Outer Membrane Vesicles Derived From Escherichia coli Regulate Neutrophil Migration by Induction of Endothelial IL-8

Outer membrane vesicles (OMVs) are spherical, proteolipid nanostructures that are constitutively released by Gram-negative bacteria including Escherichia coli. Although it has been shown that administration of E. coli OMVs stimulates a strong pulmonary inflammatory response with infiltration of neutrophils into the lungs in vivo, the mechanism of E. coli OMV-mediated neutrophil recruitment is poorly characterized. In this study, we observed significant infiltration of neutrophils into the mouse lung tissues in vivo, with increased expression of the neutrophil chemoattractant CXCL1, a murine functional homolog of human IL-8, on intraperitoneal administration of E. coli OMVs. In addition, OMVs and CD31-positive endothelial cells colocalized in the mouse lungs. Moreover, in vitro results showed that E. coli OMVs significantly increased IL-8 release from human microvascular endothelial cells and toll-like receptor (TLR)4 was found to be the main component for recognizing E. coli OMVs among human endothelial cell-associated TLRs. Furthermore, the transmigration of neutrophils was suppressed in the lung tissues obtained from TLR4 knockout mice treated with E. coli OMVs. Taken together, our data demonstrated that E. coli OMVs potently recruit neutrophils into the lung via the release of IL-8/CXCL1 from endothelial cells in TLR4- and NF-κB-dependent manners

Therapeutic Effects of Autologous Tumor-Derived Nanovesicles on Melanoma Growth and Metastasis

Cancer vaccines with optimal tumor-associated antigens show promise for anti-tumor immunotherapy. Recently, nano-sized vesicles, such as exosomes derived from tumors, were suggested as potential antigen candidates, although the total yield of exosomes is not sufficient for clinical applications. In the present study, we developed a new vaccine strategy based on nano-sized vesicles derived from primary autologous tumors. Through homogenization and sonication of tumor tissues, we achieved high yields of vesicle-bound antigens. These nanovesicles were enriched with antigenic membrane targets but lacked nuclear autoantigens. Furthermore, these nanovesicles together with adjuvant activated dendritic cells in vitro, and induced effective anti-tumor immune responses in both primary and metastatic melanoma mouse models. Therefore, autologous tumor-derived nanovesicles may represent a novel source of antigens with high-level immunogenicity for use in acellular vaccines without compromising safety. Our strategy is cost-effective and can be applied to patient-specific cancer therapeutic vaccination

Кераміка «terra sigillata» з с. Зимне на Волині

Стаття присвячена публікації чотирьох керамічних посудин типу «terra sigillata», знайдених на дні р. Луги у с. Зимне Володимир-Волинського району Волинської області. Попередній аналіз цих знахідок дозволяє віднести їх до Понтійського центру виробництва такого посуду. Вірогідним шляхом потрапляння цієї колекції на Волинь була готська експансія у Північне Причорномор’я

Egr-1 activation by cancer-derived extracellular vesicles promotes endothelial cell migration via ERK1/2 and JNK signaling pathways.

Various mammalian cells, including cancer cells, shed extracellular vesicles (EVs), also known as exosomes and microvesicles, into surrounding tissues. These EVs play roles in tumor growth and metastasis by promoting angiogenesis. However, the detailed mechanism of how cancer-derived EVs elicit endothelial cell activation remains unknown. Here, we provide evidence that early growth response-1 (Egr-1) activation in endothelial cells is involved in the angiogenic activity of colorectal cancer cell-derived EVs. Both RNA interference-mediated downregulation of Egr-1 and ERK1/2 or JNK inhibitor significantly blocked EV-mediated Egr-1 activation and endothelial cell migration. Furthermore, lipid raft-mediated endocytosis inhibitor effectively blocked endothelial Egr-1 activation and migration induced by cancer-derived EVs. Our results suggest that Egr-1 activation in endothelial cells may be a key mechanism involved in the angiogenic activity of cancer-derived EVs. These findings will improve our understanding regarding the proangiogenic activities of EVs in diverse pathological conditions including cancer, cardiovascular diseases, and neurodegenerative diseases

In vivo tumor extracellular vesicles promote angiogenesis via macrophage

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X-ray imaging of various biological samples using a phase-contrast hard X-ray microscope

In this study, we visualized the internal structures of various bio-samples and found the optimum conditions of test samples for the 7 keV hard X-ray microscope of the Pohang light source. From the captured X-ray images, we could observe the intercellular and intracellular structures of dehydrated human cells and mouse tumor tissues without using any staining materials in a spatial resolution better than 100 nm. The metastasized lung tissue, which was several tens of micrometers in thickness, was found to be very well suited to this hard X-ray microscope system, because it is nearly impossible to observe such a nontransparent and thick sample with a high spatial resolution better than 100 nm using any microscopes such as a soft X-ray microscope, an optical microscope, or an electron microscope

How many beer extracellular vesicles are taken by human beings?

