Related Experiment Video
Updated: Jun 1, 2026

Detection of Anti-MDA5 Autoantibodies Using HeLa Cells and Immunocytochemistry with Light Microscopy
Published on: October 31, 2025
Autoantibodies against a 43 KDa muscle protein in inclusion body myositis
Mohammad Salajegheh1, Theresa Lam, Steven A Greenberg
1Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts, United States of America. msalajegheh@partners.org
Background:
Inclusion body myositis (IBM) is a poorly understood and refractory autoimmune muscle disease. Though widely believed to have no significant humoral autoimmunity, we sought to identify novel autoantibodies with high specificity for this disease.
Methodology/Principal Findings:
Plasma autoantibodies from 65 people, including 25 with IBM, were analyzed by immunoblots against normal human muscle. Thirteen of 25 (52%) IBM patient samples recognized an approximately 43 kDa muscle protein. No other disease (N = 25) or healthy volunteer (N = 15) samples recognized this protein.
Conclusions:
Circulating antibodies against a 43-kDa muscle autoantigen may lead to the discovery of a novel biomarker for IBM. Its high specificity for IBM among patients with autoimmune myopathies furthermore suggests a relationship to disease pathogenesis.
Related Concept Videos
Myasthenia Gravis: Diagnostic Tests
The edrophonium test is a diagnostic tool for myasthenia gravis. It involves...
Myasthenia Gravis ll: Pathophysiology
Myasthenia Gravis: Overview and Treatment
These antibodies interfere with the function of the nicotinic receptors in three ways: by binding to the receptor and disrupting acetylcholine binding; by causing cross-linking of receptors which leads...
Myocarditis II: Clinical Features and Diagnostic Tests
Myocarditis I: Introduction
Myocarditis III: Medical Management