keyword
MENU ▼
Read by QxMD icon Read
search

OMV

keyword
https://www.readbyqxmd.com/read/28794055/effect-of-vaccine-elicited-antibodies-on-colonization-of-neisseria-meningitidis-serogroup-b-and-c-strains-in-a-human-bronchial-epithelial-cell-culture-model
#1
Vianca Vianzon, Beate Illek, Gregory R Moe
Capsular polysaccharide-protein conjugate vaccines protect individuals from invasive disease and decrease carriage, which reduces spread of the organism in the population. In contrast, antibodies elicited by plain polysaccharide or protein antigen-based meningococcal (Men) vaccines have little or no effect on decreasing carriage. In this study, we investigated the mechanism by which vaccine-induced human IgG antibodies affect colonization by serogroup B (MenB) or C (MenC) strains using a human bronchial epithelial cell culture model (16HBE14o-)...
August 9, 2017: Clinical and Vaccine Immunology: CVI
https://www.readbyqxmd.com/read/28790210/membrane-distribution-of-the-pseudomonas-quinolone-signal-modulates-outer-membrane-vesicle-production-in-pseudomonas%C3%A2-aeruginosa
#2
Catalina Florez, Julie E Raab, Adam C Cooke, Jeffrey W Schertzer
The Pseudomonas quinolone signal (PQS) is an important quorum-sensing molecule in Pseudomonas aeruginosa that also mediates its own packaging and transport by stimulating outer membrane vesicle (OMV) formation. Because OMVs have been implicated in many virulence-associated behaviors, it is critical that we understand how they are formed. Our group proposed the bilayer-couple model for OMV biogenesis, where PQS intercalates into the outer membrane, causing expansion of the outer leaflet and consequently inducing curvature...
August 8, 2017: MBio
https://www.readbyqxmd.com/read/28770026/neisseria-lactamica-y92-1009-complete-genome-sequence
#3
Anish K Pandey, David W Cleary, Jay R Laver, Martin C J Maiden, Xavier Didelot, Andrew Gorringe, Robert C Read
We present the high quality, complete genome assembly of Neisseria lactamica Y92-1009 used to manufacture an outer membrane vesicle (OMV)-based vaccine, and a member of the Neisseria genus. The strain is available on request from the Public Health England Meningococcal Reference Unit. This Gram negative, dipplococcoid bacterium is an organism of worldwide clinical interest because human nasopharyngeal carriage is related inversely to the incidence of meningococcal disease, caused by Neisseria meningitidis. The organism sequenced was isolated during a school carriage survey in Northern Ireland in 1992 and has been the subject of a variety of laboratory and clinical studies...
2017: Standards in Genomic Sciences
https://www.readbyqxmd.com/read/28768669/immunogenicity-of-nontypeable-haemophilus-influenzae-outer-membrane-vesicles-and-protective-ability-in-the-chinchilla-model-of-otitis-media
#4
Linda E Winter, Stephen J Barenkamp
Outer membrane vesicles (OMVs) produced by Gram-negative bacteria are enriched in several outer membrane components, including major and minor outer membrane proteins and lipooligosaccharide. We assessed the functional activity of nontypeable Haemophilus influenzae (NTHi) OMV-specific antisera and the protective ability of NTHi OMVs as vaccine antigens in the chinchilla otitis media model. OMVs were purified from three HMW1/HMW2-expressing NTHi strains, two of which were also engineered to overexpress Hia proteins...
August 2, 2017: Clinical and Vaccine Immunology: CVI
https://www.readbyqxmd.com/read/28765539/bacterial-membrane-vesicles-transport-their-dna-cargo-into-host-cells
#5
Natalie J Bitto, Ross Chapman, Sacha Pidot, Adam Costin, Camden Lo, Jasmine Choi, Tanya D'Cruze, Eric C Reynolds, Stuart G Dashper, Lynne Turnbull, Cynthia B Whitchurch, Timothy P Stinear, Katryn J Stacey, Richard L Ferrero
Bacterial outer membrane vesicles (OMVs) are extracellular sacs containing biologically active products, such as proteins, cell wall components and toxins. OMVs are reported to contain DNA, however, little is known about the nature of this DNA, nor whether it can be transported into host cells. Our work demonstrates that chromosomal DNA is packaged into OMVs shed by bacteria during exponential phase. Most of this DNA was present on the external surfaces of OMVs, with smaller amounts located internally. The DNA within the internal compartments of Pseudomonas aeruginosa OMVs were consistently enriched in specific regions of the bacterial chromosome, encoding proteins involved in virulence, stress response, antibiotic resistance and metabolism...
