Search results for "Macrophage"
showing 10 items of 781 documents
Biological properties of extracellular vesicles and their physiological functions
2015
The authors wish to thank Dr R Simpson and Dr D Taylor for critical reading of the manuscript and acknowledge the Horizon 2020 European Cooperation in Science and Technology programme and its support of our European Network on Microvesicles and Exosomes in Health & Disease (ME-HaD; BM1202 www.cost.eu/COST_Actions/bmbs/Actions/BM1202). In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological functions of both recipient and parent cells. While intensive invest…
Human apolipoprotein A-I natural variants: molecular mechanisms underlying amyloidogenic propensity
2012
Human apolipoprotein A-I (apoA-I)-derived amyloidosis can present with either wild-type (Wt) protein deposits in atherosclerotic plaques or as a hereditary form in which apoA-I variants deposit causing multiple organ failure. More than 15 single amino acid replacement amyloidogenic apoA-I variants have been described, but the molecular mechanisms involved in amyloid-associated pathology remain largely unknown. Here, we have investigated by fluorescence and biochemical approaches the stabilities and propensities to aggregate of two disease-associated apoA-I variants, apoA-IGly26Arg, associated with polyneuropathy and kidney dysfunction, and apoA-ILys107-0, implicated in amyloidosis in severe…
Production of reactive oxygen intermediates by human macrophages exposed to soot particles and asbestos fibers and increase in NF-kappa B p50/p105 mR…
1999
Alveolar macrophages (AM) play a decisive role in the immunologic defense system of the lung and in inflammatory pulmonary pathomechanisms. AM and blood monocytes (BM) were exposed to chrysotile B, soot FR 101, and Printex 90 (P 90). We evaluated the reactive oxygen intermediate (ROI) release of AM and BM after particle exposure. ROI release was measured by chemiluminescence. Thirty-minute exposure caused a significant (up to 2.5-fold) increase in ROI release of AM (100 micrograms/10(6) cells) compared with control experiments (p0.01). Identical exposure conditions for BM resulted in a similar reaction pattern (maximum 2.2-fold increase in ROI release; p0.05). After a 90-min particle exposu…
Effect of cilomilast (Ariflo) on TNF-α, IL-8, and GM-CSF release by airway cells of patients with COPD
2003
Background: Inflammation in chronic obstructive pulmonary disease (COPD) is characterised by increased neutrophilic infiltration of the airways. Cilomilast, a novel selective phosphodiesterase 4 inhibitor in clinical development for COPD treatment, exerts anti-inflammatory effects. The ability of cilomilast to inhibit the release of neutrophil chemoattractants such as tumour necrosis factor (TNF)-α, interleukin (IL)-8, and granulocyte-macrophage colony stimulating factor (GM-CSF) by bronchial epithelial cells and sputum cells isolated from 10 patients with COPD, 14 normal controls, and 10 smokers was investigated. Methods: Bronchial epithelial cells obtained by bronchial brushing and sputum…
Oxidative Stress and Respiratory System: Pharmacological and Clinical Reappraisal of N-Acetylcysteine
2014
Abstract The large surface area for gas exchange makes the respiratory system particularly susceptible to oxidative stress-mediated injury. Both endogenous and exogenous pro-oxidants (e.g. cigarette smoke) trigger activation of leukocytes and host defenses. These mechanisms interact in a ìmultilevel cycleî responsible for the control of the oxidant/antioxidant homeostasis. Several studies have demonstrated the presence of increased oxidative stress and decreased antioxidants (e.g. reduced glutathione [GSH]) in subjects with chronic obstructive pulmonary disease (COPD), but the contribution of oxidative stress to the pathophysiology of COPD is generally only minimally discussed. The aim of t…
Indoor air pollutants stimulate interleukin-8-specific mRNA expression and protein secretion of alveolar macrophages.
1998
Indoor air pollutants may cause inflammatory changes of the airways and adjacent pulmonary tissue. After phagocytosis of inhaled particles alveolar macrophages (AM) release chemotactic mediators capable of attracting inflammatory cells into the lung tissue. To evaluate these mechanisms further peripheral blood mononuclear cells (PBMNC) and human AM (freshly recovered from the lower respiratory tract) were exposed to the indoor particles Soot FR 101 and Printex 90, the asbestos fiber Chrysotile B, and titanium dioxide (TiO2) at concentrations of 10 or 50 microg/10(6) cells for up to 8 h. The migration of granulocytes into the conditioned supernatants of AM and PBMNC was quantified by chemota…
Lung-restricted activation of the alveolar macrophage/monocyte system in pulmonary sarcoidosis.
1992
An activation of T-cells that is restricted to the lung has been demonstrated in pulmonary sarcoidosis. The role of blood monocytes (MO) and alveolar macrophages (AM) in this concept of compartmentalized inflammation has not yet been evaluated. In order to elucidate this question, we measured the release of tumor necrosis factor alpha (TNF alpha) and interleukin-1 (IL-1) by peripheral blood mononuclear cells (PBMNC) and AM in 43 patients with sarcoidosis (32 with active, 11 with inactive disease) without therapy and correlated the spontaneous monokine release to parameters of the T-cell alveolitis and the course of the disease. TNF alpha as well as IL-1 were spontaneously released by AM of …
Theophylline suppresses the release of tumour necrosis factor-alpha by blood monocytes and alveolar macrophages.
1994
The purpose of this study was to evaluate the effect of theophylline on tumour necrosis factor-alpha (TNF-alpha) release by human blood monocytes (BMo), and rat BMo and alveolar macrophages (AM). BMo and AM were incubated in the absence or presence of theophylline, and the cell-free supernatants were harvested and tested for TNF-alpha activity by bioassay. Theophylline dose-dependently reduced TNF-alpha release by human BMo: significant inhibition was observed at 100 microns (41 +/- 5.9% of controls) and at 50 microns (59 +/- 4.8% of controls), while the inhibitory activity of theophylline at 10 microns (71 +/- 8.9% of controls) was not statistically significant. This activity was maximal a…
Chronic obstructive pulmonary disease and neutrophil infiltration: role of cigarette smoke and cyclooxygenase products.
2010
Cigarette smoke is the main cause of chronic obstructive pulmonary disease (COPD), where it can contribute to the observed airway inflammation. PGE(2) is produced within human airways, and both pro- and anti-inflammatory activities have been reported. We quantitated PGE(2) concentrations in induced sputum supernatants from different groups of subjects and correlated the obtained values to neutrophil infiltration as well as to the expression of cyclooxygenase-2 (COX-2). Cigarette smoke extract (CSE) was used to evaluate the effect of smoking on COX-2 and PGE(2) receptor expression as well as on PGE(2) release in neutrophils and alveolar macrophages (AM) obtained from normal donors. The effec…
An open-label, prospective phase I/II study evaluating the immunogenicity and safety of a ras peptide vaccine plus GM-CSF in patients with non-small …
2007
Mutations of the ras gene have been reported in 20-40% of NSCLC patients. If present, they are critical for the malignant phenotype of these tumors. Therefore, targeting them by specific vaccination is a promising therapeutic approach. In a clinical trial we screened for ras mutations in patients with NSCLC. Patients with ras-positive tumors were immunized six times intradermally with a mixture of seven peptides representing the most common ras mutations. Objectives of the study were the feasibility, efficacy and safety of the vaccination. In addition, the induction of a specific immune reaction was investigated by DTH tests, and the induction of peptide-specific T cells was tested in ex vi…