金黄色葡萄球菌α-溶血素突变体H35A抑制α-溶血素的细胞毒性

Staphylococcus aureus α-hemolysin mutant H35A inhibit cytotoxicity of wild α-hemolysin

目的:研究金黄色葡萄球菌α-溶血素(α-hemolysin,Hla)突变体H35A在人外周血单个核细胞(human peripheral blood mononuclear cells,h PBMC)和THP-1巨噬细胞中对于野生型Hla毒性作用的影响。方法:H35A与Hla共同作用于h PBMC和THP-1巨噬细胞,实时荧光定量PCR检测细胞中白介素(interleukin,IL)-1β、IL-6、肿瘤坏死因子(tumor necrosis factor,TNF)-α等炎症因子的m RNA转录水平差异,台盼蓝染色计算THP-1巨噬细胞存活率。结果:预孵育突变体H35A 1 h的h PBMC和THP-1巨噬细胞,经Hla刺激产生IL-1、IL-6、TNF-α的m RNA转录水平显著降低;台盼蓝染色计数发现,H35A与Hla共同作用的THP-1巨噬细胞存活率显著高于Hla单独处理组。结论:突变体H35A可抑制野生型Hla对于h PBMC和巨噬细胞的毒性作用,为金黄色葡萄球菌早期感染防治药物的研发提供了更多选择。

Objective：To study the effect of Staphylococcus aureus α-hemolysin mutant H35 A on the wild type α-hemolysin（Hla）toxicity in human periphery blood mononuclear cells（h PBMC） and THP-1 macrophages. Methods：h PBMC and THP-1 macrophages were stimulated with both H35 A and Hla. The transcriptions of interleukin-1β（IL-1β）,interleukin-6（IL-6）,tumor necrosis factor-α（TNF-α） m RNA in h PBMC and THP-1 macrophages were assayed by real-time Q-PCR. The survival percentage of THP-1macrophages treated with Hla and H35 A was calculated with Trypan blue staining. Results：The transcriptions of IL-1,IL-6 and TNF-α m RNA in h PBMC and THP-1 macrophages treated with H35 A mutant were significantly decreased upon stimulation with Hla. The survival percentage of THP-1 macrophages treated with Hla and H35 A was significantly increased. Conclusion：H35A mutant can inhibit the toxic effect of Hla on human monocytes and macrophages,and it is expected to be a therapeutic drug used in the early stage of Staphylococcus aureus infection.