The Past, the Present, and the Future of the Size Exclusion Chromatography in Extracellular Vesicles Separation

EV71 infection alters the lipid composition of human rhabdomyosarcoma (RD) cells-derived extracellular vesicles

Previous studies demonstrated that EV71-infected cells secrete extracellular vesicles (EVs), facilitating the transfer of viral components to recipient cells and thereby promoting virus spread. Considering lipid signaling plays a crucial role in EVs-mediated cell-to-cell communication, we compared the lipid profile of EVs secreted from uninfected and EV71-infected cells (EVs-Mock and EVs-EV71) using the human rhabdomyosarcoma (RD) cell model. These two groups of EVs were purified by using size exclusion chromatography (SEC), respectively, and evaluated by transmission electron microscopy (TEM), nanoparticle tracking technology (NTA), and Western blotting (WB). In-depth lipidomic analysis of EVs identified 1705 lipid molecules belonging to 43 lipid classes. The data showed a significant increase in the lipid content of EVs after EV71 infection. Meanwhile, we deeply analyzed the changes in lipids and screened for lipid molecules with significant differences compared EVs-EV71 with EVs-Mock EVs. Altogether, we report the alterations in the lipid profile of EVs derived from RD-cells after EV71 infection, which may affect the function of the EVs in the recipient cells.

Seminal extracellular vesicles alter porcine in vitro fertilization outcome by modulating sperm metabolism

Porcine seminal plasma (SP) is loaded with a heterogeneous population of extracellular vesicles (sEVs) that modulate several reproductive-related processes. This study investigated the effect of two sEV subsets, small (S-sEVs) and large (L-sEVs), on porcine in vitro fertilization (IVF). The sEVs were isolated from nine SP pools (five ejaculates/pool) using a size-exclusion chromatography-based procedure and characterized for quantity (total protein), morphology (cryogenic electron microscopy), size distribution (dynamic light scattering), purity and EV-protein markers (flow cytometry; albumin, CD81, HSP90β). The characterization confirmed the existence of two subsets of high purity (low albumin content) sEVs that differed in size (S- and L-sEVs). In vitro fertilization was performed with in vitro matured oocytes and frozen-thawed spermatozoa and the IVF medium was supplemented during gamete coincubation (1 h at 38.5 °C, 5 % CO2 in a humidified atmosphere) with three different concentrations of each sEV subset: 0 (control, without sEVs), 0.1, and 0.2 mg/mL. The first experiment showed that sEVs, regardless of subset and concentration, decreased penetration rates and total IVF efficiency (P < 0.0001). In a subsequent experiment, it was shown that sEVs, regardless of subset and concentration, impaired the ability of spermatozoa to bind to the zona pellucida of oocytes (P < 0.0001). The following experiment showed that sEVs, regardless of the subset, bound to frozen-thawed sperm but not to in vitro matured oocytes, indicating that sEVs would affect sperm functionality but not oocyte functionality. The lack of effect on oocytes was confirmed by incubating sEVs with oocytes prior to IVF, achieving sperm-zona pellucida binding results similar to those of control. In the last experiment, conducted under IVF conditions, sperm functionality was analyzed in terms of tyrosine phosphorylation, acrosome integrity and metabolism. The sEVs, regardless of the subset, did not affect sperm tyrosine phosphorylation or acrosome integrity, but did influence sperm metabolism by decreasing sperm ATP production under capacitating conditions. In conclusion, this study demonstrated that the presence of sEVs on IVF medium impairs IVF outcomes, most likely by altering sperm metabolism.

Systematic review and bioinformatics analysis of plasma and serum extracellular vesicles proteome in type 2 diabetes

Background

Type 2 diabetes (T2D) is a complex metabolic ailment marked by a global high prevalence and significant attention in primary healthcare settings due to its elevated morbidity and mortality rates. The pathophysiological mechanisms underlying the onset and progression of this disease remain subjects of ongoing investigation. Recent evidence underscores the pivotal role of the intricate intercellular communication network, wherein cell-derived vesicles, commonly referred to as extracellular vesicles (EVs), emerge as dynamic regulators of diabetes-related complications. Given that the protein cargo carried by EVs is contingent upon the metabolic conditions of the originating cells, particular proteins may serve as informative indicators for the risk of activating or inhibiting signaling pathways crucial to the progression of T2D complications.

