miR-155 and functional proteins of CD8+ T cells as potential prognostic biomarkers for relapsing-remitting multiple...

Multiple Sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) that results in neurological deficits in patients leading to disabilities which are evaluated on a scale known as the Expanded Disability Status Scale (EDSS). The most prevalent subtype of the disease is Relapsing-Remitting Multiple sclerosis (RRMS). One of the key players in MS pathogenesis is CD8+ T cells present in abundance in MS lesions expressing surface receptors, intracellular adhesion molecule (ICAM1) and integrin Subunit Beta 2 (ITGB2). These proteins are crucial for migration through the blood-brain barrier (BBB) and secondary stimulatory signal, along with the cytotoxic proteins perforin and granzymeB that attack oligodendrocytes. MicroRNAs (miRNAs) are small non-coding RNAs that play a substantial regulatory role in various disease pathogeneses through post-transcriptional modifications, and miR-155 shows potential for its use as a biomarker of the disease. The study aims at investigating the expression of miR-155, ICAM1, ITGB2, perforin and GranzymeB in CD8+ T cells of RRMS patients receiving different treatment regimens and how these genes correlate with patients' EDSS and miR-155 expression.

Gene expression of miR-155, ICAM1, ITGB2, perforin and granzymeB was evaluated using RT-qPCR in CD8+ T cells isolated from blood samples of RRMS patients and compared to healthy controls.

Results showed downregulation of miR-155 and upregulation of surface receptors and cytotoxic proteins in CD8+T cells with significant correlation with each other and patients' EDSS.

This study helps pave the road for the discussed genes for their use as potential biomarkers of disease disability and future investigations on their regulatory roles in disease pathogenesis.