IL-17A and IL-8 mRNA levels in healthy controls and asthmatics. RNA was isolated from induced sputum of healthy controls (n = 11) and asthmatic patients (n = 33) and real time RT-PCR was performed with β-actin, IL-17A and IL-8 specific primers and with VIC-(β-actin) or FAM-(IL-17A, IL-8) labelled specific probes. Results were quantified by the use of a cDNA plasmid-standard and expressed as the ratio of cDNA copy numbers for IL-17A (A-C) or IL-8 (B-D) divided by the cDNA copy numbers for β-actin multiplied by 104 (A-C) or 101 (B-D). Patients were divided in subgroups according to asthma severity following the reviewed GINA criteria  (A, B) and allergic state (allergic state was not known in one patient and two patients with only specific IgE for grass pollen were excluded for the comparison of allergic to non-allergic asthma) (C, D). Open symbols represent patients treated with corticosteroids, closed symbols represent patients without corticosteroid-treatment. Comparisons were performed using the Kruskall-Wallis and Mann-Whitney-U test. The median is indicated with a horizontal line. * = p < 0.05, ** = p < 0.01, *** = p < 0.001 and ns = not significant.
Bullens et al. Respiratory Research 2006 7:135 doi:10.1186/1465-9921-7-135