin (SF) and polyvinyl alcohol (PVA). This carrier served to protect MVs, prolong longevity, and facilitate intelligent release. In vitro experiments demonstrated that the Hydrogel@iMVs effectively mitigated cell senescence, improved mitochondrial function, and enhanced cellular antioxidant capacity. In vivo experiments further substantiated the anti-ageing capabilities of the Hydrogel@iMVs.

CONCLUSION

The effect of MVs can be significantly enhanced by appropriate pre-stimulation and constructing a suitable carrier. Therefore, we have developed a ROS-responsive hydrogel containing IFN-γ pre-stimulated iMVs to target the characteristics of ageing chondrocytes in OA for therapeutic purposes. Overall, this novel approach effectively improving mitochondrial dysfunction by regulating the balance between mitochondrial fission and fusion, and the accumulation of reactive oxygen species was reduced, finally, alleviates cellular senescence, offering a promising therapeutic strategy for OA.

Lineage specific extracellular vesicle-associated protein biomarkers for the early detection of high grade serous ovarian cancer

High grade serous ovarian carcinoma (HGSOC) accounts for ~ 70% of ovarian cancer cases. Non-invasive, highly specific blood-based tests for pre-symptomatic screening in women are crucial to reducing the mortality associated with this disease. Since most HGSOCs typically arise from the fallopian tubes (FT), our biomarker search focused on proteins found on the surface of extracellular vesicles (EVs) released by both FT and HGSOC tissue explants and representative cell lines. Using mass spectrometry, 985 EV proteins (exo-proteins) were identified that comprised the FT/HGSOC EV core proteome. Transmembrane exo-proteins were prioritized because these could serve as antigens for capture and/or detection. With a nano-engineered microfluidic platform, six newly discovered exo-proteins (ACSL4, IGSF8, ITGA2, ITGA5, ITGB3, MYOF) plus a known HGSOC associated protein, FOLR1 exhibited classification performance ranging from 85 to 98% in a case-control study using plasma samples representative of early (including stage IA/B) and late stage (stage III) HGSOCs. Furthermore, by a linear combination of IGSF8 and ITGA5 based on logistic regression analysis, we achieved a sensitivity of 80% with 99.8% specificity and a positive predictive value of 13.8%. Importantly, these exo-proteins also can accurately discriminate between ovarian and 12 types of cancers commonly diagnosed in women. Our studies demonstrate that these lineage-associated exo-biomarkers can detect ovarian cancer with high specificity and sensitivity early and potentially while localized to the FT when patient outcomes are more favorable.

Tissue-derived extracellular vesicles in cancer progression: mechanisms, roles, and potential applications

Extracellular vesicles (EVs) are small lipid bilayer-enclosed vesicles that mediate vital cellular communication by transferring cargo between cells. Among these, tissue-derived extracellular vesicles (Ti-EVs) stand out due to their origin from the tissue microenvironment, providing a more accurate reflection of changes in this setting. This unique advantage makes Ti-EVs valuable in investigating the intricate relationship between extracellular vesicles and cancer progression. Despite considerable research efforts exploring the association between Ti-EVs and cancers, a comprehensive clustering or grouping of these studies remains lacking. In this review, we aim to fill this gap by presenting a comprehensive synthesis of the mechanisms underlying Ti-EV generation, release, and transport within cancer tissues. Moreover, we delve into the pivotal roles that Ti-EVs play in cancer progression, shedding light on their potential as diagnostic and therapeutic tools. The review culminates in the construction of a comprehensive functional spectrum of Ti-EVs, providing a valuable reference for future research endeavors. By summarizing the current state of knowledge on Ti-EVs and their significance in tumor biology, this work contributes to a deeper understanding of cancer microenvironment dynamics and opens up avenues for harnessing Ti-EVs in diagnostic and therapeutic applications.

Immune capture and protein profiling of small extracellular vesicles from human plasma

Extracellular vesicles (EVs), the key players in inter-cellular communication, are produced by all cell types and are present in all body fluids. Analysis of the proteome content is an important approach in structural and functional studies of these vesicles. EVs circulating in human plasma are heterogeneous in size, cellular origin, and functions. This heterogeneity and the potential presence of contamination with plasma components such as lipoprotein particles and soluble plasma proteins represent a challenge in profiling the proteome of EV subsets by mass spectrometry. An immunocapture strategy prior to mass spectrometry may be used to isolate a homogeneous subpopulation of small EVs (sEV) with a specific endocytic origin from plasma or other biofluids. Immunocapture selectively separates EV subpopulations in biofluids based on the presence of a unique protein carried on the vesicle surface. The advantages and disadvantages of EV immune capture as a preparative step for mass spectrometry are discussed.

Recent advances in exosomal non-coding RNA-based therapeutic approaches for photoaging

BACKGROUND

Photoaging is a degenerative biological process that affects the quality of life. It is caused by environmental factors including ultraviolet radiation (UVR), deep skin burns, smoking, active oxygen, chemical substances, and trauma. Among them, UVR plays a vital role in the aging process.

AIM

With the continuous development of modern medicine, clinical researchers have investigated novel approaches to treat aging. In particular, mesenchymal stem cells (MSCs), non-coding RNAs are involved in various physiological processes have broad clinical application as they have the advantages of convenient samples, abundant sources, and avoidable ethical issues.

