Airway Epithelial Telomere Dysfunction Drives Remodeling Similar to Chronic Lung Allograft Dysfunction

Area of Science:

• Pulmonary Medicine
• Cell Biology
• Transplantation Immunology

Background:

• Telomere dysfunction is linked to fibrotic lung diseases, including chronic lung allograft dysfunction (CLAD), a major cause of lung transplant failure.
• The role of short telomeres as a cause or consequence of CLAD pathology remains unclear.

Purpose of the Study:

• To investigate whether telomere dysfunction contributes to the pathological changes observed in CLAD.
• To determine if isolated telomere dysfunction in airway epithelial cells can induce CLAD-like lung remodeling and fibrosis.

Main Methods:

• Histopathological and molecular analysis of human CLAD lungs, including teloFISH for telomere length and senescence marker assessment.
• Generation and analysis of a mouse model (SCGB1a1-creTRF1) with tamoxifen-inducible telomere dysfunction in airway club cells.

Main Results:

• Human CLAD lungs showed shortened telomeres, increased type II alveolar cells, and senescence markers in lung epithelial cells.
• Induced telomere dysfunction in mouse airway epithelial cells resulted in obstructive/restrictive lung physiology, airway obliteration, fibrosis, and senescence.
• The mouse model exhibited decreased SCGB1a1 expression and CLAD-like pathology.

Conclusions:

• Telomere dysfunction, specifically in airway epithelial cells, can induce airway-centric lung remodeling and fibrosis resembling CLAD.
• These findings identify lung epithelial cell telomere dysfunction as a potential molecular driver of CLAD.