keyword
MENU ▼
Read by QxMD icon Read
search

Phagosome

keyword
https://www.readbyqxmd.com/read/28806745/persistent-mycobacteria-evade-an-antibacterial-program-mediated-by-phagolysosomal-tlr7-8-myd88-in-human-primary-macrophages
#1
Alexandre Gidon, Signe Elisabeth Åsberg, Claire Louet, Liv Ryan, Markus Haug, Trude Helen Flo
Pathogenic mycobacteria reside in macrophages where they avoid lysosomal targeting and degradation through poorly understood mechanisms proposed to involve arrest of phagosomal maturation at an early endosomal stage. A clear understanding of how this relates to host defenses elicited from various intracellular compartments is also missing and can only be studied using techniques allowing single cell and subcellular analyses. Using confocal imaging of human primary macrophages infected with Mycobacterium avium (Mav) we show evidence that Mav phagosomes are not arrested at an early endosomal stage, but mature to a (LAMP1+/LAMP2+/CD63+) late endosomal/phagolysosomal stage where inflammatory signaling and Mav growth restriction is initiated through a mechanism involving Toll-like receptors (TLR) 7 and 8, the adaptor MyD88 and transcription factors NF-κB and IRF-1...
August 14, 2017: PLoS Pathogens
https://www.readbyqxmd.com/read/28801234/dendritic-cells-but-not-macrophages-sense-tumor-mitochondrial-dna-for-cross-priming-through-signal-regulatory-protein-%C3%AE-signaling
#2
Meng Michelle Xu, Yang Pu, Dali Han, Yaoyao Shi, Xuezhi Cao, Hua Liang, Xiang Chen, Xiao-Dong Li, Liufu Deng, Zhijian J Chen, Ralph R Weichselbaum, Yang-Xin Fu
Inhibition of cytosolic DNA sensing represents a strategy that tumor cells use for immune evasion, but the underlying mechanisms are unclear. Here we have shown that CD47-signal regulatory protein α (SIRPα) axis dictates the fate of ingested DNA in DCs for immune evasion. Although macrophages were more potent in uptaking tumor DNA, increase of DNA sensing by blocking the interaction of SIRPα with CD47 preferentially occurred in dendritic cells (DCs) but not in macrophages. Mechanistically, CD47 blockade enabled the activation of NADPH oxidase NOX2 in DCs, which in turn inhibited phagosomal acidification and reduced the degradation of tumor mitochondrial DNA (mtDNA) in DCs...
August 2, 2017: Immunity
https://www.readbyqxmd.com/read/28778068/snx10-promotes-phagosome-maturation-in-macrophages-and-protects-mice-against-listeria-monocytogenes-infection
#3
Jun Lou, Xiawei Li, Wei Huang, Jingjing Liang, Mingzhu Zheng, Ting Xu, Jun Lyu, Dan Li, Qin Xu, Xuexiao Jin, Guotong Fu, Di Wang, Linrong Lu
Listeria monocytogenes (L. monocytogenes),which is a facultative intracellular bacterial pathogen that causes listeriosis, is widely used to study the mammalian immune response to infection. After phagocytosis by professional phagocytes, L. monocytogenes is initially contained within phagosomes, which mature into phagolysosomes, where the bacteria are degraded. Although phagocytosis and subsequent phagosome maturation is essential for the clearance of infectious microbial pathogens, the underlying regulatory mechanisms are still unclear...
July 27, 2017: Oncotarget
https://www.readbyqxmd.com/read/28765557/the-voltage-dependent-anion-channels-vdac-of-mycobacterium-avium-phagosome-are-associated-with-bacterial-survival-and-lipid-export-in-macrophages
#4
Lia Danelishvili, Jessica J J Chinison, Tuan Pham, Rashmi Gupta, Luiz E Bermudez
Mycobacterium avium subsp. hominissuis is associated with infection of immunocompromised individuals as well as patients with chronic lung disease. M. avium infects macrophages and actively interfere with the host killing machinery such as apoptosis and autophagy. Bacteria alter the normal endosomal trafficking, prevent the maturation of phagosomes and modify many signaling pathways inside of the macrophage by secreting effector molecules into the cytoplasm. To investigate whether M. avium needs to attach to the internal surface of the vacuole membrane before releasing efferent molecules, vacuole membrane proteins were purified and binding to the surface molecules present in intracellular bacteria was evaluated...
August 1, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28755428/safely-removing-cell-debris-with-lc3-associated-phagocytosis
#5
REVIEW
Gholamreza Fazeli, Ann Marie Wehman
Phagocytosis and autophagy are two distinct pathways that degrade external and internal unwanted particles. Both pathways lead to lysosomal degradation inside the cell, and over the last decade, the line between them has blurred; autophagy proteins were discovered on phagosomes engulfing foreign bacteria, leading to the proposal of LC3-associated phagocytosis (LAP). Many proteins involved in macroautophagy are used for phagosome degradation, although Atg8/LC3 family proteins only decorate the outer membrane of LC3-associated phagosomes, in contrast to both autophagosome membranes...
