Analyzing PD-1 expression level in PBMC of multiple sclerosis patients

Abstract

Objective: Multiple sclerosis (MS) is an autoimmune disease with inflammatory and demyelinating lesions in the nervous system, characterized by lymphocytic infiltration and damage to axons. In some studies, conducted in recent years, the role of PD-1 in the regeneration of nerve myelin in patients with MS has been mentioned using experimental models and oligodendrocytes, which is a new treatment strategy for MS by restoring myelin. The aim of this study is to investigate the level of PD-1 gene expression in PBMC of MS patients. Methods: In this study, first of all, 40 patients referred to the hospital, in whom multiple sclerosis was diagnosed by a specialist based on diagnostic criteria, and 40 control group without autoimmune disease, which is 5% of all participants. 30 blood samples were taken and PBMC was separated and the participants' RNA was extracted, then the cDNA synthesis step was performed, and then the expression level of PD-1 was determined by real time-PCR using the Cybergreen method. The difference of the variables between the groups was checked with proportional statistical tests. In statistical tests, p-value < 0.05 was considered significant. Results: The average age in the control group was 37.55 ± 7.14 years and in the MS group was 40.60 ± 10.54 years. In the control group, 10 participants (2.5%) and in the MS group, 34 participants (85%) were female. In the MS group, 33 (82.5%) of the patients had relapsing-remitting (RR) type of MS disease. All the control subjects were negative for FH and in the MS group, 9 people (22.5%) were positive for FH. Our results also showed that there was a significant decrease in PD-1 expression in MS patients compared to healthy subjects (P=0.01). The difference in average expression of PD-1 in sick and healthy female participants is not significant (P=0.082). Also, the statistical analysis showed a statistically significant difference in the expression of this gene in women with MS and healthy men (P=0.013). The average expression level of this gene in control subjects and in the group with MS, at ages over 40 years, this difference was statistically significant (P=0.021). The statistical difference between the control group and the group of patients with MS with RR type was significant. Also, the sensitivity of PD-1 for the diagnosis of MS was 73.17% and its specificity was 55% (P=0.018), which indicates the diagnostic value of this gene in MS.