MicroRNA regulate immune pathways in T-cells in multiple sclerosis (MS) mRNA

MicroRNAs are small noncoding RNA molecules that are involved in the control of gene expression. To investigate the role of microRNA in multiple sclerosis (MS), we performed global microarray analyses of mRNA and microRNA in peripheral blood T-cells from relapsing-remitting MS patients and controls. We identified 2,452 regulated genes and 21 regulated microRNA that differed between MS patients and controls. By Kolmogorov-Smirnov test, 20 of 21 regulated microRNA were shown to affect the expression of their target genes, many of which are involved in the immune system. LIGHT (TNFSF14) was a microRNA target gene significantly decreased in MS. The down-regulation of mir-494 and predicted mRNA-target LIGHT was verified by real-time PCR and we could demonstrate decreased serum levels of LIGHT in MS. Thus, regulated microRNA were significantly associated with both gene and protein expression of a molecule in immunological pathways. These findings indicate that microRNA may be important regulatory molecules in T-cells in MS. Microarray expression analysis of mRNA and miRNA in peripheral blood T-cell of control andMS patients