Jantima Tanboon1,2, Akinori Uruha3, Werner Stenzel3, Ichizo Nishino1,2. 1. Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan. 2. Department of Genome Medicine Development, Medical Genome Center (MGC), National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan. 3. Department of Neuropathology, Charité - Universitätsmedizin, Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin, Germany.
Abstract
PURPOSE OF REVIEW: Discoveries of myositis-specific antibodies, transcriptomic signatures, and clinicoseropathological correlation support classification of idiopathic inflammatory myopathies (IIM) into four major subgroups: dermatomyositis, immune-mediated necrotizing myopathy (IMNM), antisynthetase syndrome (ASS), and inclusion body myositis (IBM) whereas leaving polymyositis as a historical nonspecific diagnosis of exclusion. This review summarizes and comments on recent knowledge regarding the major subgroup of IIM. RECENT FINDINGS: Type 1 interferon (IFN1) pathway activation is the most prominent in dermatomyositis whereas type 2 interferon (IFN2) pathway activation is high in IBM and ASS; neither pathway is distinct in IMNM. Myxovirus-resistant protein A, IFN1 surrogate marker, is now one of definite dermatomyositis muscle biopsy criteria in the new 2018 European Neuromuscular Centre classification of dermatomyositis; the classification emphasizes on different categorization with and without dermatomyositis-specific antibody result. Novel HLA loci associated with anti-TIF1-γ, anti-Mi-2, and anti-Jo-1 antibodies in Caucasian population are identified. Associations of chaperon-assisted selective autophagy (CASA) and complement-mediated autoimmunity in IMNM as well as highly differentiated T cells in IBM are discovered. SUMMARY: Current IIM classification requires integrated clinicoseropathological approaches. Additional information, such as transcriptomics, HLA haplotyping, and potential biomarkers help tailoring categorization that may have future diagnostic and therapeutic implications.
PURPOSE OF REVIEW: Discoveries of myositis-specific antibodies, transcriptomic signatures, and clinicoseropathological correlation support classification of idiopathic inflammatory myopathies (IIM) into four major subgroups: dermatomyositis, immune-mediated necrotizing myopathy (IMNM), antisynthetase syndrome (ASS), and inclusion body myositis (IBM) whereas leaving polymyositis as a historical nonspecific diagnosis of exclusion. This review summarizes and comments on recent knowledge regarding the major subgroup of IIM. RECENT FINDINGS: Type 1 interferon (IFN1) pathway activation is the most prominent in dermatomyositis whereas type 2 interferon (IFN2) pathway activation is high in IBM and ASS; neither pathway is distinct in IMNM. Myxovirus-resistant protein A, IFN1 surrogate marker, is now one of definite dermatomyositis muscle biopsy criteria in the new 2018 European Neuromuscular Centre classification of dermatomyositis; the classification emphasizes on different categorization with and without dermatomyositis-specific antibody result. Novel HLA loci associated with anti-TIF1-γ, anti-Mi-2, and anti-Jo-1 antibodies in Caucasian population are identified. Associations of chaperon-assisted selective autophagy (CASA) and complement-mediated autoimmunity in IMNM as well as highly differentiated T cells in IBM are discovered. SUMMARY: Current IIM classification requires integrated clinicoseropathological approaches. Additional information, such as transcriptomics, HLA haplotyping, and potential biomarkers help tailoring categorization that may have future diagnostic and therapeutic implications.
Authors: Corinna Preuße; Barbara Paesler; Christopher Nelke; Derya Cengiz; Thomas Müntefering; Andreas Roos; Damien Amelin; Yves Allenbach; Akinori Uruha; Carsten Dittmayer; Andreas Hentschel; Marc Pawlitzki; Sarah Hoffmann; Sara Timm; Sarah Leonard Louis; Nora F Dengler; Heinz Wiendl; Jan D Lünemann; Albert Sickmann; Baptiste Hervier; Sven G Meuth; Udo Schneider; Anne Schänzer; Sabine Krause; Stylianos Tomaras; Eugen Feist; Rebecca Hasseli; Hans-Hilmar Goebel; Laure Gallay; Nathalie Streichenberger; Olivier Benveniste; Werner Stenzel; Tobias Ruck Journal: Acta Neuropathol Date: 2022-05-25 Impact factor: 15.887