METHODS

This article reviews research progress on five types of stem cell, exosomes, non-coding RNA in the context of photoaging treatment: adipose-derived stem cell, human umbilical cord MSCs, epidermal progenitor cells, keratinocyte stem cells, and hair follicle stem cells (HFSCs). It also includes stem cell related exosomes and their non-coding RNA research.

RESULTS

The results have clinical guiding significance for prevention and control of the onset and development of photoaging. It is found that stem cells secrete cytokines, cell growth factors, non-coding RNA, exosomes and proteins to repair aging skin tissues and achieve skin rejuvenation. In particular, stem cell exosomes and non-coding RNA are found to have significant research potential, as they possess the benefits of their source cells without the disadvantages which include immune rejection and granuloma formation.

Extracellular Vesicle Heterogeneity and Its Impact for Regenerative Medicine Applications

Extracellular vesicles (EVs) are cell-derived membrane-enclosed particles that are involved in physiologic and pathologic processes. EVs are increasingly being studied for therapeutic applications in the field of regenerative medicine. Therapeutic application of stem cell-derived EVs has shown great potential to stimulate tissue repair. However, the exact mechanisms through which they induce this effect have not been fully clarified. This may to a large extent be attributed to a lack of knowledge on EV heterogeneity. Recent studies suggest that EVs represent a heterogeneous population of vesicles with distinct functions. The heterogeneity of EVs can be attributed to differences in their biogenesis, and as such, they can be classified into distinct populations that can then be further subcategorized into various subpopulations. A better understanding of EV heterogeneity is crucial for elucidating their mechanisms of action in tissue regeneration. This review provides an overview of the latest insights on EV heterogeneity related to tissue repair, including the different characteristics that contribute to such heterogeneity and the functional differences among EV subtypes. It also sheds light on the challenges that hinder clinical translation of EVs. Additionally, innovative EV isolation techniques for studying EV heterogeneity are discussed. Improved knowledge of active EV subtypes would promote the development of tailored EV therapies and aid researchers in the translation of EV-based therapeutics to the clinic. SIGNIFICANCE STATEMENT: Within this review we discuss the differences in regenerative properties of extracellular vesicle (EV) subpopulations and implications of EV heterogeneity for development of EV-based therapeutics. We aim to provide new insights into which aspects are leading to heterogeneity in EV preparations and stress the importance of EV heterogeneity studies for clinical applications.

Context-specific regulation of extracellular vesicle biogenesis and cargo selection

To coordinate, adapt and respond to biological signals, cells convey specific messages to other cells. An important aspect of cell-cell communication involves secretion of molecules into the extracellular space. How these molecules are selected for secretion has been a fundamental question in the membrane trafficking field for decades. Recently, extracellular vesicles (EVs) have been recognized as key players in intercellular communication, carrying not only membrane proteins and lipids but also RNAs, cytosolic proteins and other signalling molecules to recipient cells. To communicate the right message, it is essential to sort cargoes into EVs in a regulated and context-specific manner. In recent years, a wealth of lipidomic, proteomic and RNA sequencing studies have revealed that EV cargo composition differs depending upon the donor cell type, metabolic cues and disease states. Analyses of distinct cargo 'fingerprints' have uncovered mechanistic linkages between the activation of specific molecular pathways and cargo sorting. In addition, cell biology studies are beginning to reveal novel biogenesis mechanisms regulated by cellular context. Here, we review context-specific mechanisms of EV biogenesis and cargo sorting, focusing on how cell signalling and cell state influence which cellular components are ultimately targeted to EVs.

Towards optimised extracellular vesicle proteomics from cerebrospinal fluid

The proteomic profile of extracellular vesicles (EVs) from cerebrospinal fluid (CSF) can reveal novel biomarkers for diseases of the brain. Here, we validate an ultrafiltration combined with size-exclusion chromatography (UF-SEC) method for isolation of EVs from canine CSF and probe the effect of starting volume on the EV proteomics profile. First, we performed a literature review of CSF EV articles to define the current state of art, discovering a need for basic characterisation of CSF EVs. Secondly, we isolated EVs from CSF by UF-SEC and characterised the SEC fractions by protein amount, particle count, transmission electron microscopy, and immunoblotting. Data are presented as mean ± standard deviation. Using proteomics, SEC fractions 3-5 were compared and enrichment of EV markers in fraction 3 was detected, whereas fractions 4-5 contained more apolipoproteins. Lastly, we compared starting volumes of pooled CSF (6 ml, 3 ml, 1 ml, and 0.5 ml) to evaluate the effect on the proteomic profile. Even with a 0.5 ml starting volume, 743 ± 77 or 345 ± 88 proteins were identified depending on whether 'matches between runs' was active in MaxQuant. The results confirm that UF-SEC effectively isolates CSF EVs and that EV proteomic analysis can be performed from 0.5 ml of canine CSF.

