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Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis (Mtb) infection, with the highest single-cause mortality. Monocarboxylate transporter 4 (Mct4) transports intracellular lactate outside, but its role in regulating host immune response against Mtb infection remains unknown. Mct4 expression was upregulated in Mtb-infected macrophages and in patients with TB. Mct4 silencing/deficiency significantly decreased Mtb survival in macrophages and in lungs and spleens of mice, while Mct4 overexpression facilitated Mtb survival in macrophages. Furthermore, Mct4 promoted intracellular lactate transport, nuclear factor κB (NF-κB) p65 activation, and interleukin-10 (IL-10) production upon Mtb infection. Mechanistically, IL-10 silencing and IL-10-neutralizing antibody blocked Mct4 overexpressing increased Mtb survival. Replenishing lactate and NF-κB p65 inhibitor JSH23 treatment could inhibit Mct4 overexpressing increased NF-κB p65 activation, IL-10 production, and Mtb survival in macrophages. This study demonstrates that Mct4 promotes Mtb survival through restricting intracellular lactate accumulation to promote NF-κB p65-mediated IL-10 production and suggests Mct4-NF-κB p65-IL-10 axis a potential target for TB treatment.
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Ubiquitin-specific peptidase 25 (USP25) is one of the best-characterized deubiquitinating enzymes and plays a vital regulatory role in various biological processes, especially in cancer development and immune regulation. However, the exact role of USP25 and its underlying mechanisms in macrophage activation and immunogenicity during Mycobacterium tuberculosis infection remain unclear. In this study, we found that M tuberculosis infection induced USP25 expression in human and mouse macrophages. In particular, USP25 expression is elevated in multiple cell types, especially monocytes, in patients with tuberculosis. Additionally, USP25 deficiency in macrophages and mice resulted in compromised immunity against M tuberculosis infection, accompanied by reduced expressions of various proinflammatory cytokines and chemokines. Mechanistically, USP25 in macrophages promoted the activation of the ERK signaling pathway through deubiquitination and stabilization of B-Raf and C-Raf. These findings collectively suggest the critical roles of USP25 in M tuberculosis infection and its potential as a therapeutic target.
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Tuberculosis (TB) is still an urgent global public health problem. Notably, mucosal-associated invariant T (MAIT) cells play an important role in early anti-TB immune response. Targeted control of them may be an effective method to improve vaccine efficacy and TB treatment. However, the biology and signal regulation mechanisms of MAIT cells in TB patients are still poorly understood. Previous studies have been limited by the lack of reagents to specifically identify MAIT cells. In addition, the use of alternative markers may subsume non-MAIT cell into MAIT cell populations. In this study, the human MR1 tetramer which can specifically identify MAIT cells was used to further explore the effect and mechanism of MAIT cells in anti-TB immune response. Our results showed that the tetramer+ MAIT cells in peripheral blood of TB patients were mainly CD8+ or CD4-CD8- cells, and very few were CD4+ cells. After BCG infecting autologous antigen-presenting cells, MAIT cells in patients produced significantly higher levels of cytokines, lysis and proliferation compared with healthy controls. After suppression of mTORC1 by the mTORC1-specific inhibitor rapamycin, the immune response of MAIT cells in patients was significantly reduced. This study demonstrates that peripheral blood tetramer+ MAIT cells from TB patients have significant anti-TB immune effect, which is regulated by mTORC1. This could provide ideas and potential therapeutic targets for the development of novel anti-TB immunotherapy.
