IFIH1 and myositis disease: (2) Myositis-specific autoantibodies (MSA): anti-Mi-2, anti-melanoma differentiation-associated protein-5 (anti-MDA-5), anti-nuclear matrix protein-2 (anti-NXP-2),anti -TIF-1 and anti-small ubiquitin-like modifier activating enzyme (anti-SAE)-1/2 [7,14,15,17,18].