Plasma-derived Extracellular Vesicles Research Articles

109 A Small RNA Signature from Extracellular Vesicles in Patient Plasma Correlates With Recurrence or Progression of High-Grade Gliomas

INTRODUCTION: Glial cell-derived tumors of the central nervous system make up the largest group of brain tumors. Most are high-grade gliomas (HGG) and are universally fatal despite multimodal therapy. In managing patients with HGG, predicting recurrence, or differentiating between pseudoprogression (radiation necrosis) and true tumor progression would be invaluable in improving overall prognosis. Characterizing small RNA (sRNA) expression profiles from plasma-derived extracellular vesicles (EVs) over the course of a patient’s treatments, may allow for patient-specific treatment modifications and improve outcomes. METHODS: Plasma EVs were isolated using Vn96 capture from HGG patients perioperatively and with routine, follow-up surveillance imaging. Small RNA sequencing was conducted and unsupervised hierarchal clustering of sRNA signatures were completed. Expression profiles were grouped longitudinally with the clinical status of patients. RESULTS: Cluster analysis of nine HGG patients, has revealed a sRNA signature that is able to distinguish between tumors showing evidence of progression and those remaining stable over time. Those samples obtained from patients where a clinical diagnosis of tumor progression or pseudoprogression were uncertain, were found to cluster into progression vs. stable signatures. Annotation of differentially expressed small RNAs identified from stable vs. clinically progressed patient include small nuclear RNA, ribosomal RNA, and micro RNA among others. MiRNA species we have identified correspond to previously identified miRNA, which have been ascribed functional significance to HGG aggressiveness and progression. CONCLUSIONS: These preliminary findings demonstrate the potential utility of sRNA profiling of plasma-derived EVs obtained from patients with high-grade gliomas as non-invasive biomarkers for recurrent/progressive disease or stability/pseudoprogression.

Characterization and Proteomic Analysis of Plasma EVs Recovered from Healthy and Diseased Dogs with Canine Leishmaniosis.

Dogs are highly valued companions and work animals that are susceptible to many life-threatening conditions such as canine leishmaniosis (CanL). Plasma-derived extracellular vesicles (EVs), exploited extensively in biomarker discovery, constitute a mostly untapped resource in veterinary sciences. Thus, the definition of proteins associated with plasma EVs recovered from healthy and diseased dogs with a relevant pathogen would be important for biomarker development. For this, we recovered, using size-exclusion chromatography (SEC), EVs from 19 healthy and 20 CanL dogs' plasma and performed proteomic analysis by LC-MS/MS to define their core proteomic composition and search for CanL-associated alterations. EVs-specific markers were identified in all preparations and also non-EVs proteins. Some EVs markers such as CD82 were specific to the healthy animals, while others, such as the Integrin beta 3 were identified in most samples. The EVs-enriched preparations allowed the identification of 529 canine proteins that were identified in both groups, while 465 and 154 were only identified in healthy or CanL samples, respectively. A GO enrichment analysis revealed few CanL-specific terms. Leishmania spp. protein identifications were also found, although with only one unique peptide. Ultimately, CanL-associated proteins of interest were identified and a core proteome was revealed that will be available for intra- and inter-species comparisons.

CXCL8 delivered by plasma-derived exosomes induces the symptoms of post-traumatic stress disorder through facilitating astrocyte-neuron communication

