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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Cell Adhesion, Cell Communication, Cells, Cultured, Epithelial Cells, Humans, Intercellular Adhesion Molecule-1, Interleukin-8, Lung, Neutrophils.
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Do neutrophil adherence to lung epithelial cells induce interleukin-8 release? Context: Neutrophil recruitment to the lungs and transmigration through the pulmonary epithelium to reach the respiratory tract are characteristics of airway inflammation. Interleukin-8 (IL-8) plays a critical role in the recruitment of neutrophils to epithelial cells. We investigated the effect of neutrophil adherence to epithelial cells on cytokine secretion. The production of IL-8 from cultured A549 epithelial cells was assayed and neutrophil adherence assay in the presence or absence of interferon-gamma (IFN-gamma) plus tumor necrosis factor-alpha (TNF-alpha) plus interleukin-1 beta (IL-1 beta) stimulation was studied on cultured A549 epithelial cells. The role of an adhesion molecule in the modulation of neutrophil adherence was examined by pretreatment with intercellular adhesion molecule-1 (ICAM-1) blocking antibody. There was an increase in IL-8 release from epithelial cells that was time-dependent and in the magnitude of neutrophil adherence to the epithelial cells. Stimulation of epithelial cells with IFN-gamma +TNF-alpha +IL-1 beta significantly increased IL-8 release and neutrophil adherence. The spontaneous or IFN-gamma +TNF-alpha +IL-1 beta-induced IL-8 release was significantly augmented after the addition of neutrophils. The inhibition of neutrophil adherence to epithelial cells by ICAM-1 blocking antibody downregulated the augmented release of IL-8 with or without IFN-gamma +TNF-alpha +IL-1 beta stimulation. Placing a membrane filter on cultured epithelial cells to prevent neutrophil adherence significantly decreased IL-8 release from epithelial cells with IFN-gamma +TNF-alpha +IL-1 beta stimulation.
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Our results indicate that lung epithelial cells not only provide a harboring site for neutrophils to be activated, but also amplify the neutrophil sequestration in the lung by releasing IL-8. Moreover, the release of IL-8 is dependent on the adherence between neutrophils and lung epithelial cells. Final Decision: yes