July 28, 2017: Biology of the Cell
https://www.readbyqxmd.com/read/28754039/nanodiamond-chymotrypsin-and-nanodiamond-papain-conjugates-their-synthesis-and-activity-and-visualization-of-their-interaction-with-cells-using-optical-and-electron-microscopy
#6
Sergey A Golyshev, Anna K Berkovich, Ruslan Yu Yakovlev, Dmitry M Bystrov, Nikita M Ivanov, Galina N Balandina, Galina N Rudenskaya
Two novel conjugates of detonation nanodiamonds (dNDs) with the proteolytic enzymes chymotrypsin and papain were synthesized. The synthesis was performed via functionalization of the dNDs' surface with acidic/alkali treatment followed by carbodiimide-mediated protein binding. Covalent binding of the enzymes was confirmed by Fourier transform infrared spectrographic analysis and high-performance liquid chromatography (HPLC) amino acid analysis. HPLC also proved the preservation of the enzymes' composition during synthesis...
July 28, 2017: Biointerphases
https://www.readbyqxmd.com/read/28747072/regulation-of-staphylococcus-aureus-infection-of-macrophages-by-cd44-reactive-oxygen-species-and-acid-sphingomyelinase
#7
Cao Li, Yuqing Wu, Veronique Orian-Rousseau, Yang Zhang, Erich Gulbins, Heike Grassme
AIMS: Staphylococcus aureus plays an important role in sepsis, pneumonia, and wound infections. Acid sphingomyelinase (Asm)-deficient mice are highly susceptible to pulmonary S. aureus infections. Here, we investigated the role of CD44 as a molecule that mediates important aspects of the infection of macrophages with S. aureus. RESULTS: We showed that CD44 activation by S. aureus stimulated Asm via the formation of reactive oxygen species (ROS), resulting in ceramide release, clustering of CD44 in ceramide-enriched membrane platforms, CD44/Asm-dependent activation of Rho family GTPases, translocation of phospho-ezrin/radixin/moesin to the plasma-membrane, and a rapid rearrangement of the actin cytoskeleton with cortical actin polymerization...
July 26, 2017: Antioxidants & Redox Signaling
https://www.readbyqxmd.com/read/28741645/inflammasome-and-autophagy-regulation-a-two-way-street
#8
Qian Sun, Jie Fan, Timothy R Billiar, Melanie J Scott
Inflammation plays a significant role in protecting hosts against pathogens. Inflammation induced by non-infectious, endogenous agents can be detrimental, and if excessive can result in organ and tissue damage. The inflammasome is a major innate immune pathway that can be activated via both exogenous pathogen-associated molecular patterns (PAMPs) and endogenous damage-associated molecular patterns (DAMPs). Inflammasome activation involves formation and oligomerization of a protein complex including a NOD-like receptor (NLR), an adaptor protein (ASC) and procaspase-1...
July 24, 2017: Molecular Medicine
https://www.readbyqxmd.com/read/28739830/complement-c3-as-a-prompt-for-human-macrophage-death-during-infection-with-francisella-tularensis-strain-schu-s4
#9
Susan R Brock, Michael J Parmely
Tularemia is caused by the gram-negative bacterial pathogen Francisella tularensis Infection of macrophages and their subsequent death are believed to play important roles in the progression of disease. Because complement is a particularly effective opsonin for Francisella, we asked whether complement-dependent uptake of F. tularensis strain SCHU S4 affects the survival of primary human macrophages during infection. Complement component C3 was found to be an essential opsonin in human serum not only for greatly increased uptake of SCHU S4, but for the induction of macrophage death...
July 24, 2017: Infection and Immunity
https://www.readbyqxmd.com/read/28730976/salmonella-intracellular-lifestyles-and-their-impact-on-host-to-host-transmission
#10
M Graciela Pucciarelli, Francisco García-Del Portillo
More than a century ago, infections by Salmonella were already associated with foodborne enteric diseases with high morbidity in humans and cattle. Intestinal inflammation and diarrhea are hallmarks of infections caused by nontyphoidal Salmonella serovars, and these pathologies facilitate pathogen transmission to the environment. In those early times, physicians and microbiologists also realized that typhoid and paratyphoid fever caused by some Salmonella serovars could be transmitted by "carriers," individuals outwardly healthy or at most suffering from some minor chronic complaint...