Extracellular vesicles (EVs) play an important role in post-traumatic stress disorder (PTSD). This study is aimed to investigate the possible molecular mechanism of CD63 mediating CXCL8 delivery via EVs to affect astrocyte-neuron communication in PTSD. The neuron-derived EVs (NDEVs) and astrocyte-derived EVs (ADEVs) were isolated from plasma in PTSD patients. Next, the uptake of EVs by neurons was assessed. Following determination of the interaction between CD63 and CXCL8, gain- and loss-of-function experiments were performed in astrocytes. Finally, a PTSD mouse model was established using the single prolonged stress and electric foot shock to confirm the effects of plasma-derived EVs delivering CXCL8 on anxiety- and depression-like behaviors in PTSD mice. EVs derived from plasma of PTSD patients aggravated anxiety- and depression-like behaviors in PTSD mice. CXCL8 was a key gene upregulated in both NDEVs and ADEVs from plasma of PTSD patients, which could be delivered into EVs by CD63. Meanwhile, CXCL8 was also highly expressed in plasma-derived EVs. In vivo experiments also verified that plasma-derived EVs could enhance astrocyte-neuron communication by delivering CXCL8, and silencing of CXCL8 ameliorated anxiety- and depression-like behaviors in PTSD mice. Taken together, CD63 promotes delivery of CXCL8 via EVs to induce PTSD by enhancing astrocyte-neuron communication, suggesting the potential of CD63 mediating delivery of CXCL8 via EVs as a therapeutic target for PTSD.

Expression of SPAG7 and its regulatory microRNAs in seminal plasma and seminal plasma-derived extracellular vesicles of patients with subfertility

Seminal plasma contains a variety of extracellular vesicles (EVs) that deliver RNAs including microRNAs (miRNAs) molecules. However, the roles of these EVs along with their delivered RNAs and their interactions with male infertility are not clear. Sperm-associated antigen 7 (SPAG 7) is expressed in male germ cells and plays a crucial role in several biological functions associated with sperm production and maturation. In this study, we aimed to identify the post-transcriptional regulation of SPAG7 in seminal plasma (SF-Native) and seminal plasma-derived extracellular vesicles (SF-EVs) collected from 87 men undergoing infertility treatment. Among the multiple binding sites for miRNAs within its 3’UTR of SPAG7, we identified the binding of four miRNAs (miR-15b-5p, miR-195-5p, miR-424-5p, and miR-497-5p) to the 3’UTR of SPAG7 by the dual luciferase assays. Analyzing sperm, we found reduced mRNA expression levels of SPAG7 in SF-EVs and SF-Native samples from oligoasthenozoospermic men. By contrast, two miRNAs (miR-424-5p and miR-497-5p) form the SF-Native samples, and four miRNAs (miR-195-5p, miR-424-5p, miR-497-5p, and miR-6838-5p) from the SF-EVs samples showed significantly higher expression levels in oligoasthenozoospermic men. The expression levels of miRNAs and SPAG7 were significantly correlated with basic semen parameters. These findings contribute significantly to our understanding of regulatory pathways in male fertility by showing a direct link between upregulated miRNA, notably miR-424, and downregulated SPAG7 both in seminal plasma and in plasma-derived EVs likely contributing to oligoasthenozoospermia.

Metastatic prostate cancer‐derived extracellular vesicles facilitate osteoclastogenesis by transferring the CDCP1 protein

Bone metastases are still incurable and result in the development of clinical complications and decreased survival for prostate cancer patients. Recently, a number of studies have shown that extracellular vesicles (EVs) play important roles in tumour progression. Here, we show that EVs from metastatic prostate cancer cells promote osteoclast formation in the presence of receptor activator of NF-κB ligand (RANKL). EV characterization followed by functional siRNA screening identified CUB-domain containing protein 1 (CDCP1), a transmembrane protein, as an inducer of osteoclastogenesis. Additionally, CDCP1 expression on plasma-derived EVs was upregulated in bone metastatic prostate cancer patients. Our findings elucidate the effect of EVs from metastatic prostate cancer cells on osteoclast formation, which is promoted by CDCP1 located on EVs. Furthermore, our data suggested that CDCP1 expression on EVs might be useful to detect bone metastasis of prostate cancer.

Diagnosis potential of subarachnoid hemorrhage using miRNA signatures isolated from plasma-derived extracellular vesicles.

