Global transcriptome profiling in peripheral blood mononuclear cells identifies dysregulation of immune processes in individuals with radiologically isolated syndrome

The presence of brain/spinal white matter lesions typical for multiple sclerosis (MS) in asymptomatic individuals is known as ‘radiologically isolated syndrome’ (RIS). Allow for the established fact that RIS patients are at high risk of MS development, understanding the causes underlying RIS onset and the variability of its conversion to MS are of great importance. In order to investigate RIS-specific transcription signature we perfromed high-throughput RNA sequencing in peripheral blood mononuclear cells (PBMCs) of 8 RIS patients and 8 age- and sex-matched healthy controls. We identified 57 differentially expressed genes (DEGs), which levels differed by more than 2 times when compared these groups (FDR p value < 0.05). Gene ontology enrichment analysis in the "biological process" category revealed 16 signalling pathways significantly overrepresented by identified DEGs. The most significant changes in gene expression in PBMCs of RIS patients occur in pathways involved in regulation of the immune response, cytokine and chemokine signaling, cytokine production, and leukocyte migration. In general, analyzing the global transcriptome we demonstrated the dysregulation of immune processes in PBMCs of RIS patients, confirming the current assumption that RIS represents the preclinical stage and/or subclinical form of MS. We performed RNA-seq in peripheral blood mononuclear cells of 8 radiologically isolated syndrom (RIS) patients and 8 healthy controls (HC).