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1.
Nat Commun ; 10(1): 4766, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628327

RESUMO

Trisomy 21 (T21) causes Down syndrome (DS), affecting immune and neurological function by ill-defined mechanisms. Here we report a large metabolomics study of plasma and cerebrospinal fluid, showing in independent cohorts that people with DS produce elevated levels of kynurenine and quinolinic acid, two tryptophan catabolites with potent immunosuppressive and neurotoxic properties, respectively. Immune cells of people with DS overexpress IDO1, the rate-limiting enzyme in the kynurenine pathway (KP) and a known interferon (IFN)-stimulated gene. Furthermore, the levels of IFN-inducible cytokines positively correlate with KP dysregulation. Using metabolic tracing assays, we show that overexpression of IFN receptors encoded on chromosome 21 contribute to enhanced IFN stimulation, thereby causing IDO1 overexpression and kynurenine overproduction in cells with T21. Finally, a mouse model of DS carrying triplication of IFN receptors exhibits KP dysregulation. Together, our results reveal a mechanism by which T21 could drive immunosuppression and neurotoxicity in DS.


Assuntos
Cromossomos Humanos Par 21/genética , Síndrome de Down/genética , Cinurenina/metabolismo , Receptores de Interferon/genética , Trissomia , Animais , Vias Biossintéticas/genética , Linhagem Celular , Citocinas/metabolismo , Síndrome de Down/metabolismo , Expressão Gênica , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Metabolômica/métodos , Camundongos Endogâmicos C57BL , Ácido Quinolínico/metabolismo , Receptores de Interferon/metabolismo
2.
Nat Neurosci ; 22(8): 1276-1288, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31235930

RESUMO

T cells clear virus from the CNS and dynamically regulate brain functions, including spatial learning, through cytokine signaling. Here we determined whether hippocampal T cells that persist after recovery from infection with West Nile virus (WNV) or Zika virus (ZIKV) impact hippocampal-dependent learning and memory. Using newly established models of viral encephalitis recovery in adult animals, we show that in mice that have recovered from WNV or ZIKV infection, T cell-derived interferon-γ (IFN-γ) signaling in microglia underlies spatial-learning defects via virus-target-specific mechanisms. Following recovery from WNV infection, mice showed presynaptic termini elimination with lack of repair, while for ZIKV, mice showed extensive neuronal apoptosis with loss of postsynaptic termini. Accordingly, animals deficient in CD8+ T cells or IFN-γ signaling in microglia demonstrated protection against synapse elimination following WNV infection and decreased neuronal apoptosis with synapse recovery following ZIKV infection. Thus, T cell signaling to microglia drives post-infectious cognitive sequelae that are associated with emerging neurotropic flaviviruses.


Assuntos
Transtornos Cognitivos/psicologia , Infecções por Flavivirus/imunologia , Infecções por Flavivirus/psicologia , Microglia/imunologia , Sinapses/imunologia , Sinapses/patologia , Linfócitos T/imunologia , Animais , Apoptose , Linfócitos T CD8-Positivos/imunologia , Transtornos Cognitivos/etiologia , Feminino , Infecções por Flavivirus/patologia , Interferon gama , /psicologia , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interferon/genética , Febre do Nilo Ocidental/imunologia , Febre do Nilo Ocidental/psicologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/psicologia
3.
Nat Immunol ; 20(8): 1035-1045, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31235953

