Epithelial Barrier Dysfunction in Down Syndrome: A Gateway to Chronic Lung Injury?

This scientific review examines how intrinsic airway epithelial dysfunction in Down syndrome (trisomy 21) increases respiratory morbidity through three mechanisms: impaired tight junction integrity, compromised mucus clearance, and dysregulated interferon-driven immune signaling due to chromosome 21 gene triplication. The authors propose an integrated pathophysiological model linking epithelial barrier instability to chronic inflammation and suggest targeted therapeutic approaches to strengthen epithelial function.