Nasal Mucosal miRNA expression in RSV positive infants with mild or severe disease, compared to healthy controls

The aim of this investigation was two-fold: i) to describe miRNAs involved in the immune response to Respiratory syncytial virus (RSV) in a clinical setting in order to inform further research of immune system regulation by miRNAs in RSV or other infections; ii) to discover differences in miRNA expression between disease severity groups. We have therefore profiled miRNA in cytology brushings of the nasal mucosa in infants with RSV disease, comparing them to healthy infants. miRNA microarray identified 26 differentially regulated miRNA which were subsequently analyzed by RT-qPCR. Nasal mucosal samples were taken from RSV positive infants using cytology brushes on admission to hospital after aspiration of nasal secretions. Samples were taken from healthy controls without clinical symptoms of respiratory infection using the same procedure.