老年重症感染患者肺炎克雷伯菌临床分离菌株毒力因子与PBMC自噬关键蛋白表达的关系

Relationship between virulence factors in clinical isolates and expressions of key autophagy proteins in PBMCs of elderly patients with severe Klebsiella pneumoniae infection

目的探究老年重症感染患者肺炎克雷伯菌临床分离菌株毒力因子与外周血单个核细胞(PBMC)上自噬关键蛋白表达的关系。方法以2016年3月-2021年3月郑州市第九人民医院51例老年肺炎克雷伯菌感染重症患者为重症组,同期37例老年肺炎克雷伯菌感染轻症患者为轻症组,分析肺炎克雷伯菌对常用抗菌药物的耐药性。比较两组患者临床分离株毒力基因检出率及PBMC自噬关键蛋白表达。结果肺炎克雷伯菌对氨苄西林耐药,对头孢哌酮/舒巴坦、美罗培南、厄他培南、亚胺培南敏感;重症组fimH、entB、wabG检出率均高于轻症组(P<0.05);fimH基因阳性患者自噬相关基因微管相关蛋白1轻链3B(LC3B)、组蛋白去乙酰化酶6(HDAC6)蛋白表达量高于阴性患者,核因子E2相关因子2(Nrf2)蛋白表达量低于阴性患者(P<0.05);entB基因阳性者LC3B蛋白表达量高于阴性患者,Nrf2蛋白表达量低于阴性患者(P<0.05)。结论老年重症肺炎克雷伯菌感染患者存在fimH、entB、wabG基因及LC3B、HDAC6、Nrf2蛋白异常表达现象,且fimH、entB基因阳性患者的LC3B、HDAC6蛋白表达量增加,而Nrf2表达量降低。

OBJECTIVE To explore the relationship between the virulence factors in clinical isolates and the expressions of key autophagy proteins in peripheral blood mononuclear cells(PBMCs)of elderly patients with severe Klebsiella pneumoniae infection.METHODS A total of 51 elderly patients with severe K.pneumoniae infection who were treated in the Ninth People′s Hospital of Zhengzhou from Mar 2016 to Mar 2021 were assigned as the severe group,meanwhile,37 elderly patients with mild K.pneumoniae infection were chosen as the mild group.The drug resistance rates of the K.pneumoniae strains to commonly used antibiotics were analyzed.The detection rates of virulence genes in the clinical isolates and the expression levels of key autophagy proteins in PBMCs were observed and compared between the two groups of patients.RESULTS The K.pneumoniae strains were resistant to ampicillin but were sensitive to cefoperazone-sulbactam,meropenem,ertapenem and imipenem.The detection rates of fimH,entB and wabG of the severe group were higher than those of the mild group(P<0.05).The expression levels of microtubule-associated protein 1 light chain 3B(LC3B)and histone deacetylase 6(HDAC6)proteins of the fimH-positive patients were higher than those of the fimH-negative patients;the expression level of nuclear factor erythroid-derived factor 2-related factor(Nrf2)protein of the fimH-positive patients was lower than that of the fimH-negative patients(P〈0.05).The expression level of LC3B protein of the entB-positive patients was higher than that of the entB-negative patients,and the expression level of Nrf2 of the entB-positive patients was lower than that of the entB-negative patients(P<0.05).CONCLUSION The elderly patients with severe K.pneumoniae infection show abnormal expressions of fimH,entB and wabG genes as wells as LC3B,HDAC6 and Nrf2 proteins;the fimH-and entB-positive patients show the rise of expressions of LC3B and HDAC6 proteins and the decline of expression of Nrf2.