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1.
JCI Insight ; 9(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38016036

RESUMO

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.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/genética , Macrófagos/metabolismo
2.
Neurosci Bull ; 40(1): 17-34, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37498431

RESUMO

Multiple sclerosis (MS) is a neuroinflammatory demyelinating disease, mediated by pathogenic T helper 17 (Th17) cells. However, the therapeutic effect is accompanied by the fluctuation of the proportion and function of Th17 cells, which prompted us to find the key regulator of Th17 differentiation in MS. Here, we demonstrated that the triggering receptor expressed on myeloid cells 2 (TREM-2), a modulator of pattern recognition receptors on innate immune cells, was highly expressed on pathogenic CD4-positive T lymphocyte (CD4+ T) cells in both patients with MS and experimental autoimmune encephalomyelitis (EAE) mouse models. Conditional knockout of Trem-2 in CD4+ T cells significantly alleviated the disease activity and reduced Th17 cell infiltration, activation, differentiation, and inflammatory cytokine production and secretion in EAE mice. Furthermore, with Trem-2 knockout in vivo experiments and in vitro inhibitor assays, the TREM-2/zeta-chain associated protein kinase 70 (ZAP70)/signal transducer and activator of transcription 3 (STAT3) signal axis was essential for Th17 activation and differentiation in EAE progression. In conclusion, TREM-2 is a key regulator of pathogenic Th17 in EAE mice, and this sheds new light on the potential of this therapeutic target for MS.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Animais , Humanos , Camundongos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Diferenciação Celular , Encefalomielite Autoimune Experimental/metabolismo , Camundongos Endogâmicos C57BL , Células Th1/metabolismo , Células Th1/patologia
3.
PLoS Pathog ; 19(12): e1011827, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38039266

RESUMO

[This corrects the article DOI: 10.1371/journal.ppat.1011480.].

4.
Cell Rep ; 42(10): 113231, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37804507

RESUMO

Ubiquitination is an important protein modification that regulates diverse biological processes, including CD4+ T cell differentiation and functions. However, the function of most E3 ubiquitin ligases in CD4+ T cell differentiation and CD4+ T cell-mediated pathological diseases remains unclear. In this study, we find that tripartite motif-containing motif 11 (TRIM11) specifically negatively regulates regulatory T (Treg) cell differentiation in CD4+ T cells and promotes autoimmune disease development in an AIM2-dependent manner. Mechanistically, TRIM11 interacts with absent in melanoma 2 (AIM2) and promotes the selective autophagic degradation of AIM2 by inducing AIM2 ubiquitination and binding to p62 in CD4+ T cells. AIM2 attenuates AKT and FOXO1 phosphorylation, MYC signaling, and glycolysis, thereby promoting the stability of Treg cells during experimental autoimmune encephalomyelitis (EAE). Our findings suggest that TRIM11 serves as a potential target for immunotherapeutic intervention for dysregulated immune responses that lead to autoimmunity and cancers.


Assuntos
Encefalomielite Autoimune Experimental , Melanoma , Linfócitos T Reguladores , Animais , Diferenciação Celular , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais/fisiologia , Linfócitos T Reguladores/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteína Sequestossoma-1/metabolismo , Autofagia/genética , Autofagia/fisiologia
5.
Theranostics ; 13(11): 3509-3523, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37441600

RESUMO

Background: CD4+ T cells play an important role in body development and homeostasis. Quantitative and functional changes in CD4+ T cells result in abnormal immune responses, which lead to inflammation, cancer, or autoimmune diseases, such as multiple sclerosis (MS). Ubiquitination plays an essential role in the differentiation and functioning of CD4+ T cells. However, the function of several E3 ubiquitin ligases in CD4+ T cell differentiation and T cell-mediated pathological diseases remains unclear. Methods: RNA sequencing data were analyzed to identify the E3 ubiquitin ligases that participate in the pathogenesis of MS. Furthermore, conditional knockout mice were generated. Specifically, flow cytometry, qPCR, western blot, CO-IP and cell transfer adoptive experiments were performed. Results: In this study, we identified The RING finger 157 (RNF157) as a vital regulator of CD4+ T cell differentiation; it promoted Th1 differentiation but attenuated Th17 differentiation and CCR4 and CXCR3 expressions in CD4+ T cells, thereby limiting experimental autoimmune encephalomyelitis development. Mechanistically, RNF157 in CD4+ T cells targeted HDAC1 for K48-linked ubiquitination and degradation. Notably, RNF157 expression was significantly decreased and showed a significant negative correlation with RORγt expression in patients with MS. Conclusions: Our study highlights the critical role of RNF157 in regulating CD4+ T cell functions in autoimmune diseases and suggests RNF157 as a potential target in adaptive immune responses against MS and other autoimmune disorders.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Camundongos , Animais , Autoimunidade , Ubiquitinação , Encefalomielite Autoimune Experimental/metabolismo , Esclerose Múltipla/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Diferenciação Celular , Camundongos Knockout , Linfócitos T CD4-Positivos , Ubiquitinas/metabolismo , Camundongos Endogâmicos C57BL
6.
PLoS Pathog ; 19(7): e1011480, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37410794