RESUMO

Type III interferon (IFN-λ) is important for innate immune protection at mucosal surfaces and has therapeutic benefit against influenza A virus (IAV) infection. However, the mechanisms by which IFN-λ programs adaptive immune protection against IAV are undefined. Here we found that IFN-λ signaling in dendritic cell (DC) populations was critical for the development of protective IAV-specific CD8+ T cell responses. Mice lacking the IFN-λ receptor (Ifnlr1-/-) had blunted CD8+ T cell responses relative to wild type and exhibited reduced survival after heterosubtypic IAV re-challenge. Analysis of DCs revealed IFN-λ signaling directed the migration and function of CD103+ DCs for development of optimal antiviral CD8+ T cell responses, and bioinformatic analyses identified IFN-λ regulation of a DC IL-10 immunoregulatory network. Thus, IFN-λ serves a critical role in bridging innate and adaptive immunity from lung mucosa to lymph nodes to program DCs to direct effective T cell immunity against IAV.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Vírus da Influenza A/imunologia , Interferon gama/imunologia , Infecções por Orthomyxoviridae/imunologia , Receptores de Interferon/imunologia , Animais , Linhagem Celular , Cães , Feminino , Imunidade Inata/imunologia , Interleucina-10/imunologia , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interferon/genética
4.
Nature ; 567(7746): 56-60, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30814731

RESUMO

The cytokine interferon-γ (IFNγ) is a central coordinator of innate and adaptive immunity, but its highly pleiotropic actions have diminished its prospects for use as an immunotherapeutic agent. Here, we took a structure-based approach to decoupling IFNγ pleiotropy. We engineered an affinity-enhanced variant of the ligand-binding chain of the IFNγ receptor IFNγR1, which enabled us to determine the crystal structure of the complete hexameric (2:2:2) IFNγ-IFNγR1-IFNγR2 signalling complex at 3.25 Å resolution. The structure reveals the mechanism underlying deficits in IFNγ responsiveness in mycobacterial disease syndrome resulting from a T168N mutation in IFNγR2, which impairs assembly of the full signalling complex. The topology of the hexameric complex offers a blueprint for engineering IFNγ variants to tune IFNγ receptor signalling output. Unexpectedly, we found that several partial IFNγ agonists exhibited biased gene-expression profiles. These biased agonists retained the ability to induce upregulation of major histocompatibility complex class I antigen expression, but exhibited impaired induction of programmed death-ligand 1 expression in a wide range of human cancer cell lines, offering a route to decoupling immunostimulatory and immunosuppressive functions of IFNγ for therapeutic applications.


Assuntos
Desenho de Drogas , Interferon gama/agonistas , Interferon gama/imunologia , Receptores de Interferon/química , Receptores de Interferon/metabolismo , Antígeno B7-H1/biossíntese , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Agonismo Parcial de Drogas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/biossíntese , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Interferon gama/química , Interferon gama/genética , Ligantes , Modelos Moleculares , Mutação , Infecções por Mycobacterium/genética , Infecções por Mycobacterium/imunologia , Estabilidade Proteica , Receptores de Interferon/genética , Transdução de Sinais , Relação Estrutura-Atividade
5.
Nat Immunol ; 20(5): 593-601, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30886417

RESUMO

Interferon-λ (IFN-λ) acts on mucosal epithelial cells and thereby confers direct antiviral protection. In contrast, the role of IFN-λ in adaptive immunity is far less clear. Here, we report that mice deficient in IFN-λ signaling exhibited impaired CD8+ T cell and antibody responses after infection with a live-attenuated influenza virus. Virus-induced release of IFN-λ triggered the synthesis of thymic stromal lymphopoietin (TSLP) by M cells in the upper airways that, in turn, stimulated migratory dendritic cells and boosted antigen-dependent germinal center reactions in draining lymph nodes. The IFN-λ-TSLP axis also boosted production of the immunoglobulins IgG1 and IgA after intranasal immunization with influenza virus subunit vaccines and improved survival of mice after challenge with virulent influenza viruses. IFN-λ did not influence the efficacy of vaccines applied by subcutaneous or intraperitoneal routes, indicating that IFN-λ plays a vital role in potentiating adaptive immune responses that initiate at mucosal surfaces.


