International Society For Extracellular Vesicles Research Articles

Comparison of EV-free fraction, EVs, and total secretome of amniotic mesenchymal stromal cells for their immunomodulatory potential: a translational perspective.

Amniotic mesenchymal stromal cells (hAMSCs) have unique immunomodulatory properties demonstrated in vitro and in vivo in various diseases in which the dysregulated immune system plays a major role. The immunomodulatory and pro-regenerative effects of MSCs, among which hAMSCs lie in the bioactive factors they secrete and in their paracrine activity, is well known. The mix of these factors (i.e., secretome) can be either freely secreted or conveyed by extracellular vesicles (EV), thus identifying two components in the cell secretome: EV-free and EV fractions. This study aimed to discern the relative impact of the individual components on the immunomodulatory action of the hAMSC secretome in order to obtain useful information for implementing future therapeutic approaches using immunomodulatory therapies based on the MSC secretome. To this aim, we isolated EVs from the hAMSC secretome (hAMSC-CM) by ultracentrifugation and validated the vesicular product according to the International Society for Extracellular Vesicles (ISEV) criteria. EVs were re-diluted in serum-free medium to maintain the EV concentration initially present in the original CM. We compared the effects of the EV-free and EV fractions with those exerted by hAMSC-CM in toto on the activation and differentiation of immune cell subpopulations belonging to both the innate and adaptive immune systems.We observed that the EV-free fraction, similar to hAMSC-CM in toto, a) decreases the proliferation of activated peripheral blood mononuclear cells (PBMC), b) reduces the polarization of T cells toward inflammatory Th subsets, and induces the induction of regulatory T cells; c) affects monocyte polarization to antigen-presenting cells fostering the acquisition of anti-inflammatory macrophage (M2) markers; and d) reduces the activation of B lymphocytes and their maturation to plasma cells. We observed instead that all investigated EV fractions, when used in the original concentrations, failed to exert any immunomodulatory effect, even though we show that EVs are internalized by various immune cells within PBMC. These findings suggest that the active component able to induce immune regulation, tested at original concentrations, of the hAMSC secretome resides in factors not conveyed in EVs. However, EVs isolated from hAMSC could exert actions on other cell types, as reported by others.

Abstract 5106: Distinct molecular profiles of serum-derived extracellular vesicles in high-grade serous ovarian cancer

Abstract Background: Patients with high-grade serous ovarian cancer (HGSC) who have no visible residual disease (CGR) after primary surgery have the best clinical outcomes, followed by patients who undergo neoadjuvant chemotherapy (NACT) and have response enabling interval cytoreductive surgery. Through comprehensive omics analyses, we previously characterized molecular and cellular profiles of highly clinically defined HGSC from patients who had CGR versus those triaged to NACT. However, clinically useful predictive biomarkers for such distinctions are still lacking. Extracellular vesicles (EVs) have been recognized as liquid biopsy-based biomarkers for early cancer detection and disease surveillance in other disease settings. Here, we performed extensive molecular characterization of serum-derived EVs and correlated them with therapeutic outcomes in patients with HGSC. Methods: Serum-derived medium/large size EVs from patients with HGSC treated under a systematic surgical algorithm were isolated following standard methods of the International Society for Extracellular Vesicles. Patients had either complete gross resection after primary surgery (R0, n=3); poor response to NACT (NACT-PR, n=4), or excellent response to NACT with carboplatin and paclitaxel (NACT-ER, n=3); tissue and matched germline blood samples have already been comprehensively analyzed (Lee et al, Cell Reports, 2020). The isolated EV-DNA and EV-RNA were subjected to whole-genome sequencing and RNA sequencing, respectively. Results: We identified somatic EV-DNA alterations in cancer hallmark genes, including FAT1 and KMT2D as the most frequent mutated genes. Interestingly, we found alterations in ovarian cancer-related genes, including BRCA2 and RAD51 in R0; BRCA2 in NACT-ER; TP53, CDK13, CDK12, BRAF, AKT2, and ARID1A in NACT-PR patients. We also identified 26,338 genes expressed in the EV-RNA transcriptomic profiles. The analysis of the enrichment of cancer hallmark pathways showed that the R0 group was more enriched in the interferon α/γ, PI3K/AKT/mTOR signaling, and DNA repair pathways. Interestingly, we also identified 6,757 differentially expressed genes (DEGs) in the CGR versus the NACT groups (absolute log2-fold change ≥2 and adjusted p-value <0.05). Among the DEGs, we identified 67 genes that were cancer hallmark genes, and 21 of them were overexpressed in the NACT group and 46 were overexpressed in the R0 group. Noticeably, 11 DEGs were directly related to ovarian cancer: TP53, PTEN, CCND1, BARD1, PMS2, and MLH3 were significantly overexpressed in the NACT group, while BRCA2, CSMD3, and GABRA6 were overexpressed in the R0 group. Conclusions: Taken together, our preliminary data suggest that molecular characteristics of EVs could provide an accurate prediction of patients with HGSC who can undergo CGR with surgery and respond to chemotherapy. Citation Format: Li Zhao, Shaolin Ma, Nicole D. Fleming, Joseph Celestino, Mark S. Kim, Richard A. Hajek, Nicholas B. Jennings, Erika J. Thompson, Hongli Tang, Shannon N. Westin, Amir A. Jazaeri, Jianhua Zhang, P Andrew Futreal, Anil K. Sood, Sanghoon Lee. Distinct molecular profiles of serum-derived extracellular vesicles in high-grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5106.