RESUMO

Deubiquitinating enzymes (DUBs) regulate antiviral immune response through targeting DNA sensor signaling pathway members. As one of the DNA sensors, interferon (IFN)-γ inducible protein 16 (IFI16) play a major role in response to virus infections through activating the canonical STING/TBK-1/IRF3 signaling pathway. Only a few studies discuss the function of DUBs in IFI16-mediated antiviral response. Ubiquitin-specific protease 12 (USP12), which is one of the major members of the USP family, participates in various biological functions. However, whether USP12 regulates the nucleic acid sensor to modulate antiviral immune responses has not yet been elucidated. In this study, we found that knockout or knockdown of USP12 impaired the HSV-1-induced expressions of IFN-ß, CCL-5, IL-6, and downstream interferon-stimulated genes (ISGs). Moreover, USP12 deficiency increased HSV-1 replication and host susceptibility to HSV-1 infection. Mechanistically, USP12 inhibited the proteasome-dependent degradation of IFI16 through its deubiquitinase activity, thereby maintaining IFI16 stability and promoting IFI16-STING-IRF3- and p65-mediated antiviral signaling. Overall, our findings demonstrate an essential role of USP12 in DNA-sensing signaling and contribute to the understanding of deubiquitination-mediated regulation of innate antiviral responses.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Humanos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Herpesvirus Humano 1/fisiologia , Interferons/metabolismo , Antivirais/metabolismo , Imunidade Inata , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo
7.
Sci Signal ; 16(788): eabm1756, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37279284

RESUMO

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.


Assuntos
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/metabolismo
8.
Int Immunopharmacol ; 120: 110291, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37182451

RESUMO

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.


Assuntos
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/metabolismo
9.
Cell Mol Immunol ; 20(3): 252-263, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36600049

RESUMO

The balance between inflammatory T helper type 17 (Th17) and immunosuppressive regulatory T (Treg) cells is critical for maintaining immune homeostasis in the human body and is tightly regulated under healthy conditions. An increasing number of studies have reported that deubiquitinases (DUBs) play a vital role in regulating Th17- and Treg-cell differentiation. However, the biological functions of only a small fraction of DUBs in Th17- and Treg-cell differentiation are well defined. In this study, we identified ubiquitin-specific peptidase 1 (USP1) as a vital regulator of CD4+ T-cell differentiation. USP1 promoted Th17-cell differentiation but attenuated Treg-cell differentiation, thereby promoting the development of inflammatory diseases. Mechanistically, USP1 in CD4+ T cells enhanced the activity of RORγt but promoted the proteasomal degradation of Foxp3 through deubiquitination and stabilization of TAZ in vitro and in vivo. Notably, ML323, a specific inhibitor of the USP1/UAF1 deubiquitinase complex, inhibited Th17-cell differentiation and promoted Treg-cell differentiation in vitro and in vivo, indicating that ML323 might be a promising candidate for the treatment of diseases associated with an imbalance between Th17 and Treg cells. Our study highlights the critical role of USP1 in regulating adaptive immune responses and suggests that USP1 might be a drug target for the treatment of diseases associated with an imbalance between Th17 and Treg cells.


Assuntos
Linfócitos T Reguladores , Células Th17 , Humanos , Diferenciação Celular , Fatores de Transcrição , Proteases Específicas de Ubiquitina
10.
AIDS ; 37(1): 33-42, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36281689

RESUMO

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.