Lineage specific extracellular vesicle-associated protein biomarkers for the early detection of high grade serous ovarian cancer

High grade serous ovarian carcinoma (HGSOC) accounts for ~ 70% of ovarian cancer cases. Non-invasive, highly specific blood-based tests for pre-symptomatic screening in women are crucial to reducing the mortality associated with this disease. Since most HGSOCs typically arise from the fallopian tubes (FT), our biomarker search focused on proteins found on the surface of extracellular vesicles (EVs) released by both FT and HGSOC tissue explants and representative cell lines. Using mass spectrometry, 985 EV proteins (exo-proteins) were identified that comprised the FT/HGSOC EV core proteome. Transmembrane exo-proteins were prioritized because these could serve as antigens for capture and/or detection. With a nano-engineered microfluidic platform, six newly discovered exo-proteins (ACSL4, IGSF8, ITGA2, ITGA5, ITGB3, MYOF) plus a known HGSOC associated protein, FOLR1 exhibited classification performance ranging from 85-98% in a case-control study using plasma samples representative of early (including stage IA/B) and late stage (stage III) HGSOCs. Furthermore, by linear combination of IGSF8 and ITGA5 based on logistic regression analysis, we achieved a sensitivity of 80% (99.8% specificity). These lineage-associated exo-biomarkers have potential to detect cancer while localized to the FT when patient outcomes are more favorable.

Tumour-derived extracellular vesicle based vaccines for melanoma treatment

The interest of extracellular vesicles (EVs) in cancer immunotherapy is increasing every day. EVs are lipid bilayer vesicles released by most cells, which contain the molecular signature of their parent cell. Melanoma-derived EVs present antigens specific to this aggressive type of cancer, but they also exert immunomodulatory and pro-metastatic activity. Until now, most reviews focus on the immunoevasive characteristics of tumour-derived EVs, but do not help to overcome the issues related to them. In this review, we describe isolation methods of EVs from melanoma patients and most interesting markers to oversee their effect if they are used as antigen carriers. We also discuss the methods developed so far to overcome the lack of immunogenicity of melanoma-derived EVs, which includes EV modification or adjuvant co-administration. In summary, we conclude that EVs can be an interesting antigen source for immunotherapy development once EV obtaining is optimised and the understanding of the mechanisms behind their multiple effects is further understood.

Plant-Derived Exosome-like Nanoparticles for Biomedical Applications and Regenerative Therapy

Plant-derived exosome-like nanoparticles (PDENs) comprise various bioactive biomolecules. As an alternative cell-free therapeutic approach, they have the potential to deliver nano-bioactive compounds to the human body, and thus lead to various anti-inflammatory, antioxidant, and anti-tumor benefits. Moreover, it is known that Indonesia is one of the herbal centers of the world, with an abundance of unexplored sources of PDENs. This encouraged further research in biomedical science to develop natural richness in plants as a source for human welfare. This study aims to verify the potential of PDENs for biomedical purposes, especially for regenerative therapy applications, by collecting and analyzing data from the latest relevant research and developments.

Tissue-derived extracellular vesicles: Isolation, purification, and multiple roles in normal and tumor tissues

Extracellular vesicles (EVs) are particles released from cells, and their lipid bilayer membrane encloses large amounts of bioactive molecules that endow EVs with intercellular or inter-tissue communicational abilities. Tissue-derived extracellular vesicles (Ti-EVs) are EVs directly separated from the interstitial space of tissue. They could better reflect the actual physiological or pathological state of the tissue microenvironment compared with cell line-derived EVs and biofluid EVs, indicating their potential roles in elucidating the underlying mechanism of pathogenesis and guiding the diagnosis, therapeutic targeting, and cell-free treatment of diseases. However, there have been a relatively limited number of investigations of Ti-EVs. In this review, we have summarized general procedures for Ti-EVs isolation, as well as some caveats with respect to operations after the isolation step, such as purification and storage. In addition, we have also briefly concluded the current research trends on EVs from various normal and tumor tissues, aiming to cast new light on the future research direction of Ti-EVs.

Tumor tissue derived extracellular vesicles promote diabetic wound healing

The diabetic wound nowadays remains a major public health challenge, which is characterized by overproduced reactive oxygen species (ROS). However, the current therapy for diabetic wounds is limited for reliable data in the general application. The growth of tumors has been revealed to share parallels with wound healing. Extracellular vesicles (EVs) derived from breast cancer have been reported to promote cell proliferation, migration and angiogenesis. The tumor tissue-derived EVs (tTi-EVs) of breast cancer performance a feature inheritance from original tissue and might accelerate the diabetic wound healing. We wonder whether the tumor-derived EVs are able to accelerate diabetic wound healing. In this study, tTi-EVs were extracted from breast cancer tissue via ultracentrifugation and size exclusion. Subsequently, tTi-EVs reversed the H₂O₂-induced inhibition of fibroblast proliferation and migration. Moreover, tTi-EVs significantly accelerated wound closure, collagen deposition and neovascularization, and finally promoted wound healing in diabetic mice. The tTi-EVs also reduced the level of oxidative stress in vitro and in vivo. Besides, the biosafety of tTi-EVs were preliminarily confirmed by blood tests and morphological analysis of major organs. Collectively, the present study proves that tTi-EVs can suppress oxidative stress and facilitate diabetic wound healing, which puts forward a novel function of tTi-EVs and provides potential treatment for diabetic wounds.

