Elevated serum levels of C-terminal agrin fragment in acetylcholine receptor antibody-positive myasthenia gravis

J Neuroimmunol. 2024 Nov 15:396:578455. doi: 10.1016/j.jneuroim.2024.578455. Epub 2024 Sep 10.

Abstract

Agrin is essential for neuromuscular junction (NMJ) formation and maintenance. The C-terminal agrin fragment (CAF), generated by neurotrypsin-mediated cleavage of agrin, has been gaining attention as a potential biomarker for sarcopenia. We investigated serum CAF levels in myasthenia gravis (MG), a NMJ disorder. Compared to healthy controls, serum CAF levels were significantly elevated in acetylcholine receptor antibody-positive MG (AChR-MG) patients, but not in muscle-specific kinase antibody-positive MG patients. In AChR-MG, baseline and post-treatment CAF levels inversely correlated with post-treatment MG activities of daily living scores, suggesting that elevated CAF levels may reflect protective mechanisms against AChR-MG pathogenesis, such as improved NMJ regeneration.

Keywords: Agrin; C-terminal agrin fragment; Myasthenia gravis; Neuromuscular junction; Sarcopenia.

MeSH terms

  • Adult
  • Aged
  • Agrin* / blood
  • Agrin* / immunology
  • Autoantibodies* / blood
  • Autoantibodies* / immunology
  • Biomarkers / blood
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myasthenia Gravis* / blood
  • Myasthenia Gravis* / immunology
  • Peptide Fragments* / blood
  • Peptide Fragments* / immunology
  • Receptors, Cholinergic* / immunology
  • Young Adult

Substances

  • Agrin
  • Receptors, Cholinergic
  • Autoantibodies
  • Peptide Fragments
  • C-terminal agrin fragment
  • Biomarkers