Project description:We performed genome-wide profiling of miRNA expression in the airway epithelial compartment in asthma to identify miRNA pathways associated with epithelial abnormalities using miRNA microarrays and real-time PCR. We also sought to identify the effect of inhaled corticosteroids (ICS) on airway epithelial miRNA expression Samples were obtained from airway epithelial cells by bronchoscopic brushing from three groups of subjects: Healthy Controls ( N=12), Steroid Naïve Asthma (N=16), Steroid-requiring Asthma (N=19).
Project description:Airway epithelial brushings were obtained for microarray analysis by research bronchoscopy in 62 subjects with mild-to-moderate asthma not on inhaled steroids and 43 healthy controls. Asthma subjects were stratified into 2 subgroups, Th2 high and Th2 low asthma, based on their expression of a three-gene signature of Type 2 inflammation: POSTN, SERPINB2, and CLCA1. Gene expression comparisons were made between: 1. asthmatics and healthy controls, and 2. Th2 high asthma and Th2 Low asthma/Healthy controls. The gene expression alterations most associated with asthma were then used in gene set enrichment analyses and gene signature development to compare this asthma dataset to COPD gene expression datasets.
Project description:Airway epithelial brushings were obtained for microarray analysis by research bronchoscopy in 62 subjects with mild-to-moderate asthma not on inhaled steroids and 43 healthy controls. Asthma subjects were stratified into 2 subgroups, Th2 high and Th2 low asthma, based on their expression of a three-gene signature of Type 2 inflammation: POSTN, SERPINB2, and CLCA1.
Project description:Molecular profiling studies in asthma cohorts have identified a Th2-driven asthma subtype, characterized by elevated lower airway expression of POSTN, CLCA1 and SERPINB2. To assess upper airway gene expression as a potential biomarker for lower airway Th2 inflammation, we assayed upper airway (nasal) and lower airway (bronchial) epithelial gene expression, serum total IgE, blood eosinophils and serum periostin in a cohort of 54 allergic asthmatics and 30 matched healthy controls. 23 of 51 asthmatics in our cohort were classified as âTh2 highâ based on lower airway Th2 gene signature expression. Consistent with this classification, âTh2 highâ subjects displayed elevated total IgE and blood eosinophil levels relative to âTh2 lowâ subjects. Upper airway Th2 signature expression was significantly correlated with lower airway Th2 signature expression (r=0.44), with similar strength of association as serum total IgE and blood eosinophils, known biomarkers of Th2 inflammation. In an unbiased genome-wide scan, we identified 8 upper airway genes more strongly correlated with lower airway Th2 gene signature expression (r=0.58), including Eotaxin-3 (CCL26), Galectin-10 (CLC) and Cathepsin-C (CTSC). Asthmatics classified as âTh2 highâ using this 8-gene signature show similar serum total IgE and blood eosinophil levels as âTh2 highâ asthmatics classified using lower airway Th2 gene signature expression. We have identified an 8-gene upper airway signature correlated with lower airway Th2 inflammation, which may be used as a diagnostic biomarker for Th2-driven asthma. Upper airway (nasal) and lower airway (bronchial) epithelial brushings obtained from a cohort of 54 allergic asthmatics and 30 matched healthy controls were profiled by gene expression by microarray. Subjects were assayed for gene expression, serum total IgE, blood eosinophils and serum periostin.