HRS Regulates Small Extracellular Vesicle PD-L1 Secretion and Is Associated with Anti-PD-1 Treatment Efficacy

PD-L1 localized to immunosuppressive small extracellular vesicles (sEV PD-L1) contributes to tumor progression and is associated with resistance to immune-checkpoint blockade (ICB) therapy. Here, by establishing a screening strategy with a combination of tissue microarray (TMA), IHC staining, and measurement of circulating sEV PD-L1, we found that the endosomal sorting complex required for transport (ESCRT) member protein hepatocyte growth factor-regulated tyrosine kinase substrate (HRS) was the key regulator of circulating sEV PD-L1 in head and neck squamous cell carcinoma (HNSCC) patients. Increased HRS expression was found in tumor tissues and positively correlated with elevated circulating sEV PD-L1 in patients with HNSCC. The expression of HRS was also negatively correlated to the infiltration of CD8+ T cells. Knockdown of HRS markedly reduced PD-L1 expression in HNSCC cell-derived sEVs, and these sEVs from HRS knockdown cells showed decreased immunosuppressive effects on CD8+ T cells. Knockout of HRS inhibited tumor growth in immunocompetent mice together with PD-1 blockade. Moreover, a higher HRS expression was associated with a lower response rate to anti-PD-1 therapy in patients with HNSCC. In summary, our study reveals HRS, the core component of ESCRT-0, regulates sEV PD-L1 secretion, and is associated with the response to ICB therapy in patients with HNSCC, suggesting HRS is a promising target to improve cancer immunotherapy.

microRNAs profiling of small extracellular vesicles from midbrain tissue of Parkinson's disease

Small extracellular vesicles (sEVs) are generated by all types of cells during physiological or pathological conditions. There is growing interest in tissue-derived small extracellular vesicles (tdsEVs) because they can be isolated from a single tissue source. Knowing the representation profile of microRNA (miRNA) in midbrain tissue-derived sEVs (bdsEVs) and their roles is imperative for understanding the pathological mechanism and improving the diagnosis and treatment of Parkinson's disease (PD). bdsEVs from a rat model of PD and a sham group were separated and purified using ultracentrifugation, size-exclusion chromatography (SEC), and ultrafiltration. Then, miRNA profiling of bdsEVs in both groups was performed using next-generation sequencing (NGS). The expression levels of 180 miRNAs exhibited significant differences between the two groups, including 114 upregulated and 66 downregulated genes in bdsEVs of PD rats compared with the sham group (p < 0.05). Targets of the differentially expressed miRNAs were predicted by miRanda and RNAhybrid, and their involvement in the signaling pathways and cellular function has been analyzed through the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO). Furthermore, we explored the expression levels of miR-103-3p, miR-107-3p, miR-219a-2-3p, and miR-379-5p in bdsEVs, sEVs derived from plasma, and plasma of both groups of rats. Interestingly, the expression levels of miR-103-3p, miR-107-3p, miR-219a-2-3p, and miR-379-5p were elevated in bdsEVs and sEVs from plasma; in contrast, their expression levels were decreased in plasma of the rat model of PD. In summary, miRNAs may play a significant role in the onset and development of PD, and miRNAs need to be selected carefully as a research subject for exploring the pathological mechanism and the potential therapeutic targets and diagnostic markers of PD.

Preliminary Extracellular Vesicle Profiling in Drainage Fluid After Neck Dissection in OSCC

Lymph node metastasis is related to poor prognosis in oral squamous cell carcinoma (OSCC), and few studies have explored the relevance of postoperative drainage fluid (PDF) in metastasis. Extracellular vesicles (EVs) are nanosized vesicles that can transfer oncogenic molecules to regulate tumorigenesis. However, the proteomic profile of postoperative drainage fluid-derived EVs (PDF-EVs) in OSCC has not been elucidated. Herein, we collected drainage fluid from OSCC patients after neck dissection to investigate the difference in PDF-EVs between patients with metastatic lymph nodes (the LN+ group) and nonmetastatic lymph nodes (the LN- group). The proteomic profile of PDF-EVs from the LN+ and LN- groups was compared using label-free liquid chromatography tandem-mass spectrometry-based protein quantification. The results revealed that PDF-EVs were mainly derived from epithelial cells and immune cells. A total of 2,134 proteins in the PDF-EVs were identified, and 313 were differentially expressed between the LN+ and LN- groups. Metabolic proteins, such as EHD2 and CAVIN1, were expressed at higher levels in the LN+ group than in the LN- group, and the levels of EHD2 and CAVIN1 in the postoperative drainage fluid were positively correlated with lymph node metastasis. Our study revealed previously undocumented postoperative drainage fluid-associated proteins in patients with metastatic OSCC, providing a starting point for understanding their role in metastatic and nonmetastatic OSCC.

Proteomic Profiling of the Extracellular Vesicle Chaperone in Cancer

Molecular chaperones are widely distributed intracellular proteins that play essential roles in maintaining proteome function by assisting in the folding of client proteins. Molecular chaperones, such as heat shock proteins (HSPs), are found intracellularly and extracellularly. Extracellular vesicles (EVs), such as exosomes, contain HSPs and horizontally transfer the functional chaperones into various recipient cells. Besides, mass spectrometry has enabled a comprehensive analysis of exosomal and EV proteins, which is useful in basic biomedical research to clinical biomarker search. We have performed deep proteome analysis of EVs, including exosomes, from metastatic tongue and prostate cancers and detected >700 protein types, including cytoplasmic, ER, mitochondrial, small, and large HSPs. Here, we provide protocols for isolating exosomes/EVs and deep proteome analysis to detect the EV chaperone.

