Day 6 at the reduction stage of acute respiratory illness. (A) Comparative analysis of acute respiratory illness-associated genes of D6 indicated that n = 66 were shared amongst the Healthy, Allrg Rhin and Asm NoEx groups (box). Complete gene lists generated for each comparison are outlined in Table S1 in Additional file 2. (B) Kinetics of shared-D6 gene expression in each study group (n = 66 probes/time point). (C) Hierarchical clustering analysis of the D6 versus D2 microarray expression of the shared-D6 genes. (D) Quantitative real-time PCR confirmation of select shared-D6 gene expression. Horizontal line depicts mean. *P = <0.05, **P ≤0.01. Number of matched D2 and D6 samples from each group used for quantitative real-time PCR assays are indicated below. (E) Influence of medication use on shared-D6 gene expression for all asthmatics. Horizontal line depicts mean. BIRC5, Baculoviral IAP repeat containing 5; CCNB2, Cyclin B2; DLGAP5, Discs, large (Drosophila) homolog-associated protein 5; GCN, fold change in normalized gene copy number; D2, day 2; D6, day 6; ICS, inhaled corticosteroids; NS, nasal steroids.