Clinical data of the subjects investigated.

Data are mean ± SEM of n subjects or the percentage of subjects in a group (in brackets absolute number of subjects). Statistical comparisons were made by One-way ANOVA with post hoc test, Tukey ** indicates a significant difference (pn.k.: not known.§BMI = body mass index (weight (kg)/(length (m2)). Age-dependent cut-off values used to define weight status groups (underweight, normal, overweight) were taken from the global database on body mass index (http://www.who.int/bmi/index.html).§§indicates FEV1 (% pred.)age 20 for patients with cystic fibrosis, calculated according to Schluchter et al 2006,§§§data were calculated from all mean FEV1 (% pred.) available and covered an average of at least 3 years before the latest sampling point with four values each year per patient.§§§§Serum and lavage samples were not available as pairs in all subjects; thus the numbers of each measurement are different.There was no correlation between the neutrophils in BAL (%) or the IgG in serum (ratio to upper normal value) and the FEV1 (% pred.).