July 2017: Microbiology Spectrum
https://www.readbyqxmd.com/read/28725638/isolation-of-f-novicida-containing-phagosome-from-infected-human-monocyte-derived-macrophages
#11
Valentina Marecic, Olga Shevchuk, Mateja Ozanic, Mirna Mihelcic, Michael Steinert, Antonija Jurak Begonja, Yousef Abu Kwaik, Marina Santic
Francisella is a gram-negative bacterial pathogen, which causes tularemia in humans and animals. A crucial step of Francisella infection is its invasion of macrophage cells. Biogenesis of the Francisella-containing phagosome (FCP) is arrested for ~15 min at the endosomal stage, followed by gradual bacterial escape into the cytosol, where the microbe proliferates. The crucial step in pathogenesis of tularemia is short and transient presence of the bacterium within phagosome. Isolation of FCPs for further studies has been challenging due to the short period of time of bacterial residence in it and the characteristics of the FCP...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/28724916/involvement-of-the-p62-nrf2-signal-transduction-pathway-on-erythrophagocytosis
#12
Inês B Santarino, Michelle S Viegas, Neuza S Domingues, Ana M Ribeiro, Miguel P Soares, Otília V Vieira
Erythrophagocytosis, the phagocytic removal of damaged red blood cells (RBC), and subsequent phagolysosome biogenesis are important processes in iron/heme metabolism and homeostasis. Phagolysosome biogenesis implies the interaction of nascent phagosomes with endocytic compartments and also autophagy effectors. Here, we report that besides recruitment of microtubule-associated protein-1-light chain 3 (LC3), additional autophagy machinery such as sequestosome 1 (p62) is also acquired by single-membrane phagosomes at very early stages of the phagocytic process and that its acquisition is very important to the outcome of the process...
July 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28719821/bcg-old-workhorse-new-skills
#13
REVIEW
M Gengenbacher, N E Nieuwenhuizen, She Kaufmann
Bacille Calmette-Guérin (BCG), the only tuberculosis (TB) vaccine in clinical practice, has limitations in efficacy, immunogenicity and safety. Much current TB vaccine research focuses on engineering live mycobacteria to interfere with phagosome biology and host intracellular pathways including apoptosis and autophagy, with candidates such as BCG Δzmp1, BCG ΔureC::hly, BCG::ESX-1(Mmar), Mtb ΔphoP ΔfadD26, Mtb ΔRD1 ΔpanCD and M. smegmatis Δesx-3::esx-3(Mtb) in the development pipeline. Correlates of protection in preclinical studies include increased central memory CD4(+) T cells and recruitment of antigen-specific T cells to the lungs, with mucosal vaccination found to be superior to parenteral vaccination...
July 15, 2017: Current Opinion in Immunology
https://www.readbyqxmd.com/read/28708252/redundant-and-regulatory-roles-for-tlrs-in-leishmania-infection
#14
REVIEW
Prashant Chauhan, Divanshu Shukla, Debprasad Chattopadhyay, Bhaskar Saha
Toll-like receptors (TLRs) are germ-line encoded, non-clonal innate immune receptors, which are often the first receptors to recognize the molecular patterns on pathogens. Therefore, the immune response initiated by TLRs does have far-reaching consequences on the outcome of an infection. As soon as the cell surface TLRs and other receptors recognize a pathogen, the pathogen is phagocytosed. Inclusion of TLRs in the phagosome results in quicker phagosomal maturation and stronger adaptive immune response, as TLRs influence costimulatory molecules expression and determinant selection by MHC class-II and by MHC class-I for cross-presentation...
July 14, 2017: Clinical and Experimental Immunology
https://www.readbyqxmd.com/read/28707004/host-sirtuin-1-regulates-mycobacterial-immunopathogenesis-and-represents-a-therapeutic-target-against-tuberculosis
#15
Catherine Y Cheng, Nuria M Gutierrez, Mardiana B Marzuki, Xiaohua Lu, Taylor W Foreman, Bhairav Paleja, Bernett Lee, Akhila Balachander, Jinmiao Chen, Liana Tsenova, Natalia Kurepina, Karen W W Teng, Kim West, Smriti Mehra, Francesca Zolezzi, Michael Poidinger, Barry Kreiswirth, Deepak Kaushal, Hardy Kornfeld, Evan W Newell, Amit Singhal
Mycobacterium tuberculosis (Mtb) executes a plethora of immune-evasive mechanisms, which contribute to its pathogenesis, limited efficacy of current therapy, and the emergence of drug-resistant strains. This has led to resurgence in attempts to develop new therapeutic strategies/targets against tuberculosis (TB). We show that Mtb down-regulates sirtuin 1 (SIRT1), a nicotinamide adenine dinucleotide (NAD(+))-dependent deacetylase, in monocytes/macrophages, TB animal models, and TB patients with active disease...