August 1, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28752705/-bacterial-outer-membrane-vesicles-as-nano-carriers-to-study-immunological-activities
#6
Chen Qi, W U Min, Bai Hongzhen, Guo Zeling, Zhou Jun, Wang Qingqing, Tang Guping
Objective: To prepare a nano-carrier based on combining bacterial outer membrane vesicles (OMV) with three block polymer pluronic F127 (PEO100-PPO65-PEO100) (OMV-F127) and to investigate its immunological activity. Methods: Attenuated salmonella (sal) was cultivated. OMV were separated by centrifugal ultrafiltration or ultrasonication, and OMV-F127 was prepared by mechanical extrudation method. The protein contents and compositions were tested with BCA and SDS-PAGE; the morphology of OMV, F127 and OMV-F127 were observed with FM and TEM; the particle sizes and their zeta potential were determined with DLS...
March 25, 2017: Zhejiang da Xue Xue Bao. Yi Xue Ban, Journal of Zhejiang University. Medical Sciences
https://www.readbyqxmd.com/read/28745825/salmonella-choleraesuis-outer-membrane-vesicles-proteomics-and-immunogenicity
#7
Qiong Liu, Jie Yi, Kang Liang, Xiangmin Zhang, Qing Liu
Salmonella enterica serotype Choleraesuis (S. Choleraesuis), Gram-negative facultative intracellular pathogen is capable of inducing the cholera in pigs whose symptoms manifest as fever, depression, septicemia, arthritis, and diarrhea. Infections with S. Choleraesuis has resulted in great economic loss for the swine breeding operations. Bacterial outer membrane vesicles (OMVs) play an important role in pathogenicity and host-pathogen interaction. In this study, we purified OMVs released by S. Choleraesuis strain χ3545 and characterized their lipopolysaccharide (LPS) profile...
July 26, 2017: Journal of Basic Microbiology
https://www.readbyqxmd.com/read/28745311/outer-membrane-vesicle-associated-lipase-ftla-enhances-cellular-invasion-and-virulence-in-francisella-tularensis-lvs
#8
Fei Chen, Guolin Cui, Shuxia Wang, Manoj Kumar Mohan Nair, Lihong He, Xinyi Qi, Xiangmin Han, Hanqi Zhang, Jing-Ren Zhang, Jingliang Su
Francisella tularensis is a highly infectious intracellular pathogen that infects a wide range of host species and causes fatal pneumonic tularemia in humans. ftlA was identified as a potential virulence determinant of the F. tularensis live vaccine strain (LVS) in our previous transposon screen, but its function remained undefined. Here, we show that an unmarked deletion mutant of ftlA was avirulent in a pneumonia mouse model with a severely impaired capacity to infect host cells. Consistent with its sequence homology with GDSL lipase/esterase family proteins, the FtlA protein displayed lipolytic activity in both E...
July 26, 2017: Emerging Microbes & Infections
https://www.readbyqxmd.com/read/28744268/intestinal-anti-inflammatory-effects-of-outer-membrane-vesicles-from-escherichia-coli-nissle-1917-in-dss-experimental-colitis-in-mice
#9
María-José Fábrega, Alba Rodríguez-Nogales, José Garrido-Mesa, Francesca Algieri, Josefa Badía, Rosa Giménez, Julio Gálvez, Laura Baldomà
Escherichia coli Nissle 1917 (EcN) is a probiotic strain with proven efficacy in inducing and maintaining remission of ulcerative colitis. However, the microbial factors that mediate these beneficial effects are not fully known. Gram-negative bacteria release outer membrane vesicles (OMVs) as a direct pathway for delivering selected bacterial proteins and active compounds to the host. In fact, vesicles released by gut microbiota are emerging as key players in signaling processes in the intestinal mucosa. In the present study, the dextran sodium sulfate (DSS)-induced colitis mouse model was used to investigate the potential of EcN OMVs to ameliorate mucosal injury and inflammation in the gut...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28740179/legionella-pneumophila-infection-activates-bystander-cells-differentially-by-bacterial-and-host-cell-vesicles
#10
Anna Lena Jung, Christina Elena Herkt, Christine Schulz, Kathrin Bolte, Kerstin Seidel, Nicoletta Scheller, Alexandra Sittka-Stark, Wilhelm Bertrams, Bernd Schmeck
Extracellular vesicles from eukaryotic cells and outer membrane vesicles (OMVs) released from gram-negative bacteria have been described as mediators of pathogen-host interaction and intercellular communication. Legionella pneumophila (L. pneumophila) is a causative agent of severe pneumonia. The differential effect of bacterial and host cell vesicles in L. pneumophila infection is unknown so far. We infected THP-1-derived or primary human macrophages with L. pneumophila and isolated supernatant vesicles by differential centrifugation...
