Table 1_Emerging B and plasma cell-targeting immune therapies in idiopathic inflammatory myopathies.docx

Autoantibodies play a crucial role in the diagnosis and clinical characterization of idiopathic inflammatory myopathies (IIM). These antibodies are categorized into myositis-specific autoantibodies (MSAs), which are unique to IIM, and myositis-associated autoantibodies (MAAs), which can be seen with other autoimmune diseases. Both plasmablasts and plasma cells contribute to the production of these autoantibodies. Current B cell-targeted therapies, such as rituximab, have shown promise in refractory IIM, although their limitations – particularly in targeting plasmablasts and plasma cells – highlight the need for alternative agents with greater efficacy. This review discusses the evolving landscape of B cell and plasma cell-targeted immunotherapies in IIM, including next-generation anti-CD20 antibodies, BAFF inhibition, anti-CD19 CAR-T cells, BCMA-targeted therapies, and anti-CD38 antibodies. Most studies on the use of these novel treatment strategies in IIM have reported positive outcomes, although the number of patients treated is small. While these therapies represent a paradigm shift, further randomized clinical trials are needed to identify optimal strategies for IIM management and establish long-term safety and efficacy.

自身抗体在特发性炎性肌病（idiopathic inflammatory myopathies, IIM）的诊断与临床表型特征分析中发挥关键作用。此类抗体可分为两类：一类为肌炎特异性自身抗体（myositis-specific autoantibodies, MSAs），仅为特发性炎性肌病所特有；另一类为肌炎相关性自身抗体（myositis-associated autoantibodies, MAAs），亦可在其他自身免疫性疾病中检出。浆母细胞（plasmablasts）与浆细胞（plasma cells）均参与此类自身抗体的合成与分泌。当前以B细胞为靶点的治疗方案（如利妥昔单抗）在难治性特发性炎性肌病中已展现出一定的应用潜力，但其局限性——尤其是在靶向浆母细胞与浆细胞方面的不足——凸显了开发疗效更优的替代治疗药物的必要性。本综述探讨了特发性炎性肌病中针对B细胞及浆细胞的免疫治疗的发展现状，涵盖新一代抗CD20单克隆抗体、B细胞活化因子（BAFF）抑制剂、抗CD19嵌合抗原受体T细胞（CAR-T）疗法、靶向B细胞成熟抗原（BCMA）的治疗手段以及抗CD38单克隆抗体。目前针对上述新型治疗策略在特发性炎性肌病中应用的多数临床研究均报告了积极疗效，但受试患者规模普遍较小。尽管此类疗法代表了特发性炎性肌病治疗范式的革新，但仍需开展进一步的随机临床试验，以明确该病管理的最优策略，并确定其长期安全性与临床疗效。