Isolation and characterization of extracellular vesicles and future directions in diagnosis and therapy

Extracellular vesicles (EVs) are a unique and heterogeneous class of lipid bilayer nanoparticles secreted by most cells. EVs are regarded as important mediators of intercellular communication in both prokaryotic and eukaryotic cells due to their ability to transfer proteins, lipids and nucleic acids to recipient cells. In addition to their physiological role, EVs are recognized as modulators in pathological processes such as cancer, infectious diseases, and neurodegenerative disorders, providing new potential targets for diagnosis and therapeutic intervention. For a complete understanding of EVs as a universal cellular biological system and its translational applications, optimal techniques for their isolation and characterization are required. Here, we review recent progress in those techniques, from isolation methods to characterization techniques. With interest in therapeutic applications of EVs growing, we address fundamental points of EV-related cell biology, such as cellular uptake mechanisms and their biodistribution in tissues as well as challenges to their application as drug carriers or biomarkers for less invasive diagnosis or as immunogens. This article is categorized under: Diagnostic Tools > Biosensing Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.

Extracellular Vesicles' Role in the Pathophysiology and as Biomarkers in Cystic Fibrosis and COPD

In keeping with the extraordinary interest and advancement of extracellular vesicles (EVs) in pathogenesis and diagnosis fields, we herein present an update to the knowledge about their role in cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD). Although CF and COPD stem from a different origin, one genetic and the other acquired, they share a similar pathophysiology, being the CF transmembrane conductance regulator (CFTR) protein implied in both disorders. Various subsets of EVs, comprised mainly of microvesicles (MVs) and exosomes (EXOs), are secreted by various cell types that are either resident or attracted in the airways during the onset and progression of CF and COPD lung disease, representing a vehicle for metabolites, proteins and RNAs (especially microRNAs), that in turn lead to events as such neutrophil influx, the overwhelming of proteases (elastase, metalloproteases), oxidative stress, myofibroblast activation and collagen deposition. Eventually, all of these pathomechanisms lead to chronic inflammation, mucus overproduction, remodeling of the airways, and fibrosis, thus operating a complex interplay among cells and tissues. The detection of MVs and EXOs in blood and biological fluids coming from the airways (bronchoalveolar lavage fluid and sputum) allows the consideration of EVs and their cargoes as promising biomarkers for CF and COPD, although clinical expectations have yet to be fulfilled.

Research advances and challenges in tissue-derived extracellular vesicles

Extracellular vesicles (EV) are vesicular vesicles with phospholipid bilayer, which are present in biological fluids and extracellular microenvironment. Extracellular vesicles serve as pivotal mediators in intercellular communication by delivering lipids, proteins, and RNAs to the recipient cells. Different from extracellular vesicles derived from biofluids and that originate from cell culture, the tissue derived extracellular vesicles (Ti-EVs) send us more enriched and accurate information of tissue microenvironment. Notably, tissue derived extracellular vesicles directly participate in the crosstalk between numerous cell types within microenvironment. Current research mainly focused on the extracellular vesicles present in biological fluids and cell culture supernatant, yet the studies on tissue derived extracellular vesicles are increasing due to the tissue derived extracellular vesicles are promising agents to reflect the occurrence and development of human diseases more accurately. In this review, we aimed to clarify the characteristics of tissue derived extracellular vesicles, specify the isolation methods and the roles of tissue derived extracellular vesicles in various diseases, including tumors. Moreover, we summarized the advances and challenges of tissue derived extracellular vesicles research.

Native and engineered extracellular vesicles for wound healing

Extracellular vesicles (EVs) that act as messengers mediate communication between parent and recipient cells through their contents, including nucleic acids, proteins, and lipids. These endogenous vesicles have emerged as a novel cell-free strategy for the treatment of diseases. EVs can be released by various types of cells with unique biological properties. Recent studies have shown that native EVs are used as therapeutic agents to promote tissue repair by delivering various growth factors and trophic factors including VEGF, EGF, TFN-α, IL-1β, and TGF-β to participate in all physiological processes of wound healing. Furthermore, to improve their specificity, safety, and efficiency for wound healing, the content and surface of EVs can be designed, modified, and engineered. The engineering strategies of EVs are divided into parent cell modification and indirect modification of EVs. The therapeutic potential of current EVs and engineered EVs for wound healing still requires the exploration of their large-scale clinical applications through innovative approaches. Herein, we provide an overview of the current biological knowledge about wound healing and EVs, as well as the application of native EVs in promoting wound healing. We also outline recent advances in engineering EV methodologies to achieve ideal therapeutic potential. Finally, the therapeutic applications of engineered EVs in wound healing are reviewed, and the challenges and prospects for the translation of engineered EVs to clinical applications are discussed.

Extracellular vesicle DNA from human melanoma tissues contains cancer-specific mutations

Liquid biopsies are promising tools for early diagnosis and residual disease monitoring in patients with cancer, and circulating tumor DNA isolated from plasma has been extensively studied as it has been shown to contain tumor-specific mutations. Extracellular vesicles (EVs) present in tumor tissues carry tumor-derived molecules such as proteins and nucleic acids, and thus EVs can potentially represent a source of cancer-specific DNA. Here we identified the presence of tumor-specific DNA mutations in EVs isolated from six human melanoma metastatic tissues and compared the results with tumor tissue DNA and plasma DNA. Tumor tissue EVs were isolated using enzymatic treatment followed by ultracentrifugation and iodixanol density cushion isolation. A panel of 34 melanoma-related genes was investigated using ultra-sensitive sequencing (SiMSen-seq). We detected mutations in six genes in the EVs (BRAF, NRAS, CDKN2A, STK19, PPP6C, and RAC), and at least one mutation was detected in all melanoma EV samples. Interestingly, the mutant allele frequency was higher in DNA isolated from tumor-derived EVs compared to total DNA extracted directly from plasma DNA, supporting the potential role of tumor EVs as future biomarkers in melanoma.

