Expression of the inflammatory regulator A20 correlates with lung function in patients with cystic fibrosis

BackgroundA20 and TAX1BP1 interact to negatively regulate NF-κB-driven inflammation. A20 expression is altered in F508del/F508del patients. Here we explore the effect of CFTR and CFTR genotype on A20 and TAX1BP1 expression. The relationship with lung function is also assessed.MethodsPrimary nasal epithelial cells (NECs) from CF patients (F508del/F508del, n = 7, R117H/F508del, n = 6) and controls (age-matched, n = 8), and 16HBE14o- cells were investigated. A20 and TAX1BP1 gene expression was determined by qPCR.ResultsSilencing of CFTR reduced basal A20 expression. Following LPS stimulation A20 and TAX1BP1 expression was induced in control NECs and reduced in CF NECs, broadly reflecting the CF genotype: F508del/F508del had lower expression than R117H/F508del. A20, but not TAX1BP1 expression, was proportional to FEV1 in all CF patients (r = 0.968, p < 0.001).ConclusionsA20 expression is reduced in CF and is proportional to FEV1. Pending confirmation in a larger study, A20 may prove a novel predictor of CF inflammation/disease severity.