Multiple Sclerosis (MS) is an immune-mediated chronic inflammatory disease affecting the central nervous system. The cause of MS is not known and the mechanism of IFN-beta, a disease-modifying treatment (DMT) approved for MS, is not well-understood. Oligonucleotide microarrays were used to study gene expression in plasmacytoid denditic cells (pDCs) which are antigen-presenting cells implicated in MS pathogenesis. We analyzed gene expression in pDCs of healthy controls, untreated and IFN-beta treated MS patients. We were able to identify 60 genes which were abnormally expressed in untreated MS patients and were corrected after treatment with IFN-beta.
Overall design
PDCs were separated from healthy donors and MS patients at two time points: before and 3 months after initiation of treatment with IFN-beta for RNA extraction and hybridization on Affymetrix microarrays. Gene expression data analysis of was done by GeneSpring software (Agilent Technologies). An unpaired t-test was applied to select genes with significant difference in expression between healthy donors and untreated MS patients. A paired t-test was applied to select genes with significant difference in expression in MS patients before and after IFN-beta treatment. To select differentially expressed/regulated genes, the cut-off criteria consisted of a P value < 0.05 and fold change >1.5.