Project description:Osteolineage cells represent one of the critical bone marrow niche components that support maintenance of hematopoietic stem and progenitor cells (HSPCs). Recent studies demonstrate that extracellular vesicles (EVs) regulate stem cell development via horizontal transfer of bioactive cargo, including microRNAs (miRNAs). Here, we characterize the miRNA profile of EVs secreted by human osteoblasts and study their biological effect of on human umbilical cord blood-derived CD34+ HSPCs by sequencing, gene expression and biochemical analyses. Using next-generation sequencing we show that osteoblast-derived EVs contain highly abundant miRNAs specifically enriched in EVs, including critical regulators of hematopoietic proliferation (e.g., miR-29a). EV treatment of CD34+ HSPCs alters the expression of candidate miRNA targets, such as HBP1, BCL2 and PTEN. Furthermore, EVs enhance proliferation of CD34+ cells and their immature subsets in growth factor-driven ex vivo expansion cultures. Importantly, EV-expanded cells retain their differentiation capacity in vitro and show successful engraftment in NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice in vivo. These discoveries reveal a novel osteoblast-derived EV-mediated mechanism for regulation of HSPC proliferation and warrant consideration of EV-miRNAs for the development of expansion strategies to treat hematological disorders.
Project description:The present studies tested the hypothesis that the elongating ovine conceptus and uterus produces EVs with the potential to mediate conceptus-maternal communication during early pregnancy. In Study One, EVs were purified from uterine luminal fluid (ULF) of day 14 cyclic sheep. The EVs were fluorescently labeled with PKH67 dye and infused into the uterine lumen of pregnant sheep for 6 days using an osmotic pump. On day 14, labeled EVs were observed in the conceptus trophectoderm and uterine epithelia, but not in the uterine stroma or myometrium. In Study Two, day 14 conceptuses were cultured ex vivo for 24 hours and found to release EVs into the culture medium. Isolated EVs from conceptuses were fluorescently labeled with PKH67 and infused into the uterine lumen of cyclic sheep for 6 days using an osmotic pump. On day 14, labeled EVs were observed in the uterine epithelia, but not in the uterine stroma or myometrium. No evidence of EV escape from the uterine lumen was observed by analysis of the ovary and other maternal tissues. Proteomics analysis of the day 14 conceptus-derived EVs identified 231 proteins that were enriched for extracellular space and several protein classes including proteases, protease inhibitors, chaperones and chaperonins. RNA-sequencing of day 14 conceptus-derived EVs detected expression of 512 mRNAs. The top expressed genes were overrepresented in ribosomal functions and components. These studies support the ideas that EVs emanate from both the conceptus trophectoderm and uterine epithelia and are involved in intercellular communication during the establishment of pregnancy. Transcriptional profiles from day 14 conceptus extracellular vesicles isolated from 24 hour conceptus-conditioned culture media (n=3) were generated by sequencing on the Illumina HiSeq 2500 platform.
Project description:Phenotypic changes induced by extracellular vesicles (EVs) have been implicated in the recovery of acute kidney injury (AKI) induced by mesenchymal stromal cells (MSCs). miRNAs are potential candidates for cell reprogramming towards a pro-regenerative phenotype. The aim of the present study was to evaluate whether miRNA de-regulation inhibits the regenerative potential of MSCs and derived-EVs in a model of glycerol-induced AKI in SCID mice. For this purpose, we generated MSCs depleted of Drosha, a critical enzyme of miRNA maturation, to alter miRNA expression within MSCs and EVs. Drosha knock-down MSCs (MSC-Dsh) maintained the phenotype and differentiation capacity. They produced EVs that did not differ from those of wild type cells in quantity, surface molecule expression and internalization within renal tubular epithelial cells. However, EVs derived from MSC-Dsh (EV-Dsh) showed