Extracellular vesicles as source for the identification of minimally invasive molecular signatures in glioblastoma

The analysis of extracellular vesicles (EVs) as a source of cancer biomarkers is an emerging field since low-invasive biomarkers are highly demanded. EVs constitute a heterogeneous population of small membrane-contained vesicles that are present in most of body fluids. They are released by all cell types, including cancer cells and their cargo consists of nucleic acids, proteins and metabolites and varies depending on the biological-pathological state of the secretory cell. Therefore, EVs are considered as a potential source of reliable biomarkers for cancer. EV biomarkers in liquid biopsy can be a valuable tool to complement current medical technologies for cancer diagnosis, as their sampling is minimally invasive and can be repeated over time to monitor disease progression. In this review, we highlight the advances in EV biomarker research for cancer diagnosis, prognosis, and therapy monitoring. We especially focus on EV derived biomarkers for glioblastoma. The diagnosis and monitoring of glioblastoma still relies on imaging techniques, which are not sufficient to reflect the highly heterogenous and invasive nature of glioblastoma. Therefore, we discuss how the use of EV biomarkers could overcome the challenges faced in diagnosis and monitoring of glioblastoma.

Extracellular vesicles derived from the choroid plexus trigger the differentiation of neural stem cells

The choroid plexus secrets cerebrospinal fluid (CSF) composed of electrolytes, cytokines, growth factors, metabolites and extracellular vesicles (EVs) that flow through the interconnected brain ventricles. On their course, CSF components can act as signals that affect, for example, neural stem cells (NSCs) residing in niches of the ventricular wall. We studied EV-born CSF signals in an in vitro culture system. We purified EVs from the secretome of a choroid plexus cell line (Z310 cells), and from primary choroid plexus cultures and co-cultured those EVs with NSCs isolated from the niche of the lateral and the third ventricle. EVsZ310 and EVsCHP were purified by differential centrifugation. This yielded fractions of EVs of 50-150-nm diameter that induced a complex multicellular network formation and NSC differentiation. Both types of EV converted the round NSCs to cells that extended long processes that contacted nearby, alike-shaped cells. Mass spectrometry showed that the differentiation-inducing EVZ310 were enriched for membrane and membrane-associated proteins involved in cell differentiation, membrane trafficking, and membrane organization. We hypothesize that this type of EV Z310 cargo causes changes of stem cell morphology that leads to multicellular networks in the niches. This cell-shape transition may represent an initial step in NSC differentiation.

Extracellular vesicle isolation, purification and evaluation in cancer diagnosis

Strategies for non-invasive biomarker discovery in early detection of cancer are an urgent need. Extracellular vesicles (EVs) have generated increasing attention from the scientific community and are under intensive investigations due to their unique biological profiles and their non-invasive nature. EVs are membrane-enclosed vesicles with variable sizes and function. Such vesicles are actively secreted from multiple cell types and are considered as key vehicles for inter-cellular communications and signalling. The stability and potential to easily cross biological barriers enable EVs for exerting durable effects on target cells. These along with easy access to such vesicles, the consistent secretion from tumour during all stages of tumorigenesis and their content providing a reservoir of molecules as well as mirroring the identity of the cell of origin are virtues that have made EVs appealing to be assessed in liquid biopsy approaches and for using as a promising resource of biomarkers in cancer diagnosis and therapy and monitoring targeted cancer therapy. Early detection of EVs will guide time-scheduled personalised therapy. Surveying reliable and sensitive methods for rapid isolation of EVs from biofluids, the purity of isolated vesicles and their molecular profiling and marker specification for clinical translation in patients with cancer are issues in the area and the hot topics of many recent studies. Here, the focus is over methods for EV isolation and stratification for digging more information about liquid biopsy-based diagnosis. Extending knowledge regarding EV-based strategies is a key to validate independent patient follow-up for cancer diagnosis at early stages and inspecting the efficacy of therapeutics.

Liver Graft Proteomics Reveals Potential Incipient Mechanisms behind Early Renal Dysfunction after Liver Transplantation

