We investigated the role of miR-522-3p in thymoma-associated myasthenia gravis (TAMG), and the mechanism of action in T cells. The miR-522-3p expression in normal serum, non-thymoma MG patient serum and TAMG patient serum and tissues was detected by quantitative real-time PCR (qRT-PCR), respectively. We assessed miR-522-3p expression in Jurkat cells and human CD4⁺ T cells after activation by anti-CD3 and anti-CD28 using qRT-PCR. The viability, proliferation, cycle distribution and the levels of CD25, CD69, interleukin-2 (IL-2) and IL-10 in transfected Jurkat cells were detected by Cell counting kit-8, 5-ethynyl-2′-deoxyuridine (EdU), flow cytometry, qRT-PCR, respectively. Targeting relationships of miR-522-3p and SLC31A1 were predicted and validated by bioinformatics analysis and dual-luciferase reporter. The viability, proliferation, cycle distribution and the levels of SLC31A1, CD25, CD69, IL-2 and IL-10 in transfected Jurkat cells were detected by above methods and western blot. The miR-522-3p expression was declined in TAMG and activated T cells. MiR-522-3p inhibitor promoted cell viability, EdU positive cells, cycle progression, and the level of CD25, CD69, IL-2 and IL-10 in Jurkat cells, while the effect of miR-522-3p mimic was the opposite. SLC31A1 was targeted by miR-522-3p, and miR-522-3p inhibited SLC31A1 expression. Overexpressed SLC31A1 reversed the inhibitory effects of miR-522-3p mimic on cell viability, EdU positive cell, cycle progression, and the levels of IL-2 and IL-10 in transfected Jurkat cells. MiR-522-3p expression was down-regulated in TAMG, and miR-522-3p inhibited proliferation and activation by regulating SLC31A1 expression in T cells.

我们研究了 miR-522-3p 在胸腺瘤相关重症肌无力 (TAMG) 中的作用，以及在 T 细胞中的作用机制。分别通过定量实时PCR（qRT-PCR）检测正常血清、非胸腺瘤MG患者血清和TAMG患者血清和组织中miR-522-3p的表达。我们评估了 miR-522-3p 在 Jurkat 细胞和人 CD4 ^{+中的表达}使用 qRT-PCR 被抗 CD3 和抗 CD28 激活后的 T 细胞。细胞计数试剂盒8, 5-ethynyl-2'-deoxyuridine (EdU) 检测转染的Jurkat细胞的活力、增殖、周期分布及CD25、CD69、白细胞介素2 (IL-2)和IL-10的水平)、流式细胞术、qRT-PCR。通过生物信息学分析和双荧光素酶报告基因预测和验证 miR-522-3p 和 SLC31A1 的靶向关系。通过上述方法和western blot检测转染的Jurkat细胞的活力、增殖、周期分布及SLC31A1、CD25、CD69、IL-2和IL-10的水平。TAMG 和活化的 T 细胞中 miR-522-3p 表达下降。MiR-522-3p 抑制剂促进细胞活力、EdU 阳性细胞、周期进展以及 Jurkat 细胞中 CD25、CD69、IL-2 和 IL-10 的水平，而 miR-522-3p 模拟的效果则相反。SLC31A1 被 miR-522-3p 靶向，miR-522-3p 抑制 SLC31A1 表达。过表达的 SLC31A1 逆转了 miR-522-3p 模拟物对转染的 Jurkat 细胞中细胞活力、EdU 阳性细胞、周期进展以及 IL-2 和 IL-10 水平的抑制作用。TAMG 中 MiR-522-3p 表达下调，miR-522-3p 通过调节 T 细胞中 SLC31A1 的表达来抑制增殖和活化。