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OBJECTIVES AND DESIGN: As an interferon-inducible protein, Viperin has broad-spectrum antiviral effects and regulation of host immune responses. We aim to investigate how Viperin regulates interferon-γ (IFN-γ) production in macrophages to control Mycobacterium tuberculosis (Mtb) infection. METHODS: We use Viperin deficient bone-marrow-derived macrophage (BMDM) to investigate the effects and machines of Viperin on Mtb infection. RESULTS: Viperin inhibited IFN-γ production in macrophages and in the lung of mice to promote Mtb survival. Further insight into the mechanisms of Viperin-mediated regulation of IFN-γ production revealed the role of TANK-binding kinase 1 (TBK1), the TAK1-dependent inhibition of NF-kappa B kinase-epsilon (IKKε), and interferon regulatory factor 3 (IRF3). Inhibition of the TBK1-IKKε-IRF3 axis restored IFN-γ production reduced by Viperin knockout in BMDM and suppressed intracellular Mtb survival. Moreover, Viperin deficiency activated the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway, which promoted IFN-γ production and inhibited Mtb infection in BMDM. Additionally, a combination of the anti-TB drug INH treatment in the absence of Viperin resulted in further IFN-γ production and anti-TB effect. CONCLUSIONS: This study highlights the involvement of TBK1-IKKε-IRF3 axis and JAK-STAT signaling pathways in Viperin-suppressed IFN-γ production in Mtb infected macrophages, and identifies a novel mechanism of Viperin on negatively regulating host immune response to Mtb infection.
Assuntos
Fator Regulador 3 de Interferon , Interferon gama , Macrófagos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis , Proteínas Serina-Treonina Quinases , Proteínas , Transdução de Sinais , Animais , Interferon gama/metabolismo , Interferon gama/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Mycobacterium tuberculosis/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Fator Regulador 3 de Interferon/metabolismo , Camundongos , Proteínas/genética , Proteínas/metabolismo , Quinase I-kappa B/metabolismo , Janus Quinases/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Camundongos Knockout , Tuberculose/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Proteína ViperinaRESUMO
Tuberculosis, caused by Mycobacterium tuberculosis (Mtb), remains a global health crisis with substantial morbidity and mortality rates. Type II alveolar epithelial cells (AEC-II) play a critical role in the pulmonary immune response against Mtb infection by secreting effector molecules such as antimicrobial peptides (AMPs). Here, human ß-defensin 1 (hBD1), an important AMP produced by AEC-II, has been demonstrated to exert potent anti-tuberculosis activity. HBD1 overexpression effectively inhibited Mtb proliferation in AEC-II, while mice lacking hBD1 exhibited susceptibility to Mtb and increased lung tissue inflammation. Mechanistically, in A549 cells infected with Mtb, STAT1 negatively regulated hBD1 transcription, while CEBPB was the primary transcription factor upregulating hBD1 expression. Furthermore, we revealed that the ERK1/2 signaling pathway activated by Mtb infection led to CEBPB phosphorylation and nuclear translocation, which subsequently promoted hBD1 expression. Our findings suggest that the ERK1/2-CEBPB-hBD1 regulatory axis can be a potential therapeutic target for anti-tuberculosis therapy aimed at enhancing the immune response of AEC-II cells.
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Mycobacterium tuberculosis , Tuberculose , beta-Defensinas , Animais , Humanos , Camundongos , Células Epiteliais Alveolares , beta-Defensinas/genética , beta-Defensinas/farmacologia , Proteína beta Intensificadora de Ligação a CCAAT/genética , Células Epiteliais , Sistema de Sinalização das MAP Quinases , Tuberculose/metabolismoRESUMO
Tuberculosis has the highest mortality rate worldwide for a chronic infectious disease caused by a single pathogen. RNA-binding proteins (RBPs) are involved in autophagy - a key defense mechanism against Mycobacterium tuberculosis (M. tuberculosis) infection - by modulating RNA stability and forming intricate regulatory networks. However, the functions of host RBPs during M. tuberculosis infection remain relatively unexplored. Zinc finger NFX1-type containing 1 (ZNFX1), a conserved RBP critically involved in immune deficiency diseases and mycobacterial infections, is significantly upregulated in M. tuberculosis-infected macrophages. Here, we aimed to explore the immunoregulatory functions of ZNFX1 during M. tuberculosis infection. We observed that Znfx1 knockout markedly compromised the multifaceted immune responses mediated by macrophages. This compromise resulted in reduced phagocytosis, suppressed macrophage activation, increased M. tuberculosis burden, progressive lung tissue injury, and chronic inflammation in M. tuberculosis-infected mice. Mechanistic investigations revealed that the absence of ZNFX1 inhibited autophagy, consequently mediating immune suppression. ZNFX1 critically maintained AMPK-regulated autophagic flux by stabilizing protein kinase AMP-activated catalytic subunit alpha 2 mRNA, which encodes a key catalytic α subunit of AMPK, through its zinc finger region. This process contributed to M. tuberculosis growth suppression. These findings reveal a function of ZNFX1 in establishing anti-M. tuberculosis immune responses, enhancing our understanding of the roles of RBPs in tuberculosis immunity and providing a promising approach to bolster antituberculosis immunotherapy.