global down-regulation of miRNAs. Whereas, wild type MSCs and derived EVs were able to induce morphological and functional recovery in AKI, MSC-Dsh and EV-Dsh were ineffective. RNA sequencing analysis showed that genes deregulated in the kidney of AKI mice were restored by treatment with MSCs and EVs but not by MSC-Dsh and EV-Dsh. Gene Ontology analysis showed that down-regulated genes in AKI were associated with fatty acid metabolism. The up-regulated genes in AKI were involved in inflammation, ECM-receptor interaction and cell adhesion molecules. These alterations were reverted by treatment with wild type MSCs and EVs, but not by the Drosha counterparts. In conclusion, miRNA depletion in MSCs and EVs significantly reduced their intrinsic regenerative potential in AKI, suggesting a critical role of miRNAs. RNA-seq
Project description:Malignant germ-cell-tumours (GCTs) are characterised by microRNA (miRNA/miR-) dysregulation, with universal over-expression of miR-371~373 and miR-302/367 clusters regardless of patient age, tumour site, or subtype (seminoma/yolk-sac-tumour/embryonal carcinoma). These miRNAs are released into the bloodstream, presumed within extracellular-vesicles (EVs) and represent promising biomarkers. Here, we comprehensively examined the role of EVs, and their miRNA cargo, on (fibroblast/endothelial/macrophage) cells representative of the testicular GCT (TGCT) tumour microenvironment (TME). Small RNA next-generation-sequencing was performed on 34 samples, comprising representative malignant GCT cell lines/EVs and controls (testis fibroblast [Hs1.Tes] cell-line/EVs and testis/ovary samples). TME cells received TGCT co-culture, TGCT-derived EVs, and a miRNA overexpression system (miR-371a-OE) to assess functional relevance. TGCT cells secreted EVs into culture media. MiR-371~373 and miR-302/367 cluster miRNAs were overexpressed in all TGCT cells/subtypes compared with control cells and were highly abundant in TGCT-derived EVs, with miR-371a-3p/miR-371a-5p the most abundant. TGCT co-culture resulted in increased levels of miRNAs from the miR-371~373 and miR-302/367 clusters in TME (fibroblast) cells. Next, fluorescent labelling demonstrated TGCT-derived EVs were internalised by all TME (fibroblast/endothelial/macrophage) cells. TME (fibroblast/endothelial) cell treatment with EVs derived from different TGCT subtypes resulted in increased miR-371~373 and miR-302/367 miRNA levels, and other generic (eg, miR-205-5p/miR-148-3p) and subtype-specific (seminoma, eg, miR-203a-3p; yolk-sac-tumour, eg, miR-375-3p) miRNAs. MiR-371a-OE in TME cells resulted in increased collagen contraction (fibroblasts) and angiogenesis (endothelial cells), via direct mRNA downregulation and alteration of relevant pathways. TGCT cells communicate with nontumour stromal TME cells through release of EVs enriched in oncogenic miRNAs, potentially contributing to tumour progression.
Project description:Osteolineage cell-derived extracellular vesicles (EVs) play a regulatory role in hematopoiesis and have been shown to promote the ex vivo expansion of human hematopoietic stem and progenitor cells (HSPCs). Here, we demonstrate that EVs from different human osteolineage sources do not have the same HSPC expansion promoting potential. Comparison of stimulatory and non-stimulatory osteolineage EVs by next-generation sequencing and mass spectrometry analyses revealed distinct microRNA (miRNA) and protein signatures identifying EV-derived candidate regulators of ex vivo HSPC expansion. Accordingly, the treatment of umbilical cord blood-derived CD34+ HSPCs with stimulatory EVs altered HSPC transcriptome, including genes with known roles in cell proliferation. An integrative bioinformatics approach, which connects the HSPC gene expression data with the candidate cargo in stimulatory EVs, delineated the potentially targeted biological functions and pathways during hematopoietic cell expansion and development. In conclusion, our study gives novel insights into the complex biological role of EVs in osteolineage cell-HSPC crosstalk and promotes the utility of EVs and their cargo as therapeutic agents in regenerative medicine.
