Regulatory T (Treg) cells, a subtype of immunosuppressive CD4⁺ T cells, are vital for maintaining immune homeostasis in healthy people. Forkhead box protein P3 (FOXP3), a member of the forkhead-winged-helix family, is the pivotal transcriptional factor of Treg cells. The expression, post-translational modifications, and protein complex of FOXP3 present a great impact on the functional stability and immune plasticity of Treg cells in vivo. In particular, the mutation of FOXP3 can result in immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, which is a rare genetic disease mostly diagnosed in early childhood and can soon be fatal. IPEX syndrome is related to several manifestations, including dermatitis, enteropathy, type 1 diabetes, thyroiditis, and so on. Here, we summarize some recent findings on FOXP3 regulation and Treg cell function. We also review the current knowledge about the underlying mechanism of FOXP3 mutant-induced IPEX syndrome and some latest clinical prospects. At last, this review offers a novel insight into the role played by the FOXP3 complex in potential therapeutic applications in IPEX syndrome.

调节性T（Treg）细胞是免疫抑制性CD4 ⁺ T细胞的一种亚型，对维持健康人的免疫稳态至关重要。叉头翅螺旋家族的成员叉头盒蛋白P3（FOXP3）是Treg细胞的关键转录因子。FOXP3的表达，翻译后修饰和蛋白质复合物对体内Treg细胞的功能稳定性和免疫可塑性产生了重大影响。尤其是，FOXP3的突变可导致免疫失调，多内分泌病，肠病，X连锁（IPEX）综合征，这是一种罕见的遗传疾病，主要在儿童早期就被诊断出，并可能很快致命。IPEX综合征与几种表现有关，包括皮炎，肠病，1型糖尿病，甲状腺炎等。在这里，我们总结了有关FOXP3调节和Treg细胞功能的一些最新发现。我们还将回顾有关FOXP3突变体诱导的IPEX综合征的潜在机制的最新知识以及一些最新的临床前景。最后，本文对FOXP3复合体在IPEX综合征潜在治疗应用中的作用提供了新颖的见解。