Assuntos
Imunidade Adaptativa/imunologia , Citocinas/imunologia , Imunidade nas Mucosas/imunologia , Interleucinas/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Imunidade Adaptativa/genética , Animais , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/virologia , Imunidade nas Mucosas/efeitos dos fármacos , Imunidade nas Mucosas/genética , Imunização/métodos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/imunologia , Vírus da Influenza A/fisiologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Interleucinas/administração & dosagem , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Receptores de Interferon/metabolismo
6.
Viruses ; 11(3)2019 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-30857305

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is the causative agent of a tick-borne infection with a significant mortality rate of up to 40% in endemic areas, with evidence of geographical expansion. Due to a lack of effective therapeutics and control measures, the development of a protective CCHFV vaccine remains a crucial public health task. This paper describes, for the first time, a Bovine herpesvirus type 4 (BoHV-4)-based viral vector (BoHV4-∆TK-CCHFV-N) and its immunogenicity in BALB/c and protection potential in IFNα/ß/γR-/- mice models in comparison with two routinely used vaccine platforms, namely, Adenovirus type 5 and a DNA vector (pCDNA3.1 myc/His A), expressing the same antigen. All vaccine constructs successfully elicited significantly elevated cytokine levels and specific antibody responses in immunized BALB/c and IFNα/ß/γR-/- mice. However, despite highly specific antibody responses in both animal models, the antibodies produced were unable to neutralize the virus in vitro. In the challenge experiment, only the BoHV4-∆TK-CCHFV-N and Ad5-N constructs produced 100% protection against lethal doses of the CCHFV Ank-2 strain in IFNα/ß/γR-/- mice. The delivery platforms could not be compared due to similar protection rates in IFNα/ß/γR-/- mice. However, during the challenge experiment in the T cell and passive antibody transfer assay, BoHV4-∆TK-CCHFV-N was dominant, with a protection rate of 75% compared to others. In conclusion, vector-based CCHFV N protein expression constitutes an effective approach for vaccine development and BoHV-4 emerged as a strong alternative to previously used viral vectors.


Assuntos
Vetores Genéticos , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Febre Hemorrágica da Crimeia/prevenção & controle , Imunização Passiva , Proteínas do Nucleocapsídeo/imunologia , Receptores de Interferon/genética , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Bovinos , Modelos Animais de Doenças , Feminino , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Febre Hemorrágica da Crimeia/imunologia , Herpesvirus Bovino 4/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Proteínas do Nucleocapsídeo/genética , Vacinação , Vacinas Virais/genética
7.
Front Immunol ; 10: 140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30792713

RESUMO

In lymphopenic mice, T cells become activated and undergo lymphopenia-induced proliferation (LIP). However, not all T cells are equally sensitive to lymphopenia. Several lymphopenia-insensitive T cell clones were described and their non-responsiveness was mainly attributed to clone-specific properties. Here, we provide evidence for an additional, host-dependent mechanism restraining LIP of lymphopenia-insensitive CD4+ T cells. We show that such cells undergo LIP in lymphopenic mice lacking IFN-γ receptor (IFN-γR) expression, a process, which is promoted by the autocrine action of T cell-derived IFN-γ. Additionally, LIP of lymphopenia-insensitive CD4+ T cells requires an intact microflora and is accompanied by the massive accumulation of IL-6 and dendritic cells (DCs). Consistent with these results, IL-6 neutralization and the DC-specific restoration of IFN-γR expression are both sufficient to restrict LIP. Hence, the insensitivity of CD4+ T cells to lymphopenia relies on cell-intrinsic properties and a complex interplay between the commensal microflora, IL-6, IFN-γR+ DCs, and T cell-derived IFN-γ.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Linfopenia/imunologia , Receptores de Interferon/imunologia , Animais , Proliferação de Células , Doença Crônica , Interleucina-6/imunologia , Camundongos Transgênicos , Receptores de Interferon/genética , Transdução de Sinais
8.
Viruses ; 11(2)2019 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-30717492