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Mycobacterium tuberculosis , Tuberculose , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/genética , Macrófagos/metabolismoRESUMO
Innate immune signaling in macrophages during viral infection is regulated by ISGylation, the covalent attachment of the ubiquitin-like protein interferon-stimulated gene 15 (ISG15) to protein targets. Here, we explored the role of ISGylation in the macrophage response to infection with Mycobacterium tuberculosis. In human and mouse macrophages, the E3 ubiquitin ligases HERC5 and mHERC6, respectively, mediated the ISGylation of the phosphatase PTEN, which promoted its degradation. The decreased abundance of PTEN led to an increase in the activity of the PI3K-AKT signaling pathway, which stimulated the synthesis of proinflammatory cytokines. Bacterial growth was increased in culture and in vivo when human or mouse macrophages were deficient in the major E3 ISG15 ligase. The findings expand the role of ISGylation in macrophages to antibacterial immunity and suggest that HERC5 signaling may be a candidate target for adjunct host-directed therapy in patients with tuberculosis.
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Fosfatidilinositol 3-Quinases , Ubiquitina-Proteína Ligases , Animais , Humanos , Camundongos , Antibacterianos , Citocinas/metabolismo , Interferons , Peptídeos e Proteínas de Sinalização Intracelular/genética , PTEN Fosfo-Hidrolase/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/metabolismoRESUMO
OBJECTIVE: Tuberculosis is the leading killer among the chronic single-source infectious diseases. Mycobacterium tuberculosis can induce necrotic-dominant multiple modes of cell death in macrophages, which accelerates bacterium dissemination and expands tissue injury in host lungs. Mining drugs to counteract Mycobacterium tuberculosis-induced cell death would be beneficial to tuberculosis patients. METHODS: In this study, the protective drug was screened out from the FDA-approved drug library in Mycobacterium tuberculosis-infected macrophages with CCK-8 assay. The death mode regulated by the drug was identified using transcriptomic sequencing, cytomorphological observation, and in the experimental mouse Mycobacterium tuberculosis-infection model. The functional mechanism was explored using western blot, co-immunoprecipitation, and DARTS assay. The intracellular bacterial survival was detected using colony forming unit assays. RESULTS: Cisatracurium besylate was identified to be highly protective for the viability of macrophages during Mycobacterium tuberculosis infection via inhibiting necroptosis. Cisatracurium besylate prevented RIPK3 to be associated with the executive molecule MLKL for forming the necroptotic complex, resulting in the inhibition of MLKL phosphorylation and pore formation on cell membrane. However, Cisatracurium besylate did not interfere with the association between RIPK3 with its upstream kinase RIPK1 or ZBP1 but regulated RIPK3 autophosphorylation. Moreover, Cisatracurium besylate significantly inhibited the expansion of intracellular Mycobacterium tuberculosis both in vitro and in vivo, which also displayed a strong auxiliary bacteriostatic effect to support the therapeutic efficacy of isoniazid and rifampicin, the first-line anti-tubercular drugs. CONCLUSION: Cisatracurium besylate performs anti-Mycobacterium tuberculosis and anti-necroptotic roles, which potentiates its application to be an adjuvant drug for antituberculosis therapy to assist the battle against drug-resistant tuberculosis.
