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alveolar macrophage extracellular vesicles

Heedoo Lee, Duo Zhang, Ziwen Zhu, Charles S Dela Cruz, Yang Jin
Intercellular communications between lung epithelial cells and alveolar macrophages play an essential role in host defense against acute lung injury. Hyperoxia-induced oxidative stress is an established model to mimic human lung injury. We show that after hyperoxia-associated oxidative stress, a large amount of extracellular vesicles (EVs) are detectable in bronchoalveolar lavage fluid (BALF) and culture medium of lung epithelial cells. Microvesicles (MVs), but not exosomes (Exos) or apoptotic bodies (Abs), are the main type of EVs found in the early stages after hyperoxia...
October 12, 2016: Scientific Reports
Daniel J Schneider, Jennifer M Speth, Marc Peters-Golden
Unconventional secretion and subsequent uptake of molecular cargo via extracellular vesicles (EVs) is an important mechanism by which cells can exert paracrine effects. While this phenomenon has been widely characterized in the context of their ability to promote inflammation, less is known about the ability of EVs to transfer immunosuppressive cargo. Maintenance of normal physiology in the lung requires suppression of potentially damaging inflammatory responses to the myriad of insults to which it is continually exposed...
2016: Frontiers in Cell and Developmental Biology
H-G Moon, Y Cao, J Yang, J H Lee, H S Choi, Y Jin
Despite decades of research, the pathogenesis of acute respiratory distress syndrome (ARDS) remains poorly understood, thus impeding the development of effective treatment. Diffuse alveolar damage (DAD) and lung epithelial cell death are prominent features of ARDS. Lung epithelial cells are the first line of defense after inhaled stimuli, such as in the case of hyperoxia. We hypothesized that lung epithelial cells release 'messenger' or signaling molecules to adjacent or distant macrophages, thereby initiating or propagating inflammatory responses after noxious insult...
December 10, 2015: Cell Death & Disease
Jaffre J Athman, Ying Wang, David J McDonald, W Henry Boom, Clifford V Harding, Pamela A Wearsch
Mycobacterium tuberculosis is an intracellular pathogen that infects lung macrophages and releases microbial factors that regulate host defense. M. tuberculosis lipoproteins and lipoglycans block phagosome maturation, inhibit class II MHC Ag presentation, and modulate TLR2-dependent cytokine production, but the mechanisms for their release during infection are poorly defined. Furthermore, these molecules are thought to be incorporated into host membranes and released from infected macrophages within exosomes, 40-150-nm extracellular vesicles that derive from multivesicular endosomes...
August 1, 2015: Journal of Immunology: Official Journal of the American Association of Immunologists
You-Sun Kim, Won-Hee Lee, Eun-Jeong Choi, Jun-Pyo Choi, Young Joo Heo, Yong Song Gho, Young-Koo Jee, Yeon-Mok Oh, Yoon-Keun Kim
Recent evidence indicates that Gram-negative bacteria-derived extracellular vesicles (EVs) in indoor dust can evoke neutrophilic pulmonary inflammation, which is a key pathology of chronic obstructive pulmonary disease (COPD). Escherichia coli is a ubiquitous bacterium present in indoor dust and secretes nanometer-sized vesicles into the extracellular milieu. In the current study, we evaluated the role of E. coli-derived EVs on the development of COPD, such as emphysema. E. coli EVs were prepared by sequential ultrafiltration and ultracentrifugation...
April 1, 2015: Journal of Immunology: Official Journal of the American Association of Immunologists
Robin Roychaudhuri, Anja H Hergrueter, Francesca Polverino, Maria E Laucho-Contreras, Kushagra Gupta, Niels Borregaard, Caroline A Owen
A disintegrin and a metalloproteinase domain (ADAM) 9 is known to be expressed by monocytes and macrophages. In this study, we report that ADAM9 is also a product of human and murine polymorphonuclear neutrophils (PMNs). ADAM9 is not synthesized de novo by circulating PMNs. Rather, ADAM9 protein is stored in the gelatinase and specific granules and the secretory vesicles of human PMNs. Unstimulated PMNs express minimal quantities of surface ADAM9, but activation of PMNs with degranulating agonists rapidly (within 15 min) increases PMN surface ADAM9 levels...
