title: Correlation of Surface Toll-Like Receptor 9 Expression with IL-17 Production in Neutrophils during Septic Peritonitis in Mice Induced by E. coli.
abstract: IL-17 is a proinflammatory cytokine produced by various immune cells. Polymorphonuclear neutrophils (PMNs) are the first line of defense in bacterial infection and express surface Toll-like receptor 9 (sTLR9). To study the relationship of sTLR9 and IL-17 in PMNs during bacterial infection, we infected mice with E. coli intraperitoneally to establish a septic peritonitis model for studying the PMNs response in peritoneal cavity. We found that PMNs and some of "giant cells" were massively accumulated in the peritoneal cavity of mice with fatal septic peritonitis induced by E. coli. Kinetically, the CD11b(+) PMNs were increased from 20-40% at 18 hours to >80% at 72 hours after infection. After E. coli infection, sTLR9 expression on CD11b(+) and CD11b(-) PMNs and macrophages in the PLCs were increased at early stage and deceased at late stage; IL-17 expression was also increased in CD11b(+) PMNs, CD11b(-) PMNs, macrophages, and CD3(+) T cells. Using experiments of in vitro blockage, qRT-PCR and cell sorting, we confirmed that PMNs in the PLCs did increase their IL-17 expression during E. coli infection. Interestingly, sTLR9(-)CD11b(+)Ly6G(+) PMNs, not sTLR9(+)CD11b(+)Ly6G(+) PMNs, were found to be able to increase their IL-17 expression. Together, the data may help understand novel roles of PMNs in septic peritonitis.
authors.affiliation: Department of Molecular Biology in College of Basic Medical Sciences and Institute of Pediatrics in First Hospital, Jilin University, Changchun 130021, China; Department of Endodontics, School and Hospital of Stomatology, Jilin University, Changchun 130021, China.
authors.forename: Yunjia
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Department of Immunology in College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
authors.forename: Li
authors.identifier: 0000-0002-1875-0606
authors.initials: L
authors.lastname: Hua
authors.affiliation: Department of Endodontics, School and Hospital of Stomatology, Jilin University, Changchun 130021, China; Department of Immunology in College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
authors.forename: Xiuping
authors.identifier: 0000-0002-9891-004X
authors.initials: X
authors.lastname: Meng
authors.affiliation: Department of Molecular Biology in College of Basic Medical Sciences and Institute of Pediatrics in First Hospital, Jilin University, Changchun 130021, China.
authors.forename: Yue
authors.identifier: 0000-0002-5629-7638
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Department of Immunology in College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Hao
authors.affiliation: Department of Molecular Biology in College of Basic Medical Sciences and Institute of Pediatrics in First Hospital, Jilin University, Changchun 130021, China.
authors.forename: Sheng
authors.identifier: 0000-0002-5928-3266
authors.initials: S
authors.lastname: Guo
authors.affiliation: Department of Immunology in College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
authors.forename: Peiyan
authors.initials: P
authors.lastname: Zhao
authors.affiliation: Department of Molecular Biology in College of Basic Medical Sciences and Institute of Pediatrics in First Hospital, Jilin University, Changchun 130021, China.
authors.forename: Luowei
authors.identifier: 0000-0002-6588-0542
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Immunology in College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
authors.forename: Boqi
authors.identifier: 0000-0003-3927-7165
authors.initials: B
authors.lastname: Dong
authors.affiliation: Department of Immunology in College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
authors.forename: Yongli
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Department of Molecular Biology in College of Basic Medical Sciences and Institute of Pediatrics in First Hospital, Jilin University, Changchun 130021, China.
authors.forename: Liying
authors.initials: L
authors.lastname: Wang
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000472:pathogenicity*; D005260:Female; D005434:Flow Cytometry; D020381:Interleukin-17 / Q000378:metabolism*; D051379:Mice; D008813:Mice, Inbred ICR; D009504:Neutrophils / Q000378:metabolism*; D010533:Peritoneal Lavage; D010538:Peritonitis / Q000378:metabolism* / Q000382:microbiology*; D051217:Toll-Like Receptor 9 / Q000378:metabolism*
chemical_list: D020381:Interleukin-17; D051217:Toll-Like Receptor 9