Respiratory epithelium

About: Respiratory epithelium is a research topic. Over the lifetime, 5048 publications have been published within this topic receiving 222304 citations. The topic is also known as: respiratory tract epithelium & Respiratory Mucosa.

Niflumic acid suppresses interleukin-13-induced asthma phenotypes.

Abstract: Rationale: Chloride channels have been implicated in the regulation of mucus production in epithelial cells. Expression of hCLCA1, a calcium-activated chloride channel, has been reported to be increased in the airway epithelium of patients with asthma. Interleukin (IL)-13 induces the cardinal features of bronchial asthma, and glucocorticoids are not sufficient to suppress IL-13–induced airway hyperresponsiveness or goblet cell hyperplasia.Objectives: We studied the effects of chloride channel inhibitors in IL-13–induced asthma.Methods: The effects of niflumic acid (NA), a relatively specific blocker of calcium-activated chloride channel (CLCA), on goblet cell hyperplasia, eosinophil accumulation, and airway hyperresponsiveness were evaluated after IL-13 instillation into the airways. Because IL-13–dependent features rely on JAK/STAT6 signaling, the effect of NA on phosphorylation of JAK2 and STAT6 after IL-13 stimulation was examined in airway epithelial cells in vitro. The expression of the mCLCA family ...

Epithelial cell-extracellular matrix interactions and stem cells in airway epithelial regeneration.

Abstract: In healthy subjects, the respiratory epithelium forms a continuous lining to the airways and to the environment, and plays a unique role as a barrier against external deleterious agents to protect the airways from the insults. In respiratory diseases such as cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD), chronic bronchitis, or asthma, the airway epithelium is frequently remodeled and injured, leading to the impairment of its defense functions. The rapid restoration of the epithelial barrier is crucial for these patients. The complete regeneration of the airway epithelium is a complex phenomenon, including not only the epithelial wound repair but also the epithelial differentiation to reconstitute a fully well differentiated and functional epithelium. The regeneration implies two partners: the epithelial stem/progenitor cells and factors able to regulate this process. Among these factors, epithelial cells-extracellular matrix (ECM) interactions play a crucial role. The secretion of a provisional ECM, the cell-ECM relationships through epithelial receptors, and the remodeling of the ECM by proteases (mainly matrix metalloproteinases) contribute not only to airway epithelial repair by modulating epithelial cell migration and proliferation, but also to the differentiation of repairing cells leading to the complete restoration of the wounded epithelium. A better characterization of resident stem cells and of effectors of the regeneration process is an essential prerequisite to propose new regenerative therapeutics to patients suffering from infectious/inflammatory respiratory diseases.

Ultrastructural characterization of the nasal respiratory epithelium in the rat

Abstract: This ultrastructural study of the respiratory epithelium of the rat nasal mucosa revealed six morphologically distinct cell types: goblet cells, basal cells, ciliated cells, nonciliated columnar cells, cuboidal cells, and brush cells. The latter three have not been previously characterized in the rat nasal mucosa by transmission electron microscopy. Cuboidal cells observed on the conchae and lateral wall had short apical microvilli which were less dense than the microvilli of the nonciliated columnar cells. Nonciliated columnar cells also identified on the conchae and lateral wall had short microvilli and an extensive network of smooth endoplasmic reticulum in the apical region. The brush cell had distinct ultrastructural features; it was pear-shaped, with the broad base adjacent to the basement membrane and large microvilli on the surface. Microfilaments, microtubules, vesicles, and paired cisternae were found in the apical cytoplasm. Brush cells occurred singly on the conchae and lateral wall but were not identified in the respiratory epithelium of the nasal septum. These findings indicate the complexity of cell types composing the rat nasal respiratory epithelium.

GRHL2 coordinates regeneration of a polarized mucociliary epithelium from basal stem cells

Abstract: Pseudostratified airway epithelium of the lung is composed of polarized ciliated and secretory cells maintained by basal stem/progenitor cells. An important question is how lineage choice and differentiation are coordinated with apical-basal polarity and epithelial morphogenesis. Our previous studies indicated a key integrative role for the transcription factor Grainyhead-like 2 (Grhl2). In this study, we present further evidence for this model using conditional gene deletion during the regeneration of airway epithelium and clonal organoid culture. We also use CRISPR/Cas9 genome editing in primary human basal cells differentiating into organoids and mucociliary epithelium in vitro. Loss of Grhl2 inhibits organoid morphogenesis and the differentiation of ciliated cells and reduces the expression of both notch and ciliogenesis genes (Mcidas, Rfx2, and Myb) with distinct Grhl2 regulatory sites. The genome editing of other putative target genes reveals roles for zinc finger transcription factor Znf750 and small membrane adhesion glycoprotein in promoting ciliogenesis and barrier function as part of a network of genes coordinately regulated by Grhl2.