Department of Microbiology and Immunology, Medical College, Jinan University, Guangzhou, Guangdong Province, 510632, People's Republic of China.
Department of Epidemiology and Health statistics, Medical College, Jinan University, Guangzhou, Guangdong Province, 510632, People's Republic of China.
Parasit Vectors. 2018 May 18;11(1):305. doi: 10.1186/s13071-018-2837-1.
Acute T-lymphocyte leukaemia is a form of haematological malignancy with abnormal activation of NF-κB pathway, which results in high expression of A20 and ABIN1, which constitute a negative feedback mechanism for the regulation of NF-κB activation. Clinical studies have found that acute T-lymphocyte leukaemia patients are susceptible to Toxoplasma gondii infection; however, the effect of T. gondii on the proliferation and apoptosis of human leukaemia T-cells remains unclear. Here, we used the T. gondii ME-49 strain to infect human leukaemia T-cell lines Jurkat and Molt-4, to explore the effect of T. gondii on proliferation and apoptosis, which is mediated by NF-κB in human leukaemia T-cells.
The Tunel assay was used to detect cell apoptosis. Cell Counting Kit-8 was used to detect cell proliferation viability. The apoptosis level and the expression level of NF-κB related proteins in human leukaemia T-cells were detected by flow cytometry and Western blotting.
Western blotting analyses revealed that the T. gondii ME-49 strain increased the expression of A20 and decreased both ABIN1 expression and NF-κB p65 phosphorylation. By constructing a lentiviral-mediated shRNA to knockdown the A20 gene in Jurkat T-cells and Molt-4 T-cells, the apoptosis levels of the two cell lines decreased after T. gondii ME-49 infection, and levels of NF-κB p65 phosphorylation and ABIN1 were higher than in the non-konckdown group. After knockingdown ABIN1 gene expression by constructing the lentiviral-mediated shRNA and transfecting the recombinant expression plasmid containing the ABIN1 gene into two cell lines, apoptosis levels and cleaved caspase-8 expression increased or decreased in response to T. gondii ME-49 infection, respectively.
Our data suggest that ABIN1 protects human leukaemia T-cells by allowing them to resist the apoptosis induced by T. gondii ME-49 and that the T. gondii ME-49 strain induces the apoptosis of human leukaemia T-cells via A20-mediated downregulation of ABIN1 expression.
急性 T 淋巴细胞白血病是一种血液恶性肿瘤，其 NF-κB 通路异常激活，导致 A20 和 ABIN1 的高表达，构成了 NF-κB 激活调节的负反馈机制。临床研究发现，急性 T 淋巴细胞白血病患者易感染刚地弓形虫；然而，刚地弓形虫对人白血病 T 细胞增殖和凋亡的影响尚不清楚。在这里，我们使用刚地弓形虫 ME-49 株感染人白血病 T 细胞系 Jurkat 和 Molt-4，探讨刚地弓形虫通过 NF-κB 对人白血病 T 细胞增殖和凋亡的影响。
使用 Tunel 检测法检测细胞凋亡。使用细胞计数试剂盒-8 检测细胞增殖活力。通过流式细胞术和 Western blot 检测人白血病 T 细胞的凋亡水平和 NF-κB 相关蛋白的表达水平。
Western blot 分析显示，刚地弓形虫 ME-49 株增加了 A20 的表达，降低了 ABIN1 的表达和 NF-κB p65 的磷酸化。通过构建慢病毒介导的 shRNA 敲低 Jurkat T 细胞和 Molt-4 T 细胞中的 A20 基因，在刚地弓形虫 ME-49 感染后，这两种细胞系的凋亡水平下降，NF-κB p65 磷酸化和 ABIN1 的水平高于非敲低组。通过构建慢病毒介导的 shRNA 敲低 ABIN1 基因表达并将含有 ABIN1 基因的重组表达质粒转染到两种细胞系中，在刚地弓形虫 ME-49 感染后，凋亡水平和 cleaved caspase-8 的表达分别增加或减少。
我们的数据表明，ABIN1 通过允许人白血病 T 细胞抵抗刚地弓形虫 ME-49 诱导的凋亡来保护人白血病 T 细胞，而刚地弓形虫 ME-49 株通过 A20 介导的 ABIN1 表达下调诱导人白血病 T 细胞凋亡。