RESUMO

The 2014 Ebolavirus outbreak in West Africa highlighted the need for vaccines and therapeutics to prevent and treat filovirus infections. A well-characterized small animal model that is susceptible to wild-type filoviruses would facilitate the screening of anti-filovirus agents. To that end, we characterized knockout mice lacking α/ß and γ interferon receptors (IFNAGR KO) as a model for wild-type filovirus infection. Intraperitoneal challenge of IFNAGR KO mice with several known human pathogenic species from the genus Ebolavirus and Marburgvirus, except Bundibugyo ebolavirus and Taï Forest ebolavirus, caused variable mortality rate. Further characterization of the prototype Ebola virus Kikwit isolate infection in this KO mouse model showed 100% lethality down to a dilution equivalent to 1.0 × 10-1 pfu with all deaths occurring between 7 and 9 days post-challenge. Viral RNA was detectable in serum after challenge with 1.0 × 10² pfu as early as one day after infection. Changes in hematology and serum chemistry became pronounced as the disease progressed and mirrored the histological changes in the spleen and liver that were also consistent with those described for patients with Ebola virus disease. In a proof-of-principle study, treatment of Ebola virus infected IFNAGR KO mice with favipiravir resulted in 83% protection. Taken together, the data suggest that IFNAGR KO mice may be a useful model for early screening of anti-filovirus medical countermeasures.


Assuntos
Amidas/uso terapêutico , Antivirais/uso terapêutico , Infecções por Filoviridae/tratamento farmacológico , Pirazinas/uso terapêutico , Receptores de Interferon/genética , Animais , Modelos Animais de Doenças , Ebolavirus , Feminino , Filoviridae , Técnicas de Inativação de Genes , Doença pelo Vírus Ebola/tratamento farmacológico , Fígado/patologia , Masculino , Doença do Vírus de Marburg/tratamento farmacológico , Marburgvirus , Camundongos , Camundongos Knockout , Estudo de Prova de Conceito , RNA Viral/sangue , Receptores de Interferon/imunologia , Baço/patologia , Virulência
9.
Allergol. immunopatol ; 47(1): 38-42, ene.-feb. 2019. graf
Artigo em Inglês | IBECS | ID: ibc-180769

RESUMO

Introduction: Disseminated BCG infections among other complications of Bacillus Calmette-Guérin (BCG) vaccine are rare and have occurred in children with immunodeficiency disorders such as mendelian susceptibility to mycobacterial disease (MSMD) which could be due to defects in some elements of IL-12/IFN-γ axis. MSMD-causing mutations have been identified in 10 genes during the last two decades. Among them, mutations in the IL12Rβ1 and IFN gamma R1 genes constitute about 80% of recorded cases of MSMD syndrome. The aim of this study was to investigate IL-12RBeta1 and IFN- gammaR1 deficiencies in patients with disseminated BCG infection. Methods: This study was performed on 31 children with disseminated BCG infections who referred to children's medical center. Whole blood cell culture was performed in presence of BCG, IL-12 and IFN- gamma stimulators. The supernatants were assayed for IFN-gamma and IL-12p70 by ELISA method. In order to evaluate IL12Rbeta1 and IFN- gammaR1 receptors expression, flow cytometry staining was performed on the patients’ T-cells stimulated with PHA. Results: Flow cytometry staining of 31 Iranian patients with disseminated BCG infections with the average age of 43 months showed lack of the expression of IL-12RBeta1 and IFN- gamma R1 genes in PHA-T-cells of the nine and one patients, respectively in whom the incomplete production of IFN- gamma and IL-12 was reported by ELISA. Among these 10 patients, eight cases had related parents (80%). Conclusion: It is recommended that to avoid BCG complications, screening be performed for MSMD before BCG inoculation in individuals with positive family history of primary immunodeficiency diseases and inhabitants of areas with high frequency of consanguinity


No disponible


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Vacina BCG/imunologia , Síndromes de Imunodeficiência/epidemiologia , Mutação/genética , Infecções por Mycobacterium/epidemiologia , Receptores de Interferon/genética , Interleucina-12/genética , Linfócitos T/imunologia , Células Cultivadas , Predisposição Genética para Doença , Imunização , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Interferon gama/metabolismo , Interleucina-12/metabolismo , Irã (Geográfico)/epidemiologia , Infecções por Mycobacterium/genética , Infecções por Mycobacterium/imunologia
10.
J Virol ; 93(6)2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30626678

