Periostin: contributor to abnormal airway epithelial function in asthma?

Area of Science:

• Immunology
• Respiratory Medicine
• Cell Biology

Background:

• Periostin (POSTN) is a potential biomarker for Type-2 mediated eosinophilic airway inflammation in asthma.
• Interleukin-13 (IL-13), a key Type-2 cytokine, is implicated in asthma pathogenesis.
• Epithelial changes, including mucus hypersecretion, are hallmarks of asthma.

Purpose of the Study:

• To investigate the effect of IL-13 on POSTN expression in airway epithelial cells.
• To determine if POSTN contributes to asthma-related epithelial changes, such as epithelial-to-mesenchymal transition (EMT) and mucin production.
• To analyze POSTN expression in bronchial tissues and sputum from asthma patients and healthy controls.

Main Methods:

• Exposure of BEAS-2B cells and primary bronchial epithelial cells (PBECs) to IL-13.
• Assessment of POSTN expression, EMT markers, and mucin gene expression (MMP-9, MUC5B, MUC5AC).
• Analysis of POSTN single-cell gene and protein expression in bronchial biopsies and induced sputum.

Main Results:

• IL-13 upregulated POSTN expression in both cell types, inducing EMT features in BEAS-2B cells.
• IL-13 increased POSTN release from PBECs; exogenous POSTN elevated MMP-9, MUC5B, and MUC5AC expression.
• Bronchial biopsies showed higher POSTN expression in basal epithelial cells of asthma patients versus controls; POSTN protein levels were also elevated.
• Sputum POSTN correlated with eosinophil counts and mucus production in asthma patients.

Conclusions:

• IL-13 stimulates POSTN expression in bronchial epithelial cells, a mechanism potentially contributing to asthma pathogenesis.
• Elevated POSTN in asthma biopsies and its role in promoting mucin gene expression highlight its significance in Type-2 inflammation and mucus secretion.