Assuntos
Infecções por HIV , HIV-1 , Mycobacterium tuberculosis , Humanos , Regiões Determinantes de Complementaridade/genética , Leucócitos Mononucleares , Infecções por HIV/terapia , Aminoácidos , Sítios de Ligação
11.
Inflamm Res ; 72(1): 27-41, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36315280

RESUMO

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.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Proteína Viperina , Quimiocinas/metabolismo , Citocinas , Células Dendríticas , Mycobacterium tuberculosis/metabolismo , NF-kappa B/metabolismo , Proteína Viperina/metabolismo , Animais
12.
Sci Signal ; 15(754): eabe1621, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36194648

RESUMO

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.


Assuntos
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/metabolismo
13.
Immunology ; 167(4): 544-557, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35898171

RESUMO

The relative abundance of myeloid-derived suppressor cells (MDSCs) compared to cytotoxic T cells determines the outcomes of diseases and the efficacy of immunotherapy. Ubiquitin-specific peptidase 12 (USP12), a member of the USP family of deubiquitinases, targets multiple signalling pathways and regulates diverse biological processes, including cell proliferation and survival. It is well known that ubiquitylation is an important mechanism for regulating the immune response. However, it is unclear whether USP12 regulates tumour growth by influencing MDSCs. In the present study, we reported that USP12 deficiency decreased infiltration and impaired the suppressor function of monocytic (M)-MDSCs, resulting in increased CD8+ T-cell response and decelerated tumour growth. USP12-knockout M-MDSCs were less potent in inhibiting the proliferation of CD8+ T cells and their ability to secrete IFN-γ. Furthermore, USP12 deficiency inhibited the suppressor function of M-MDSCs by downregulating the negative regulatory molecules inducible nitric oxide synthase and PD-L1, through deubiquitinating and stabilizing p65. Our results suggest that USP12 is a positive regulator of M-MDSCs and may serve as a potential target for antitumor therapy.


Assuntos
Células Supressoras Mieloides , Neoplasias , Humanos , Linfócitos T CD8-Positivos , Transdução de Sinais , Proliferação de Células , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
14.
Cent Eur J Immunol ; 47(1): 30-40, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600157

RESUMO

Chronic inflammation develops when the immune system is unable to clear a persistent insult. Unresolved chronic inflammation leads to immunosuppression to maintain the internal homeostatic conditions, which is mediated primarily by myeloid-derived suppressor cells (MDSCs). Toll-like receptors 2 (TLR2) has an important role in chronic inflammation and can be activated by a vast number and diversity of TLR2 ligands, for example Pam2CSK4. However, the regulatory effect of TLR2 signaling on MDSCs in chronic inflammation remains controversial. This study demonstrated that heat-killed Mycobacterium bovis BCG-induced pathology-free chronic inflammation triggered suppressive monocytic MDSCs (M-MDSCs) that expressed TLR2. Activation of TLR2 signaling by Pam2CSK4 treatment enhanced immunosuppression of M-MDSCs by upregulating inducible nitric oxide synthase (iNOS) activity and nitric oxide (NO) production partly through signal transducer and activator of transcription 3 (STAT3) activation. Thus, TLR2 has a fundamental role in promoting the MDSC-mediated immunosuppressive environment during chronic inflammation and might represent a potentially therapeutic target in chronic inflammation disease.

15.
J Inflamm Res ; 15: 735-746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35153498

RESUMO

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.

16.
Inflammation ; 45(4): 1484-1495, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35083625

RESUMO

MicroRNAs are small non-coding RNA regulatory molecules that play an important role in the development and function of immune cells. MicroRNA-26a (miR-26a) exhibits anti-inflammatory immune effects on immune cells. However, the exact mechanism by which miR-26a plays an anti-inflammatory role remains unclear. Here, we report that miR-26a reduces inflammatory response via inhibition of prostaglandin E2 (PGE2) production by targeting cyclooxygenase-2 (COX-2). We found that miR-26a was downregulated in vitro and in vivo. The miR-26a mimic significantly decreased COX-2 protein levels, further inhibiting pro-inflammatory cytokine production in LPS-stimulated macrophages. We predicted that miR-26a could potentially target COX-2 in LPS-stimulated macrophages. Computational algorithms showed that the 3'-UTR of COX-2 mRNA contains a binding site for miR-26a. This putative targeting relationship between miR-26a and COX-2 was further confirmed by a dual-reporter gene assay. The anti-inflammatory effects of the miR-26a mimic were diminished by PGE2 supplementation. Importantly, miR-26a mimics protected mice from lethal endotoxic shock and attenuated pro-inflammatory cytokine production. Collectively, these results suggest that miR-26a may function as a novel feedback negative regulator of the hyperinflammatory response and as a drug target for the progression of inflammation.