RESUMO

Interferon (IFN) production and the subsequent induction of IFN-stimulated genes (ISGs) are highly effective innate strategies utilized by cells to protect against invading pathogens, including viruses. Critical components involved in this innate process are promyelocytic leukemia nuclear bodies (PML-NBs), which are subnuclear structures required for the development of a robust IFN response. As such, PML-NBs serve as an important hurdle for viruses to overcome to successfully establish an infection. Both Kaposi's sarcoma-associated herpesvirus (KSHV) and the closely related rhesus macaque rhadinovirus (RRV) are unique for encoding viral homologs of IFN regulatory factors (termed vIRFs) that can manipulate the host immune response by multiple mechanisms. All four KSHV vIRFs inhibit the induction of IFN, while vIRF1 and vIRF2 can inhibit ISG induction downstream of the IFN receptor. Less is known about the RRV vIRFs. RRV vIRF R6 can inhibit the induction of IFN by IRF3; however, it is not known whether any RRV vIRFs inhibit ISG induction following IFN receptor signaling. In our present study, we demonstrate that the RRV vIRF R12 aids viral replication in the presence of the type I IFN response. This is achieved in part through the disruption of PML-NBs and the inhibition of robust ISG transcription.IMPORTANCE KSHV and RRV encode a unique set of homologs of cellular IFN regulatory factors, termed vIRFs, which are hypothesized to help these viruses evade the innate immune response and establish infections in their respective hosts. Our work elucidates the role of one RRV vIRF, R12, and demonstrates that RRV can dampen the type I IFN response downstream of IFN signaling, which would be important for establishing a successful infection in vivo.


Assuntos
Fatores Reguladores de Interferon/genética , Interferon Tipo I/genética , Corpos de Inclusão Intranuclear/genética , Leucemia Promielocítica Aguda/genética , Macaca mulatta/virologia , Rhadinovirus/genética , Transdução de Sinais/genética , Proteínas Virais/genética , Animais , Linhagem Celular , Herpesvirus Humano 8/genética , Humanos , Imunidade Inata/genética , Fator Regulador 3 de Interferon/genética , Leucemia Promielocítica Aguda/virologia , Receptores de Interferon/genética , Transcrição Genética/genética , Replicação Viral/genética
11.
Virology ; 526: 155-164, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30390564

RESUMO

IFNγ is a key regulator of inflammatory responses but its role in influenza A virus (IAV) pathogenesis is unclear. Our studies show that infection of mice lacking the IFNγ receptor (IFNγR-/-) at a dose which caused severe disease in wild type 129 Sv/Ev (WT) mice resulted in milder clinical symptoms and significantly lower lung virus titers by 6 days post-infection (dpi). Viral spread was reduced in IFNγR-/- lungs at 2 and 4 dpi. Levels of inflammatory cytokines and chemokines were lower in IFNγR-/- mice at 2 dpi and there was less infiltration of monocyte/macrophage lineage cells than in WT mice. There was no difference in CD4+ and CD8+ T cells and alveolar macrophages in the bronchoalveolar lavage fluid (BALF) at 2 and 4 dpi but by 4 dpi IFNγR-/- mice had significantly higher percentages of neutrophils. Our data strongly suggest that IAV can use the inflammatory response to promote viral spread.


Assuntos
Vírus da Influenza A/patogenicidade , Infecções por Orthomyxoviridae/fisiopatologia , Receptores de Interferon/genética , Transdução de Sinais , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Macrófagos/imunologia , Camundongos , Camundongos Transgênicos , Neutrófilos/imunologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Transdução de Sinais/genética , Carga Viral
12.
Allergol Immunopathol (Madr) ; 47(1): 38-42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30268380

