Characteristic DNA methylation profiles in peripheral blood monocytes are associated with inflammatory phenotypes of asthma

Epigenetic changes including DNA methylation caused by environmental exposures may contribute to the heterogeneous inflammatory response in asthma. Here we investigate alterations in DNA methylation of purified blood monocytes that are associated with inflammatory phenotypes of asthma. Peripheral blood was collected from adults with eosinophilic asthma (EA; n=21), paucigranulocytic asthma (PGA; n=22), neutrophilic asthma (NA; n=9), and healthy controls (n =10). Blood monocytes were isolated using ficoll density gradient and immuno-magnetic cell separation. Bisulfite converted genomic DNA was hybridised to Illumina Infinium Methylation27 arrays, and analysed for differential methylation using R/Bioconductor packages