title: Recombinant TB10.4 of Mycobacterium bovis induces cytokine production in RAW264.7 macrophages through activation of the MAPK and NF-κB pathways via TLR2.
abstract: The TB10.4 antigen of Mycobacterium bovis/Mycobacterium tuberculosis induces a strong Th1 CD4+ T-cell response. Thus, it is currently under intensive study as a possible vaccine candidate. However, how TB10.4 activates innate immune cells is unclear. How TB10.4 interacts with toll-like receptors (TLRs) and signaling pathways responsible for active inflammation have also not been fully elucidated. Here, as stimulated RAW264.7 cells with recombinant TB10.4 (rTB10.4), derived from M. bovis, increased TNF-α, IL-6 and IL-12 p40 secretin in a dose-dependent manner. Blocking assays showed that TLR2-, but not TLR4-neutralizing antibody reduced expression of TNF-α, IL-6 and IL-12 p40 in RAW264.7 cells. rTB10.4 stimulation activated p38 kinase (p38) and extracellular-regulated kinase (ERK) was TLR2-dependent, whereas inhibition of p38 and ERK activity significantly reduced TNF-α, IL-6 and IL-12 p40 production. Furthermore, rTB10.4 stimulation of RAW264.7 cells resulted in TLR2-mediated activation of NF-κB and induced translocation of NF-κB p65 from the cytoplasm to the nucleus via IκBα degradation. rTB10.4-induced TNF-α, IL-6 and IL-12 p40 release was attenuated by the specific IκB phosphorylation inhibitor, BAY 11-7082. These findings indicate that the M. bovis-derived rTB10.4 induced production of TNF-α, IL-6 and IL-12 p40 involves p38, ERK and NF-κB via the TLR2 pathway.
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China. Electronic address: liushuqing1986@126.com.
authors.forename: Shuqing
authors.initials: S
authors.lastname: Liu
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Jia
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Shaohua
authors.initials: S
authors.lastname: Hou
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Gaimei
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Ting
authors.initials: T
authors.lastname: Xin
authors.affiliation: Qingdao Institute of Animal Science and Veterinary Medicine, Shandong 266000, PR China; Key Laboratory for Farm Animal Genetic Resources and Utilization of Ministry of Agriculture of China, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Hegang
authors.initials: H
authors.lastname: Li
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Yuan
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Guo
authors.affiliation: Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
authors.forename: Xintao
authors.initials: X
authors.lastname: Gao
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
authors.affiliation: Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China. Electronic address: bioclub@vip.sina.com.
authors.forename: Hongfei
authors.initials: H
authors.lastname: Zhu
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology* / Q000494:pharmacology; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism*; D004789:Enzyme Activation; D057809:HEK293 Cells; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000276:immunology; D008262:Macrophage Activation / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism; D011994:Recombinant Proteins / Q000276:immunology / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology; D051195:Toll-Like Receptor 2 / Q000502:physiology*; D015854:Up-Regulation / Q000187:drug effects / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D016207:Cytokines; D016328:NF-kappa B; D011994:Recombinant Proteins; C501710:TB10.4 antigen, Mycobacterium tuberculosis; C493486:Tlr2 protein, mouse; D051195:Toll-Like Receptor 2
keywords: Mitogen-activated protein kinase; Mycobacterium bovis; NF-kappaB pathway; TB10.4; TLR2