RESUMO

INTRODUCTION: Disseminated BCG infections among other complications of Bacillus Calmette-Guérin (BCG) vaccine are rare and have occurred in children with immunodeficiency disorders such as mendelian susceptibility to mycobacterial disease (MSMD) which could be due to defects in some elements of IL-12/IFN-γ axis. MSMD-causing mutations have been identified in 10 genes during the last two decades. Among them, mutations in the IL12Rß1 and IFNγR1 genes constitute about 80% of recorded cases of MSMD syndrome. The aim of this study was to investigate IL-12Rß1 and IFN-γR1 deficiencies in patients with disseminated BCG infection. METHODS: This study was performed on 31 children with disseminated BCG infections who referred to children's medical center. Whole blood cell culture was performed in presence of BCG, IL-12 and IFN-γ stimulators. The supernatants were assayed for IFN-γ and IL-12p70 by ELISA method. In order to evaluate IL12Rß1 and IFN-γR1 receptors expression, flow cytometry staining was performed on the patients' T-cells stimulated with PHA. RESULTS: Flow cytometry staining of 31 Iranian patients with disseminated BCG infections with the average age of 43 months showed lack of the expression of IL-12Rß1 and IFN-γR1 genes in PHA-T-cells of the nine and one patients, respectively in whom the incomplete production of IFN-γ and IL-12 was reported by ELISA. Among these 10 patients, eight cases had related parents (80%). CONCLUSION: It is recommended that to avoid BCG complications, screening be performed for MSMD before BCG inoculation in individuals with positive family history of primary immunodeficiency diseases and inhabitants of areas with high frequency of consanguinity.


Assuntos
Vacina BCG/imunologia , Síndromes de Imunodeficiência/epidemiologia , Mutação/genética , Infecções por Mycobacterium/epidemiologia , Receptores de Interferon/genética , Receptores de Interleucina-12/genética , Linfócitos T/imunologia , Células Cultivadas , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Humanos , Imunização , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Lactente , Interferon gama/metabolismo , Interleucina-12/metabolismo , Irã (Geográfico)/epidemiologia , Masculino , Infecções por Mycobacterium/genética , Infecções por Mycobacterium/imunologia , Linhagem
13.
Am J Respir Cell Mol Biol ; 60(2): 158-166, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30183325

RESUMO

IFN-λ and IL-22, cytokines that share the coreceptor IL-10RB, are both induced over the course of Klebsiella pneumoniae ST258 (KP35) pneumonia. IL-22 is known to protect mucosal barriers, whereas the effects of IFN-λ on the mucosa are not established. We postulated that IFN-λ plays a role in regulating the airway epithelial barrier to facilitate cellular trafficking to the site of infection. In response to IFN-λ, the transmigration of neutrophils across a polarized monolayer of airway epithelial cells was increased, consistent with diminished epithelial integrity. KP35 infection increased epithelial permeability, and pretreatment with IFN-λ amplified this effect and facilitated bacterial transmigration. These effects of IFN-λ were confirmed in vivo, in that mice lacking the receptor for IFN-λ (Ifnlr1-/-) were protected from bacteremia in a murine model of KP35 pneumonia. Conversely, the integrity of the epithelial barrier was protected by IL-22, with subsequent impairment of neutrophil and bacterial transmigration in vitro. Maximal expression of IL-22 in vivo was observed later in the course of infection than IFN-λ production, with high levels of IL-22 produced by recruited immune cells at 48 hours, consistent with a role in epithelial barrier recovery. The divergent and opposing expression of these two related cytokines suggests a regulated interaction in the host response to KP35 infection. A major physiological effect of IFN-λ signaling is a decrease in epithelial barrier integrity, which facilitates immune cell recruitment but also enables K. pneumoniae invasion.