Acute kidney injury (AKI) is frequent after liver transplantation (LT) and correlates with later development of chronic kidney disease. Its etiology is multifactorial and combines pre-, intra-, and postoperative factors. Additionally, the liver graft itself seems an important element in the development of AKI, yet the detailed mechanisms remain unclear. We hypothesized that grafts of LT recipients developing significant early AKI may show distinct proteomic alterations, and we set out to identify proteome differences between LT recipients developing moderate or severe AKI (n = 7) and LT recipients without early renal injury (n = 7). Liver biopsies obtained one hour after reperfusion were assessed histologically and using quantitative proteomics. Several cytokines and serum amyloid A2 (SAA2) were analyzed in serum samples obtained preoperatively, 2−4 h, and 20−24 h after graft reperfusion, respectively. LT induced mild histological alterations without significant differences between groups but uniformly altered liver function tests peaking on postoperative day 1, with a trend towards more severe alterations in patients developing AKI. Global quantitative proteomic analysis revealed 136 proteins differing significantly in their expression levels (p < 0.05, FC 20%): 80 proteins had higher and 56 had lower levels in the AKI group. Most of these proteins were related to immune and inflammatory responses, host defense, and neutrophil degranulation. No differences between the studied pro- and anti-inflammatory cytokines or SAA2 between groups were found at any moment. Our results suggest that grafts of LT patients who develop early AKI reveal a distinct proteome dominated by an early yet prominent activation of the innate immunity. These findings support the hypothesis that AKI after LT may be favored by certain graft characteristics.

The dark side of foetal bovine serum in extracellular vesicle studies

Extracellular vesicles (EVs) have been shown to be involved in cell-cell communication and to take part in both physiological and pathological processes. Thanks to their exclusive cargo, which includes proteins, lipids, and nucleic acids from the originating cells, they are gaining interest as potential biomarkers of disease. In recent years, their appealing features have been fascinating researchers from all over the world, thus increasing the number of in vitro studies focused on EV release, content, and biological activities. Cultured cell lines are the most-used source of EVs; however, the EVs released in cell cultures are influenced by the cell culture conditions, such as the use of foetal bovine serum (FBS). FBS is the most common supplement for cell culture media, but it is also a source of contaminants, such as exogenous bovine EVs, RNA, and protein aggregates, that can contaminate the cell-derived EVs and influence their cargo composition. The presence of FBS contaminants in cell-derived EV samples is a well-known issue that limits the clinical applications of EVs, thus increasing the need for standardization. In this review, we will discuss the pros and cons of using FBS in cell cultures as a source of EVs, as well as the protocols used to remove contaminants from FBS.

Apoptotic bodies for advanced drug delivery and therapy

Extracellular vesicles (EVs) have emerged as promising candidates for multiple biomedical applications. Major types of EVs include exosomes, microvesicles, and apoptotic bodies (ABs). ABs are conferred most properties from parent cells in the final stages of apoptosis. A wide variety of sources and stable morphological features are endowed to ABs by the rigorous apoptotic program. ABs accommodate more functional biomolecules by relying on the larger volume and maintaining their naturalness in circulation. The predominant body surface ratio of ABs facilitates their recognition by recipient cells and is advantageous for interactions with microenvironments. ABs can modulate and alleviate symptoms of numerous diseases for their origins, circulation, and high biocompatibility. In addition, ABs have been emerging in disease diagnosis, immunotherapy, regenerative therapy, and drug delivery. Here, we aim to present a thorough discussion on current knowledge about ABs. Of particular interest, we will summarize the application of AB-based strategies for diagnosis and disease therapy. Perspectives for the development of ABs in biomedical applications are highlighted.

Quantitative Proteomics Identifies Proteins Enriched in Large and Small Extracellular Vesicles

There is a long-held consensus that several proteins are unique to small extracellular vesicles (EVs), such as exosomes. However, recent studies have shown that several of these markers can also be present in other subpopulations of EVs to a similar degree. Furthermore, few markers have been identified as enriched or uniquely present in larger EVs, such as microvesicles. The aim of this study was to address these issues by conducting an in-depth comparison of the proteome of large and small EVs. Large (16,500g) and small EVs (118,000g) were isolated from three cell lines using a combination of differential ultracentrifugation and a density cushion and quantitative mass spectrometry (tandem mass tag-liquid chromatography-tandem mass spectrometry) was used to identify differently enriched proteins in large and small EVs. In total, 6493 proteins were quantified, with 818 and 1567 proteins significantly enriched in small and large EVs, respectively. Tetraspanins, ADAMs and ESCRT proteins, as well as SNAREs and Rab proteins associated with endosomes were enriched in small EVs compared with large EVs, whereas ribosomal, mitochondrial, and nuclear proteins, as well as proteins involved in cytokinesis, were enriched in large EVs compared with small EVs. However, Flotillin-1 was not differently expressed in large and small EVs. In conclusion, our study shows that the proteome of large and small EVs are substantially dissimilar. We validated several proteins previously suggested to be enriched in either small or large EVs (e.g., ADAM10 and Mitofilin, respectively), and we suggest several additional novel protein markers.

Isolation of mitochondria-derived mitovesicles and subpopulations of microvesicles and exosomes from brain tissues

Extracellular vesicles (EVs) are nanoscale vesicles secreted into the extracellular space by all cell types, including neurons and astrocytes in the brain. EVs play pivotal roles in physiological and pathophysiological processes such as waste removal, cell-to-cell communication and transport of either protective or pathogenic material into the extracellular space. Here we describe a detailed protocol for the reliable and consistent isolation of EVs from both murine and human brains, intended for anyone with basic laboratory experience and performed in a total time of 27 h. The method includes a mild extracellular matrix digestion of the brain tissue, a series of filtration and centrifugation steps to purify EVs and an iodixanol-based high-resolution density step gradient that fractionates different EV populations, including mitovesicles, a newly identified type of EV of mitochondrial origin. We also report detailed downstream protocols for the characterization and analysis of brain EV preparations using nanotrack analysis, electron microscopy and western blotting, as well as for measuring mitovesicular ATP kinetics. Furthermore, we compared this novel iodixanol-based high-resolution density step gradient to the previously described sucrose-based gradient. Although the yield of total EVs recovered was similar, the iodixanol-based gradient better separated distinct EV species as compared with the sucrose-based gradient, including subpopulations of microvesicles, exosomes and mitovesicles. This technique allows quantitative, highly reproducible analyses of brain EV subtypes under normal physiological processes and pathological brain conditions, including neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease.