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Mycobacterium tuberculosis , Tuberculose , Camundongos , Animais , Apoptose , Mycobacterium tuberculosis/metabolismo , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Necroptose , Proteínas Quinases/metabolismo , Tuberculose/tratamento farmacológico , Tuberculose/metabolismo , Antibacterianos/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Macrófagos/metabolismoRESUMO
OBJECTIVE: Mycobacterium tuberculosis /human immunodeficiency virus (MTB/HIV) coinfection has become an urgent problem in the field of prevention and control of infectious diseases in recent years. Adoptive cellular immunotherapy using antigen-specific T-cell receptor (TCR) engineered T cells which recognize the specific antigen artificially may have tremendous potential in anti-MTB/HIV coinfection. We have previously successfully identified a MTB Ag85B 199-207 and HIV-1 Env 120-128 peptide-bispecific TCR screened out from peripheral blood mononuclear cells of a HLA-A∗0201 + healthy individual and have further studied that how residues on the predicted complementarity determining region (CDR) 3 of the ß chain contribute to the bispecific TCR contact with the peptide-MHC. However, it is not clear which amino acids in the predicted CDR3α of the bispecific TCR play a crucial role in ligand recognition. METHODS: The variants in the CDR3α of the bispecific TCR were generated using alanine substitution. We then evaluated the immune effects of the five variants on T-cell recognition upon encounter with the MTB or HIV-1 antigen. RESULTS: Mutation of two amino acids (E112A, Y115A) in CDR3α of the bispecific TCR caused a markedly diminished T-cell response to antigen, whereas mutation of the other three amino acids (S113A, P114A, S116A) resulted in completely eliminated response. CONCLUSION: This study demonstrates that Ser 113 , Pro 114 and Ser 116 in CDR3α of the bispecific TCR are especially important for antigen recognition. These results will pave the way for the future development of an improved high-affinity bispecific TCR for use in adoptive cellular immunotherapy for MTB/HIV coinfected patients.
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Infecções por HIV , HIV-1 , Mycobacterium tuberculosis , Humanos , Regiões Determinantes de Complementaridade/genética , Leucócitos Mononucleares , Infecções por HIV/terapia , Aminoácidos , Sítios de LigaçãoRESUMO
OBJECTIVES AND DESIGN: Dendritic cells (DCs) are one of the key immune cells in bridging innate and adaptive immune response against Mycobacterium tuberculosis (Mtb) infection. Interferons (IFNs) play important roles in regulating DC activation and function. Virus-inhibitory protein, endoplasmic reticulum-associated, interferon-inducible (Viperin) is one of the important IFN-stimulated genes (ISGs), and elicits host defense against infection. METHODS: We investigated the effects and mechanisms of Viperin on DC activation and function using Viperin deficient bone marrow-derived dendritic cells (BMDCs) during Mtb infection. RESULTS: Viperin deficiency enhanced phagocytic activity and increased clearance of Mtb in DCs, produced higher abundance of NO, cytokine including interleukin-12 (IL-12), Tumor necrosis factor-α (TNF-α), IL-1ß, IL-6 and chemokine including CXCL1, CXCL2 and CXCL10, elevated MHC I, MHC II and co-stimulatory molecules expression, and enhanced CD4+ and CD8+ T cell responses. Mechanistically, Viperin deficiency promoted DC activation and function through NF-κB p65 activation. NF-κB p65 inhibitor prevented cytokine and chemokine production, and co-stimulatory molecules expression promoted by Viperin deficiency. CONCLUSIONS: These results suggest that Mtb induced Viperin expression could impair the activation of host defense function of DCs and DC-T cell cross talk during Mtb infection. This research may provide a potential target for future HDT in TB therapy.