Assuntos
Interações Hospedeiro-Patógeno/fisiologia , Interferons/metabolismo , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/patogenicidade , Animais , Bacteriemia/genética , Bacteriemia/microbiologia , Brônquios/citologia , Líquido da Lavagem Broncoalveolar/microbiologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Feminino , Humanos , Interferons/farmacologia , Subunidade beta de Receptor de Interleucina-10/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Interleucinas/farmacologia , Klebsiella pneumoniae/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Neutrófilos/microbiologia , Neutrófilos/patologia , Receptores de Interferon/genética , Receptores de Interferon/metabolismo
14.
PLoS Pathog ; 14(11): e1007420, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30485383

RESUMO

It is currently believed that type I and III interferons (IFNs) have redundant functions. However, the preferential distribution of type III IFN receptor on epithelial cells suggests functional differences at epithelial surfaces. Here, using human intestinal epithelial cells we could show that although both type I and type III IFNs confer an antiviral state to the cells, they do so with distinct kinetics. Type I IFN signaling is characterized by an acute strong induction of interferon stimulated genes (ISGs) and confers fast antiviral protection. On the contrary, the slow acting type III IFN mediated antiviral protection is characterized by a weaker induction of ISGs in a delayed manner compared to type I IFN. Moreover, while transcript profiling revealed that both IFNs induced a similar set of ISGs, their temporal expression strictly depended on the IFNs, thereby leading to unique antiviral environments. Using a combination of data-driven mathematical modeling and experimental validation, we addressed the molecular reason for this differential kinetic of ISG expression. We could demonstrate that these kinetic differences are intrinsic to each signaling pathway and not due to different expression levels of the corresponding IFN receptors. We report that type III IFN is specifically tailored to act in specific cell types not only due to the restriction of its receptor but also by providing target cells with a distinct antiviral environment compared to type I IFN. We propose that this specific environment is key at surfaces that are often challenged with the extracellular environment.


Assuntos
Interferon Tipo I/genética , Interferons/genética , Antivirais/farmacologia , Linhagem Celular , Células Epiteliais/metabolismo , Humanos , Interferon Tipo I/metabolismo , Interferons/metabolismo , Interleucinas/metabolismo , Mucosa Intestinal/metabolismo , Receptores de Interferon/genética , Transdução de Sinais/efeitos dos fármacos
15.
J Exp Med ; 215(12): 3057-3074, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30381467

RESUMO

Mechanisms of immune suppression in peripheral tissues counteract protective immunity to prevent immunopathology and are coopted by tumors for immune evasion. While lymphatic vessels facilitate T cell priming, they also exert immune suppressive effects in lymph nodes at steady-state. Therefore, we hypothesized that peripheral lymphatic vessels acquire suppressive mechanisms to limit local effector CD8+ T cell accumulation in murine skin. We demonstrate that nonhematopoietic PD-L1 is largely expressed by lymphatic and blood endothelial cells and limits CD8+ T cell accumulation in tumor microenvironments. IFNγ produced by tissue-infiltrating, antigen-specific CD8+ T cells, which are in close proximity to tumor-associated lymphatic vessels, is sufficient to induce lymphatic vessel PD-L1 expression. Disruption of IFNγ-dependent crosstalk through lymphatic-specific loss of IFNγR boosts T cell accumulation in infected and malignant skin leading to increased viral pathology and tumor control, respectively. Consequently, we identify IFNγR as an immunological switch in lymphatic vessels that balances protective immunity and immunopathology leading to adaptive immune resistance in melanoma.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Derme/imunologia , Interferon gama/imunologia , Vasos Linfáticos/imunologia , Melanoma/imunologia , Proteínas de Neoplasias/imunologia , Neoplasias Cutâneas/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Derme/patologia , Interferon gama/genética , Vasos Linfáticos/patologia , Melanoma/genética , Melanoma/patologia , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/genética , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Neoplasias Cutâneas/patologia
16.
Cell ; 175(5): 1336-1351.e17, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30318148