The diagnosis and clinical management of aneurysmal subarachnoid hemorrhage (aSAH) is currently limited by the lack of accessible molecular biomarkers that reflect the pathophysiology of disease. We used microRNAs (miRNAs) as diagnostics to characterize plasma extracellular vesicles in aSAH. It is unclear whether they can diagnose and manage aSAH. Next-generation sequencing (NGS) was used to detect the miRNA profile of plasma extracellular vesicles (exosomes) in three patients with SAH and three healthy controls (HCs). We identified four differentially expressed miRNAs and validated the results using quantitative real-time polymerase chain reaction (RT-qPCR) with 113 aSAH patients, 40HCs, 20 SAH model mice, and 20 sham mice. Exosomal miRNA NGS revealed that six circulating exosomal miRNAs were differentially expressed in patients with aSAH versus HCs and that the levels of four miRNAs (miR-369-3p, miR-410-3p, miR-193b-3p, and miR-486-3p) were differentially significant. After multivariate logistic regression analysis, only miR-369-3p, miR-486-3p, and miR-193b-3p enabled prediction of neurological outcomes. In a mouse model of SAH, greater expression of miR-193b-3p and miR-486-3p remained statistically significant relative to controls, whereas expression levels of miR-369-3p and miR-410-3p were lower. miRNA gene target prediction showed six genes associated with all four of these differentially expressed miRNAs. The circulating exosomes miR-369-3p, miR-410-3p, miR-193b-3p, and miR-486-3p may influence intercellular communication and have potential clinical utility as prognostic biomarkers for aSAH patients.

Differential proteomic patterns of plasma extracellular vesicles show potential to discriminate β-thalassemia subtypes

The observed specificity of β-thalassemia-subtype phenotypes makes new diagnostic strategies that complement current screening methods necessary to determine each subtype and facilitate therapeutic regimens for different patients. Here, we performed quantitative proteomics of plasma-derived extracellular vesicles (EVs) of β-thalassemia major (TM) patients, β-thalassemia intermedia (TI) patients, and healthy controls to explore subgroup characteristics and potential biomarkers. Plasma quantitative proteomics among the same cohorts were analyzed in parallel to compare the biomarker potential of both specimens. EV proteomics showed significantly more abnormalities in immunity and lipid metabolism in TI and TM, respectively. The differential proteomic patterns of EVs were consistent with but more striking than those of plasma. Notably, we also found EV proteins to have a superior performance for discriminating β-thalassemia subtypes. These findings allowed us to propose a diagnostic model consisting of five proteins in EVs with subtyping potential, demonstrating the ability of plasma-derived EVs for the diagnosis of β-thalassemia patients.

Combination of size-exclusion chromatography and ion exchange adsorption for improving the proteomic analysis of plasma-derived extracellular vesicles.

Extracellular vesicles (EVs) are lipid membrane vesicles released by live cells that carry a variety of biomolecules, including nucleic acids, lipids, and proteins. Recently, proteins in plasma-derived EVs have emerged as novel biomarkers with essential functions in the diagnosis and prognosis of human diseases. However, the current methods of isolating EVs from plasma often lead to coisolated impurities in biological fluids. Therefore, before performing any research protocol, the process of extracting EVs from plasma for proteomic analysis must be optimized. In this study, two EV isolation strategies, size exclusion chromatography (SEC) and SEC combined with ion exchange adsorption (SEC + IEA), were compared in terms of the purity and quantity of protein in EVs. Our results demonstrated that, compared to single-step SEC, SEC combined with IEA could produce plasma-derived EVs with a higher purity by decreasing the abundance of lipoprotein. Additionally, with MS analysis, we demonstrated that the combination approach maintained the stability and improved the purity of EVs in many plasma samples. Furthermore, by combining SEC with IEA, more cancer-associated proteins were detected in the plasma of various cancer samples.

Brain-derived extracellular vesicles promote bone-fat imbalance in Alzheimer's disease.

