The airway epithelium serves as the interface between the host and external environment. In many chronic lung diseases, the airway is the site of substantial remodeling after injury. While, idiopathic pulmonary fibrosis (IPF) has traditionally been considered a disease of the alveolus and lung matrix, the dominant environmental (cigarette smoking) and genetic (gain of function
By definition of multicellularity, all animals need to keep their cells attached and intact, despite internal and external forces. Cohesion between epithelial cells provides this key feature. To better understand fundamental limits of this cohesion, we study the epithelium mechanics of an ultrathin (∼25 μm) primitive marine animal
- NSF-PAR ID:
- 10077151
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 115
- Issue:
- 44
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. E10333-E10341
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract MUC5B promoter variant) risk factor primarily affect the distal airway epithelium. Moreover, airway-specific pathogenic features of IPF include bronchiolization of the distal airspace with abnormal airway cell-types and honeycomb cystic terminal airway-like structures with concurrent loss of terminal bronchioles in regions of minimal fibrosis. However, the pathogenic role of the airway epithelium in IPF is unknown. Combining biophysical, genetic, and signaling analyses of primary airway epithelial cells, we demonstrate that healthy and IPF airway epithelia are biophysically distinct, identifying pathologic activation of the ERBB-YAP axis as a specific and modifiable driver of prolongation of the unjammed-to-jammed transition in IPF epithelia. Furthermore, we demonstrate that this biophysical state and signaling axis correlates with epithelial-driven activation of the underlying mesenchyme. Our data illustrate the active mechanisms regulating airway epithelial-driven fibrosis and identify targets to modulate disease progression. -
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Abstract Human intestinal enteroids derived from adult stem cells offer a relevant ex vivo system to study biological processes of the human gut. They recreate cellular and functional features of the intestinal epithelium of the small intestine (enteroids) or colon (colonoids) albeit limited by the lack of associated cell types that help maintain tissue homeostasis and respond to external challenges. In the gut, innate immune cells interact with the epithelium, support barrier function, and deploy effector functions. We have established a co‐culture system of enteroid/colonoid monolayers and underlying macrophages and polymorphonuclear neutrophils to recapitulate the cellular framework of the human intestinal epithelial niche. Enteroids are generated from biopsies or resected tissue from any segment of the human gut and maintained in long‐term cultures as three‐dimensional structures through supplementation of stem cell growth factors. Immune cells are isolated from fresh human whole blood or frozen peripheral blood mononuclear cells (PBMC). Monocytes from PBMC are differentiated into macrophages by cytokine stimulation prior to co‐culture. The methods are divided into the two main components of the model: (1) generating enteroid/colonoid monolayers and isolating immune cells and (2) assembly of enteroid/colonoid‐immune cell co‐cultures with separate apical and basolateral compartments. Co‐cultures containing macrophages can be maintained for 48 hr while those involving neutrophils, due to their shorter life span, remain viable for 4 hr. Enteroid‐immune co‐cultures enable multiple outcome measures, including transepithelial resistance, production of cytokines/chemokines, phenotypic analysis of immune cells, tissue immunofluorescence imaging, protein or mRNA expression, antigen or microbe uptake, and other cellular functions. © 2020 Wiley Periodicals LLC.
Basic Protocol 1 : Seeding enteroid fragments onto Transwells for monolayer formationAlternate Protocol : Seeding enteroid fragments for monolayer formation using triturationBasic Protocol 2 : Isolation of monocytes and derivation of immune cells from human peripheral bloodBasic Protocol 3 : Isolation of neutrophils from human peripheral bloodBasic Protocol 4 : Assembly of enteroid/macrophage or enteroid/neutrophil co‐culture -
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Background Interleukin 13 (IL‐13) is a pleiotropic cytokine that has been shown to be important in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) and other type 2 inflammation–related diseases. Increased IL‐13 expression can elicit several pro‐inflammatory effects, including eosinophilia, and pathology such as increased mucus secretion. Polypogenesis in chronic rhinosinusitis (CRS) can be caused by hypoxia, which can also lead to hyperpermeability of airway epithelium and epithelium‐to‐mesenchymal translation through the upregulation of hypoxia‐associated genes, such as HIF1. Whether T‐helper 2 (Th2) inflammatory cytokines, such as IL‐13, can also induce sinonasal epithelial hypoxia‐associated genes is currently unknown.
Methods Human air‐liquid interface (ALI) sinonasal epithelial cell cultures treated with recombinant IL‐13 were analyzed by real‐time polymerase chain reaction (PCR) and flow cytometry to determine the effect on epithelial cells.
Results Whole tissue from CRSwNP subjects showed increased
HIF1A gene expression. Treatment of fully differentiated human ALI cultures with IL‐13 resulted in a concurrent increase inHIF1A andARNT messenger RNA (mRNA) expression. However, the level ofEPAS1 expression was significantly reduced. IL‐13 also had a dose‐dependent response on the expression of HIF genes and the time course experiment showed peak expression ofHIF1A andARNT at 5 to 7 days poststimulation. Remarkably, CD73 surface expression also peaked at day 5 poststimulation.Conclusion Our data suggests that IL‐13 can induce hypoxia signaling pathway genes leading to surface expression of CD73, which has an anti‐inflammatory effect.
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Abstract Background Collective cell migration underlies many essential processes, including sculpting organs during embryogenesis, wound healing in the adult, and metastasis of cancer cells. At mid-oogenesis,
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Conclusions Overall, our results identified differentially and temporally expressed genetic networks that may facilitate the efficient development and migration of border cells. The genes identified here represent a wealth of new candidates to investigate the molecular nature of dynamic collective cell migrations in developing tissues.