March 2017: Science Immunology
https://www.readbyqxmd.com/read/28701506/modelling-the-host-pathogen-interactions-of-macrophages-and-candida-albicans-using-game-theory-and-dynamic-optimization
#16
Sybille Dühring, Jan Ewald, Sebastian Germerodt, Christoph Kaleta, Thomas Dandekar, Stefan Schuster
The release of fungal cells following macrophage phagocytosis, called non-lytic expulsion, is reported for several fungal pathogens. On one hand, non-lytic expulsion may benefit the fungus in escaping the microbicidal environment of the phagosome. On the other hand, the macrophage could profit in terms of avoiding its own lysis and being able to undergo proliferation. To analyse the causes of non-lytic expulsion and the relevance of macrophage proliferation in the macrophage-Candida albicans interaction, we employ Evolutionary Game Theory and dynamic optimization in a sequential manner...
July 2017: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/28700741/mononuclear-macrophages-but-not-neutrophils-act-as-major-infiltrating-anti-leptospiral-phagocytes-during-leptospirosis
#17
Xu Chen, Shi-Jun Li, David M Ojcius, Ai-Hua Sun, Wei-Lin Hu, Xu'ai Lin, Jie Yan
OBJECTIVE: To identify the major infiltrating phagocytes during leptospirosis and examine the killing mechanism used by the host to eliminate Leptospira interrogans. METHODS: Major infiltrating phagocytes in Leptospira-infected C3H/HeJ mice were detected by immunohistochemistry. Chemokines and vascular endothelial cell adhesion molecules (VECAMs) of Leptospira-infected mice and leptospirosis patients were detected by microarray and immunohistochemistry. Leptospira-phagocytosing and -killing abilities of human or mouse macrophages and neutrophils, and the roles of intracellular ROS, NO and [Ca2+]i in Leptospira-killing process were evaluated by confocal microscopy and spectrofluorimetry...
2017: PloS One
https://www.readbyqxmd.com/read/28698569/ahpc-of-the-mycobacterial-antioxidant-defense-system-and-its-interaction-with-its-reducing-partner-thioredoxin-c
#18
Chui Fann Wong, Joon Shin, Malathy Sony Subramanian Manimekalai, Wuan Geok Saw, Zhan Yin, Shashi Bhushan, Arvind Kumar, Priya Ragunathan, Gerhard Grüber
Despite the highly oxidative environment of the phagosomal lumen, the need for maintaining redox homeostasis is a critical aspect of mycobacterial biology. The pathogens are equipped with the sophisticated thioredoxin- (Trx) and peroxiredoxin system, including TrxC and the alkyl hydroperoxide reductase subunit C (AhpC), whereby TrxC is one of the reducing partners of AhpC. Here we visualize the redox modulated dodecamer ring formation of AhpC from Mycobacterium bovis (BCG strain; MbAhpC) using electron microscopy and present novel insights into the unique N-terminal epitope (40 residues) of mycobacterial AhpC...
July 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28696299/polar-delivery-of-legionella-type-iv-secretion-system-substrates-is-essential-for-virulence
#19
Kwangcheol C Jeong, Debnath Ghosal, Yi-Wei Chang, Grant J Jensen, Joseph P Vogel
A recurrent emerging theme is the targeting of proteins to subcellular microdomains within bacterial cells, particularly to the poles. In most cases, it has been assumed that this localization is critical to the protein's function. Legionella pneumophila uses a type IVB secretion system (T4BSS) to export a large number of protein substrates into the cytoplasm of host cells. Here we show that the Legionella export apparatus is localized to the bacterial poles, as is consistent with many T4SS substrates being retained on the phagosomal membrane adjacent to the poles of the bacterium...
July 25, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28692419/long-term-cigarette-smoke-exposure-and-changes-in-mirna-expression-and-proteome-in-non-small-cell-lung-cancer
#20
Jayshree Advani, Yashwanth Subbannayya, Krishna Patel, Aafaque Ahmad Khan, Arun H Patil, Ankit P Jain, Hitendra S Solanki, Aneesha Radhakrishnan, Sneha M Pinto, Nandini A Sahasrabuddhe, Joji K Thomas, Premendu P Mathur, Bipin G Nair, Xiaofei Chang, T S Keshava Prasad, David Sidransky, Harsha Gowda, Aditi Chatterjee
Chronic exposure to cigarette smoke markedly increases the risk for lung cancer. Regulation of gene expression at the post-transcriptional level by miRNAs influences a variety of cancer-related interactomes. Yet, relatively little is known on the effects of long-term cigarette smoke exposure on miRNA expression and gene regulation. NCI-H292 (H292) is a cell line sensitive to cigarette smoke with mucoepidermoid characteristics in culture. We report, in this study, original observations on long-term (12 months) cigarette smoke effects in the H292 cell line, using microarray-based miRNA expression profiling, and stable isotopic labeling with amino acids in cell culture-based quantitative proteomic analysis...
July 2017: Omics: a Journal of Integrative Biology
keyword
keyword
23212
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"