Characterisation of Extracellular Vesicles from Equine Mesenchymal Stem Cells.

Extracellular vesicles (EVs) are nanosized lipid bilayer-encapsulated particles secreted by virtually all cell types. EVs play an essential role in cellular crosstalk in health and disease. The cellular origin of EVs determines their composition and potential therapeutic effect. Mesenchymal stem/stromal cell (MSC)-derived EVs have shown a comparable therapeutic potential to their donor cells, making them a promising tool for regenerative medicine. The therapeutic application of EVs circumvents some safety concerns associated with the transplantation of viable, replicating cells and facilitates the quality-controlled production as a ready-to-go, off-the-shelf biological therapy. Recently, the International Society for Extracellular Vesicles (ISEV) suggested a set of minimal biochemical, biophysical and functional standards to define extracellular vesicles and their functions to improve standardisation in EV research. However, nonstandardised EV isolation methods and the limited availability of cross-reacting markers for most animal species restrict the application of these standards in the veterinary field and, therefore, the species comparability and standardisation of animal experiments. In this study, EVs were isolated from equine bone-marrow-derived MSCs using two different isolation methods, stepwise ultracentrifugation and size exclusion chromatography, and minimal experimental requirements for equine EVs were established and validated. Equine EVs were characterised using a nanotracking analysis, fluorescence-triggered flow cytometry, Western blot and transelectron microscopy. Based on the ISEV standards, minimal criteria for defining equine EVs are suggested as a baseline to allow the comparison of EV preparations obtained by different laboratories.

Preclinical Studies on Convalescent Human Immune Plasma-Derived Exosome: Omics and Antiviral Properties to SARS-CoV-2.

The scale of the COVID-19 pandemic forced urgent measures for the development of new therapeutics. One of these strategies is the use of convalescent plasma (CP) as a conventional source for passive immunity. Recently, there has been interest in CP-derived exosomes. In this report, we present a structural, biochemical, and biological characterization of our proprietary product, convalescent human immune plasma-derived exosome (ChipEXO), following the guidelines set forth by the Turkish Ministry of Health and the Turkish Red Crescent, the Good Manufacturing Practice, the International Society for Extracellular Vesicles, and the Gene Ontology Consortium. The data support the safety and efficacy of this product against SARS-CoV-2 infections in preclinical models.

Advances in the Field of Micro- and Nanotechnologies Applied to Extracellular Vesicle Research: Take-Home Message from ISEV2021.

Extracellular Vesicles (EVs) are naturally secreted nanoparticles with a plethora of functions in the human body and remarkable potential as diagnostic and therapeutic tools. Starting from their discovery, EV nanoscale dimensions have hampered and slowed new discoveries in the field, sometimes generating confusion and controversies among experts. Microtechnological and especially nanotechnological advances have sped up biomedical research dealing with EVs, but efforts are needed to further clarify doubts and knowledge gaps. In the present review, we summarize some of the most interesting data presented in the Annual Meeting of the International Society for Extracellular Vesicles (ISEV), ISEV2021, to stimulate discussion and to share knowledge with experts from all fields of research. Indeed, EV research requires a multidisciplinary knowledge exchange and effort. EVs have demonstrated their importance and significant biological role; still, further technological achievements are crucial to avoid artifacts and misleading conclusions in order to enable outstanding discoveries.