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Mycobacterium tuberculosis , Tuberculose , Proteína Viperina , Quimiocinas/metabolismo , Citocinas , Células Dendríticas , Mycobacterium tuberculosis/metabolismo , NF-kappa B/metabolismo , Proteína Viperina/metabolismo , AnimaisRESUMO
Mycobacterium tuberculosis (Mtb) infection is a long-standing public health threat, and the development of host-directed therapy for eradicating Mtb infection requires better insights into Mtb-host interactions. Viperin [virus-inhibitory protein, endoplasmic reticulum-associated, interferon (IFN) inducible] is an IFN-inducible protein with broad antiviral activities. Here, we demonstrated that Viperin was increased in abundance in patients with lymphatic and pulmonary tuberculosis (TB). Viperin-deficient mice had decreased Mtb bacterial loads and enhanced macrophage responses compared with their wild-type counterparts. Viperin suppressed the formation of a complex containing interleukin-1 receptor-associated kinase 1, TNF receptor-associated factor 6, and transforming growth factor ß-activated kinase 1 (TAK1) and inhibited the TAK1-dependent activation of IκB kinase α/ß, thereby impairing the production of nitric oxide and proinflammatory cytokines. These results suggest that Viperin promotes Mtb infection by inhibiting host innate immune responses in macrophages, suggesting that Viperin may be a candidate target for adjunct host-directed therapy in patients with TB.
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Quinases Associadas a Receptores de Interleucina-1 , Fator 6 Associado a Receptor de TNF , Animais , Antivirais/metabolismo , Citocinas/metabolismo , Quinase I-kappa B/metabolismo , Imunidade Inata , Interferons/metabolismo , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/metabolismo , MAP Quinase Quinase Quinases , Camundongos , Óxido Nítrico/metabolismo , Proteínas , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Crescimento Transformador beta/metabolismoRESUMO
BACKGROUND: As deubiquitinases (DUBs), ubiquitin C-terminal hydrolase (UCH)-L1 has been shown to play a crucial role in regulating diverse biological processes. However, its function in macrophage polarization remains unclear. METHODS: We performed in vivo and in vitro experiments to investigate the role of ubiquitin carboxyl-terminal hydrolase L1 (UCHL1), a kind of DUBs, in macrophage differentiation by using UCHL1-deficiency mice. RESULTS: We demonstrated that LPS stimulation induced UCHL1 expression in macrophages. The deficiency of UCHL1 expression decreased the expression of CD80 and CD86 but increased the expression of CD206. The expression of TNF-α, IL-6, iNOS, and IL-10 was downregulated, while that of Arg1, Ym1, and Fizz1 was upregulated in UCHL1 deficient macrophages. Moreover, we observed that UCHL1 promoted the degradation of p110α through autophagy, but paradoxically increased the activity of AKT, thereby promoting polarization of macrophages into pro-inflammatory states. CONCLUSION: In this study, we identified UCHL1 as a positive regulator of M1 macrophage polarization. Our findings may help in developing therapeutic interventions for the treatment of inflammatory diseases and pathogenic infections.
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Mycobacterium tuberculosis, the pathogen that causes tuberculosis, exhibits complex host-pathogen interactions. Pattern recognition receptors and their downstream signaling pathways play crucial roles in determining the outcome of infection. In particular, the scaffold protein ß-arrestin 2 mediates downstream signaling of G protein-coupled receptors. However, the role of ß-arrestin 2 in conferring immunity against M. tuberculosis has not yet been explored. We found that ß-arrestin 2 was upregulated in the lesioned regions of lung tissues in patients with tuberculosis. M. tuberculosis infection upregulated ß-arrestin 2 expression in human macrophages, and silencing of ß-arrestin 2 significantly enhanced bactericidal activity by enhancing the expression of proinflammatory cytokines such as TNF-α. ß-Arrestin 2 was shown to inhibit the activation of the TLR2/ERK1/2 pathway and its transcriptional regulation activity upon M. tuberculosis infection. Furthermore, ß-arrestin 2 transcriptionally regulates TNF-α by binding to CREB1. These observations revealed that the upregulation of ß-arrestin 2 is critical for M. tuberculosis to escape immune surveillance through an unknown mechanism. Our research offers a novel interference modality to enhance the immune response against tuberculosis by targeting ß-arrestin 2 to modulate the TLR2-ß-arrestin 2-ERK1/2-CREB1-TNF-α regulatory axis.
