Loss of p73 Expression Contributes to Chronic Obstructive Pulmonary Disease

Area of Science:

• Pulmonary Medicine
• Cell Biology
• Genetics

Background:

• Multiciliated cell (MCC) loss is observed in chronic obstructive pulmonary disease (COPD) airways, but its contribution to lung pathology is unknown.
• The role of p73 in airway epithelium and its connection to COPD pathogenesis requires investigation.

Purpose of the Study:

• To determine if p73 deficiency induces a COPD-like phenotype in mice.
• To investigate the impact of smoking and COPD on p73 expression in airway epithelium.

Main Methods:

• Generated p73-deficient mice (p73Δairway) lacking MCCs.
• Analyzed lung pathology using microscopy, flow cytometry, and lung function tests.
• Examined p73 expression in response to cigarette smoke in vitro and in vivo, and in human samples from smokers and COPD patients.

Main Results:

• p73Δairway mice exhibited MCC absence, neutrophilic inflammation, emphysema-like remodeling, and secretory cell loss.
• Cigarette smoke exposure suppressed p73 expression in airway cells.
• Reduced p73 mRNA in smokers and decreased p73-expressing MCCs in COPD patients compared to controls.

Conclusions:

• Loss of functional p73 in murine airway epithelium leads to MCC absence and promotes COPD-like lung pathology.
• Reduced p73 expression in smokers and COPD patients may contribute to MCC dysfunction or loss, potentially driving COPD pathogenesis.