Adherence to minimal experimental requirements for defining extracellular vesicles and their functions.

Rigorous measures are required to cope with the advance of extracellular vesicle (EV) research, from 183 studies published in 2012 to 2,309 studies published in 2020. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (MISEV) guidelines in 2014, updated in 2018, for assuring and improving EV research quality. We performed a systematic review using a text mining approach to assess adherence to MISEV criteria. A keyword search was conducted in 5,093 accessible publications over the period 2012-2020 and analyzed the methodology used for EV isolation and characterization. We found a significant improvement over the years particularly regarding EV characterization where recent papers used a higher number of methods and EV markers to check for quantity and purity. Interestingly, we also found that EV papers using more methods and EV markers were cited more frequently. Papers citing MISEV criteria were more prone to use a higher number of characterization methods. We therefore established a concise checklist summarizing MISEV criteria to support EV researchers towards reaching the highest standards in the field.

Platelet-Derived Extracellular Vesicles for Regenerative Medicine.

Extracellular vesicles (EVs) present a great potential for the development of new treatments in the biomedical field. To be used as therapeutics, many different sources have been used for EVs obtention, while only a few studies have addressed the use of platelet-derived EVs (pEVs). In fact, pEVs have been shown to intervene in different healing responses, thus some studies have evaluated their regenerative capability in wound healing or hemorrhagic shock. Even more, pEVs have proven to induce cellular differentiation, enhancing musculoskeletal or neural regeneration. However, the obtention and characterization of pEVs is widely heterogeneous and differs from the recommendations of the International Society for Extracellular Vesicles. Therefore, in this review, we aim to present the main advances in the therapeutical use of pEVs in the regenerative medicine field while highlighting the isolation and characterization steps followed. The main goal of this review is to portray the studies performed in order to enhance the translation of the pEVs research into feasible therapeutical applications.

CAD increases the long noncoding RNA PUNISHER in small extracellular vesicles and regulates endothelial cell function via vesicular shuttling

Long noncoding RNAs (lncRNAs) have emerged as biomarkers and regulators of cardiovascular disease. However, the expression pattern of circulating extracellular vesicle (EV)-incorporated lncRNAs in patients with coronary artery disease (CAD) is still poorly investigated. A human lncRNA array revealed that certain EV-lncRNAs are significantly dysregulated in CAD patients. Circulating small EVs (sEVs) from patients with (n = 30) or without (n = 30) CAD were used to quantify PUNISHER (also known as AGAP2-antisense RNA 1 [AS1]), GAS5, MALAT1, and H19 RNA levels. PUNISHER (p = 0.002) and GAS5 (p = 0.02) were significantly increased in patients with CAD, compared to non-CAD patients. Fluorescent labeling and quantitative real-time PCR of sEVs demonstrated that functional PUNISHER was transported into the recipient cells. Mechanistically, the RNA-binding protein, heterogeneous nuclear ribonucleoprotein K (hnRNPK), interacts with PUNISHER, regulating its loading into sEVs. Knockdown of PUNISHER abrogated the EV-mediated effects on endothelial cell (EC) migration, proliferation, tube formation, and sprouting. Angiogenesis-related gene profiling showed that the expression of vascular endothelial growth factor A (VEGFA) RNA was significantly increased in EV recipient cells. Protein stability and RNA immunoprecipitation indicated that the PUNISHER-hnRNPK axis regulates the stability and binding of VEGFA mRNA to hnRNPK. Loss of PUNISHER in EVs abolished the EV-mediated promotion of VEGFA gene and protein expression. Intercellular transfer of EV-incorporated PUNISHER promotes a pro-angiogenic phenotype via a VEGFA-dependent mechanism.

Mesenchymal Stem Cell-Derived Exosomes: A Potential Therapeutic Avenue in Knee Osteoarthritis.

Knee osteoarthritis is the leading cause of functional disability in adults. The goals of knee osteoarthritis management are directed toward symptomatic pain relief along with the attainment of the functional quality of life. The treatment strategy ranges from conservative to surgical management with reparative and restorative techniques. The emergence of cell-based therapies has paved the way for the usage of mesenchymal stem cells (MSCs) in cartilage disorders. Currently, global researchers are keen on their research on nanomedicine and targeted drug delivery. MSC-derived exosomes act as a directed therapy to halt the disease progression and to provide a pain-free range of movements with increased quality of cartilage on regeneration. International Society for Extracellular Vesicles and the European Network on Microvesicles and Exosomes in Health and Disease have formed guidelines to foster the use of the growing therapeutic potential of exosomal therapy in osteoarthritis. Although regenerative therapies with MSC are being seen to hold a future in the management of osteoarthritis, extracellular vesicle-based technology holds the key to unlock the potential toward knee preservation and regeneration. The intricate composition and uncertain functioning of exosomes are inquisitive facets warranting further exploration.