Methods

In this study, we conducted a systematic review to analyze the published evidence on the proteome of EVs from the plasma or serum of patients with T2D, both with and without complications (PROSPERO: CRD42023431464).

Results

Nine eligible articles were systematically identified from the databases, and the proteins featured in these articles underwent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. We identified changes in the level of 426 proteins, with CST6, CD55, HBA1, S100A8, and S100A9 reported to have high levels, while FGL1 exhibited low levels.

Conclusion

These proteins are implicated in pathophysiological mechanisms such as inflammation, complement, and platelet activation, suggesting their potential as risk markers for T2D development and progression. Further studies are required to explore this topic in greater detail.

Immunophenotype profile by flow cytometry reveals different subtypes of extracellular vesicles in porcine seminal plasma

BACKGROUND

Porcine seminal plasma (SP) is endowed with a heterogeneous population of extracellular vesicles (sEVs). This study evaluated the immunophenotypic profile by high-sensitivity flow cytometry of eight sEV subpopulations isolated according to their size (small [S-sEVs] and large [L-sEVs]) from four different SP sources, namely three ejaculate fractions (the first 10 mL of the sperm rich fraction [SRF-P1], the remaining SRF [SRF-P2], and the post-SRF [PSRF]) and entire ejaculate (EE).

METHODS

Seminal EVs were isolated using a size exclusion chromatography-based protocol from six SP pools (five ejaculates/pool) of each SP source and characterized using complementary approaches including total protein (BCA™assay), particle size distribution (dynamic light scattering), morphology (transmission electron microscopy), and purity (albumin by Western blot). Expression of CD9, CD63, CD81, CD44 and HSP90β was analyzed in all sEV subpopulations by high-sensitivity flow cytometry according to MIFlowCyt-EV guidelines, including an accurate calibration, controls, and discrimination by CFSE-labelling.

RESULTS

Each sEV subpopulation exhibited a specific immunophenotypic profile. The percentage of sEVs positive for CD9, CD63, CD81 and HSP90β differed between S- and L-sEVs (P < 0.0001). Specifically, the percentage of sEVs positive for CD9 and CD63 was higher and that for CD81 was lower in S- than L-sEVs in the four SP sources. However, the percentage of HSP90β-positive sEVs was lower in S-sEVs than L-sEVs in the SRF-P1 and EE samples. The percentage of sEVs positive for CD9, CD63, and CD44 also differed among the four SP sources (P < 0.0001), being highest in PSRF samples. Notably, virtually all sEV subpopulations expressed CD44 (range: 88.04-98.50%).

CONCLUSIONS

This study demonstrated the utility of high-sensitivity flow cytometry for sEV immunophenotyping, allowing the identification of distinct sEV subpopulations that may have different cellular origin, cargo, functions, and target cells.

The role and applications of extracellular vesicles in osteoporosis

Osteoporosis is a widely observed condition characterized by the systemic deterioration of bone mass and microarchitecture, which increases patient susceptibility to fragile fractures. The intricate mechanisms governing bone homeostasis are substantially impacted by extracellular vesicles (EVs), which play crucial roles in both pathological and physiological contexts. EVs derived from various sources exert distinct effects on osteoporosis. Specifically, EVs released by osteoblasts, endothelial cells, myocytes, and mesenchymal stem cells contribute to bone formation due to their unique cargo of proteins, miRNAs, and cytokines. Conversely, EVs secreted by osteoclasts and immune cells promote bone resorption and inhibit bone formation. Furthermore, the use of EVs as therapeutic modalities or biomaterials for diagnosing and managing osteoporosis is promising. Here, we review the current understanding of the impact of EVs on bone homeostasis, including the classification and biogenesis of EVs and the intricate regulatory mechanisms of EVs in osteoporosis. Furthermore, we present an overview of the latest research progress on diagnosing and treating osteoporosis by using EVs. Finally, we discuss the challenges and prospects of translational research on the use of EVs in osteoporosis.

