摘要
目的:探讨Rab GTP酶是否参与了对细菌脂蛋白(BLP)耐受的骨髓诱导分化巨噬细胞(BMDMs)杀菌能力增强的过程。方法:首先利用real-time PCR比较BLP耐受巨噬细胞和非耐受细胞中Rab5a、Rab5b、Rab7、Rab9、Rab9b、Rab11a、Rab11b、Rab12、Rab32和Rab34的表达变化,筛选出水平升高的Rab7分子;进一步用real-time PCR和Western blot实验证实Rab7的mRNA和蛋白表达是否在BLP耐受细胞感染大肠杆菌后继续升高;接下来用RNAi技术下调BLP耐受巨噬细胞Rab7表达,观察细胞对细菌的吞噬能力及杀灭能力的影响。结果:在检测的10个Rab GTP酶中,Rab7在BLP耐受BMDMs的mRNA水平升高,是非耐受细胞的1.4倍;进一步用real-time PCR和Western blot实验证实Rab7的mRNA和蛋白表达在BLP耐受细胞感染大肠杆菌后,随着时间延长均明显升高;下调Rab7表达不影响BLP耐受巨噬细胞对细菌的吞噬能力,但是显著降低其对细菌的杀灭能力。结论:BLP耐受通过上调巨噬细胞Rab7的表达,在增强巨噬细胞对细菌的杀灭过程中发挥重要作用。
AIM： To explore whether Rab GTPases are involved in enhanced bacterial clearance by bacterial lipoprotein（ BLP）-tolerized macrophages（ bone marrow-derived macrophages,BMDMs）. METHODS： Real-time PCR was used to compare the mRNA levels of Rab5 a,Rab5b,Rab7,Rab9,Rab9 b,Rab11a,Rab11 b,Rab12,Rab32 and Rab34 between the naive BMDMs and the BLP-tolerized BMDMs. The up-regulation of Rab7 was further confirmed in BLPtolerized BMDMs infected with E. coli by real-time PCR and Western blot. Following down-regulating the expression of Rab7 using RNA interference（ RNAi）,the bacterial uptake and intracellular bacterial killing of BLP-tolerized BMDMs treated with E. coli were detected. RESULTS： The mRNA level of Rab7 was significantly increased in BLP-tolerized BMDMs,which was 1. 4 folds as high as that in the naive BMDMs,and the mRNA and protein levels of Rab7 in BLP-tolerized BMDMs stimulated with bacteria were further confirmed to be increased. Down-regulating the expression of Rab7 had no effect on phagocytosis of BLP-tolerized BMDMs for bacteria,but the intracellular bacterial killing ability was significantly attenuated. CONCLUSION： BLP tolerance plays an important role during intracellular bacterial killing in macrophages through up-regulating the expression of Rab7.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2016年第5期900-906,共7页
Chinese Journal of Pathophysiology
基金
国家自然科学基金资助项目(No.81272149
No.81471901)
