Systemic autoimmune diseases are characterized by specific targeting of a limited group of ubiquitously expressed autoantigens by the immune system. This review examines the mechanisms underlying their selection as immune targets. Initiation of autoimmune responses likely reflects the presentation of antigens with a distinct structure not previously encountered by the immune system, in a proimmune context (injury, malignancy, or infection). Causes of modified structure include somatic mutation and posttranslational modifications (including citrullination and proteolysis). Many autoantigens are components of multimolecular complexes, and some of the other components may provide adjuvant activity. Propagation of autoimmune responses appears to reflect a bidirectional interaction between the immune response and the target tissues in a mutually reinforcing cycle: Immune effector pathways generate additional autoantigen, which feeds further immune response. We propose that this resonance may be a critical principle underlying disease propagation, with specific autoantigens functioning as the hubs around which amplification occurs.

中文翻译：

---

自身抗原作为自身免疫性风湿性疾病的起始和传播伙伴。

系统性自身免疫疾病的特征是免疫系统特异性靶向有限组的泛在表达的自身抗原。这篇综述检查了将其选择为免疫靶标的基础机制。自身免疫反应的启动可能反映了在免疫前的情况下（损伤，恶性或感染）具有免疫系统先前未遇到的独特结构的抗原的呈递。结构改变的原因包括体细胞突变和翻译后修饰（包括瓜氨酸化和蛋白水解）。许多自身抗原是多分子复合物的成分，其他一些成分可能提供佐剂活性。自身免疫应答的传播似乎反映了免疫应答与靶组织之间在双向循环中的双向相互作用：免疫效应子途径会产生额外的自身抗原，从而进一步提供免疫应答。我们建议这种共振可能是疾病传播的关键原理，特定的自身抗原起着围绕扩增作用的枢纽的作用。