Inadequate osteogenesis and excessive adipogenesis of bone marrow mesenchymal stem cells (BMSCs) are key factors in the pathogenesis of osteoporosis. Patients with Alzheimer's disease (AD) have a higher incidence of osteoporosis than healthy adults, but the underlying mechanism is not clear. Here, we show that brain-derived extracellular vesicles (EVs) from adult AD or wild-type mice can cross the blood-brain barrier to reach the distal bone tissue, while only AD brain-derived EVs (AD-B-EVs) significantly promote the shift of the BMSC differentiation fate from osteogenesis to adipogenesis and induce a bone-fat imbalance. MiR-483-5p is highly enriched in AD-B-EVs, brain tissues from AD mice, and plasma-derived EVs from AD patients. This miRNA mediates the anti-osteogenic, pro-adipogenic, and pro-osteoporotic effects of AD-B-EVs by inhibiting Igf2. This study identifies the role of B-EVs as a promoter of osteoporosis in AD by transferring miR-483-5p.

Vascular Cell Adhesion Molecule 1 and Adiponectin Receptor 1 in Plasma-Derived Extracellular Vesicles of Type 2 Diabetes Patients

Background: Patients with diabetes are susceptible to accelerated vascular damage associated with increased circulating extracellular vesicles (EVs) from endothelial tissue. Adiponectin is a cytokine with anti-inflammatory and insulin-sensitivity properties decreased in the plasma of patients with type 2 diabetes (T2D). This study aimed to assess the content of receptor 1 for adiponectin (AdipoR1) in both total and endothelial EVs from plasma samples of T2D patients and normoglycemic subjects. Methods: Insulin and soluble vascular endothelial molecule-1 (sVCAM-1) in plasma were measured by ELISA, and we used flow cytometry to determine the content of AdipoR1, CD106, and CD144 in plasma-derived EVs from 14 patients with diabetes and 34 normoglycemic subjects. Results: Compared to normoglycemic subjects, the percentage of vesicles CD144+ (p = 0.0041) and CD106+ (p = 0.0011) were higher in patients with diabetes. Compared to T2D patients, the percentage and medium fluorescence intensity from the total EVs/AdipoR1+ (p = 0.041 and p = 0.0220) were higher in normoglycemic subjects. Plasmatic sVCAM-1 was negatively correlated with plasma adiponectin (b = - 14.415, p < 0.0001), along with the percentage of EVs/AdipoR1+ (b = - 8.209, p = 0.001); and correlated positively with the percentage of EVs/CD144+ (b = 6.768, p < 0.0001) and HOMA-IR (b = 67.919, p < 0.0001). Conclusions: Our results show that the content of AdipoR1 in plasma-derived VEs is lower in patients with T2D than in subjects with normoglycemic. AdipoR1 content in EVs is negatively associated with the endothelial damage marker sVCAM-1 level in plasma and with the HOMA-IR value.

Angiogenic potential of plasma-derived extracellular vesicles from impaired fasting glucose patients: A pilot study

Angiogenic potential of plasma-derived extracellular vesicles from impaired fasting glucose patients: A pilot study

Effect of plasma-derived extracellular vesicles on angiogenesis and the ensuing proliferative diabetic retinopathy through a miR-30b-dependent mechanism.