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Inflamação/imunologia , Tuberculose/imunologia , beta-Arrestina 2/imunologia , Adolescente , Células Cultivadas , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/imunologia , Masculino , Pessoa de Meia-IdadeRESUMO
Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) infection is the deadliest infectious disease and a global health problem. Macrophages (Mφs) and neutrophils that can phagocytose Mtb represent the first line of immune response to infection. Glycogen synthase kinase-3α/ß (GSK-3α/ß) represents a regulatory switch in host immune responses. However, the efficacy and molecular mechanisms of how GSK-3α/ß interacts with Mtb infection in Mφs remain undefined. Here, we demonstrated that Mtb infection downregulated GSK-3α/ß activity and promoted matrix metalloproteinase-1 (MMP-1) and MMP-9 expressions in Mφs derived from acute monocytic human leukemia THP-1 cells (THP-1-Mφs). We confirmed the upregulation of MMP-9 expression in tissues of TB patients compared with patients of chronic inflammation (CI). In THP-1-Mφs and C57BL/6 mice, GSK-3α/ß inhibitor SB216763 significantly increased MMP-1/9 production and facilitated Mtb load, while MMP inhibitors blocked MMP-1/9 expression and Mtb infection. Consistently, GSK-3α/ß silencing significantly increased MMP-1/9 expression and Mtb infection, while overexpression of GSK-3α/ß and constitutive activated GSK-3α/ß mutants significantly reduced MMP-1/9 expression and Mtb infection in THP-1-Mφs. MMP-1/9 silencing reduced Mtb infection, while overexpression of MMP-1/9 promoted Mtb infection in THP-1-Mφs. We further found that GSK-3α/ß inhibition increased Mtb infection and MMP-1/9 expression was blocked by ERK1/2 inhibitor. Additionally, we showed that protein kinase C-δ (PKC-δ) and mammalian target of rapamycin (mTOR) reduced GSK-3α/ß activity and promoted MMP-1/9 production in Mtb-infected THP-1-Mφs. In conclusion, this study suggests that PKC-δ-mTOR axis suppresses GSK-3α/ß activation with acceleration of MMP-1/9 expression through phospho-ERK1/2. These results reveal a novel immune escape mechanism of Mtb and a novel crosstalk between these critical signaling pathways in anti-TB immunity.
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Glicogênio Sintase Quinase 3 beta/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Tuberculose/metabolismo , Animais , Células Cultivadas , Feminino , Humanos , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/patogenicidade , Transdução de Sinais/fisiologia , Células THP-1/metabolismoRESUMO
Vitamin B6 is necessary to maintain normal metabolism and immune response, especially the anti-inflammatory immune response. However, the exact mechanism by which vitamin B6 plays the anti-inflammatory role is still unclear. Here, we report a novel mechanism of preventing excessive inflammation by vitamin B6 via reduction in the accumulation of sphingosine-1-phosphate (S1P) in a S1P lyase (SPL)-dependent manner in macrophages. Vitamin B6 supplementation decreased the expression of pro-inflammatory cytokines by suppressing nuclear factor-κB and mitogen-activated protein kinases signalling pathways. Furthermore, vitamin B6-reduced accumulation of S1P by promoting SPL activity. The anti-inflammatory effects of vitamin B6 were inhibited by S1P supplementation or SPL deficiency. Importantly, vitamin B6 supplementation protected mice from lethal endotoxic shock and attenuated experimental autoimmune encephalomyelitis progression. Collectively, these findings revealed a novel anti-inflammatory mechanism of vitamin B6 and provided guidance on its clinical use.
