ACTIVATION AND LOCALIZATION OF TRANSCRIPTION FACTOR, NUCLEAR FACTOR-KAPPA-B, IN ASTHMA

Asthma is associated with increased expression of inflammatory protein s including cytokines, enzymes, and adhesion molecules. Induction of m any of the genes for these proteins is regulated by the transcription factor, nuclear factor-kappa B (NF-kappa B). We therefore examined whe ther airway cells from patients with asthma show increased activation of NF-kappa B. Nuclear proteins were extracted from cells of induced s putum and from bronchial biopsies of normal subjects and patients with asthma. NF-kappa B-binding to its consensus DNA binding site, as inve stigated with P-32-labeled oligonucleotides and electrophoretic-mobili ty-shift assay, showed a 2.5-fold increase (p < 0.003) in NF-kappa B-D NA binding in induced sputum of asthma patients. Nuclear staining, rep resenting activated NF-kappa B, was observed in macrophages of induced sputum. Immunohistochemical examination of bronchial biopsy specimens with an antibody to p65, a constituent of NF-kappa B, showed more air way epithelial cells with nuclear staining in asthma patients (45.1 +/ - 7.2% versus 20.7 +/- 3.9%; n = 9; p < 0.01), and a 2.5-fold greater number of cells with cytoplasmic staining in the mucosal region (p < 0 .05). Pooled nuclear extracts of bronchial biopsy specimens from asthm a patients showed a 44% greater level of NF-kappa B-DNA binding. Activ ation of NF-kappa B may be the basis for increased expression of many inflammatory genes and for the perpetuation of chronic airway inflamma tion in asthma.