Proliferative diabetic retinopathy (PDR) is a major diabetic microvascular complication, characterized by pathological angiogenesis. This study sets out to investigate the potential molecular mechanism in the angiogenesis during PDR. The expression of microRNA-30b (miR-30b) was quantified in a streptozotocin (STZ)-induced mouse model of PDR. The binding affinity between SIRT1 and miR-30b was then identified and validated. After transduction with In-miR-30b or combined with sh-SIRT1, high-glucose (HG)-induced retinal microvascular endothelial cells (RMECs) were co-cultured with extracellular vesicles (EVs) derived from the plasma of PDR mice (plasma-EVs). The proliferation and angiogenesis of RMECs were then detected in vitro. miR-30b expression was upregulated in the retinal tissue of PDR mice. SIRT1 was a target gene of miR-30b and under the negative regulation by miR-30b in RMECs. In contrast, inhibition of miR-30b resulted in elevated SIRT1 expression, thus alleviating the angiogenesis of RMECs. miR-30b was enriched in the plasma-EVs and could be delivered to RMECs, in which miR-30b exerted pro-angiogenic effects. Furthermore, inhibition of miR-30b arrested the progression of PDR in mice by promoting the expression of SIRT1. Collectively, the present study pinpointed the involvement of miR-30b delivered by plasma-EVs in PDR angiogenesis, thus laying the basis for the development of novel therapeutic targets for the treatment of PDR.

Proteomic profiling of cell line-derived extracellular vesicles to identify candidate circulatory markers for detection of gallbladder cancer.

Gallbladder cancer (GBC) is the sixth most common gastrointestinal tract cancer with a very low overall survival and poor prognosis. Profiling of cancer-derived extracellular vesicles (EVs) is an emerging strategy for identification of candidate biomarkers for the detection and prognosis of the disease. The aim of the study was to analyse the protein content from GBC cell line- derived EVs with emphasis on proteins which could be used as candidate biomarkers for the detection of GBC. NOZ and OCUG-1 cell lines were cultured and EVs were isolated from conditioned media. LC-MS/MS analysis of total EV proteins led to the identification of a total of 268 proteins in both the cell lines. Of these, 110 proteins were identified with ≥2 unique peptides with ≥2 PSMs in at least two experimental and technical replicate runs. STRING (Search Tool for the Retrieval of Interacting Genes/Proteins) database was used to perform bioinformatics analysis of 110 proteins which showed 'cell adhesion molecule binding', 'integrin binding', 'cadherin binding' among the top molecular functions and 'focal adhesion' to be among the top pathways associated with the EV proteins. A total of 42 proteins including haptoglobin (HP), pyruvate kinase (PKM), annexin A2 (ANXA2), thrombospondin 1 (THBS1), were reported to be differentially abundant in GBC tissue. Of these, 16 proteins were reported to be differentially abundant in plasma and plasma-derived EVs. We infer these proteins to be highly important to be considered as potential circulatory biomarkers for the detection of GBC. To check the validity of this hypothesis, one of the proteins, haptoglobin (HP) as a representative case, was analysed in plasma by quantitative Enzyme- linked immunosorbent assay (ELISA) and we observed its increased levels in GBC in comparison to controls (p value= 0.0063). Receiver operating characteristic (ROC) curve analysis for GBC vs controls showed an Area under the ROC Curve (AUC) of 0.8264 for HP with 22% sensitivity against 100% specificity. We propose that HP along with other candidate proteins may be further explored for their clinical application.

Comparison of Different Isolation Methods for Plasma-Derived Extracellular Vesicles in Patients with Hyperlipidemia.

Extracellular vesicles are commonly found in human body fluids and can reflect current physiological conditions of human body and act as biomarkers of disease. The quality of isolated extracellular vesicles facilitates the early diagnosis of various diseases accompanied by hyperlipidemia. Nonetheless, there are no reports on which special methods are suitable for isolating extracellular vesicles from the plasma of patients with hyperlipidemia. Thus, this study compared three different research-based extracellular vesicle isolation approaches, namely ultracentrifugation (UC), polyethylene glycol (PEG) precipitation, and size exclusion chromatography (SEC), and determined which of them was the most effective method. We selected blood samples from 12 patients with clinically diagnosed hyperlipidemia and isolated plasma-derived extracellular vesicles using three methods. The morphology of the isolated extracellular vesicles was observed using transmission electron microscopy, while the concentration was detected by asymmetric flow field-flow fractionation and multi-angle light scattering. Marker proteins were identified by Western blotting, and protein composition was evaluated by silver staining. Both determined the contaminations in the extracellular vesicle samples. The results showed that the three methods can be successfully used for the isolation of extracellular vesicles. The extracellular vesicles isolated by UC were larger in size, and the yield was much lower. Although the yield of extracellular vesicles isolated by PEG precipitation was greatly improved, the contamination was increased. Of the three methods, only the SEC-isolated extracellular vesicles were characterized by high yield and low contamination. Therefore, our data suggested that the SEC was a more ideal method for isolating extracellular vesicles from the plasma of patients with hyperlipidemia.

