miRNA expression in EBC

Cystic Fibrosis (CF) is the most common life limiting genetic disorder, characterized by chronic respiratory failure secondary to inflammation and chronic bacterial lung infection. Pseudomonas aeruginosa lung infection is associated with more severe lung disease and rapid progression of respiratory failure when compared to Staphylococcus aureus infection. We hypothesized that a specific signature of epigenetic factors targeting specific gene transcripts contributes to the increased morbidity seen in CF patients with chronic Pseudomonas infection. We collected exhaled breath condensate (EBC) from 27 subjects and evaluated miRNA signatures in these samples using commercial PCR array. We identified predicted mRNA targets and associated signaling pathways using Ingenuity Pathway Analysis. We found 11 differentially expressed miRNAs in EBC of patients infected with Pseudomonas aeruginosa compared to EBC from CF patients who were not chronically infected with Pseudomonas aeruginosa. We extracted RNA from 0.5 mL of EBC from control and CF patients (Pseudomonas infection positive or negative) using the Plasma/Serum RNA Purification Kit. The expression of 1,066 human miRNAs was quantified using the Human miRNome miScript® miRNA PCR Array (QIAGEN, MIHS-3216Z). Results (Ct values) were normalized to global means, and fold changes were calculated using the 2-ΔΔCT method. variable control: Sample C01, Sample C02, Sample C04, Sample C05, Sample C06, Sample C07, Sample C08, Sample C09, Sample C10 variable CF Pseudomonas (+): Sample CF03, Sample CF07, Sample CF08, Sample CF11, Sample CF13, Sample CF14, Sample CF15, Sample CF17, Sample CF18, Sample CF19 variable CF Pseudomonas (-):Sample CF01, Sample CF02, Sample CF04, Sample CF05, Sample CF06, Sample CF09, Sample CF10, Sample CF12, Sample CF16