A cryostat-based frozen section method to increase the yield of extracellular vesicles extracted from different tissues

Extracellular vesicles (EVs) are small vesicles mediating intercellular communications that have been widely used in disease diagnosis. Extracting EVs from tissues is of great importance, but current approaches are finite and the EV yield is limited. Here, the authors introduced a new method to increase EV yield based on frozen sectioning. With a standardized, semiautomated tissue-slicing procedure in a cryostat, the authors successfully isolated EVs from hearts, kidneys and stomachs. The morphology, size distribution and purity of those isolated EVs were evaluated. Additionally, compared with the traditional scalpel section method, they confirmed the higher yield of tissue-derived EVs with the cryostat-based method. The authors believe that the new method they developed would largely facilitate the research and clinical application of EVs.

Nano pom-poms prepared exosomes enable highly specific cancer biomarker detection

Extracellular vesicles (EVs), particularly nano-sized small EV exosomes, are emerging biomarker sources. However, due to heterogeneous populations secreted from diverse cell types, mapping exosome multi-omic molecular information specifically to their pathogenesis origin for cancer biomarker identification is still extraordinarily challenging. Herein, we introduced a novel 3D-structured nanographene immunomagnetic particles (NanoPoms) with unique flower pom-poms morphology and photo-click chemistry for specific marker-defined capture and release of intact exosome. This specific exosome isolation approach leads to the expanded identification of targetable cancer biomarkers with enhanced specificity and sensitivity, as demonstrated by multi-omic exosome analysis of bladder cancer patient tissue fluids using the next generation sequencing of somatic DNA mutations, miRNAs, and the global proteome (Data are available via ProteomeXchange with identifier PXD034454). The NanoPoms prepared exosomes also exhibit distinctive in vivo biodistribution patterns, highlighting the highly viable and integral quality. The developed method is simple and straightforward, which is applicable to nearly all types of biological fluids and amenable for enrichment, scale up, and high-throughput exosome isolation.

Neutral sphingomyelinase 2 inhibition attenuates extracellular vesicle release and improves neurobehavioral deficits in murine HIV

People living with HIV (PLH) have significantly higher rates of cognitive impairment (CI) and major depressive disorder (MDD) versus the general population. The enzyme neutral sphingomyelinase 2 (nSMase2) is involved in the biogenesis of ceramide and extracellular vesicles (EVs), both of which are dysregulated in PLH, CI, and MDD. Here we evaluated EcoHIV-infected mice for behavioral abnormalities relevant to depression and cognition deficits, and assessed the behavioral and biochemical effects of nSMase2 inhibition. Mice were infected with EcoHIV and daily treatment with either vehicle or the nSMase2 inhibitor (R)-(1-(3-(3,4-dimethoxyphenyl)-2,6-dimethylimidazo[1,2-b]pyridazin-8-yl)pyrrolidin-3-yl)-carbamate (PDDC) began 3 weeks post-infection. After 2 weeks of treatment, mice were subjected to behavior tests. EcoHIV-infected mice exhibited behavioral abnormalities relevant to MDD and CI that were reversed by PDDC treatment. EcoHIV infection significantly increased cortical brain nSMase2 activity, resulting in trend changes in sphingomyelin and ceramide levels that were normalized by PDDC treatment. EcoHIV-infected mice also exhibited increased levels of brain-derived EVs and altered microRNA cargo, including miR-183-5p, miR-200c-3p, miR-200b-3p, and miR-429-3p, known to be associated with MDD and CI; all were normalized by PDDC. In conclusion, inhibition of nSMase2 represents a possible new therapeutic strategy for the treatment of HIV-associated CI and MDD.

Theragnostic Applications of Mammal and Plant-Derived Extracellular Vesicles: Latest Findings, Current Technologies, and Prospects

The way cells communicate is not fully understood. However, it is well-known that extracellular vesicles (EVs) are involved. Researchers initially thought that EVs were used by cells to remove cellular waste. It is now clear that EVs function as signaling molecules released by cells to communicate with one another, carrying a cargo representing the mother cell. Furthermore, these EVs can be found in all biological fluids, making them the perfect non-invasive diagnostic tool, as their cargo causes functional changes in the cells upon receiving, unlike synthetic drug carriers. EVs last longer in circulation and instigate minor immune responses, making them the perfect drug carrier. This review sheds light on the latest development in EVs isolation, characterization and, application as therapeutic cargo, novel drug loading techniques, and diagnostic tools. We also address the advancement in plant-derived EVs, their characteristics, and applications; since plant-derived EVs only recently gained focus, we listed the latest findings. Although there is much more to learn about, EV is a wide field of research; what scientists have discovered so far is fascinating. This paper is suitable for those new to the field seeking to understand EVs and those already familiar with it but wanting to review the latest findings.