Parallel Detection of Single-Cells and Extracellular Vesicles from Bone Marrow and Peripheral Blood Reveals Asymmetric Immunometabolic Profile in Acute Myeloid Leukemia

Introduction. Acute myeloid leukemia (AML) is an aggressive disease with a high relapse rate. Alteration in cell metabolism and metabolic adaptation are crucial hallmarks in AML. Although several studies have addressed the metabolic profile of leukemic cells, the metabolic cross-modulation of immune cells according to their resident (bone marrow, BM) and circulating (peripheral blood, PB) status has been poorly investigated. Growing evidence has highlighted a key role for extracellular vesicles (EVs), shed from a broad variety of cells and cargo of crucial factors, in modulating several functions of leukemic cells, including bioenergetic metabolism. Again, few studies have addressed the impact of EVs in regulating the metabolism of immune cells from leukemic microenvironment. Therefore, in our work, we dissected the immunometabolic profile of immune cells and EV signature profile in parallel from BM versus PB from AML patients. Methods. BM/PB samples and plasma were collected from AML patients at diagnosis (n=40). Leukemic EVs (herein referred to as AML EVs) were purified from platelet-poor plasma BM/PB by size exclusion chromatography and ultrafiltration. MACSPlex Exosome Kit was used for screening surface EV markers. Flow cytometry-based Single Cell ENergetic metabolism by profilIng Translation inhibition (SCENITH) method was applied in fresh whole blood. In addition, BM/PB mononuclear cells from AML patients were characterized by SCENITH after co-culture with circulating AML EVs. Results. To explore the metabolic reprogramming within the leukemic immune microenvironment, we firstly applied the SCENITH method in multiple immune cell subpopulations from AML patients. In comparison with the paired PB, we observed a significant increase in glucose dependence of AML BM CD8+ T cells. By contrast, the capacity to use fatty acids and amino acids as sources for ATP production when glucose oxidation is inhibited was prominently reduced in AML BM CD8+ T cells and increased in AML PB CD8+ T cells. Also, mitochondrial dependence of CD8+ T cells was higher in the BM compartment, suggesting a switch from oxidative phosphorylation to glycolysis in circulation. Interestingly, in comparison to paired PB, only BM CD3+ and CD4+ T cells from female AML patients revealed a marked increase in their glucose dependence reporting gender-dependent metabolic differences. Towards clinically relevant implication, according to European LeukemiaNet (ELN) 2017 risk classification, SCENITH analysis showed a critical reduction in mitochondrial dependence at the expense of glycolytic capacity in circulating CD4+ T cells from favorable-risk AML compared to intermediate/adverse-risk patients. Given the immunometabolic profile between BM and PB cell compartments, we hypothesized that EVs may differentially contribute to immunometabolism according to their BM versus PB localization. Preliminarily, we explored the immune profiling of plasma-derived EVs from AML BM versus PB. We found that BM EVs exhibited higher expressions of specific markers including CD4, CD40, ROR-1 and HLA-II/-ABC compared to PB equivalents. Of note, we observed a novel link between metabolic regulation and EV profiling. Indeed, the glucose dependence of PB CD8+ T cells was negatively correlated to the expression of CD133-1 (stem cell marker) and CD209 (dendritic marker) depicted on circulating (PB) EVs. Finally, we co-cultured AML circulating EVs with BM/PB mononuclear cells from AML patients in pairs to investigate the EV's role in metabolic regulation. Notably, BM CD8+ T cells in monocultures showed a reduction in glucose dependence compared to their PB equivalents. In parallel, mitochondrial dependence was more pronounced in PB CD4+ T cells compared to other circulating immune subsets. However, PB EVs caused a metabolic shift in the PB compartment towards high glycolytic capacity in CD8+ T cells and high mitochondrial dependency in CD34+ cells suggesting an EV-driven metabolic rewiring. Apparently, the co-cultures with PB EVs did not influence the energy profile of resident (BM) immune subsets. Conclusions. Overall, this study shows the immunometabolic asymmetry orchestrated in AML at diagnosis, driven by distinct immune cell subsets according to their location (BM versus PB). We also describe the putative role of AML EVs in subverting the immune cell metabolism revealing critical implications for immunotherapy in AML.

