Detection of autoantibodies in dermatomyositis

Abstract

Some autoantibodies have been identified to be closely associated with the clinical phenotypes and prognosis of dermatomyositis, such as anti-melanoma differentiation-associated gene 5 (MDA5) antibody, anti-transcriptional intermediary factor 1-γ (TIF-1γ) antibody, anti-nuclear matrix protein-2 (NXP-2) antibody, anti-glycyl-tRNA synthetase (anti-EJ) antibody, anti-nucleosome remodelling and histone deacetylase complex (anti-Mi-2) antibody, anti-histidyl-tRNA synthetase (anti-Jo-1) antibody, and so on. Anti-MDA5, anti-EJ and anti-Jo-1 antibodies are all related to dermatomyositis complicated by interstitial lung disease, especially anti-MDA5 antibody, which is significantly associated with the occurrence, disease activity and high mortality of dermatomyositis complicated by interstitial lung disease. Usually, anti-MDA5 antibody-positive patients have poor response to conventional immunosuppressive treatments. Anti-TIF-1γ and anti-NXP-2 antibodies are related to cancer-associated dermatomyositis. Moreover, anti-TIF-1γ and anti-NXP-2 antibodies are linked to some other distinctive clinical phenotypes of dermatomyositis. For example, obviously increased occurrence of psoriasis-like lesions and hyperkeratotic papules of palms is observed in anti-TIF-1γ antibody-positive patients, while muscle weakness in the forearms, lower legs and neck occurs more commonly in anti-NXP-2 antibody-positive patients. However, anti-Mi-2 antibody-positive patients have significantly decreased risk of interstitial lung disease and prolonged duration of treatment. Thus, wide application of the detection of these autoantibodies will be helpful to guide the diagnosis and treatment of dermatomyositis. Key words: Dermatomyositis; Autoantibodies; Antibodies, anti-MDA5; Antibodies, anti-TIF-lγ; Antibodies, anti- NXP-2; Antibodies, anti-EJ; Antibodies, anti- Mi-2; Antibodies, anti- Jo-1