Transcriptome sequencing (RNA-Seq) of human endobronchial biopsies: asthma versus controls

The cellular and molecular pathways in asthma are highly complex. Increased understanding can be obtained by unbiased transcriptomic analysis (RNA-Seq). We hypothesized that the transcriptomic profile of whole human endobronchial biopsies differs between asthma patients and controls. First, we investigated the feasibility to obtain RNA from whole endobronchial biopsies suitable for RNA-Seq. Second, we examined the difference in transcriptomic profiles between asthma and controls. This cross-sectional study compared 4 steroid-free atopic asthma patients and 5 healthy non-atopic controls. Total RNA of 4 biopsies per subject was prepared for RNA-Seq. Comparison of the numbers of reads per gene in asthma and controls was based on the Poisson distribution. Forty-six genes were differentially expressed between asthma and controls, including pendrin, periostin, and BCL2. Ten gene networks were found involved in cellular morphology, movement, and development. RNA isolated from whole human endobronchial biopsies is suitable for RNA-Seq, showing different transcriptomic profiles between asthma and controls. Novel and confirmative genes were found to be linked to asthma. These results indicate that biological processes in the airways of asthma patients are differently regulated compared to controls, which may be relevant for the pathogenesis and treatment of the disease.