title: A subunit vaccine based on rH-NS induces protection against Mycobacterium tuberculosis infection by inducing the Th1 immune response and activating macrophages.
abstract: Mycobacterium tuberculosis (Mtb) is a Gram-positive pathogen which causes tuberculosis in both animals and humans. All tested rH-NS formulations induced a specific Th1 response, as indicated by increased production of interferon γ (IFN-γ) and interleukin 2 (IL-2) by lymphocytes in the spleen of mice which were immunized with rH-NS alone or with rH-NS and the adjuvant cyclic GMP-AMP (cGAMP). Serum from mice immunized with rH-NS with or without adjuvant also had higher levels of IL-12p40 and TNF-α, compared with those from control mice immunized with phosphate-buffered saline. Both vaccines increased protective efficacy in mice which were challenged with Mtb H37Rv, as measured by reduced relative CFU counts in the lungs. We found that rH-NS induced the production of TNF-α, IL-6, and IL-12p40, which relied on the activation of mitogen-activated protein kinases by stimulating the rapid phosphorylation of ERK1/2, p38, and JNK, and on the activation of transcription factor NF-κB in macrophages. Additionally, we also found that rH-NS could interact with TLR2 but not TLR4 in pull-down assays. The rH-NS-induced cytokine production from TLR2-silenced RAW264.7 cells was lower than that from BALB/c macrophages. Prolonged exposure (>24 h) of RAW264.7 cells to rH-NS resulted in a significant enhancement in IFN-γ-induced MHC II expression, which was not found in shTLR2-treated RAW264.7 cells. These results suggest that rH-NS is a TLR2 agonist which induces the production of cytokines by macrophages and up-regulates macrophage function.
authors: State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China.
authors: Yuan
authors: Y
authors: Liu
authors: National Clinical Laboratory on Tuberculosis, Beijing Key Laboratory on Drug-Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing 101149, China.
authors: Suting
authors: S
authors: Chen
authors: State Key Laboratory of Natural and Biomimetic Drugs, Peking Universtiy Health Science Center, Beijing 100191, China.
authors: Bowen
authors: B
authors: Pan
authors: State Key Laboratory of Natural and Biomimetic Drugs, Peking Universtiy Health Science Center, Beijing 100191, China.
authors: Zhu
authors: Z
authors: Guan
authors: State Key Laboratory of Natural and Biomimetic Drugs, Peking Universtiy Health Science Center, Beijing 100191, China.
authors: Zhenjun
authors: Z
authors: Yang
authors: State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China.
authors: Linfei
authors: L
authors: Duan
authors: State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China hcai@pku.edu.cn.
authors: Hong
authors: H
authors: Cai
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology*; D015153:Blotting, Western; D002460:Cell Line; D016207:Cytokines / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000276:immunology*; D057809:HEK293 Cells; D054884:Host-Pathogen Interactions / Q000276:immunology; D006801:Humans; D007114:Immunization / Q000379:methods; D008262:Macrophage Activation / Q000276:immunology; D008264:Macrophages / Q000276:immunology* / Q000378:metabolism; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D020928:Mitogen-Activated Protein Kinases / Q000276:immunology / Q000378:metabolism; D009169:Mycobacterium tuberculosis / Q000276:immunology* / Q000502:physiology; D010766:Phosphorylation / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018417:Th1 Cells / Q000276:immunology* / Q000378:metabolism; D051195:Toll-Like Receptor 2 / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D014376:Tuberculosis / Q000276:immunology* / Q000382:microbiology; D022223:Vaccines, Subunit / Q000235:genetics / Q000276:immunology
chemical_list: D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D016207:Cytokines; D004268:DNA-Binding Proteins; C031908:H-NS protein, bacteria; C493486:Tlr2 protein, mouse; D051195:Toll-Like Receptor 2; D022223:Vaccines, Subunit; D020928:Mitogen-Activated Protein Kinases
keywords: APC function; TLR2; adjuvant; cytokines; rH-NS antigen; tuberculosis; vaccines