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Outer membrane vesicles derived from Escherichia coli up-regulate expression of endothelial cell adhesion molecules in vitro and in vivo.

Escherichia coli, as one of the gut microbiota, can evoke severe inflammatory diseases including peritonitis and sepsis. Gram-negative bacteria including E. coli constitutively release nano-sized outer membrane vesicles (OMVs). Although E. coli OMVs can induce the inflammatory responses without live bacteria, the effect of E. coli OMVs in vivo on endothelial cell function has not been previously elucidated. In this study, we show that bacteria-free OMVs increased the expression of endothelial intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1, and enhanced the leukocyte binding on human microvascular endothelial cells in vitro. Inhibition of NF-κB and TLR4 reduced the expression of cell adhesion molecules in vitro. OMVs given intraperitoneally to the mice induced ICAM-1 expression and neutrophil sequestration in the lung endothelium, and the effects were reduced in ICAM-1(-/-) and TLR4(-/-) mice. When compared to free lipopolysaccharide, OMVs were more potent in inducing both ICAM-1 expression as well as leukocyte adhesion in vitro, and ICAM-1 expression and neutrophil sequestration in the lungs in vivo. This study shows that OMVs potently up-regulate functional cell adhesion molecules via NF-κB- and TLR4-dependent pathways, and that OMVs are more potent than free lipopolysaccharide

Role of ERK1/2 and JNK signaling pathways in SW480-derived EV-mediated endothelial cell migration.

<p>(A, B) HMEC-1s were pretreated with signaling inhibitors for 1 h and then stimulated for 1 h with SW480-derived EVs (1 µg/mL). Nuclear translocation of Egr-1 protein was analyzed using confocal microscopy (n = 3). Nuclei and Egr-1 proteins were stained with Hoechst (blue) and anti-Egr-1 antibody (red), respectively. Co-localized fluorescence signals (purple) indicate the translocation of Egr-1 into the nucleus. Representative photographs are shown in panel A. The percentage of Egr-1-positive nuclei was determined by measuring the number of cells with nucleus colocalized signals over total cells (B). (C, D) Confluent HMEC-1s were scratched and treated with SW480-derived EVs (1 µg/mL) in the presence or absence of signaling inhibitors; then the number of migrated cells in the denuded zone was evaluated after 12 h (n = 3). Representative photographs of confocal microscopic imaging are shown in panel C and the number of migrated cells in the denuded zone of each group is shown in panel D. ERK1/2 inhibitor, PD98059 (20 µM); p38 MAPK inhibitor, SB203580 (10 µM); JNK inhibitor, SP600125 (20 µM); Akt inhibitor, BML-257 (20 µM). (E, F) C57BL/6 mice were subcutaneously injected with Matrigel containing SW480-derived EVs (20 µg) with PD98059 (20 µM) or SP600125 (20 µM). After 7 days, whole-mount staining of Matrigel with anti-CD31 antibody was conducted (n = 5). Representative confocal Z-stack photographs of whole mounts stained for CD31 (green) are shown in panel E. Fluorescence intensities of CD31 in the Z-stack plane of the Matrigel were measured as described in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115170#s2" target="_blank">Methods</a> (F). Scale bars in panels A, C, and E represent 30, 100, and 100 µm, respectively. Data are represented as mean ± SD. ***<i>P</i><0.001.</p

Egr-1 activation in endothelial cells by SW480-derived EVs.

<p>(A) HMEC-1s and HUVECs were incubated with SW480-derived EVs (1 µg/mL) or untreated control. mRNA was isolated from untreated control cells or cells treated with EVs for 0, 0.5, 1, 2, and 4 h and analyzed using real time RT-PCR (n = 3). Values represent Egr-1 mRNA/GAPDH mRNA normalized to untreated control cells. (B) HMEC-1s were treated with EVs (1 µg/mL) derived from HCT116 colorectal carcinoma, A549 lung adenocarcinoma, HT1080 fibrosarcoma, PC3 prostate carcinoma, SH-SY5Y neuroblastoma, and BEAS-2B normal bronchial epithelial cells for 0.5 h (n = 3). (C, D) In HMEC-1s, nuclear translocation of Egr-1 protein after stimulation with SW480-derived EVs (1 µg/mL) for 0.5, 1, 2, and 4 h was analyzed under confocal microscopy (n = 3). Nuclei and Egr-1 proteins were stained with Hoechst (blue) and anti-Egr-1 antibody (red), respectively. Co-localized fluorescence signals (purple) indicate the translocation of Egr-1 into the nucleus. Representative photographs are shown in panel C. Scale bars represent 30 µm. The percentage of Egr-1-positive nuclei was determined by measuring the number of cells with nucleus colocalized signals over that of total cells (D). Data are represented as mean ± SD. *<i>P</i><0.05; **<i>P</i><0.01; **<i>P</i><0.001; n.s., not significant.</p