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Aldeído Liases/metabolismo , Inflamação/metabolismo , Lisofosfolipídeos/metabolismo , Macrófagos/metabolismo , Esfingosina/análogos & derivados , Vitamina B 6/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Progressão da Doença , Encefalomielite Autoimune Experimental/metabolismo , Lipopolissacarídeos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Choque/metabolismo , Transdução de Sinais , Esfingosina/metabolismoRESUMO
OBJECTIVES: Interferons (IFNs) play multifunctional roles in host defense against infectious diseases by inducing IFN-stimulated genes (ISGs). However, little is known about how ISGs regulate host immune response to Mycobacterium tuberculosis (Mtb) infection, the major cause of tuberculosis (TB). METHODS: We thus profiled the potential effects and mechanisms of eight Mtb-induced ISGs on Mtb infection by RNA interference in human macrophages (Mφs) derived from peripheral blood monocytes (hMDMs) and THP-1 cell line derived Mφs (THP-1-Mφs). RESULTS: MxA silencing significantly decreased intracellular Mtb infection in Mφs. Mechanistically, MxA silencing promoted inflammatory cytokines IL-1ß, IL-6 and TNF-α production, and induced NF-κB p65 activation. Pharmacological inhibition of NF-κB p65 activation or gene silencing of NF-κB p65 blocked the increased production of IL-1ß, IL-6 and TNF-α and restored Mtb infection by MxA silencing. Furthermore, pharmacological inhibition of TAK1 and IKKα/ß blocked NF-κB p65 activation and subsequent production of pro-inflammatory cytokines by MxA silencing. Isoniazid (INH) treatment and MxA silencing could promote TAK1-IKKα/ß-NF-κB signaling pathway activation and combat Mtb infection independently. CONCLUSIONS: Our results reveal a novel role of MxA in regulating TAK1-IKKα/ß-NF-κB signaling activation and production of antimicrobial inflammatory cytokines upon Mtb infection, providing a potential target for clinical treatment of TB.
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Mycobacterium tuberculosis , Tuberculose , Citocinas , Humanos , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Transdução de SinaisRESUMO
OBJECTIVES: Although it has been reported that Interferon regulatory factor 1 (IRF1) inhibits Mycobacterium tuberculosis (Mtb) infection via inducible nitric oxide synthase (iNOS) in mice, how it counteracts with mycobacterial infection in human remains largely obscure. This study was conducted to investigated the effect of IRF1 on Mtb infection in human macrophages (MÏs). METHODS: We thus investigated the IRF1 expression by using PBMC and monocytes of pulmonary tuberculosis (TB) patients and human monocyte-derived macrophages (hMDMs) and THP-1-derived macrophages (THP-1-MÏ). We used gain-of-function and loss-of-function approaches to explore the role of IRF1 on Mtb infection. RESULTS: IRF1 was significantly induced in PBMC and monocytes of pulmonary TB patients in vivo and in human MÏs in vitro. We demonstrated that IRF1 protects MÏs from Mtb infection. Concurrently, IRF1 promotes the expression of several pro-inflammatory cytokines including IL-6, TNF-α and IL-8, indicating IRF1-mediated activation of innate immunity upon Mtb infection. Gain-of-function and loss-of-function approaches have demonstrated that IRF1 suppresses the mechanistic target of rapamycin (mTOR)/p70 S6 kinase (p70 S6K) cascade to exert its anti-Mtb effect. CONCLUSIONS: The discovery of a novel function of IRF1 in facilitating anti-mycobacterial effect through suppressing mTOR/p70 S6K signaling in MÏs may provide a promoting therapeutic target for tuberculosis.
