Search results for "Epithelial cell"
showing 10 items of 475 documents
Interferon-λ and interleukin 22 act synergistically for the induction of interferon-stimulated genes and control of rotavirus infection.
2015
The epithelium is the main entry point for many viruses, but the processes that protect barrier surfaces against viral infections are incompletely understood. Here we identified interleukin 22 (IL-22) produced by innate lymphoid cell group 3 (ILC3) as an amplifier of signaling via interferon-λ (IFN-λ), a synergism needed to curtail the replication of rotavirus, the leading cause of childhood gastroenteritis. Cooperation between the receptor for IL-22 and the receptor for IFN-λ, both of which were 'preferentially' expressed by intestinal epithelial cells (IECs), was required for optimal activation of the transcription factor STAT1 and expression of interferon-stimulated genes (ISGs). These d…
Protective effects of melatonin in inflamed intestinal epithelium are associated with reduced NF-κB activation and changes in DNA methylation status
2018
Melatonin is the main product of the pineal gland but is also released in the gastrointestinal tract (GIT). Production of melatonin at GIT is independent of the photoperiod and contributes almost completely to plasma melatonin concentration during daylight hours. The physiological role of melatonin at GIT is poorly characterized but recently anti-inflammatory effects have been reported. In this study, we evaluated the effect of Melatonin in intestinal epithelial cells (IEC) stimulated by Interleukin-1β. Our results clearly show that melatonin at micromolar concentrations inhibits the inflammatory response in IEC. The protective effect is expressed through a marked decrease in release and ex…
Cellular and Molecular Signatures of Oxidative Stress in Bronchial Epithelial Cell Models Injured by Cigarette Smoke Extract
2022
Exposure of the airways epithelium to environmental insults, including cigarette smoke, results in increased oxidative stress due to unbalance between oxidants and antioxidants in favor of oxidants. Oxidative stress is a feature of inflammation and promotes the progression of chronic lung diseases, including Chronic Obstructive Pulmonary Disease (COPD). Increased oxidative stress leads to exhaustion of antioxidant defenses, alterations in autophagy/mitophagy and cell survival regulatory mechanisms, thus promoting cell senescence. All these events are amplified by the increase of inflammation driven by oxidative stress. Several models of bronchial epithelial cells are used to study the molec…
Improving extracellular vesicles visualization: From static to motion
2020
AbstractIn the last decade, extracellular vesicles (EVs) have become a hot topic. The findings on EVs content and effects have made them a major field of interest in cancer research. EVs, are able to be internalized through integrins expressed in parental cells, in a tissue specific manner, as a key step of cancer progression and pre-metastatic niche formation. However, this specificity might lead to new opportunities in cancer treatment by using EVs as devices for drug delivery. For future applications of EVs in cancer, improved protocols and methods for EVs isolation and visualization are required. Our group has put efforts on developing a protocol able to track the EVs for in vivo intern…
Interaction of antibodies to proteinase 3 (classic anti-neutrophil cytoplasmic antibody) with human renal tubular epithelial cells: impact on signali…
2002
Abstract Among the anti-neutrophil cytoplasmic Abs (ANCA), those targeting proteinase 3 (PR3) have a high sensitivity and specificity for Wegener’s granulomatosis (WG). A pathogenetic role for these autoantibodies has been proposed due to their capacity of activating neutrophils in vitro. Recently, PR3 was also detected in human renal tubular epithelial cells (TEC). In the present study, the effect of murine monoclonal anti-PR3 Abs (anti-PR3) and purified c-ANCA targeting PR3 from WG serum on isolated human renal tubular cell signaling and inflammatory mediator release was characterized. Priming of TEC with TNF-α resulted in surface expression of PR3, as quantified in immunofluorescence stu…
Niche-induced cell death and epithelial phagocytosis regulate hair follicle stem cell pool.
2015
Tissue homeostasis is achieved through a balance of cell production (growth) and elimination (regression). In contrast to tissue growth, the cells and molecular signals required for tissue regression remain unknown. To investigate physiological tissue regression, we use the mouse hair follicle, which cycles stereotypically between phases of growth and regression while maintaining a pool of stem cells to perpetuate tissue regeneration. Here we show by intravital microscopy in live mice that the regression phase eliminates the majority of the epithelial cells by two distinct mechanisms: terminal differentiation of suprabasal cells and a spatial gradient of apoptosis of basal cells. Furthermor…
Cigarette smoke affects the onco-suppressor DAB2IP expression in bronchial epithelial cells of COPD patients
2019
AbstractCigarette smoke is a risk factor for COPD and lung cancer. In cancer, epigenetic modifications affect the expression of Enhancer of Zester Homolog 2 (EZH2), and silenced disabled homolog 2 interacting protein gene (DAB2IP) (onco-suppressor gene) by Histone H3 tri-methylation in lysine 27 (H3K27me3). In“ex vivo”studies, we assessed EZH2, H3K27me3 and DAB2IP immunoreactivity in bronchial epithelial cells from COPD patients (smokers, ex-smokers), Smoker and control subjects. In“in vitro” experiments we studied the effect of cigarette smoke extract (CSE) on EZH2/H3K27me3/DAB2IP expression, apoptosis, invasiveness, and vimentin expression in 16HBE, primary cells, and lung cancer cell lin…
α-parvin is required for epidermal morphogenesis, hair follicle development and basal keratinocyte polarity
2020
Epidermal morphogenesis and hair follicle (HF) development depend on the ability of keratinocytes to adhere to the basement membrane (BM) and migrate along the extracellular matrix. Integrins are cell-matrix receptors that control keratinocyte adhesion and migration, and are recognized as major regulators of epidermal homeostasis. How integrins regulate the behavior of keratinocytes during epidermal morphogenesis remains insufficiently understood. Here, we show that alpha-parvin (alpha-pv), a focal adhesion protein that couples integrins to actin cytoskeleton, is indispensable for epidermal morphogenesis and HF development. Inactivation of the murine alpha-pv gene in basal keratinocytes res…
Tissue kallikrein and kininogen in human sweat glands and psoriatic skin
1991
The cellular localization of immunoreactive tissue kallikrein and kininogen was studied in normal and psoriatic human skin. Immunoreactivity to both enzyme and substrate was observed in secretory granules of the dark cells in the secretory fundus (acinus) of the sweat glands. Double immunostaining revealed a segmental distribution of the two antigens. Each acinar section contained either tissue kallikrein or kininogen. However, there appeared to be a junctional zone in which both were present, but in separate dark cells. Immunoreactivity for both antigens was also observed in close apposition to the luminal microvilli of the duct cells. No specific immunostaining was seen in sebaceous gland…
Analogies between atherosclerosis and age-related maculopathy: expected roles of oxysterols
2006
The pathogenesis of age-related macular degeneration (ARMD) is not clearly understood. Like other age-related diseases, it is associated with abnormal deposits called drusen. These drusens are localized in Bruch's membrane. Recent investigations have shown a link between drusen formation and inflammatory and immunologic reactions. The involvement of oxidative stress is supported by available data as an important contributing factor in the developement of ARMD. The data regarding the nature and the source of the deposits suggest that ARMD may share similar pathways with atherosclerosis. The role of oxydized products of cholesterol, the oxysterols, in the pathogenesis of atherosclerosis is we…