September 1, 2014: Journal of Immunology: Official Journal of the American Association of Immunologists
Jens Jäger, Sebastian Marwitz, Jana Tiefenau, Janine Rasch, Olga Shevchuk, Christian Kugler, Torsten Goldmann, Michael Steinert
Histological and clinical investigations describe late stages of Legionnaires' disease but cannot characterize early events of human infection. Cellular or rodent infection models lack the complexity of tissue or have nonhuman backgrounds. Therefore, we developed and applied a novel model for Legionella pneumophila infection comprising living human lung tissue. We stimulated lung explants with L. pneumophila strains and outer membrane vesicles (OMVs) to analyze tissue damage, bacterial replication, and localization as well as the transcriptional response of infected tissue...
January 2014: Infection and Immunity
Y-S Kim, E-J Choi, W-H Lee, S-J Choi, T-Y Roh, J Park, Y-K Jee, Z Zhu, Y-Y Koh, Y S Gho, Y-K Kim
BACKGROUND: Many bacterial components in indoor dust can evoke inflammatory pulmonary diseases. Bacteria secrete nanometre-sized vesicles into the extracellular milieu, but it remains to be determined whether bacteria-derived extracellular vesicles in indoor dust are pathophysiologically related to inflammatory pulmonary diseases. OBJECTIVE: To evaluate whether extracellular vesicles (EV) in indoor air are related to the pathogenesis of pulmonary inflammation and/or asthma...
April 2013: Clinical and Experimental Allergy: Journal of the British Society for Allergy and Clinical Immunology
Teresa Repasy, Jinhee Lee, Simeone Marino, Nuria Martinez, Denise E Kirschner, Gregory Hendricks, Stephen Baker, Andrew A Wilson, Darrell N Kotton, Hardy Kornfeld
We previously reported that Mycobacterium tuberculosis triggers macrophage necrosis in vitro at a threshold intracellular load of ~25 bacilli. This suggests a model for tuberculosis where bacilli invading lung macrophages at low multiplicity of infection proliferate to burst size and spread to naïve phagocytes for repeated cycles of replication and cytolysis. The current study evaluated that model in vivo, an environment significantly more complex than in vitro culture. In the lungs of mice infected with M...
February 2013: PLoS Pathogens
M-R Kim, S-W Hong, E-B Choi, W-H Lee, Y-S Kim, S G Jeon, M H Jang, Y S Gho, Y-K Kim
BACKGROUND: Recent evidence indicates that Staphylococcus aureus, one of the most important human pathogens, secretes vesicles into the extracellular milieu. OBJECTIVE: To evaluate whether inhalation of S. aureus-derived extracellular vesicles (EV) is causally related to the pathogenesis of inflammatory pulmonary diseases. METHODS: Staphylococcus aureus EV were prepared by sequential ultrafiltration and ultracentrifugation. The innate immune response was evaluated in vitro after the application of EV to airway epithelial cells and alveolar macrophages...
October 2012: Allergy
Motao Zhu, Xin Tian, Xiao Song, Yiye Li, Yanhua Tian, Yuliang Zhao, Guangjun Nie
The mechanisms associated with the induction of systemic immune responses by nanoparticles are not fully understood, but their elucidation is critical to address safety issues associated with the broader medical application of nanotechnology. In this study, a key role of nanoparticle-induced exosomes (extracellularly secreted membrane vesicles) as signaling mediators in the induction of T helper cell type 1 (Th1) immune activation is demonstrated. In vivo exposure to magnetic iron oxide nanoparticles (MIONs) results in significant exosome generation in the alveolar region of Balb/c mice...
September 24, 2012: Small
Ruud Veldhuizen, Fred Possmayer
Pulmonary surfactant is a mixture of lipids, mostly phospholipids, and proteins that allows for breathing with minimal effort. The current chapter discusses the metabolism of the phospholipids of this material. Surfactant phospholipids are synthesized in the type II epithelial cells of the lung. The lipids and surfactant proteins are assembled in intracellular storage organelles, called lamellar bodies, and are subsequently secreted into the alveolar space. Within this extracellular space surfactant undergoes several transformations...
2004: Sub-cellular Biochemistry
D Popov, M Simionescu
Since hyperglycaemia is known to affect normal pulmonary physiology and biochemistry and few structure-function correlations have been reported, we designed experiments on hamsters subjected to streptozotocin-induced diabetes or diabetes associated with hyperlipidaemia, and investigated the impact of these conditions on the lung structure. At time intervals ranging 2-24 weeks from the inception of disease (without correcting blood glucose with insulin), the animals were sacrificed, and plasma glucose and cholesterol assayed...
