Study of circulating Th17 cells and associated cytokines in myasthenia gravis

Abstract

Objective To investigate the expression of helper T cell 17 (Th17) cells and associated cytokines in patients with myasthenia gravis (MG) and its correlations to the level of anti-acetylcholine receptor (AChR) antibodies. Methods Thirty patients with MG including 16 patients with ocular myasthenia gravis (OMG) and 14 patients with general myasthenia gravis (GMG) were enrolled in the study from September 2016 to December 2017. Flow cytometry was used to calculate the percentage of circulating Th17 cells in the peripheral blood mononuclear cell (PBMC). Real-time reverse transcription polymerase chain reaction (RT-PCR) was used to examine the expression of interleukin-17A (IL-17A) retinoid-related orphan receptor γ (RORγ) mRNA. Enzyme-linked immunosorbent assay (ELISA) was used to detect IL-17A, IL-6, IL-23 and anti-AChR antibodies. Results The percentage of circulating Th17 cells (t = - 3.312, P = 0.002; t = - 2.286, P = 0.030), the expression of the IL-17A level (t = - 4.282, P = 0.004; t = - 2.788, P = 0.007) and RORγ mRNA (t = 4.408, P = 0.001; t = 1.991, P = 0.049) in GMG and OMG group were higher than those in control group with statistical significance. IL-23 was also higher in the GMG group than that in the control group (t = -2.267, P = 0.031). The percentage of Th17 and level of IL-17A were positively correlated with the anti-AChR antibodies (r = 0.851, P = 0.012; r = 0.743, P = 0.025; respectively). Conclusions The high level of Th17 cells and IL-17A may be closely related to the etiology of MG. It must be verified in the future.

DOI:10.3969/j.issn.1672-6731.2019.10.014