mRNA vaccines in disease prevention and treatment

mRNA vaccines have emerged as highly effective strategies in the prophylaxis and treatment of diseases, thanks largely although not totally to their extraordinary performance in recent years against the worldwide plague COVID-19. The huge superiority of mRNA vaccines regarding their efficacy, safety, and large-scale manufacture encourages pharmaceutical industries and biotechnology companies to expand their application to a diverse array of diseases, despite the nonnegligible problems in design, fabrication, and mode of administration. This review delves into the technical underpinnings of mRNA vaccines, covering mRNA design, synthesis, delivery, and adjuvant technologies. Moreover, this review presents a systematic retrospective analysis in a logical and well-organized manner, shedding light on representative mRNA vaccines employed in various diseases. The scope extends across infectious diseases, cancers, immunological diseases, tissue damages, and rare diseases, showcasing the versatility and potential of mRNA vaccines in diverse therapeutic areas. Furthermore, this review engages in a prospective discussion regarding the current challenge and potential direction for the advancement and utilization of mRNA vaccines. Overall, this comprehensive review serves as a valuable resource for researchers, clinicians, and industry professionals, providing a comprehensive understanding of the technical aspects, historical context, and future prospects of mRNA vaccines in the fight against various diseases.

Advances in extracellular vesicle isolation methods: a path towards cell-type specific EV isolation

Extracellular vesicles are small, heterogenous, phospholipid-rich vesicles that are secreted by all cells into the extracellular space. They play a key role in intercellular communication because they can transport a variety of biomolecules such as proteins, lipids, and nucleic acids between cells. As categorized by the International Society of Extracellular Vesicles (ISEV), the term EV encompasses different sub-types, including exosomes, microvesicles, and apoptotic bodies, which differ in their size, origin, and cargo. EVs can be isolated from biological fluids such as blood, urine, and cerebrospinal fluid, and their biomolecular content can be analyzed to monitor the progression of certain diseases. Therefore, EVs can be used as a new source of liquid biomarkers for advancing novel diagnostic and therapeutic tools. Isolating and analyzing EVs can be challenging due to their nanoscopic size and low abundance. Several techniques have been developed for the isolation and characterization of EVs, including ultracentrifugation, density gradient separation, size-exclusion chromatography, microfluidics, and magnetic bead-based/affinity methods. This review highlights advances in EV isolation techniques in the last decade and provides a perspective on their advantages, limitations, and potential application to cell-type specific EV isolation in the future.

Optimization of extracellular vesicle isolation and their separation from lipoproteins by size exclusion chromatography

Interest in the use of extracellular vesicles (EVs) as biomarkers of disease is rapidly growing. However, one main unsolved issue in the EV field is finding a technique able to eliminate non-EV contaminants present in biofluid samples in a one-step isolation protocol. Due to the expansion and value of size exclusion chromatography (SEC) as one of the best EV isolation methods, we have tested several agarose resins with different agarose percentages, bead sizes and crosslinking features to optimize EV isolation. For this optimization of SEC, we first employed conditioned media from a melanoma cell culture, a simpler sample in comparison to biological fluids, but which also contains abundant contaminants such as soluble protein and lipoproteins (LPPs). The distinct agaroses and the combinations of resins with different agarose percentages in the same column were tested. Soluble protein, EVs and LPPs levels from the different eluted fractions were quantitated by immunodetection or absorbance measurements. Samples were also analysed by NTA and TEM to verify the yield and the LPP contamination. Different percentages of agarose resins (2%, 4% and 6%) yielded samples with increasing LPP contamination respectively, which was not improved in the columns that combined them. Crosslinking of the agarose did not affect EV isolation yield nor the LPP contamination. In contrast, reducing the bead size greatly improved EV purity. We thus selected 4% Rapid Run Fine agarose beads as the resin that more efficiently isolated EVs with almost no contamination of other particles. Using blood plasma samples, this resin also demonstrated an improved capacity in the isolation of EVs from LPPs in comparison to the agaroses most commonly used in the field and differential ultracentrifugation.

