Table 1.
Myositis-specific autoantibodies, target autoantigens, and clinical associations
| Frequency, percentage | ||||
|---|---|---|---|---|
| Autoantibody | Target autoantigen | Clinical associations | Adults | JDM |
| Anti-ARS | Amino-acyl-tRNA synthetase | Anti-synthetase syndrome | Overall: 30-40 | Overall: 1-3 |
| - Jo-1 | - Histidyl | Myositis | Jo-1: 15-20 | |
| - PL7 | - Theronyl | Interstitial lung disease | PL7: <5 | |
| - PL12 | - Alanyl | Raynaud phenomenon | PL12: <5 | |
| - OJ | - Isoleucyl | Arthritis | OJ: <5 | |
| - EJ | - Glycyl | Mechanic's hands | EJ: <5 | |
| - KS | - Asparaginyl | Fever | KS: <5 | |
| - Ha | - Tyrosyl | Ha: <1 | ||
| - Zo | - Phenylalanyl | Zo: <1 | ||
| Anti-Mi-2 | Nucleosome remodeling deacetyalse complex (NuRD) | DM | < 10 | 4-10 |
| Anti-p155/140 | Transcriptional intermediary factor 1 gamma (TIF1-γ) | JDM: DM and ulceration | 13-21 | 22-29 |
| Adults: DM and malignancy | ||||
| Anti-p140 | Nuclear matrix protein 2 (NXP2) | JDM: DM and calcinosis | < 5 | 23 |
| Adults: DM and ILD | ||||
| Anti-SAE | Small ubiquitin-like modifier activating enzyme (SAE) | DM | < 5 | < 1 |
| Anti-CADM-140 | Melanoma differentiation-associated gene 5 (MDA5) | CADM and ILD | 50-73 CADM (not in Caucasians) | Not known |
| Anti-SRP | Signal recognition particle (SRP) | Necrotizing myopathy | 5-10 | < 3 |
| Anti-200/100 | Unknown 100- and 200-kDa proteins | Necrotizing myopathy | < 10 necrotizing myopathy | Not known |
ARS, amino-acyl-tRNA synthetase; CADM, clinically amyopathic dermatomyositis; DM, dermatomyositis; ILD, interstitial lung disease; JDM, juvenile dermatomyositis.