Anti-inflammatory gene therapy directed at the airway epithelium

Cystic fibrosis (CF) is characterised by chronic airway inflammation. Pro-inflammatory mediators in the lung are regulated by the transcription factor nuclear factor kappa B (NF kappa B). We have assessed the effect of adenovirus and liposome-mediated overexpression of the NF kappa B inhibitor I kappa B alpha, as well as liposome-mediated transfection with oligonucleotides resembling NF kappa B consensus binding sites (decoys) in a cystic fibrosis airway epithelial cell line (CFTE). Electrophoretic mobility shift assays (EMSA) were used to assess NF kappa B activity and secretion of the pro-inflammatory cytokine interleukin-8 (IL-8) was measured by ELISA. At a MOI of 30, Ad-I kappa B alpha significantly decreased IL-8 secretion to 60% and 43% of control unstimulated and TNF-alpha stimulated cells, respectively. At this MOI, approximately 70% of cells are transduced. EMSA showed an approximately 50% decrease in NF kappa B activation. Liposome-mediated transfection of I kappa B alpha did not reduce IL-8 secretion, probably due to low transfection efficiency (approximately 5% of cells). Liposome-mediated transfection of CFTE cells with rhodamine-labeled decoy oligonucleotides indicated a transfection efficiency close to 100%. TNF-alpha stimulated IL-8 secretion was reduced by approximately 40% using this approach. EMSA confirmed a significant decrease of NF kappa B activation. Decoy oligonucleotides may be a promising approach for reduction of NF kappa B-mediated pulmonary inflammation.