High levels of serum interleukin-6 are associated with disease activity in myasthenia gravis

J Neuroimmunol. 2021 Sep 15;358:577634. doi: 10.1016/j.jneuroim.2021.577634. Epub 2021 Jun 17.


Myasthenia gravis (MG), a neuromuscular junction disorder, is caused by pathogenic autoantibodies. Interleukin-6 (IL-6) plays important roles in T helper 17 (Th17), T follicular helper (Tfh), and B cell activations as well as in antibody production. This study aimed to evaluate the clinical significance of serum IL-6 level as a biomarker of disease activity in patients with anti-acetylcholine receptor (AChR) antibody-positive MG. In the present study, serum IL-6 levels were measured in 93 treatment-naïve patients with anti-AChR antibody-positive MG and compared with those in 101 controls. Moreover, correlations between serum IL-6 levels and clinical characteristics were analyzed. Serum IL-6 levels were significantly higher in patients with anti-AChR antibody-positive MG than in controls (median [interquartile range], 2.5 [1.5-8.3] pg/mL vs. 1.5 [1.5-3.2] pg/mL, P < 0.001). The serum levels were correlated with the MG Foundation of America clinical classification (Spearman's ρ = 0.27; P < 0.01) and decreased following immunosuppressive treatment in parallel with disease activity (P = 0.01). In conclusion, IL-6 is involved in the pathogenesis of anti-AChR antibody-positive MG and could be a therapeutic target in MG.

Keywords: Anti-acetylcholine receptor antibody; Biomarker; Disease activity; Interleukin-6; Myasthenia gravis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Autoantibodies / blood*
  • Biomarkers / blood
  • Disease Progression*
  • Female
  • Humans
  • Interleukin-6 / blood*
  • Male
  • Middle Aged
  • Myasthenia Gravis / blood*
  • Myasthenia Gravis / diagnosis*


  • Autoantibodies
  • Biomarkers
  • IL6 protein, human
  • Interleukin-6