Project description:Background: Acute coronary syndromes (ACS) are associated with aberrant gene expression and epigenetic mechanisms. In particular, de novo DNA methylation is typically linked to gene silencing, but its role in heart disease remains not fully understood. Extracellular vesicles (EVs) are active components in cellular communication for their ability to carry a plethora of signalling biomolecules, thus representing a promising new diagnostic/therapeutic approach in cardiovascular diseases (CVDs). Indeed, there is the need of novel biomarkers for ACS prediction and timely detection. Purpose: We hypothesized that specific epigenetic signals can be carried by EVs. In this regard, we isolated and characterized circulating EVs from ACS patients and evaluated their potential role to influence DNA methylation in target cells. Methods: Circulating EVs were recovered, by ultracentrifugation, from plasma samples of 19 ACS patients and 50 healthy subjects (HS). Nanoparticle tracking analysis (NTA) and western blot (WB) were used to confirm the EVs integrity and purity. Peripheral blood mononuclear cells (PBMCs) of volunteer donors were treated with both ACS and HS derived EVs and genomic DNA was extracted to perform epigenome wide analysis through Reduced Representation Bisulfite Sequencing. ShinyGO, PANTHER, and STRING tools were interrogated to perform GO and PPI network analyses. Flow Cytometry, qRT-PCR, and WB analysis were also performed to evaluate and validate both intra-vesicular and intra-cellular signals. Results: Plasma ACS-derived EVs showed a significant up-regulation of DNA methyltransferases (DNMTs) gene expression levels as compared to HS (P<0.001). Specifically, de novo methylation transcripts, as DNMT3A and DNMT3B were significantly increased in plasma ACS-EVs. DNA methylation analysis of PBMCs from volunteer donors treated with HS- and ACS-derived EVs showed that RNF166 and CCND3 genes resulted the most hyper- and hypo-methylated, respectively, after by ACS-EV treatment. In addition, PPI network analysis specifically evidenced the subnetwork with SRC, as a hub gene, connecting it to NOTCH1, FOXO3, CDC42, IKBKG, RXRA, DGKG, known as important genes already involved in the onset of CVDs. Surprising, other novel genes, BAIAP2, SYP, CHL1, and SHB, which were hypomethylated, were found significantly overexpressed in PBMCs (P<0.005), underlying the fundamental modulating properties of EV cargo in atherosclerosis. Conclusions: These findings support the significant role of ACS plasma-derived EVs, inducing de novo DNA methylation signals, and modulating specific signaling pathways in target cells.
Project description:Extracellular vesicles (EVs) are mammalian cell-derived nano-scale structures enclosed by a lipid bilayer that were previously considered to be cell debris with little biological value. However, EVs are now recognized to possess biological function, acting as a packaging, transport and delivery mechanism by which functional molecules (i.e. miRNAs) can be transferred to target cells over some distance. To examine the miRNA from keratinocyte-derived EVs, we isolated three distinct populations of EVs from both HaCaT and primary human keratinocytes (PKCs) and characterized their biophysical, biochemical and functional features by using microscopy, immunoblotting, nanoparticle tracking, and next generation sequencing. We identified 1048; 906; and, 704 miRNAs, respectively, in apoptotic bodies (APs), microvesicles (MVs) and exosomes (EXs) released from HaCaT, and 608; 506; and, 622 miRNAs in APs, MVs and EXs released from PKCs. In which, there were 623 and 437 identified miRNAs common to three HaCaT-derived EVs and PKC-derived EVs, respectively. In addition, we found hundreds of exosomal miRNAs that were previously un-reported and that differences in the abundance levels of the identified EV miRNAs could discriminate between the three EV populations. These data contribute to EV-identified miRNA database, especially keratinocyte-derived EV miRNA content.
Project description:Healthy brain function is mediated by several complementary signalling pathways, many of which are driven by extracellular vesicles (EVs). EVs are heterogeneous in both size and cargo and are constitutively released from cells into the extracellular milieu. They are subsequently trafficked to recipient cells, whereupon their entry can modify the cellular phenotype. Here, in order to further analyse the mRNA and protein cargo of neuronal EVs, we isolated EVs by size exclusion chromatography from human induced pluripotent stem cell (iPSC)-derived neurons. Electron microscopy and dynamic light scattering revealed that the isolated EVs had a diameter of 30-100 nm. Transcriptomic and proteomics analyses of the EVs and neurons identified key molecules enriched in the EVs involved in cell surface interaction (integrins and collagens), internalisation pathways (clathrin- and caveolin-dependent), downstream signalling pathways (phospholipases, integrin-linked kinase and MAPKs), and long-term impacts on cellular development and maintenance. Overall, we show that key signalling networks and mechanisms are enriched in EVs isolated from human iPSC-derived neurons.
Project description:Patient-derived prostate fibroblast primary cultures PCF-54 and PCF-55 were established from two specimens of PC tissues. Urinary EVs were isolated from urine samples of 3 patients with PC and 2 healthy males and used for the treatment of prostate fibroblast primary cultures and normal foreskin fibroblasts. Normoxic and hypoxic EVs were isolated from cell culture medium of PC3 and LNCaP prostate cancer cell lines, cultivated in normoxic and hypoxic conditions respectively. The EV-treated fibroblasts were subjected to RNA sequencing analysis.