Abstract 12075: Extracellular Vesicle Cargo Long-Noncoding RNAs Are Dynamic Biomarkers in Acute Decompensated Heart Failure

Introduction: Acute decompensation is associated with increased long-term mortality in patients with heart failure (HF). Biomarkers of acute HF that are dynamic during decongestion may provide physiologic insight for this observation. We hypothesized that long-noncoding RNAs (lncRNAs) and mRNAs in extracellular vesicles (EVs) not only mark different types of HF, but also may be dynamically altered with decongestion across physiologically important pathways. Methods: RNA sequencing was performed on plasma-derived EVs in acute HF patients (7 HFpEF; 7 HFrEF) at hospital admission (V1) and at discharge (V2) along with 9 controls without HF. Differential expression analysis was performed using DESeq2 across groups and time-points. Transcripts were prioritized by fold change (±1.5) and statistical significance (<5% FDR). We subsequently validated targets in EVs from 182 additional patients (24 control; 86 HFpEF; 72 HFrEF). Results: Between HF and control patients, 138 lncRNAs and 147 mRNAs were different (Fig a,b). LncRNAs were confirmed to be exclusively present in EVs. Of 13 targets investigated in our validation cohort, 5 lncRNAs and 6 mRNAs were significantly different between control and HF (age, sex-adjusted; Fig c). Pairwise comparisons between EV RNAs at hospital admission versus decongestion revealed a significant change in 4 lncRNAs (Fig d,e ) that was independent of weight change during hospitalization. Notably, distinct fragments derived from these transcripts were noted in HF versus control groups. Conclusions: The plasma EV transcriptome is significantly altered in patients with acute HF. Plasma EV-derived lncRNA fragments demarcate congestion and decongestion better than mRNAs, may be markers for pathophysiologically relevant pathways independent of volume status, and may provide additional prognostic information.

Highly efficient TiO2-based one-step strategy for micro volume plasma-derived extracellular vesicles isolation and multiomics sample preparation

Extracellular vesicles (EVs) released from tumor cells and tissues mediate intercellular communication and regulate various important biological processes. The characterization of EVs can provide potential diagnostic biomarkers and therapeutic targets. However, current EV enrichment and sample preparation methods for omics analysis are time-consuming and costly, and a relatively large amount of samples is often required. Here, we report a robust TiO2-mediated multiomics EV preparation method (TiMMEP) for isolating EVs from a small volume of plasma and profiling proteins and metabolites simultaneously. Plasma EVs were initially captured by TiO2, and EVs proteins and metabolites were released by adding 70% acetonitrile. Subsequently, the proteins were precipitated and adsorbed on the surface of TiO2 and the metabolites were collected in the supernatant. More than 700 protein groups and 491 tentatively annotated metabolites were identified in the EVs isolated from 1 μL of plasma. Furthermore, the TiMMEP method was applied for multi-omics EV analysis of ten healthy human plasma samples to demonstrate its feasibility and stability. Thus, the TiMMEP strategy enables a highly sensitive, operationally simple, and high-throughput multiomics analysis of EVs from low volume of plasma, potentially improving disease diagnosis and biomarker discovery.

