UCN2 and AIDS: These autoantibodies comprise myositis-specific autoantibodies (MSAs) present in up to 70% of AIM patients (37, 38), including, e.g., anti-Mi-2, anti-SRP, and anti-TIF1g, as well as myositis-associated autoantibodies (MAAs), which may also be found in other AIDs like SLE or systemic sclerosis, including anti-PM-Scl.