Table 2 Myositis-specific antibodies: target antigens and clinical associations in adult myositis patients
Autoantibody | Immune target | Function of autoantigen | Clinical associations |
|---|---|---|---|
Anti-ARS (Jo-1, PL-7, PL-12, EJ, OJ, KS, Ha, Zo) | tRNA synthetases | Aminoacylation of tRNAs | PM Anti-synthetase syndrome |
Anti-Mi-2 | NuRD subunit | Gene transcription Nucleosome remodeling | “Classic DM” Mild disease |
Anti-TIF1-γ | Transcriptional intermediary factor 1γ | Ubiquitination Gene transcription | Severe DM Cancer-associated DM |
Anti-NXP-2 | Nuclear matrix protein 2 | Gene transcription | Severe DM Cancer-associated DM |
Anti-MDA5 | Melanoma differentiation-associated protein 5 | Innate antiviral response | Amyopathic DM ILD Poor prognosis |
Anti-SAE | SUMO-1 activating enzyme | Protein sumoylation Gene transcription | DM Initially amyopathic DM |
Anti-SRP | Signal recognition particle | Protein translocation across the ER | Necrotizing myopathy |
Anti-HMGCR | 3-Hydroxy-3-methylglutaryl-CoA reductase | Cholesterol biosynthesis | Necrotizing myopathy Prior statin use |