Search results for "phage"

Epithelium‐specific MyD88 signaling, but not DCs or macrophages, control acute intestinal infection with Clostridium difficile

2019

Infection with Clostridium difficile is one of the major causes of health care acquired diarrhea and colitis. Signaling though MyD88 downstream of TLRs is critical for initiating the early protective host response in mouse models of C. difficile infection (CDI). In the intestine, MyD88 is expressed in various tissues and cell types, such as the intestinal epithelium and mononuclear phagocytes (MNP), including DC or macrophages. Using a genetic gain-of-function system, we demonstrate here that restricting functional MyD88 signaling to the intestinal epithelium, but also to MNPs is sufficient to protect mice during acute CDI by upregulation of the intestinal barrier function and recruitment o…

The activation of Wnt signaling by a STAT6-dependent macrophage phenotype promotes mucosal repair in murine IBD

2016

The complete repair of the mucosa constitutes a key goal in inflammatory bowel disease (IBD) treatment. The Wnt signaling pathway mediates mucosal repair and M2 macrophages that coordinate efficient healing have been related to Wnt ligand expression. Signal transducer and activator of transcription 6 (STAT6) mediates M2 polarization in vitro and we hypothesize that a STAT6-dependent macrophage phenotype mediates mucosal repair in acute murine colitis by activating the Wnt signaling pathway. Our results reveal an impaired mucosal expression of M2 macrophage-associated genes and delayed wound healing in STAT6(-/-) mice treated with 2,4,6-trinitrobenzenesulfonic acid (TNBS). These mice also ex…

Overview of General and Discriminating Markers of Differential Microglia Phenotypes.

2020

Inflammatory processes and microglia activation accompany most of the pathophysiological diseases in the central nervous system. It is proven that glial pathology precedes and even drives the development of multiple neurodegenerative conditions. A growing number of studies point out the importance of microglia in brain development as well as in physiological functioning. These resident brain immune cells are divergent from the peripherally infiltrated macrophages, but their precise in situ discrimination is surprisingly difficult. Microglial heterogeneity in the brain is especially visible in their morphology and cell density in particular brain structures but also in the expression of cell…

NFATc1 releases BCL6-dependent repression of CCR2 agonist expression in peritoneal macrophages fromSaccharomyces cerevisiaeinfected mice

2016

The link between the extensive usage of calcineurin (CN) inhibitors cyclosporin A and tacrolimus (FK506) in transplantation medicine and the increasing rate of opportunistic infections within this segment of patients is alarming. Currently, how peritoneal infections are favored by these drugs, which impair the activity of several signaling pathways including the Ca(++) /CN/NFAT, Ca(++) /CN/cofilin, Ca(++) /CN/BAD, and NF-κB networks, is unknown. Here, we show that Saccharomyces cerevisiae infection of peritoneal resident macrophages triggers the transient nuclear translocation of NFATc1β isoforms, resulting in a coordinated, CN-dependent induction of the Ccl2, Ccl7, and Ccl12 genes, all enc…

2018

Abstract Chronic hepatitis leads to liver fibrosis and cirrhosis. Cirrhosis is a major cause of worldwide morbidity and mortality. Macrophages play a key role in fibrosis progression and reversal. However, the signals that determine fibrogenic vs fibrolytic macrophage function remain ill defined. We studied the role of interleukin-4 receptor α (IL-4Rα), a potential central switch of macrophage polarization, in liver fibrosis progression and reversal. We demonstrate that inflammatory monocyte infiltration and liver fibrogenesis were suppressed in general IL-4Rα−/− as well as in macrophage-specific IL-4Rα−/− (IL-4RαΔLysM) mice. However, with deletion of IL-4RαΔLysM spontaneous fibrosis revers…

Hyperosmolarity and Benzalkonium Chloride Differently Stimulate Inflammatory Markers in Conjunctiva-Derived Epithelial Cells in vitro

2017

Tear hyperosmolarity is known to cause ocular surface inflammation in dry eye syndrome. Benzalkonium chloride (BAK), an eyedrop preservative, is known to induce dry eye in long-term-treated patients. Analyzing the modulation of the proinflammatory potential of hyperosmolarity in the presence of BAK on the conjunctiva could give new insights into the effect of this preservative on the disease. In a hyperosmolar model on a conjunctiva-derived cell line, and in the presence of BAK, we evaluated key inflammatory markers [CCL2, IL-8, IL-6, macrophage migration inhibitory factor (MIF) and intercellular adhesion molecule (ICAM)-1] as well as the osmoprotectant element nuclear factor of activated T…

Exosome secretion by Leishmania infantum modulate the chemotactic behavior and cytokinic expression creating an environment permissive for early infe…

2019

Abstract In recent years, several studies demonstrated the role of exosomes in intercellular communications, several Leishmania species belonging to subgenera Leishmania and Viannia have been demonstrated to release exosomes, and their role in parasite-macrophage interactions and in leishmaniasis development has been investigated. However, the release of exosomes by Leishmania infantum has not been studied so far. The aim of this study was to isolate and characterize L. infantum exosomes, and to investigate the biological activity of these exosomes in macrophage cultures. To this end, exosomes were collected from both amastigote and promastigote L. infantum conditioned medium by ultracentri…

Ruegeria denitrificans sp. nov., a marine bacterium in the family Rhodobacteraceae with the potential ability for cyanophycin synthesis.

2018

Strain CECT 5091T, an aerobic, marine, Gram-reaction- and Gram-stain-negative, chemoheterotrophic bacterium was isolated from oysters harvested off the Spanish Mediterranean coast. Analysis of the 16S rRNA gene sequence placed the strain within the genus Ruegeria , in the family Rhodobacteraceae , with 16S rRNA gene similarities of 98.7, 98.7 and 98.4 % to Ruegeria conchae , Ruegeria atlantica and Ruegeria arenilitoris , respectively. Average nucleotide identities (ANI) and in silico DNA–DNA hybridization (DDH) were determined, comparing the genome sequence of CECT 5091T with those of the type strains of 12 species of the genus Ruegeria : the values obtained were always below the thresholds…

From Ecology to Biotechnology, Study of the Defense Strategies of Algae and Halophytes (from Trapani Saltworks, NW Sicily) with a Focus on Antioxidan…

2019

This study aimed at the characterization of the antioxidant power of polyphenol extracts (PE) obtained from the algae Cystoseira foeniculacea (CYS) (Phaeophyta) and from the halophyte Halocnemum strobilaceum (HAL), growing in the solar saltworks of western Sicily (Italy), and at the evaluation of their anti-microfouling properties, in order to correlate these activities to defense strategies in extreme environmental conditions. The antioxidant properties were assessed in the PE based on the total antioxidant activity test and the reducing power test

Novel Microglia Depletion Systems: A Genetic Approach Utilizing Conditional Diphtheria Toxin Receptor Expression and a Pharmacological Model Based on…

2019

Microglia are the main population of macrophage residing in the central nervous system (CNS). Depletion experiments gave important insights into the physiology and function of microglia in healthy and diseased CNS. Ablation of microglia can be achieved by application of pharmacological or genetic tools. Here, we describe two approaches to ablate microglia: an efficient genetic model that utilizes DTRMG mouse line that has diphtheria toxin receptor (DTR) expression regulated by the promoter activity of the fractalkine receptor (CX3CR1) gene, and a pharmacological model that utilizes the blocking of macrophage colony-stimulating factor 1 receptor (CSF-1R) with a blocking antibody. Both the ad…