Recent Updates on the Pathogenesis of Inflammatory Myopathies

Abstract

Purpose of review: This review aims to provide a comprehensive and updated overview of autoimmune myopathies, with a special focus on the latest advancements in understanding the role of autoantibodies. We will begin by examining the risk factors and triggers associated with myositis. Next, we will delve into recent research on how autoantibodies contribute to disease pathogenesis. Finally, we will explore the latest innovations in treatment strategies and their implications for our understanding of myositis pathogenesis.

Recent findings: Recent research has revealed that myositis-specific autoantibodies can infiltrate muscle cells and disrupt the function of their target autoantigens, playing a crucial role in disease pathogenesis. Significant advances in treatment include CD19 CAR-T cell therapy, JAK-STAT inhibitors, and novel strategies targeting the type 1 interferon pathway in dermatomyositis. Additionally, the ineffectiveness of complement inhibitors in treating immune-mediated necrotizing myositis has challenged established views on disease mechanisms. Autoimmune myopathies are a collection of disorders significantly influenced by specific autoantibodies that drive disease pathogenesis. This review highlights the critical role of autoantibody research in deepening our understanding of these conditions and discusses recent therapeutic advancements targeting key pathogenic pathways.

Keywords: Antisynthetase Syndrome; Autoantibodies; Dermatomyositis; Immune-mediated Necrotizing Myositis; Inclusion body Myositis; Myositis; Pathogenesis.

Fig. 1

Proposed pathogenesis of idiopathic inflammatory myopathies. The development of myositis is influenced by a complex interplay of pre-existing diseases, microbial infections, medications, genetic predispositions, and environmental exposures. These factors may contribute to the production of myositis-specific autoantibodies, which have been found to accumulate within the muscle tissue of patients. Recent research has linked the pathogenesis of myositis to the intracellular actions of these autoantibodies, disrupting the function of their specific autoantigens. This disruption may contribute to muscle cell toxicity and inflammation.