Engineered extracellular vesicles (EVs): Promising diagnostic/therapeutic tools for pediatric high-grade glioma

Diffuse intrinsic pontine glioma (DIPG) is a highly malignant brain tumor that mainly occurs in children with extremely low overall survival. Traditional therapeutic strategies, such as surgical resection and chemotherapy, are not feasible mostly due to the special location and highly diffused features. Radiotherapy turns out to be the standard treatment method but with limited benefits of overall survival. A broad search for novel and targeted therapies is in the progress of both preclinical investigations and clinical trials. Extracellular vesicles (EVs) emerged as a promising diagnostic and therapeutic candidate due to their distinct biocompatibility, excellent cargo-loading-delivery capacity, high biological barrier penetration efficiency, and ease of modification. The utilization of EVs in various diseases as biomarker diagnoses or therapeutic agents is revolutionizing modern medical research and practice. In this review, we will briefly talk about the research development of DIPG, and present a detailed description of EVs in medical applications, with a discussion on the application of engineered peptides on EVs. The possibility of applying EVs as a diagnostic tool and drug delivery system in DIPG is also discussed.

Engineered mesenchymal stem cell-derived extracellular vesicles: A state-of-the-art multifunctional weapon against Alzheimer's disease

With the increase of population aging, the number of Alzheimer's disease (AD) patients is also increasing. According to current estimates, approximately 11% of people over 65 suffer from AD, and that percentage rises to 42% among people over 85. However, no effective treatment capable of decelerating or stopping AD progression is available. Furthermore, AD-targeted drugs composed of synthetic molecules pose concerns regarding biodegradation, clearance, immune response, and neurotoxicity. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) are essential intercellular communication mediators holding great promise as AD therapeutics owing to their biocompatibility, versatility, effortless storage, superior safety, and the ability to transport messenger and noncoding RNAs, proteins, lipids, DNAs, and other bioactive compounds derived from cells. The functionalisation and engineering strategies of MSC-EVs are highlighted (e.g. preconditioning, drug loading, surface modification, and artificial EV fabrication), which could improve AD treatment by multiple therapeutic effects, including clearing abnormal protein accumulation and achieving neuroprotection and immunomodulatory effects. Herein, this review summarises state-of-the-art strategies to engineer MSC-EVs, discusses progress in their use as AD therapeutics, presents the perspectives and challenges associated with the related clinical applications, and concludes that engineered MSC-EVs show immense potential in AD therapy.

Comparison of proteomic landscape of extracellular vesicles in pleural effusions isolated by three strategies

Extracellular vesicles (EVs) derived from pleural effusion (PE) is emerging as disease biomarkers. However, the methods for isolation of EVs from PE (pEVs) were rarely studied. In our study, three methods for isolating pEVs of lung cancer patients were compared, including ultracentrifugation (UC), a combination of UC and size exclusion chromatography (UC-SEC) and a combination of UC and density gradient ultracentrifugation (UC-DGU). The subpopulation of pEVs was identified by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), Western blotting (WB) and nano-flow cytometry (nFCM). Additionally, the proteomic landscape of pEVs was analyzed by Label-free proteomics. The results showed that, compared with UC and UC-DGU, the UC-SEC method separated pEVs with the highest purity. In the proteomic analysis, on average, 1595 proteins were identified in the pEVs isolated by UC-SEC, much more than pEVs isolated by UC (1222) or UC-DGU (807). Furthermore, approximately 90% of identified proteins in each method were found in the EVs public database ExoCarta. Consistent with this, GO annotation indicated that the core proteins identified in each method were mainly enriched in "extracellular exosome." Many of the top 100 proteins with high expression in each method were suggested as protein markers to validate the presence of EVs in the MISEV2018 guidelines. In addition, combined with lung tissue-specific proteins and vesicular membrane proteins, we screened out and validated several novel protein markers (CD11C, HLA DPA1 and HLA DRB1), which were enriched in pEVs rather than in plasma EVs. In conclusion, our study shows that the method of UC-SEC could significantly improve the purity of EVs and the performance of mass spectrometry-based proteomic profiling in analyzing pEVs. The exosomal proteins CD11C, HLA DPA1 and HLA DRB1 may act as potential markers of pEVs. The proteomic analysis of pEVs provides important information and new ideas for studying diseases complicated with PE.