Assuntos
Ciclo-Oxigenase 2 , Dinoprostona , MicroRNAs , Regiões 3' não Traduzidas , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Dinoprostona/biossíntese , Inflamação , Lipopolissacarídeos , Camundongos , MicroRNAs/genética
17.
J Clin Invest ; 131(17)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34623322

RESUMO

Triggering receptor expressed on myeloid cells 2 (TREM-2) is a modulator of pattern recognition receptors on innate immune cells that regulates the inflammatory response. However, the role of TREM-2 in in vivo models of infection and inflammation remains controversial. Here, we demonstrated that TREM-2 expression on CD4+ T cells was induced by Mycobacterium tuberculosis infection in both humans and mice and positively associated with T cell activation and an effector memory phenotype. Activation of TREM-2 in CD4+ T cells was dependent on interaction with the putative TREM-2 ligand expressed on DCs. Unlike the observation in myeloid cells that TREM-2 signals through DAP12, in CD4+ T cells, TREM-2 interacted with the CD3ζ-ZAP70 complex as well as with the IFN-γ receptor, leading to STAT1/-4 activation and T-bet transcription. In addition, an infection model using reconstituted Rag2-/- mice (with TREM-2-KO vs. WT cells or TREM-2+ vs. TREM-2-CD4+ T cells) or CD4+ T cell-specific TREM-2 conditional KO mice demonstrated that TREM-2 promoted a Th1-mediated host defense against M. tuberculosis infection. Taken together, these findings reveal a critical role of TREM-2 in evoking proinflammatory Th1 responses that may provide potential therapeutic targets for infectious and inflammatory diseases.


Assuntos
Complexo CD3/imunologia , Glicoproteínas de Membrana/imunologia , Receptores Imunológicos/imunologia , Células Th1/imunologia , Tuberculose/imunologia , Proteína-Tirosina Quinase ZAP-70/imunologia , Adulto , Animais , Modelos Animais de Doenças , Feminino , Humanos , Imunidade Inata , Ativação Linfocitária , Masculino , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Modelos Imunológicos , Mycobacterium tuberculosis/imunologia , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Receptores de Reconhecimento de Padrão/imunologia , Fatores de Transcrição STAT/imunologia
18.
Cell Death Differ ; 28(10): 2857-2870, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33941870

RESUMO

Deubiquitinases (DUBs) regulate diverse biological processes and represent a novel class of drug targets. However, the biological function of only a small fraction of DUBs, especially in adaptive immune response regulation, is well-defined. In this study, we identified DUB ubiquitin-specific peptidase 12 (USP12) as a critical regulator of CD4+ T cell activation. USP12 plays an intrinsic role in promoting the CD4+ T cell phenotype, including differentiation, activation, and proliferation. Although USP12-deficient CD4+ T cells protected mice from autoimmune diseases, the immune response against bacterial infection was subdued. USP12 stabilized B cell lymphoma/leukemia 10 (BCL10) by deubiquitinating, and thereby activated the NF-κB signaling pathway. Interestingly, this USP12 regulatory mechanism was identified in CD4+ T cells, but not in CD8+ T cells. Our study results showed that USP12 activated CD4+ T cell signaling, and targeting USP12 might help develop therapeutic interventions for treating inflammatory diseases or pathogen infections.


Assuntos
Proteína 10 de Linfoma CCL de Células B/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Enzimas Desubiquitinantes/metabolismo , Linfócitos T/metabolismo , Ubiquitina Tiolesterase/metabolismo , Animais , Proliferação de Células , Camundongos
19.
J Immunol ; 206(11): 2623-2637, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34001657

RESUMO

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.


Assuntos
Inflamação/imunologia , Tuberculose/imunologia , beta-Arrestina 2/imunologia , Adolescente , Células Cultivadas , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/imunologia , Masculino , Pessoa de Meia-Idade
20.
Front Immunol ; 12: 752466, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095838

RESUMO

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.


Assuntos
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/metabolismo
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