Methods for Separation and Characterization of Extracellular Vesicles: Results of a Worldwide Survey Performed by the ISEV Rigor and Standardization Subcommittee.

Research on extracellular vesicles (EVs) is growing exponentially due to an increasing appreciation of EVs as disease biomarkers and therapeutics, an expanding number of EV-containing materials under study, and application of new preparation, detection, and cargo analysis methods. Diversity of both sources and methodologies imposes challenges on the comparison of measurement results between studies and laboratories. While reference guidelines and minimal requirements for EV research have achieved the important objective of assembling community consensus, it is also essential to understand which methodologies and quality controls are currently being applied, and how usage trends are evolving. As an initial response to this need, the International Society for Extracellular Vesicles (ISEV) performed a worldwide survey in 2015 on “Techniques used for the isolation and characterization of extracellular vesicles” and published the results from this survey in 2016. In 2019, a new survey was performed to assess the changing state of the field. The questionnaire received more than 600 full or partial responses, and the present manuscript summarizes the results of this second worldwide survey. The results emphasize that separation methods such as ultracentrifugation and density gradients are still the most commonly used methods, the use of size exclusion chromatography has increased, and techniques based on tangential flow and microfluidics are now being used by more than 10% of respondents. The survey also reveals that most EV researchers still do not perform sample quality controls before or after isolation of EVs. Finally, the majority of EV researchers emphasize that separation and characterization of EVs should receive more attention.

International Society for Extracellular Vesicles and International Society for Cell and Gene Therapy statement on extracellular vesicles from mesenchymal stromal cells and other cells: considerations for potential therapeutic agents to suppress coronavirus disease-19

STATEMENT: The International Society for Cellular and Gene Therapies (ISCT) and the International Society for Extracellular Vesicles (ISEV) recognize the potential of extracellular vesicles (EVs, including exosomes) from mesenchymal stromal cells (MSCs) and possibly other cell sources as treatments for COVID-19. Research and trials in this area are encouraged. However, ISEV and ISCT do not currently endorse the use of EVs or exosomes for any purpose in COVID-19, including but not limited to reducing cytokine storm, exerting regenerative effects or delivering drugs, pending the generation of appropriate manufacturing and quality control provisions, pre-clinical safety and efficacy data, rational clinical trial design and proper regulatory oversight.

Macrolets: Outsized Extracellular Vesicles Released from Lipopolysaccharide-Stimulated Macrophages that Trap and Kill Escherichia coli.

SummaryMacrophages release a variety of extracellular vesicles (EVs). Here we describe a previously unreported class of EVs that are released from macrophages in response to Escherichia coli endotoxin, lipopolysaccharide (LPS), that we have named "macrolets" since they are extruded as large "droplets" released from macrophages. Morphologically, macrolets are anuclear, bounded by a single lipid membrane and structurally dependent on an actin cytoskeleton. Macrolets are enriched in tetraspanins and separable on this basis from their parent macrophages. Macrolets are distinguished from classic exosomes by their larger size (10–30 μm), discoid shape, and the presence of organelles. Macrolets are rich in both interleukin 6 (IL-6) and interleukin 6 receptor (IL-6R),and are capable of trapping and killing E. coli in association with production of reactive oxygen species. Our observations offer insights into the mechanisms by which macrophage activities may be amplified in sites of infection, inflammation, and healing.

Biological membranes in EV biogenesis, stability, uptake, and cargo transfer: an ISEV position paper arising from the ISEV membranes and EVs workshop