August 1997: European Respiratory Journal: Official Journal of the European Society for Clinical Respiratory Physiology
B Singh, L A Bate
BACKGROUND: Microwave (MW) radiation is being increasingly used as a source of heat supplementation during early postnatal development of pigs. Although MW radiation does not cause deleterious physiological effects, no specific information exists regarding its impact on immune cells such as macrophages. Pulmonary intravascular macrophages (PIMs) are emerging as important inflammatory cells due to their endocytic and secretory potential. An in vivo study was conducted to evaluate the effects of infrared, and low and high power MW radiation on the PIMs of pigs...
November 1996: Anatomical Record
H Mardassi, R Athanassious, S Mounir, S Dea
Cytolytic and noncytolytic strains of the porcine reproductive and respiratory syndrome virus (PRRSV) were isolated in primary cultures of porcine alveolar macrophages (PAM) from lung homogenates of stillborn fetuses or blood samples of dyspneic piglets collected from Quebec pig farms having experienced acute or chronic outbreaks of PRRS. Serological identification of the virus was confirmed by indirect immunofluorescence and indirect protein A-gold immunoelectron microscopy using reference antiserum prepared from experimentally-infected specific pathogen free (SPF) piglets and monoclonal antibodies (MoAbs) directed against the p15 nucleocapsid (N) protein of the reference ATCC-VR2332 isolate...
January 1994: Canadian Journal of Veterinary Research, Revue Canadienne de Recherche Vétérinaire
J M Besterman, J A Airhart, R C Woodworth, R B Low
The uptake and fate of pinocytosed fluid were investigated in monolayers of pulmonary alveolar macrophages and fetal lung fibroblasts using the fluid-phase marker, [14C]sucrose. Initial experiments revealed that cellular accumulation of chromatographically repurified [14C]sucrose was not linear with incubation time. Deviation from linearity was shown to be due to constant exocytosis of accumulating marker. Chromatographic analysis revealed that the cells were unable to metabolize sucrose and were releasing it intact by a process that was temperature-sensitive but not dependent on extracellular calcium and magnesium...
December 1981: Journal of Cell Biology
S Diment, P Stahl
Rabbit alveolar macrophages rapidly internalize and degrade mannosylated bovine serum albumin (125I-mannose-BSA). Trichloroacetic acid-soluble degradation products appear in the cells as early as 6 min after uptake at 37 degrees C, and in the extracellular medium after 10 min. Incubation of endocytic vesicles containing this ligand in isotonic buffers at pH 7.4 + ATP resulted in intravesicular proteolysis, which was inhibited by monensin, nigericin, or ammonium chloride. At pH 5.0, degradation proceeded rapidly and was abolished by lysis of the vesicles with 0...
December 5, 1985: Journal of Biological Chemistry
G E Quinonez, G T Simon, J M Kay
We have investigated two cases of chronic eosinophilic pneumonia using the electron microscope. The alveolar septa were thickened due to edema and an infiltrate of numerous mononuclear cells and eosinophils, with a few lymphocytes and occasional plasma cells. Macrophages were often located close to eosinophils and extracellular eosinophilic granules. Occasional eosinophilic granules were observed in the cytoplasm of mononuclear cells. The most striking finding was the presence of distinctive elongated, narrow, tubular inclusions in the cytoplasm of several of the mononuclear cells...
November 1986: Clinical and Investigative Medicine. Médecine Clinique et Experimentale
J Kaplan, D M Ward, H S Wiley
Rabbit alveolar macrophages which were treated at 0 degrees C with phenylarsine oxide and then incubated at 37 degrees C for 10 min exhibited a two- to threefold increase in surface receptor activity for macroglobulin.protease complexes, diferric transferrin, and mannose-terminal glycoproteins. Analysis of the concentration-dependence of ligand binding indicated that changes in ligand-binding activity were due to changes in receptor number rather than alterations in ligand-receptor affinity. Surface receptor number could also be increased by treatment of cells with three other sulfhydryl reagents, N-ethylmaleimide, p-chloromercurobenzoate, and iodoacetic acid...
July 1985: Journal of Cell Biology
J Kaplan, D M Ward
The ability of alveolar macrophages to remove potentially injurious agents is essential for normal lung function. One mechanism by which macrophages affect this function is by the internalization and clearance of noxious agents from lung fluid. Extracellular macromolecules may be removed as a result of nonspecific uptake via fluid-phase pinocytosis or as a result of binding to surface receptors followed by a highly efficient internalization of the receptor-ligand complex. The ability of macrophages to bind, internalize, and thus sequester extracellular macromolecules is facilitated by the fact that membrane components involved in this process may be reutilized...
June 1990: American Journal of Physiology
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