CCSP G38A polymorphism environment interactions regulate CCSP levels differentially in COPD.

Area of Science:

• Genetics and Molecular Biology
• Pulmonology
• Biochemistry

Background:

• Airway homeostasis impairment in COPD may involve club cell secretory protein (CCSP) deficiency.
• The CCSP G38A polymorphism's role in CCSP regulation and COPD pathogenesis requires investigation.

Purpose of the Study:

• To examine the influence of the CCSP G38A polymorphism on CCSP transcription levels and regulatory mechanisms in COPD.
• To assess the association between CCSP genotype, CCSP levels, and clinical parameters in COPD patients.

Main Methods:

• Genotyping for CCSP G38A polymorphism and measurement of serum/sputum CCSP levels in 66 COPD subjects.
• In vitro study using BEAS-2B cells transfected with CCSP promoter constructs (38G or 38A) exposed to cigarette smoke extract (CSE), LPS, and transcription factors (p53, Nkx2.1).

Main Results:

• COPD patients with the A allele had lower serum/sputum CCSP levels, especially active smokers, and poorer BODE scores.
• In vitro, CSE and LPS more profoundly decreased CCSP transcription in 38A variant cells.
• p53 cotransfection reversed CSE's effect, while Nkx2.1 activated transcription regardless of polymorphism; 38A polymorphism exacerbated CCSP repression by p53 and CSE.

Conclusions:

• Circulating CCSP levels correlate with smoking and the CCSP G38A polymorphism in COPD.
• The CCSP G38A polymorphism influences CCSP promoter activity in response to CSE, LPS, p53, and Nkx2.1, potentially impacting COPD.
• The 38A variant exacerbates CCSP repression, suggesting a role in COPD pathogenesis.