Autoimmunity has long been regarded as the polar opposite of immunodeficiency, but clinical and experimental evidence refute this notion. Indeed, numerous inborn or acquired immunodeficiency syndromes are characterized by the development of autoimmune complications in the setting of deficient immune defenses against microbial pathogens. Appreciation that much of the daily business of a healthy immune system is the avoidance of potentially harmful responses to innocuous environmental antigens or components of the host organism helps provide a context for these observations. In this issue of the JCI, Abt and colleagues report on purine nucleoside phosphorylase (PNP) deficiency, exploring the basis for the autoimmune complications that develop in this particular form of T cell immune deficiency and assigning a key role for overactivation of TLR7.

中文翻译：

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免疫缺陷和自身免疫：同伴而不是对立面

长期以来，自身免疫一直被认为是免疫缺陷的对立面，但临床和实验证据驳斥了这一观点。事实上，许多先天性或获得性免疫缺陷综合征的特征是在针对微生物病原体的免疫防御缺陷的情况下发生自身免疫并发症。认识到健康免疫系统的大部分日常工作是避免对无害的环境抗原或宿主生物体成分产生潜在的有害反应，有助于为这些观察提供背景。在本期的JCI中, Abt 及其同事报告了嘌呤核苷磷酸化酶 (PNP) 缺乏症，探索了在这种特殊形式的 T 细胞免疫缺陷中发展的自身免疫并发症的基础，并确定了 TLR7 过度激活的关键作用。