Department of Laboratory Medicine, The First Affiliated Hospital with Nanjing Medical University, No. 300 Guangzhou Road, Nanjing, 210029, Jiangsu, China.
Arch Virol. 2020 Nov;165(11):2531-2540. doi: 10.1007/s00705-020-04783-4. Epub 2020 Aug 26.
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 型（EV71）诱导的 T 淋巴细胞凋亡在手足口病（HFMD）中起重要作用，颗粒酶 B（GZMB）已被证明对这一过程至关重要。然而，GZMB 介导的 T 淋巴细胞凋亡的机制尚不清楚。在这项研究中，我们研究了转录因子和 microRNAs（miRNAs）是否参与 EV71 感染诱导的 T 淋巴细胞 GZMB 介导的凋亡。我们的研究结果表明，EV71 感染显著诱导 Jurkat 细胞（一种人 T 淋巴细胞系）凋亡，这在流式细胞术分析中得到证实。此外，EV71 增加了促凋亡 Bcl-2 相关 X（Bax）和 cleaved 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 敲低减少了细胞凋亡，并防止了 EV71 诱导的 Jurkat 细胞中 Bax、cleaved caspase 3 和 Bcl2 表达的变化，突出了 GZMB 作为 EV71 诱导凋亡的关键因素的作用。我们的研究还表明，转录因子 GATA 结合因子 1（GATA1）和特异性蛋白 1（SP1）的过表达显著增加了当该基因插入 GZMB 3'非翻译区（3'UTR）时的荧光素酶活性。GATA1/SP1 过表达诱导细胞凋亡，增加 Bax 和 cleaved caspase 3 的表达，降低 Bcl2 的表达。最后，我们的结果表明，miR-874 在 GZMB 介导的细胞凋亡中起重要作用，因为 miR-874 模拟物通过靶向其 3'UTR 降低 GZMB 的表达。总之，这些数据表明，GATA1/SP1 和 miR-874 以颗粒酶 B 依赖的方式介导 EV71 诱导的细胞凋亡。该信号通路可能为预防和治疗 HFMD 提供新的药物靶点。
