Search results for "Macrophages."
showing 10 items of 530 documents
Pharmacology of Ischemia-Reperfusion. Translational Research Considerations.
2016
Ischemia-reperfusion (IRI) is a complex physiopathological mechanism involving a large number of metabolic processes that can eventually lead to cell apoptosis and ultimately tissue necrosis. Treatment approaches intended to reduce or palliate the effects of IRI are varied, and are aimed basically at: inhibiting cell apoptosis and the complement system in the inflammatory process deriving from IRI, modulating calcium levels, maintaining mitochondrial membrane integrity, reducing the oxidative effects of IRI and levels of inflammatory cytokines, or minimizing the action of macrophages, neutrophils, and other cell types. This study involved an extensive, up-to-date review of the bibliography …
Inhibition of 5-lipoxygenase activity by the natural anti-inflammatory compound aethiopinone
2001
Objetive and Design: We have investigated the mechanisms of action of aethiopinone, an anti-inflammatory compound from Salvia aethiopis L. roots.¶Material and Subjects: Human neutrophils from healthy volunteers and murine peritoneal macrophages. Swiss mice were randomly divided into groups of six animals.¶Treatment: Test compounds were applied topically in the mouse ear oedema test. In the air pouch, mice received aethiopinone (0.001-0.5 μmol/pouch or 12.5-50 mg/kg p.o.).¶Methods: LTB4 production was assayed in human neutrophils and COX-2 and iNOS activities in murine macrophages. Air pouches were induced subcutaneously in mice and injected with zymosan on the day six. Mouse ear oedema was …
Electrochemical sensor based on rGO/Au nanoparticles for monitoring H2O2 released by human macrophages
2021
Abstract Increased oxidative burden contributes to the pathogenesis of most inflammatory diseases and is associated with aging and chronic inflammation. Macrophages contribute to the generation of reactive oxygen species (ROS) within inflamed tissues. Currently, ROS generation is measured using fluorescent probes and colorimetric/fluorimetric biochemical assays. Hydrogen peroxide (H2O2) diffuses through the cell membrane and can be monitored in the extracellular space. Herein, we present a sensor for H2O2 detection released by cells in culture supernatants. H2O2 sensing performance was evaluated using chronoamperometric detection. A sensitivity of 0.0641 μA μM−1 cm−2 with a limit of detecti…
Dysidotronic acid, a new sesquiterpenoid, inhibits cytokine production and the expression of nitric oxide synthase.
2001
In a previous study, we reported a new bioactive sesquiterpenoid, named dysidotronic acid, to be a potent, selective human synovial phospholipase A(2) inhibitor. Dysidotronic acid is a novel, non-complex manoalide analogue lacking the pyranofuranone ring. We now investigate the effect of this compound on cytokine, nitric oxide and prostanoid generation on the mouse macrophage cell line RAW 264.7, where it showed a dose-dependent inhibition with inhibitory concentration 50% values in the micromolar range. This effect was also confirmed in the mouse air pouch injected with zymosan. Dysidotronic acid inhibited the production of tumor necrosis factor alpha and interleukin-1 beta as well as the …
Freeze-fracture features of epithelioid cells, multinucleated giant cells, and phagocytic macrophages
1987
The freeze-fracture morphology of epithelioid cells, multinucleated giant cells (Langhans' type), and phagocytic macrophages was investigated. The intensely folded and interdigitating surface membranes of epithelioid cells and multinucleated giant cells displayed no specialized areas of cell contact. The size of the intramembranous particles (IMP) and the fact that the area density of IMPs was higher in the cytoplasmic (P) faces than in the external (E) faces of the cell membranes agreed with observations in other eukaryotic cells. The area densities of the IMPs suggest lower transport rates of molecules across the cell membranes of granuloma cells than of certain epithelial cells. Small pi…
Polymeric Selectin Ligands Mimicking Complex Carbohydrates: From Selectin Binders to Modifiers of Macrophage Migration
2016
Novel polymeric cell adhesion inhibitors were developed in which the selectin tetrasaccharide sialyl-LewisX (SLeX ) is multivalently presented on a biocompatible poly(2-hydroxypropyl)methacrylamide (PHPMA) backbone either alone (P1) or in combination with O-sulfated tyramine side chains (P2). For comparison, corresponding polymeric glycomimetics were prepared in which the crucial "single carbohydrate" substructures fucose, galactose, and sialic acid side chains were randomly linked to the PHPMA backbone (P3 or P4 (O-sulfated tyramine)). All polymers have an identical degree of polymerization, as they are derived from the same precursor polymer. Binding assays to selectins, to activated endo…
Immunophenotype based on inflammatory cells, PD-1/PD-L1 signalling pathway and M2 macrophages predicts survival in gastric cancer
2020
Abstract Background Immune response against cancer has prognostic impact but its role in gastric cancer is poorly known. The aim of the study was to assess the prognostic significance of immune cell score (CD3+, CD8+), tumour immune escape (PD-L1, PD-1) and immune tolerance (Clever-1). Methods After exclusion of Epstein-Barr virus positive (n = 4) and microsatellite instable (n = 6) tumours, the study included 122 patients with GC undergoing D2 gastrectomy. CD3+ and CD8+ based ICS, PD-L1, PD-1 and Clever-1 expressions were evaluated. Differences in survival were examined using Cox regression adjusted for confounders. The primary outcome was 5-year survival. Results The 5-year overall surviv…
Immune cells in colorectal cancer: prognostic relevance and therapeutic strategies.
2008
During the last two decades, considerable efforts have been made to improve the prevention, early diagnosis and therapy of colorectal cancer by gaining enhanced insights into disease-specific pathogenesis. Along these lines, tumor-infiltrating immune cells turned out to be critical indicators for an efficient antitumor immune response and the number and type of tumor-infiltrating immune cells determined the resulting tumor prognosis. This review aims to describe the prognostic relevance of the different subsets of tumor-infiltrating immune cells and highlights their specific function in the complex process of immune system-mediated rejection of colorectal cancer cells. Considering the clini…
Gliadin activates arginase pathway in RAW264.7 cells and in human monocytes
2014
AbstractCeliac disease (CD) is an autoimmune enteropathy triggered in susceptible individuals by the ingestion of gliadin-containing grains. Recent studies have demonstrated that macrophages play a key role in the pathogenesis of CD through the release of inflammatory mediators such as cytokines and nitric oxide (NO). Since arginine is the obliged substrate of iNOS (inducible nitric oxide synthase), the enzyme that produces large amount of NO, the aim of this work is to investigate arginine metabolic pathways in RAW264.7 murine macrophages after treatment with PT-gliadin (PTG) in the absence and in the presence of IFNγ. Our results demonstrate that, besides strengthening the IFNγ-dependent …
Augmented antigen presentation by mouse Ia + T clone cells BK-BI-2.6.O4.1 mediated by transferrin receptors.
1996
The murine T clone cells BK-BI-2.6.O4.1 (BI/O4.1) synthesize and express MHC class II molecules constitutively. BI/O4.1 cells are able to present various protein antigens to antigen-specific CD4 + T cells. However, a 10-fold higher concentration of antigen is needed to activate specific T cells to lymphokine secretion by BI/O4.1 cells in comparison with spleen cells or with the more homogeneous population of bone marrow-derived macrophages (BMMph). The authors tested whether the reduced antigen presentation potential of BI/O4.1 cells was augmented by transferrin-mediated uptake of the model antigen ovalbumin (OVA) coupled to human ferric transferrin. It was shown that 240-fold less OVA was …