实用医学杂志 ›› 2022, Vol. 38 ›› Issue (1): 45-50.doi: 10.3969/j.issn.1006⁃5725.2022.01.009

• 基础研究 • 上一篇    下一篇

结核分枝杆菌PknG炎症免疫应答抑制内毒素介导的巨噬细胞

彭章丽 沈瑶 付雪峰   

  1. 遵义医科大学附属医院呼吸与危重症医学科结核病区(贵州遵义563000)

  • 出版日期:2022-01-10 发布日期:2022-01-10
  • 基金资助:
    国家自然科学基金地区基金(编号:81960004);贵州省科技计划项目课题(编号:黔科合基础⁃ZK[2021]一般 348);遵义市科技局课题(编号:遵市科合 HZ 字 2019(70)号);遵义医学院硕士启动基金(编号:2015(009))

Mycobacterium tuberculosis PknG inhibits endotoxin ⁃mediated inflammatory immune response in macro⁃ phages

PENG Zhangli,SHEN Yao,FU Xuefeng.   

  1. Tuberculosis DivisionSecond Department of Respiratory and Critical Care Medicinethe Affiliated Hospital of Zunyi Medical UniversityZunyi 563000China
  • Online:2022-01-10 Published:2022-01-10

摘要:

目的 利用原核表达系统表达、纯化结核分枝杆菌分泌蛋白 PknG,并探讨 PknG 在炎症免 疫应答中的作用。方法 NCBI 数据库中获取结核分枝杆菌 PknG 全基因组序列,高保真 PCR 扩增结核 分枝杆菌 PknG 全基因序列,构建 PknG⁃pET28a 融合表达质粒,IPTG 诱导表达 PknG 蛋白,镍柱及不同浓度 咪唑纯化及透析 PknG 蛋白,SDS⁃PAGE western blot 验证 PknG 蛋白的表达,脂多糖(LPS)处理巨噬细胞 0、12 24 h,通过 Real⁃time PCR ELISA 方法检测促炎细胞因子 TNF⁃α IL⁃6 的表达。结果 成功诱 导表达及纯化结核分枝杆菌 PknG 蛋白,PknG 抑制 LPS 处理的巨噬细胞促炎细胞因子 TNF⁃α IL⁃6 表达。结论 结核分枝杆菌 PknG 蛋白抑制 LPS 诱导巨噬细胞促炎细胞因子 TNF⁃α IL⁃6 的表达,可作为结核分枝杆菌感染合并脓毒血症过程中治疗的一个潜在靶点。

关键词: 结核分枝杆菌, 内毒素, 巨噬细胞, PknG, 炎症

Abstract:

Objective To express and purify the secreted protein PknG of Mycobacterium tuberculosis through prokaryotic expression system and further investigate its role in the inflammatory immune response. Methods The whole genome sequence of Mycobacterium tuberculosis PknG was obtained from the NCBI database. After the PknG was amplified by high fidelity PCR and the PknG ⁃ pET28a plasmid was constructed,the PknG protein expression was induced by IPTG,the PknG protein was purified by nickel columns and imidazole at differ⁃ ent concentrations and finally the expression of PknG protein was verified by SDS⁃PAGE and western blot. After the macrophages were treated with LPS at 0 h,12 h and 24 h,the expression of pro ⁃inflammatory cytokines TNF ⁃ α and IL⁃6 was detected by Real⁃time PCR and ELISA. Results PknG protein was successfully induced and puri⁃ fied. PknG inhibited the expression of pro⁃inflammatory cytokines TNF⁃α and IL⁃6 in LPS⁃induced macrophages. Conclusion PknG of Mycobacterium tuberculosiscan inhibit the expression of pro⁃inflammatory cytokines TNF⁃ α and IL⁃6 in macrophages. Therefore,it may be related to the potential target for the treatment of Mycobacterium tuberculosis infection in the course of sepsis.

Key words:

Mycobacterium tuberculosis, endotoxin, macrophage, PknG, inflammation