Enterovirus 71 (EV71)-induced T lymphocyte apoptosis plays an important role in hand, foot, and mouth disease (HFMD), and granzyme B (GZMB) has been shown to be critical for this process. However, the mechanisms underlying GZMB-mediated apoptosis of T lymphocytes remain unknown. In this study, we investigated whether transcription factors and microRNAs (miRNAs) are involved in GZMB-mediated apoptosis of T lymphocytes in response to EV71 infection. Our findings indicated that EV71 infection significantly induced apoptosis in Jurkat cells, a human T lymphocytes cell line, as revealed in flow cytometric analysis. Furthermore, EV71 increased the expression of pro-apoptosis Bcl-2-associated X (Bax) and cleaved caspase 3 but decreased the expression of anti-apoptosis B-cell lymphoma protein 2 (Bcl2). GZMB knockdown decreased cell apoptosis and prevented EV71-induced changes in the expression of Bax, cleaved caspase 3, and Bcl2 in Jurkat cells, highlighting the role of GZMB as a key factor in EV71-induced apoptosis. Our study also indicated that overexpression of the transcription factors GATA binding factor 1 (GATA1) and specificity protein 1 (SP1) significantly increased luciferase activity when this gene was inserted in the GZMB 3’ untranslated region (3’UTR). GATA1/SP1 overexpression induced cell apoptosis, increased the expression of Bax and cleaved caspase 3, and decreased the expression of Bcl2. Finally, our results suggested that miR-874 plays an essential role in GZMB-mediated cell apoptosis, since an miR-874 mimic decreases the expression of GZMB by targeting its 3’UTR. Collectively, these data indicated that GATA1/SP1 and miR-874 mediate EV71-induced apoptosis in a granzyme B-dependent manner. This signaling pathway may provide a new pharmacological target for the prevention and treatment of HFMD.

肠道病毒 71 (EV71) 诱导的 T 淋巴细胞凋亡在手足口病 (HFMD) 中发挥重要作用，而颗粒酶 B (GZMB) 已被证明在此过程中至关重要。然而，GZMB 介导的 T 淋巴细胞凋亡的机制仍不清楚。在这项研究中，我们研究了转录因子和 microRNA (miRNA) 是否参与 GZMB 介导的 EV71 感染引起的 T 淋巴细胞凋亡。我们的研究结果表明，流式细胞术分析表明，EV71 感染显着诱导 Jurkat 细胞（一种人类 T 淋巴细胞细胞系）凋亡。此外，EV71 增加了促凋亡 Bcl-2 相关 X (Bax) 和裂解 caspase 3 的表达，但降低了抗凋亡 B 细胞淋巴瘤蛋白 2 (Bcl2) 的表达。 GZMB 敲低可减少细胞凋亡，并阻止 EV71 诱导的 Jurkat 细胞中 Bax、裂解型 caspase 3 和 Bcl2 表达的变化，这凸显了 GZMB 作为 EV71 诱导细胞凋亡的关键因素的作用。我们的研究还表明，当转录因子 GATA 结合因子 1 (GATA1) 和特异性蛋白 1 (SP1) 插入 GZMB 3' 非翻译区 (3'UTR) 时，该基因的过度表达会显着增加荧光素酶活性。 GATA1/SP1过表达诱导细胞凋亡，增加Bax和cleaved caspase 3的表达，并减少Bcl2的表达。最后，我们的结果表明，miR-874 在 GZMB 介导的细胞凋亡中发挥重要作用，因为 miR-874 模拟物通过靶向其 3'UTR 来降低 GZMB 的表达。总的来说，这些数据表明 GATA1/SP1 和 miR-874 以颗粒酶 B 依赖性方式介导 EV71 诱导的细胞凋亡。 该信号通路可能为手足口病的预防和治疗提供新的药理学靶点。