[The role of autoantibodies in myositis associated interstitial lung disease]

Myositis-associated interstitial lung disease (M-ILD) is a heterogeneous group of diseases. It can be divided into different subtypes listed below according to different myositis antibodies. (1) ASS-related ILD responds well to glucocorticoid plus immunosuppressant therapy but tends to relapse. (2) Anti-MDA5-related ILD is the worst prognosis of M-ILD with high mortality rate, and most patients die within the first 6 months of the disease course. (3) Non-MDA-5 DM-associated ILD is often mild, and NSIP is the main HRCT pattern. (4) IMNM-associated ILD shows mild clinical symptoms of ILD in majority of the case, and NSIP is also the main HRCT pattern. (5) With MAA-associated ILD, anti-Ku-positive patients are more common complicated with ILD. In addition, the changes of serum levels of myositis antibody are generally positively correlated with disease activity, and titer drop after disease remission. Therefore, myositis antibodies are important immunological biomarkers for clinical typing and prognosis of M-ILD.