July 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28721849/effective-protection-of-mice-against-shigella-flexneri-with-a-new-self-adjuvant-multicomponent-vaccine
#11
Yadira Pastor, Ana Camacho, Ana Gloria Gil, Rocío Ramos, Adela López de Ceráin, Iván Peñuelas, Juan M Irache, Carlos Gamazo
PURPOSE: The aim of this study was to develop an immunogenic protective product against Shigella flexneri by employing a simple and safe heat treatment-based strategy. METHODOLOGY: The physicochemical characteristics of naturally produced (OMV) and heat-induced (HT) outer-membrane vesicles from S. flexneri were examined, including a comparison of the protein content of the products. Toxicological and biodistribution studies, and a preliminary experiment to examine the protective effectiveness of HT in a murine model of S...
July 2017: Journal of Medical Microbiology
https://www.readbyqxmd.com/read/28717425/high-throughput-nanoparticle-tracking-analysis-for-monitoring-outer-membrane-vesicle-production
#12
Matthias J H Gerritzen, Dirk E Martens, René H Wijffels, Michiel Stork
Outer membrane vesicles (OMVs) are spherical membrane nanoparticles released by Gram-negative bacteria. OMVs can be quantified in complex matrices by nanoparticle tracking analysis (NTA). NTA can be performed in static mode or with continuous sample flow that results in analysis of more particles in a smaller time-frame. Flow measurements must be performed manually despite the availability of a sample changer on the NanoSight system. Here we present a method for automated measurements in flow mode. OMV quantification in flow mode results in lower variance in particle quantification (coefficient of variation (CV) of 6%, CV static measurements of 14%)...
2017: Journal of Extracellular Vesicles
https://www.readbyqxmd.com/read/28717032/th17-mediated-cross-protection-against-pneumococcal-carriage-by-vaccination-with-a-variable-antigen
#13
Kirsten Kuipers, Wouter S P Jong, Christa E van der Gaast-de Jongh, Diane Houben, Fred van Opzeeland, Elles Simonetti, Saskia van Selm, Ronald de Groot, Marije I Koenders, Taj Azarian, Elder Pupo, Peter van der Ley, Jeroen D Langereis, Aldert Zomer, Joen Luirink, Marien I de Jonge
Serotype-specific protection against a Streptococcus pneumoniae is an important limitation of the current polysaccharide-based vaccines. To prevent serotype replacement, reduce transmission and limit emergence of new variants, it is essential to induce broad protection and restrict pneumococcal colonization. In this study, we used a prototype vaccine formulation consisting of LPS-detoxified outer membrane vesicles (OMVs) from Salmonella Typhimurium displaying the variable N-terminus of PspA (α1α2) for intranasal vaccination, which induced strong Th17 immunity associated with substantial reduction of pneumococcal colonization...
July 17, 2017: Infection and Immunity
https://www.readbyqxmd.com/read/28694488/outer-membrane-vesicles-secreted-by-pathogenic-and-nonpathogenic-bacteroides-fragilis-represent-different-metabolic-activities
#14
Natalya B Zakharzhevskaya, Anna A Vanyushkina, Ilya A Altukhov, Aleksey L Shavarda, Ivan O Butenko, Daria V Rakitina, Anastasia S Nikitina, Aleksandr I Manolov, Alina N Egorova, Eugene E Kulikov, Innokentii E Vishnyakov, Gleb Y Fisunov, Vadim M Govorun
Numerous studies are devoted to the intestinal microbiota and intercellular communication maintaining homeostasis. In this regard, vesicles secreted by bacteria represent one of the most popular topics for research. For example, the outer membrane vesicles (OMVs) of Bacteroides fragilis play an important nutritional role with respect to other microorganisms and promote anti-inflammatory effects on immune cells. However, toxigenic B. fragilis (ETBF) contributes to bowel disease, even causing colon cancer. If nontoxigenic B...
July 10, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28686482/outer-membrane-vesicles-blebbing-contributes-to-b-vulgatus-mpk-mediated-immune-response-silencing
#15
Jan Kevin Maerz, Alex Steimle, Anna Lange, Annika Bender, Birgit Fehrenbacher, Julia-Stefanie Frick
The Gram negative intestinal symbiont Bacteroides vulgatus mpk is able to prevent from induction of colonic inflammation in Rag1(-/-) mice and promotes immune balance in Il2(-/-) mice. These inflammation-silencing effects are associated with B. vulgatus mpk-mediated induction of semi-mature dendritic cells, especially in the colonic lamina propria (cLP). However the beneficial interaction of bacteria with host immune cells is limited due to the existence of a large mucus layer covering the intestinal epithelium...
