Animal Models of Idiopathic Inflammatory Myopathies: Bridging Mechanistic Insights and Clinical Translation

Idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of autoimmune diseases with wide variation in pathogenesis, clinical presentation, and serological profiles, leading to substantial differences in diagnosis, classification, treatment response, and prognosis among patients. Although decades of progress have been made in understanding myositis-specific autoantibodies and molecular pathology, important gaps remain in elucidating disease mechanisms and identifying effective therapeutic targets. Therefore, animal models that recapitulate key characteristics of human IIMs provide an indispensable platform for addressing current limitations in mechanistic research and promoting translational studies. This review comprehensively discusses animal models related to the major clinical–serological subtypes of IIMs, including polymyositis-like T-cell-mediated models, dermatomyositis models, inclusion body myositis models, antisynthetase syndrome models, and immune-mediated necrotizing myopathy models. Particular attention is given to model construction, pathological phenotypes, dominant immune mechanisms, therapeutic applications, and translational limitations. By organizing current models according to subtype-related pathological and immunological features, this narrative review aims to provide a clearer framework for selecting appropriate experimental systems and to facilitate more precise, mechanism-driven myositis research.