Micro RNA 26a Expression in Peripheral Blood Mononuclear Cells and Correlation with Serum Interleukin-17 in Relapsing Remitting Multiple Sclerosis Patients

Abstract

Multiple sclerosis (MS) is a chronic multifocal inflammatory demyelinating disease with progressive neurodegeneration caused by an autoimmune response to self-antigens in an individual who is genetically susceptible. Clinical symptoms vary depending on the site of neurologic lesions and correlate with the invasion of inflammatory cells across the blood-brain barrier (BBB) result in demyelination and edema. The immunopathogenesis of multiple sclerosis is considered as a complicated picture that needs to be elucidated. The factors that initiate inflammation are still unknown, but it is believed that MS is caused by environmental factors in the host that has genetic susceptibility which trigger a T-cell autoimmune response against the CNS. Primarily it was supposed that a subset of T helper 1 (Th1) which produce interferon γ (IFN-γ) is critical in autoimmunity of MS, however it is now clear that Th17, are the main responsible cells for inflammation and pathogenesis of MS. MS is a very complicated disease and even magnetic resonance imaging (MRI), as a preferred diagnostic method, does not correlate with the disease severity, progression and response to treatment. Therefore, there is a great need for new and more specific biomarkers, which could elucidate pathology as well as provide prognosis of disease and therapeutic response in MS patients In recent years several studies are conducted on the presence and the role of miRNA in MS, suggesting that there are varieties of pathways regulated by miRNA. MiRNAs are a class of endogenous small, non-coding RNAs of average 22 nucleotide long, that regulate gene expression at the post-transcriptional level results in translational repression or mRNA degradation leading to a decrease in encoded protein. In this study, we aimed to detect the expression of miR-26a in peripheral blood mononuclear cells (PBMCs) of relapsing–remitting MS (RRMS) patients during relapsing and remitting phases compared to healthy control subjects and correlate this expression to the level of serum IL17. This study was conducted on 40 patients who are diagnosed as definite multiple sclerosis cases according to MacDonald criteria (relapsing remitting type) and admitted to multiple sclerosis unit at Ain Shams University Hospital with a mean age of (27.75 ±4.21) and 20 healthy control subjects with a mean age of (25.15 ± 2.78) in the period