ABSTRACTParacrine and endocrine roles have increasingly been ascribed to extracellular vesicles (EVs) generated by multicellular organisms. Central to the biogenesis, content, and function of EVs are their delimiting lipid bilayer membranes. To evaluate research progress on membranes and EVs, the International Society for Extracellular Vesicles (ISEV) conducted a workshop in March 2018 in Baltimore, Maryland, USA, bringing together key opinion leaders and hands-on researchers who were selected on the basis of submitted applications. The workshop was accompanied by two scientific surveys and covered four broad topics: EV biogenesis and release; EV uptake and fusion; technologies and strategies used to study EV membranes; and EV transfer and functional assays. In this ISEV position paper, we synthesize the results of the workshop and the related surveys to outline important outstanding questions about EV membranes and describe areas of consensus. The workshop discussions and survey responses reveal that while much progress has been made in the field, there are still several concepts that divide opinion. Good consensus exists in some areas, including particular aspects of EV biogenesis, uptake and downstream signalling. Areas with little to no consensus include EV storage and stability, as well as whether and how EVs fuse with target cells. Further research is needed in these key areas, as a better understanding of membrane biology will contribute substantially towards advancing the field of extracellular vesicles.

Sonication and Short-term Incubation Alter the Content of Bovine Milk Exosome Cargos and Exosome Bioavailability (OR26-08-19)

ObjectivesExosomes are endogenous nanoparticles that participate in cell-to-cell communication through the transfer of cargos such RNAs, lipids and proteins from donor cells to recipient cells. Previously, we showed that mammals absorb exosomes from milk. Ultrasonication causes a transient disruption of the exosome membranes, leading to loss of microRNAs. When mice were fed diets based on the AIN-93G formulation, modified to contain a physiological amount of milk exosomes (exosome and RNA-sufficient diet, ERS) or sonicated exosomes (exosome and RNA-depleted diet, ERD), we observed a loss of circulating and tissue microRNAs and phenotypes such as aberrant purine metabolism. The objective of this study was to conduct a comprehensive analysis ofthe effects of sonication on exosomes cargos and bioavailability, thereby generating insights into mechanisms through which ERD elicits phenotypes. MethodsExosomes were isolated from ultrasonicated (USE) and non-sonicated (NSE) bovine milk by ultracentrifugation and authenticated following guidelines of the International Society for Extracellular Vesicles. MicroRNAs were analyzed by small RNA-sequencing. Lipids and proteins were analyzed by LC/MS-MS. Intestinal transport was assessed using FM 4-64-labeled exosomes in primary human small intestine cells (FHs cells). Bioavailability of exosomes transfected with IRDye-labeled miR-320a was assessed using oral gavage in C57BL/6 mice.The unpaired t-test was used for statistical analysis P < 0.05 was considered statistically significant. ResultsUltrasonication affected the vesicle count and exosome morphology. Western blot analysis detected marker proteins only in NSE. The content of microRNAs was about 93% lower in USE than NSE. Significant difference was noted for lipid and protein identities between NSE and USE. Reduced uptake of USE by intestinal cells and loss of cargo accumulation in murine livers and pancreas for USE compared to NSE (Fig. 1-5). ConclusionsUltrasonication causesa loss of microRNAs in milk exosomes. The unique patterns of proteins and lipids likely is due to an exchangeof membranes between exosomes and other vesicles during ultrasonication, which might explain the lower bioavailability of USE compared to NSE. We currently test the exchange of lipids during ultrasonication. Funding SourcesNIFA, NIH, Gates Foundation, PureTech, Inc. and USDA Hatch and Multistate. J.Z. is a consultant for PureTech. Supporting Tables, Images and/or Graphs▪▪▪▪▪

Exosomes derived from mesenchymal Stem cells alleviate atopic dermatitis by suppressing inflammation and improving skin barrier function

Background & Aim Introduction Atopic dermatitis (AD) is a chronic, relapsing, and highly pruritic inflammatory skin disease affecting up to 20% of children and 1% of adults worldwide. Current evidence suggests that both impairment of epidermal barrier function and T helper 2 cell-mediated inflammatory pathway contribute to the pathogenesis of AD. Exosomes are nano-sized membrane-bound vesicles (30 – 200 nm) constantly released by almost all cells. The ability of exosomes to travel between cells and deliver genetic materials, such as microRNAs and proteins, makes them an appealing cell-free therapy option to treat multiple diseases by overcoming many drawbacks of cell-based therapy. In particular, exosomes derived from mesenchymal stem cells (MSCs) have been shown to facilitate tissue repair and regeneration, and reduce inflammation. Objective Here, we for the first time investigated whether human adipose tissue-derived mesenchymal stem cell-derived exosomes (ASC-exosomes) can ameliorate AD. Methods, Results & Conclusion Materials and Methods Human ASC-exosomes were isolated from the serum-free conditioned media by sequential filtration method and characterized as recommended by the International Society for Extracellular Vesicles (ISEV). AD-like skin lesions were induced in mice by treatment with a house dust mite antigen or a chemical irritant. Results When injected either intravenously (IV) or subcutaneously (SC) into murine model of AD, ASC-exosomes were found to significantly attenuate AD-like symptoms, such as skin lesion severity, serum IgE levels, and infiltrated mast cells. It was also found that ASC-exosomes significantly decreased mRNA levels of various inflammatory cytokines, such as interleukin (IL)-4, IL-23, IL31, and tumor necrosis factor-α (TNF-α) in AD skin lesions. Furthermore, ASC-exosomes led to the improvement of skin barrier function as evidenced by enhanced skin hydration and reduced trans-epidermal water loss (TEWL) in skin lesions. Conclusions Taken together, our data suggests that ASC-exosomes could be a novel promising cell-free therapeutic modality for AD treatment.