July 7, 2017: Gut Microbes
https://www.readbyqxmd.com/read/28675605/intrahost-milieu-modulates-production-of-outer-membrane-vesicles-vesicle-associated-shiga-toxin-2a-and-cytotoxicity-in-escherichia-coli-o157-h7-and-o104-h4
#16
Andreas Bauwens, Lisa Kunsmann, Monika Marejková, Wenlan Zhang, Helge Karch, Martina Bielaszewska, Alexander Mellmann
Outer membrane vesicles (OMVs) are important virulence tools of enterohaemorrhagic Escherichia coli (EHEC), but other biological functions of these nanostructures are unknown. We tested the hypothesis that modulation of OMV production enables EHEC to resist the intrahost environment during infection by investigating if simulated human gastrointestinal conditions affect OMV production in EHEC O157:H7 and O104:H4. All the conditions tested including a low pH, simulated ileal and colonic media, presence of mucin, intestinal epithelial cell lysate or antimicrobial peptides, as well as iron limitation, significantly increased OMV production by these pathogens...
July 4, 2017: Environmental Microbiology Reports
https://www.readbyqxmd.com/read/28666873/overexpression-of-mica-induces-production-of-ompc-enriched-outer-membrane-vesicles-that-protect-against-salmonella-challenge
#17
Hyun-Il Choi, Moonjeong Kim, Jinseong Jeon, Jin Kwan Han, Kwang-Sun Kim
Outer membrane vesicles (OMVs) derived from bacteria are promising candidates for subunit vaccines. Stresses that modulate the composition of outer membrane proteins (OMPs) are important for OMV synthesis. Small RNAs (sRNAs) expressed in response to stress regulate OMPs, although the mechanism underlying sRNA-mediated OMV biogenesis and its utility for developing vaccine platforms remains to be elucidated. Here, we characterized the role of a sRNA, MicA, which regulates OmpA, a major OMP involved in both production of OMVs and reactive immunity against Salmonella challenge...
August 26, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28660582/single-step-capture-and-targeted-metabolomics-of-alkyl-quinolones-in-outer-membrane-vesicles-of-pseudomonas-aeruginosa
#18
Pallavi Lahiri, Dipankar Ghosh
Outer membrane vesicles (OMVs) are secreted by all Gram-ve pathogens. These nano-scale delivery vehicles contain discrete arrays of prokaryotic pathogenic determinants, including a family of low molecular weight (MW) lipidic quorum signaling alkyl-quinolones (AQs). These are synthesized from β-keto-fatty acids and function like primordial lipidic hormones, which regulate numerous pathogenic factors both inter-species and intra-species. Significantly, AQs can also directly exacerbate pathogenesis by cross-kingdom signaling with the host immune, metabolic, and other systems...
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28649237/outer-membrane-vesicles-omvs-of-gram-negative-bacteria-a-perspective-update
#19
REVIEW
Arif Tasleem Jan
Outer Membrane Vesicles (OMVs) of Gram-negative bacteria are spherical membrane-enclosed entities of endocytic origin. Reported in the consortia of different bacterial species, production of OMVs into extracellular milieu seems essential for their survival. Enriched with bioactive proteins, toxins, and virulence factors, OMVs play a critical role in the bacteria-bacteria and bacteria-host interactions. Emergence of OMVs as distinct cellular entities helps bacteria in adaptating to diverse niches, in competing with other bacteria to protect members of producer species and more importantly play a crucial role in host-pathogen interaction...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28636010/engineering-multi-functional-bacterial-outer-membrane-vesicles-as-modular-nanodevices-for-biosensing-and-bioimaging
#20
Qi Chen, Sharon Rozovsky, Wilfred Chen
Outer membrane vesicles (OMVs) are proteoliposomes derived from the outer membrane and periplasmic space of many Gram-negative bacteria including E. coli as part of their natural growth cycle. Inspired by the natural ability of E. coli to sort proteins to both the exterior and interior of OMVs, we reported here a one-pot synthesis approach to engineer multi-functionalized OMV-based sensors for both antigen binding and signal generation. SlyB, a native lipoprotein, was used a fusion partner to package nanoluciferase (Nluc) within OMVs, while a previously developed INP-Scaf3 surface scaffold was fused to the Z-domain for antibody recruiting...
July 4, 2017: Chemical Communications: Chem Comm
keyword
keyword
84093
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"