Hemolysin Sph2 from Leptospira interrogans amplified inflammatory response in murine macrophages J774A.1 through HMGB1
10.3760/cma.j.cn112309-20210127-00038
- VernacularTitle:问号钩端螺旋体溶血素Sph2经HMGB1放大炎症反应的研究
- Author:
Xuhong CHEN
1
;
Shuai GAO
;
Aihua SUN
;
Jie YAN
;
Xu′ai LIN
Author Information
1. 浙江大学医学院病原生物学系，杭州 310058
- Keywords:
Leptospira interrogans;
Hemolysin Sph2;
HMGB1;
Proinflammatory cytokines;
Amplification of inflammatory
- From:
Chinese Journal of Microbiology and Immunology
2021;41(8):592-597
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the possible mechanism of high mobility group box-1 (HMGB1) in amplifing inflammatory responses in Leptospira interrogans hemolysin Sph2-treated J774A.1 macrophages. Methods:Recombinant Sph2 was incubated with J774A.1 macrophages. The damage of cell membrane was detected by lactate dehydrogenase(LDH) determination; the changes of cell structure were observed by cryo-electron microscope; ELISA was used to determine the expression of HMGB1. After the commercial recombinant HMGB1 was incubated with mouse J774A.1 macrophages, the phosphorylation of NF-κB, p38-MAPK and JNK signaling pathway wsa detected by Western blot, and the expression of IL-1β, IL-6, and KC (IL-8) was detected by ELISA.Results:Recombinant hemolysin rSph2 induced significant changes in the structures of J774A.1 cells, including nucleus disappearance, cell membrane structure damage, cell lysis and membrane swelling. The yields of LDH and HMGB1 also increased significantly. Phosphorylated-NF-κB, -p38-MAPK and -JNK were increased by HMGB1. The expression of IL-1β, IL-6 and KC in J774A.1 cells was up-regulated by HMGB1 and inhibited via inhibitors of NF-κB, p38-MAPK and JNK signal pathways.Conclusions:Hemolysin rSph2 damaged the membrane of J774A.1 cells, and induced the secretion of HMGB1. Secreted-HMGB1 might induce the expression of IL-1β, IL-6 and KC in J774A.1 cells via NF-κB, p38-MAPK and JNK signal pathways, thus amplifying the inflammatory responses caused by Sph2.
