Laboratory of Medical Biotechnology, Institute of Biomedical Chemistry, Pogodinskaya st. 10/8, 119121 Moscow, Russia.
Research Center of Neurology, Volokolamskoe Shosse, 80, 125367 Moscow, Russia.
Cells. 2023 Dec 29;13(1):77. doi: 10.3390/cells13010077.
The maturation, development, and function of regulatory T cells (Tregs) are under the control of the crucial transcription factor Forkhead Box Protein 3 (FoxP3). Through alternative splicing, the human FoxP3 gene produces four different splice variants: a full-length variant (FL) and truncated variants with deletions of each of exons 2 (∆2 variant) or 7 (∆7 variant) or a deletion of both exons (∆2∆7 variant). Their involvement in the biology of Tregs as well as their association with autoimmune diseases remains to be clarified. The aim of this work was to induce a single FoxP3 splice variant in human Tregs by splice switching oligonucleotides and to monitor their phenotype and proliferative and suppressive activity. We demonstrated that Tregs from peripheral blood from patients with multiple sclerosis preferentially expressed truncated splice variants, while the FL variant was the major variant in healthy donors. Tregs with induced expression of truncated FoxP3 splice variants demonstrated lower suppressive activity than those expressing FL variants. Reduced suppression was associated with the decreased expression of Treg-associated suppressive surface molecules and the production of cytokines. The deletion of exons 2 and/or 7 also reduced the cell proliferation rate. The results of this study show an association between FoxP3 splice variants and Treg function and proliferation. The modulation of Treg suppressive activity by the induction of the FoxP3 FL variant can become a promising strategy for regenerative immunotherapy.
调节性 T 细胞（Tregs）的成熟、发育和功能受关键转录因子叉头框蛋白 3（FoxP3）的控制。通过选择性剪接，人类 FoxP3 基因产生四个不同的剪接变体：全长变体（FL）和缺失每个外显子 2（∆2 变体）或 7（∆7 变体）或两个外显子缺失（∆2∆7 变体）的截断变体。它们在 Tregs 生物学中的参与及其与自身免疫性疾病的关联仍有待阐明。本工作的目的是通过剪接转换寡核苷酸在人 Tregs 中诱导单个 FoxP3 剪接变体，并监测其表型、增殖和抑制活性。我们证明多发性硬化症患者外周血中的 Tregs 优先表达截断的剪接变体，而 FL 变体是健康供体中的主要变体。表达截断 FoxP3 剪接变体的 Tregs 的抑制活性低于表达 FL 变体的 Tregs。抑制作用降低与 Treg 相关的抑制性表面分子的表达减少和细胞因子的产生有关。外显子 2 和/或 7 的缺失也降低了细胞增殖率。这项研究的结果表明 FoxP3 剪接变体与 Treg 功能和增殖之间存在关联。通过诱导 FoxP3 FL 变体来调节 Treg 抑制活性可能成为再生免疫治疗的有前途的策略。