Plasma neuronal exosomes serve as biomarkers of cognitive impairment in HIV infection and Alzheimer's disease.

Plasma neuronal exosomes serve as biomarkers of cognitive impairment in HIV infection and Alzheimer's disease.

Essentials of extracellular vesicles: posters on basic and clinical aspects of extracellular vesicles

ABSTRACTThe past decade has witnessed an exponential development in the field of extracellular vesicles. Sporadic observations have reached a critical level and the scientific community increasingly recognizes the potential biomedical significance of these subcellular structures present in all body fluids as significant components of the cellular secretome. The Educational Committee of the International Society for Extracellular Vesicles prepared two posters (“Basic aspects of extracellular vesicles” and “Clinical aspects of extracellular vesicles”) to provide essential pieces of information on extracellular vesicles at glance for anyone not familiar with the field.

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

ABSTRACTThe last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points.

Clinical research using extracellular vesicles: insights from the International Society for Extracellular Vesicles 2018 Annual Meeting

ABSTRACTThe abstracts presented at the 2018 International Society for Extracellular Vesicles Annual Meeting offer unique insight into the newest discoveries related to the biology and applied use of extracellular vesicles (EVs). As an extension of a recent “Clinical-Wrap Up” discussion at the International Society for Extracellular Vesicles 2018 Annual Meeting, a systematic review of each abstract was performed to determine which abstracts could be considered clinical research. Once the clinical research abstracts were identified, systematic data extraction included: the major focus of each clinical research abstract; the countries in which the work was done; and the sample size, if provided in the abstract. Each abstract was reviewed by two independent authors, with a third author resolving discrepancies in cases of disagreement. 174 out of 656 (27%) unique abstracts were determined to be clinical research. Oncology was a principal research focus (51 of the 174 clinical research abstracts, 29%). Many other clinical research abstracts presented at the International Society for Extracellular Vesicles 2018 Annual Meeting focused on the use of human samples for development of methods for potential application in the clinic. Beyond oncology and methods development, a wide range of topics was represented, including cardiovascular disease, neurodegenerative disease, genetics, and many others. Current research involving EVs highlights the common, but false dichotomy of science into curiosity-driven basic science or application-driven clinical research, when in fact both quest for understanding and intent to apply the findings appeared to drive much of the work at the International Society for Extracellular Vesicles 2018 Annual Meeting. Using Pasteur’s Quadrant as a framework, we discuss where the field of EV research is heading and how we may gain insight into the biological function of EVs in tandem with how they may benefit individual health.

Towards mechanisms and standardization in extracellular vesicle and extracellular RNA studies: results of a worldwide survey

ABSTRACTThe discovery that extracellular vesicles (EVs) can transfer functional extracellular RNAs (exRNAs) between cells opened new avenues into the study of EVs in health and disease. Growing interest in EV RNAs and other forms of exRNA has given rise to research programmes including but not limited to the Extracellular RNA Communication Consortium (ERCC) of the US National Institutes of Health. In 2017, the International Society for Extracellular Vesicles (ISEV) administered a survey focusing on EVs and exRNA to canvass-related views and perceived needs of the EV research community. Here, we report the results of this survey. Overall, respondents emphasized opportunities for technical developments, unraveling of molecular mechanisms and standardization of methodologies to increase understanding of the important roles of exRNAs in the broader context of EV science. In conclusion, although exRNA biology is a relatively recent emphasis in the EV field, it has driven considerable interest and resource commitment. The ISEV community looks forward to continuing developments in the science of exRNA and EVs, but without excluding other important molecular constituents of EVs.