Advances in Purification, Modification, and Application of Extracellular Vesicles for Novel Clinical Treatments

Extracellular vesicles (EV) are membrane vesicles surrounded by a lipid bilayer membrane and include microvesicles, apoptotic bodies, exosomes, and exomeres. Exosome-encapsulated microRNAs (miRNAs) released from cancer cells are involved in the proliferation and metastasis of tumor cells via angiogenesis. On the other hand, mesenchymal stem cell (MSC) therapy, which is being employed in regenerative medicine owing to the ability of MSCs to differentiate into various cells, is due to humoral factors, including messenger RNA (mRNA), miRNAs, proteins, and lipids, which are encapsulated in exosomes derived from transplanted cells. New treatments that advocate cell-free therapy using MSC-derived exosomes will significantly improve clinical practice. Therefore, using highly purified exosomes that perform their original functions is desirable. In this review, we summarized advances in the purification, modification, and application of EVs as novel strategies to treat some diseases.

Seminal extracellular vesicles subsets modulate gene expression in cumulus cells of porcine in vitro matured oocytes

Seminal plasma (SP), a fluid composed mainly by secretions from accessory sex glands, contains a heterogenous population of extracellular vesicles (EVs), involved in several reproductive physiological processes. Seminal plasma has been found to modulate ovary function, in terms of hormone secretion and immune regulation. This study evaluated the potential effect of SP-EV-subsets on the modulation of cumulus-oocyte-complex (COCs) physiology during in vitro maturation (IVM). Two SP-EV-subsets, small-EVs (S-EVs) and large-EVs (L-EVs), were isolated from pig SP by size-exclusion-chromatography. Next, COCs were IVM in the absence (control) or presence of each SP-EV-subset to evaluate their uptake by COCs (PKH67-EVs labelling) and their effect on oocyte and cumulus cells (CCs) (gene expression, and progesterone and estradiol-17β levels). S-EVs and L-EVs were able to bind CCs but not oocytes. Supplementation with L-EVs induced changes (P ≤ 0.05) in the transcript levels of oocyte maturation- (HAS2) and steroidogenesis-related genes (CYP11A1 and HSD3B1) in CCs. No effect on nuclear oocyte maturation and progesterone and estradiol-17β levels was observed when COCs were IVM with any of the two SP-EV-subsets. In conclusion, while SP-EV-subsets can be integrated by CCs during IVM, they do not affect oocyte maturation and only L-EVs are able to modulate CCs function, mainly modifying the expression of steroidogenesis-related genes.

Choroid plexus-derived extracellular vesicles exhibit brain targeting characteristics

The brain is protected against invading organisms and other unwanted substances by tightly regulated barriers. However, these central nervous system (CNS) barriers impede the delivery of drugs into the brain via the blood circulation and are therefore considered major hurdles in the treatment of neurological disorders. Consequently, there is a high need for efficient delivery systems that are able to cross these strict barriers. While most research focuses on the blood-brain barrier (BBB), the design of drug delivery platforms that are able to cross the blood-cerebrospinal fluid (CSF) barrier, formed by a single layer of choroid plexus epithelial cells, remains a largely unexplored domain. The discovery that extracellular vesicles (EVs) make up a natural mechanism for information transfer between cells and across cell layers, has stimulated interest in their potential use as drug delivery platform. Here, we report that choroid plexus epithelial cell-derived EVs exhibit the capacity to home to the brain after peripheral administration. Moreover, these vesicles are able to functionally deliver cargo into the brain. Our findings underline the therapeutic potential of choroid plexus-derived EVs as a brain drug delivery vehicle via targeting of the blood-CSF interface.