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Fator Regulador 1 de Interferon/metabolismo , Mycobacterium tuberculosis/fisiologia , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Tuberculose/metabolismo , Tuberculose/microbiologia , Autofagia , Interações Hospedeiro-Patógeno , Humanos , Macrófagos/metabolismo , Macrófagos/microbiologia , Monócitos/metabolismo , Monócitos/microbiologia , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tuberculose/genéticaRESUMO
Mycobacterium tuberculosis, which primarily infects mononuclear phagocytes, remains the leading bacterial cause of enormous morbidity and mortality because of bacterial infections in humans throughout the world. The IL-1 family of cytokines is critical for host resistance to M. tuberculosis As a newly discovered subgroup of the IL-1 family, although IL-36 cytokines have been proven to play roles in protection against M. tuberculosis infection, the antibacterial mechanisms are poorly understood. In this study, we demonstrated that IL-36γ conferred to human monocyte-derived macrophages bacterial resistance through activation of autophagy as well as induction of WNT5A, a reported downstream effector of IL-1 involved in several inflammatory diseases. Further studies showed that WNT5A could enhance autophagy of monocyte-derived macrophages by inducing cyclooxygenase-2 (COX-2) expression and in turn decrease phosphorylation of AKT/mTOR via noncanonical WNT signaling. Consistently, the underlying molecular mechanisms of IL-36γ function are also mediated by the COX-2/AKT/mTOR signaling axis. Altogether, our findings reveal a novel activity for IL-36γ as an inducer of autophagy, which represents a critical inflammatory cytokine that control the outcome of M. tuberculosis infection in human macrophages.
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Interleucina-1/imunologia , Macrófagos/imunologia , Tuberculose Pulmonar/imunologia , Proteína Wnt-5a/imunologia , Autofagia/imunologia , Humanos , Interleucina-1/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Mycobacterium tuberculosis/imunologia , Transdução de Sinais/imunologia , Tuberculose Pulmonar/metabolismo , Proteína Wnt-5a/metabolismoRESUMO
Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) represents one of the greatest threats to human health., Interferons (IFNs) in combination with the first-line of anti-TB drugs have been used for treating TB for decades in the clinic, but how Mtb infection regulates interferon-stimulated genes (ISGs) in human macrophages (MÏs) remains unknown. In this study, we investigated the expression-signature and associated innate signaling mechanisms of ISGs in Mtb-infected human monocyte-derived MÏs (hMDMs) and THP-1-derived MÏs (THP-1-MÏs). Among 28 of the detected ISGs, 90% of them exerted a significant increase in Mtb-infected MÏs. Additionally, we found that cytosolic cyclic (GMP-AMP) synthase (cGAS), toll-like receptor-2 (TLR-2) and TLR-4 signaling pathways participated in ISG induction. Their downstream elements of TANK-binding kinase 1 (TBK1), nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and Janus kinase-signal transducer and activator of transcription (JAK-STAT) were selectively involved in Mtb-mediated ISG production. Finally, the numerous types of ISG expression in hMDMs of TB patients were more susceptible to restimulation of Mtb infection or/and IFN treatment than that of healthy people. Hence, different signaling pathways define different ISG expression during Mtb infection and this helps to illustrate how ISGs are elucidated and to better understand the host immune responses to Mtb infection in MÏs.
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Interferon gama/farmacologia , Macrófagos/metabolismo , Transdução de Sinais , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Tuberculose Pulmonar/tratamento farmacológico , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Interferon gama/metabolismo , Interferon gama/uso terapêutico , Janus Quinase 1/metabolismo , Sistema de Sinalização das MAP Quinases , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Mycobacterium tuberculosis , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Transcrição STAT1/metabolismo , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/metabolismoRESUMO
γδ T cells are a subset of unconventional T cells that serve a critical role in infectious diseases and various types of cancer. Cell therapy with geneticallymodified γδ T cells is regarded as a promising tool for tumor treatment. However, since γδ T cells constitute a minority of T cells, their largescale expansion is difficult to realize in an efficient and costeffective manner. In the present study, based on previous studies, culture protocols for γδ T cells were tested using different combinations of isopentenyl pyrophosphate and interleukin 2 in order to satisfy different experimental purposes. One protocol was demonstrated to be the most suitable for lentiviral transduction. These results greatly reinforce the promising prospects of using γδ T cells in basic research and for clinical applications.