title: Critical role of TRIF and MyD88 in Mycobacterium tuberculosis Hsp70-mediated activation of dendritic cells.
abstract: As a potent immune regulator, heat shock protein 70 derived from Mycobacterium tuberculosis (Mtb Hsp70) has adjuvant effect and activates immune cells such as macrophages and dendritic cells (DCs). Although Toll-like receptors (TLRs) are known to involve in DCs activation by Mtb Hsp70, there is still a controversy and the underlying mechanism is not well understood. In this study, we examined whether TRIF and MyD88, the core adaptor molecules for TLRs signaling, regulate Mtb Hsp70-induced DCs activation. Although Mtb Hsp70 produced substantial level of cytokines (IL-6, IL-12p40, and TNF-α) in TRIF-deficient DCs in a dose-dependent manner, each level was significantly lower than that in WT cells. The cytokines production was almost abolished in MyD88-deficient DCs. Consistent with cytokine results, Mtb Hsp70-induced activation of NF-κB and MAPKs was also impaired in both TRIF- and MyD88-deficient DCs, as compared with WT cells. Inhibitor assay revealed that NF-κB, ERK, and JNK, but not p38, regulate Mtb Hsp70-induced production of cytokines. In addition, the up-regulation of co-stimulatory molecules and MHC class II was mostly TRIF-dependent in DCs in response Mtb Hsp70, whereas MyD88 was only partially involved. Finally, mixed leukocytes reaction (MLR) assay revealed that both TRIF and MyD88 are critical for DCs ability promoted by Mtb Hsp70 to differentiate naïve T cells into effector T cells of producing IFN-γ. Our findings suggest that both TRIF and MyD88 are essential for the activation and maturation of DCs in response to Mtb Hsp70.
authors.affiliation: Laboratory Animal Medicine, College of Veterinary Medicine, Seoul University, Seoul 151-742, Republic of Korea.
authors.forename: Tae-Hyoun
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Department of Microbiology and Institute for Immunology and Immunological Diseases, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea.
authors.forename: Sung Jae
authors.initials: SJ
authors.lastname: Shin
authors.affiliation: Department of and Immunology, Lab of Dendritic Cell Differentiation & Regulation, School of Medicine, Konkuk University, 268 Chungwondae-ro, Chungju 380-701, Republic of Korea.
authors.forename: Yeong-Min
authors.initials: YM
authors.lastname: Park
authors.affiliation: Department of and Immunology, Lab of Dendritic Cell Differentiation & Regulation, School of Medicine, Konkuk University, 268 Chungwondae-ro, Chungju 380-701, Republic of Korea.
authors.forename: In Duk
authors.initials: ID
authors.lastname: Jung
authors.affiliation: Department of Bio and Brain Engineering, KAIST, Daejeon 305-701, Republic of Korea.
authors.forename: Seung-Wook
authors.initials: SW
authors.lastname: Ryu
authors.affiliation: Department of Biochemistry, College of Medicine, Konyang University, Daejeon 302-718, Republic of Korea.
authors.forename: Dong-Jae
authors.initials: DJ
authors.lastname: Kim
authors.affiliation: Laboratory Animal Medicine, College of Veterinary Medicine, Seoul University, Seoul 151-742, Republic of Korea.
authors.forename: Jae-Hak
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Laboratory Animal Medicine, College of Veterinary Medicine, Chonnam National University, Gwangju 500-757, Republic of Korea. Electronic address: jonpark@jnu.ac.kr.
authors.forename: Jong-Hwan
authors.initials: JH
authors.lastname: Park
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000172:deficiency / Q000235:genetics / Q000276:immunology*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D001854:Bone Marrow Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects / Q000276:immunology; D002478:Cells, Cultured; D018920:Coculture Techniques; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism; D007959:Lymphocyte Culture Test, Mixed; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009169:Mycobacterium tuberculosis / Q000276:immunology / Q000378:metabolism; D053594:Myeloid Differentiation Factor 88 / Q000172:deficiency / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism
chemical_list: D033942:Adaptor Proteins, Vesicular Transport; D001426:Bacterial Proteins; D016207:Cytokines; D018840:HSP70 Heat-Shock Proteins; D007371:Interferon-gamma; D053594:Myeloid Differentiation Factor 88; D011994:Recombinant Proteins; C507780:Myd88 protein, mouse; C476286:Ticam1 protein, mouse
keywords: Dendritic cells; Heat shock protein 70 (Hsp70); MyD88; Mycobacterium tuberculosis; TRIF