Extracellular Vesicles in Tissue Engineering: Biology and Engineered Strategy

Extracellular vesicles (EVs), acting as an important ingredient of intercellular communication through paracrine actions, have gained tremendous attention in the field of tissue engineering (TE). Moreover, these nanosized extracellular particles (30-140 nm) can be incorporated into biomaterials according to different principles to facilitate signal delivery in various regenerative processes directly or indirectly. Bioactive biomaterials as the carrier will extend the retention time and realize the controlled release of EVs, which further enhance their therapeutic efficiency in tissue regeneration. Herein, the basic biological characteristics of EVs are first introduced, and then their outstanding performance in exerting direct impacts on target cells in tissue regeneration as well as indirect effects on promoting angiogenesis and regulating the immune environment, due to specific functional components of EVs (nucleic acid, protein, lipid, etc.), is emphasized. Furthermore, different design ideas for suitable EV-loaded biomaterials are also demonstrated. In the end, this review also highlights the engineered strategies, which aim at solving the problems related to natural EVs such as highly heterogeneous functions, inadequate tissue targeting capabilities, insufficient yield and scalability, etc., thus promoting the therapeutic pertinence and clinical potential of EV-based approaches in TE.

The Emerging Role of Extracellular Vesicle Derived From Neurons/Neurogliocytes in Central Nervous System Diseases: Novel Insights Into Ischemic Stroke

Neurons and neurogliocytes (oligodendrocytes, astrocytes, and microglia) are essential for maintaining homeostasis of the microenvironment in the central nervous system (CNS). These cells have been shown to support cell-cell communication via multiple mechanisms, most recently by the release of extracellular vesicles (EVs). Since EVs carry a variety of cargoes of nucleic acids, lipids, and proteins and mediate intercellular communication, they have been the hotspot of diagnosis and treatment. The mechanisms underlying CNS disorders include angiogenesis, autophagy, apoptosis, cell death, and inflammation, and cell-EVs have been revealed to be involved in these pathological processes. Ischemic stroke is one of the most common causes of death and disability worldwide. It results in serious neurological and physical dysfunction and even leads to heavy economic and social burdens. Although a large number of researchers have reported that EVs derived from these cells play a vital role in regulating multiple pathological mechanisms in ischemic stroke, the specific interactional relationships and mechanisms between specific cell-EVs and stroke treatment have not been clearly described. This review aims to summarize the therapeutic effects and mechanisms of action of specific cell-EVs on ischemia. Additionally, this study emphasizes that these EVs are involved in stroke treatment by inhibiting and activating various signaling pathways such as ncRNAs, TGF-β1, and NF-κB.

Isolation methods of large and small extracellular vesicles derived from cardiovascular progenitors: A comparative study

Since the discovery of the beneficial therapeutical effects of extracellular vesicles (EVs), these agents have been attracting great interest as next-generation therapies. EVs are nanosized membrane bodies secreted by all types of cells that mediate cell-cell communication. Although the classification of different subpopulations of EVs can be complex, they are broadly divided into microvesicles and exosomes based on their biogenesis and in large and small EVs based on their size. As this is an emerging field, current investigations are focused on basic aspects such as the more convenient method for EV isolation. In the present paper, we used cardiac progenitor cells (CPCs) to study and compare different cell culture conditions for EV isolation as well as two of the most commonly employed purification methods: ultracentrifugation (UC) and size-exclusion chromatography (SEC). Large and small EVs were separately analysed. We found that serum starvation of cells during the EV collecting period led to a dramatic decrease in EV secretion and major cell death. Regarding the isolation method, our findings suggest that UC and SEC gave similar EV recovery rates. Separation of large and small EV-enriched subpopulations was efficiently achieved with both purification protocols although certain difference in sample heterogeneity was observed. Noteworthy, while calnexin was abundant in large EVs, ALIX and CD63 were mainly found in small EVs. Finally, when the functionality of EVs was assessed on primary culture of adult murine cardiac fibroblasts, we found that EVs were taken up by these cells, which resulted in a pronounced reduction in the proliferative and migratory capacity of the cells. Specifically, a tendency towards a larger effect of SEC-related EVs was observed. No differences could be found between large and small EVs. Altogether, these results contribute to establish the basis for the use of EVs as therapeutic platforms, in particular in regenerative fields.