Identification of an Inflammatory Biomarker Signature in Plasma-Derived Extracellular Vesicles of Glioblastoma Patients

Abstract AIMS Description of effective biomarkers present in biofluids could prove invaluable in GBM diagnosis. Extracellular vesicles (EVs) are essential to intercellular crosstalk in the tumour bulk and circulating EVs have been described as a potential reservoir of GBM biomarkers. Therefore, EV-based liquid biopsies have been suggested as a promising tool for GBM METHOD Ethical approval was obtained for a prospective study of healthy donors and consenting GBM patients at the University Hospitals Sussex (Brighton). To identify GBM specific proteins, small EVs (sEVs) were isolated from plasma samples using differential ultracentrifugation and validated through Nanoparticles tracking analysis, transmission electron microscopy and detection of known sEVs markers such as CD9, CD63, CD81 and HSP70. sEVs content was characterised through mass spectrometry and bioinformatic tools. RESULTS Our data indicate the presence of a GBM inflammatory biomarker signature comprising members of the complement and regulators of inflammation and coagulation including VWF, FCGBP, C3, PROS1, and SERPINA1. Bioinformatic analysis highlighted that all potential markers exclusively identified in patient samples had already been linked with either GBM diagnosis, prognosis or associated signalling, suggesting that sEVs protein cargo could mirror the landscape of the original tumour and that selective circulating sEV-derived proteins might be used as hallmarks for GBM patients. CONCLUSION this study is a step forward in the development of a non-invasive liquid biopsy approach for the identification of valuable biomarkers that could significantly improve GBM diagnosis and, consequently, patients’ prognosis and quality of life.

Proteome profiling of whole plasma and plasma-derived extracellular vesicles facilitates the detection of tissue biomarkers in the non-obese diabetic mouse.

The mechanism by which pancreatic beta cells are destroyed in type 1 diabetes (T1D) remains to be fully understood. Recent observations indicate that the disease may arise because of different pathobiological mechanisms (endotypes). The discovery of one or several protein biomarkers measurable in readily available liquid biopsies (e.g. blood plasma) during the pre-diabetic period may enable personalized disease interventions. Recent studies have shown that extracellular vesicles (EVs) are a source of tissue proteins in liquid biopsies. Using plasma samples collected from pre-diabetic non-obese diabetic (NOD) mice (an experimental model of T1D) we addressed if combined analysis of whole plasma samples and plasma-derived EV fractions increases the number of unique proteins identified by mass spectrometry (MS) compared to the analysis of whole plasma samples alone. LC-MS/MS analysis of plasma samples depleted of abundant proteins and subjected to peptide fractionation identified more than 2300 proteins, while the analysis of EV-enriched plasma samples identified more than 600 proteins. Of the proteins detected in EV-enriched samples, more than a third were not identified in whole plasma samples and many were classified as either tissue-enriched or of tissue-specific origin. In conclusion, parallel profiling of EV-enriched plasma fractions and whole plasma samples increases the overall proteome depth and facilitates the discovery of tissue-enriched proteins in plasma. If applied to plasma samples collected longitudinally from the NOD mouse or from models with other pathobiological mechanisms, the integrated proteome profiling scheme described herein may be useful for the discovery of new and potentially endotype specific biomarkers in T1D.

878P Improved proteome coverage for cancer plasma-derived extracellular vesicles (pEVs) using high-resolution isoelectric focusing (HiRIEF) LC-MS

The pEVs have strong potential to be used as clinical biomarkers in various pathological conditions by providing unique, additional proteomics information that could not be obtained from plasma alone. Our study provides an advanced proteomics workflow for in-depth proteome profiling and detection of disease-specific proteins present in plasma and pEVs.