BioProject

Chronic Fatigue Syndrome (CFS/ME) is a complex multisystem disease, with a pathogenesis that is undetermined. More...

Chronic Fatigue Syndrome (CFS/ME) is a complex multisystem disease, with a pathogenesis that is undetermined. A large cohort of genes demonstrating altered expression in CFS/ME implicates the role of translational regulatory molecules, microRNA (miRNA), in the pathogenesis of this disease. We aimed to define the changes in microRNA expression in peripheral blood mononuclear cell (PBMC) samples in CFS/ME patients. miRNA expression was analysed in PBMC samples taken from CFS/ME patients and healthy controls, using the Ambion Bioarray V1. miRNA demonstrating differential expression were validated by qRT-PCR and analysed in an independent patient cohort in fractionated blood cell populations. The targets of miRNA hsa-miR-99b and hsa-miR-330-3p were then identified by gene expression analysis after transfection into primary NK cells.Microarray analysis identified differential expression of 34 miRNA, all of which were up-regulated. Four of the 34 miRNA had confirmed expression changes by qRT-PCR. Fractionating PBMC samples by cell type from an independent patient cohort identified changes in miRNA expression in NK-cells, B-cells and monocytes with the most significant abnormalities occurring in NK cells. Transfecting primary NK cells with hsa-miR-99b and hsa-miR-330-3p, respectively, resulted in gene expression changes consistent with NK cell activation and diminished cytotoxicity.This study demonstrates altered microRNA expression in the peripheral blood mononuclear cells of CFS/ME patients, which are potential diagnostic biomarkers. The greatest degree of miRNA deregulation was identified in NK cells with targets consistent with cellular activation and altered effector function. Overall design: Total RNA was isolated from PBMC samples obtained from blood samples taken from patients with an established diagnosis of CFS/ME (n=15) and age and sex matched healthy donors (n=30). Duplicate samples were prepared for 7 samples (P100, P103-P108) as technical replicates. Samples P100_1 and C261 failed hybridization quality control and were excluded. Less...