Autoantibodies to agrin in myasthenia gravis patients

Bin Zhang, Chengyong Shen, Beverly Bealmear, Samia Ragheb, Wen Cheng Xiong, Richard A. Lewis, Robert P. Lisak, Lin Mei

Research output: Contribution to journalArticlepeer-review

137 Scopus citations

Abstract

To determine if patients with myasthenia gravis (MG) have antibodies to agrin, a proteoglycan released by motor neurons and is critical for neuromuscular junction (NMJ) formation, we collected serum samples from 93 patients with MG with known status of antibodies to acetylcholine receptor (AChR), muscle specific kinase (MuSK) and lipoprotein-related 4 (LRP4) and samples from control subjects (healthy individuals and individuals with other diseases). Sera were assayed for antibodies to agrin. We found antibodies to agrin in 7 serum samples of MG patients. None of the 25 healthy controls and none of the 55 control neurological patients had agrin antibodies. Two of the four triple negative MG patients (i.e., no detectable AChR, MuSK or LRP4 antibodies, AChR-/MuSK-/LRP4-) had antibodies against agrin. In addition, agrin antibodies were detected in 5 out of 83 AChR+/MuSK-/LRP4- patients but were not found in the 6 patients with MuSK antibodies (AChR-/MuSK+/LRP4-). Sera from MG patients with agrin antibodies were able to recognize recombinant agrin in conditioned media and in transfected HEK293 cells. These sera also inhibited the agrin-induced MuSK phosphorylation and AChR clustering in muscle cells. Together, these observations indicate that agrin is another autoantigen in patients with MG and agrin autoantibodies may be pathogenic through inhibition of agrin/LRP4/MuSK signaling at the NMJ.

Original languageEnglish (US)
Article numbere91816
JournalPloS one
Volume9
Issue number3
DOIs
StatePublished - Mar 14 2014

ASJC Scopus subject areas

  • General

Fingerprint

Dive into the research topics of 'Autoantibodies to agrin in myasthenia gravis patients'. Together they form a unique fingerprint.

Cite this