RESUMO

As a critical step during innate response, the cytoplasmic ß subunit (IFN-γR2) of interferon-γ receptor (IFN-γR) is induced and translocates to plasma membrane to join α subunit to form functional IFN-γR to mediate IFN-γ signaling. However, the mechanism driving membrane translocation and its significance remain largely unknown. We found, unexpectedly, that mice deficient in E-selectin, an endothelial cell-specific adhesion molecule, displayed impaired innate activation of macrophages upon Listeria monocytogenes infection yet had increased circulating IFN-γ. Inflammatory macrophages from E-selectin-deficient mice had less surface IFN-γR2 and impaired IFN-γ signaling. BTK elicited by extrinsic E-selectin engagement phosphorylates cytoplasmic IFN-γR2, facilitating EFhd2 binding and promoting IFN-γR2 trafficking from Golgi to cell membrane. Our findings demonstrate that membrane translocation of cytoplasmic IFN-γR2 is required to activate macrophage innate response against intracellular bacterial infection, identifying the assembly of functional cytokine receptors on cell membrane as an important layer in innate activation and cytokine signaling.


Assuntos
Selectina E/metabolismo , Imunidade Inata , Receptores de Interferon/metabolismo , Animais , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Membrana Celular/metabolismo , Selectina E/deficiência , Selectina E/genética , Complexo de Golgi/metabolismo , Interferon gama/sangue , Interferon gama/metabolismo , Listeria/patogenicidade , Ativação de Macrófagos , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Transporte Proteico , Células RAW 264.7 , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Transdução de Sinais
17.
Viruses ; 10(10)2018 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-30249047

RESUMO

Inflammatory bowel disease (IBD) and Clostridium difficile infection cause gastrointestinal (GI) distension and, in severe cases, toxic megacolon with risk of perforation and death. Herpesviruses have been linked to severe GI dilatation. MHV-68 is a model for human gamma herpesvirus infection inducing GI dilatation in interleukin-10 (IL-10)-deficient mice but is benign in wildtype mice. MHV-68 also causes lethal vasculitis and pulmonary hemorrhage in interferon gamma receptor-deficient (IFNγR-/-) mice, but GI dilatation has not been reported. In prior work the Myxomavirus-derived anti-inflammatory serpin, Serp-1, improved survival, reducing vasculitis and pulmonary hemorrhage in MHV-68-infected IFNγR-/- mice with significantly increased IL-10. IL-10 has been investigated as treatment for GI dilatation with variable efficacy. We report here that MHV-68 infection produces severe GI dilatation with inflammation and gut wall degradation in 28% of INFγR-/- mice. Macrophage invasion and smooth muscle degradation were accompanied by decreased concentrations of T helper (Th2), B, monocyte, and dendritic cells. Plasma and spleen IL-10 were significantly reduced in mice with GI dilatation, while interleukin-1 beta (IL-1ß), IL-6, tumor necrosis factor alpha (TNFα) and INFγ increased. Treatment of gamma herpesvirus-infected mice with exogenous IL-10 prevents severe GI inflammation and dilatation, suggesting benefit for herpesvirus-induced dilatation.


Assuntos
Dilatação Gástrica/terapia , Dilatação Gástrica/virologia , Infecções por Herpesviridae/complicações , Interleucina-10/uso terapêutico , Receptores de Interferon/genética , Rhadinovirus , Animais , Citocinas/sangue , Citocinas/imunologia , Modelos Animais de Doenças , Dilatação Gástrica/genética , Dilatação Gástrica/patologia , Interleucina-10/genética , Camundongos , Camundongos Knockout , Receptores de Interferon/metabolismo , Estatísticas não Paramétricas
18.
Eur J Immunol ; 48(10): 1707-1716, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30051912

RESUMO

Maintaining balanced levels of IL-1ß is extremely important to avoid host tissue damage during infection. Our goal was to understand the mechanisms behind the reduced pathology and decreased bacterial burdens in Ifnlr1-/- mice during lung infection with Staphylococcus aureus. Intranasal infection of Ifnlr1-/- mice with S. aureus led to significantly improved bacterial clearance, survival and decrease of proinflammatory cytokines in the airway including IL-1ß. Ifnlr1-/- mice treated with recombinant IL-1ß displayed increased bacterial burdens in the airway and lung. IL-1ß levels in neutrophils from Ifnlr1-/- infected mice lungs were decreased when compared to neutrophils from WT mice. Mice lacking NLRP3 and caspase-1 had reduced IL-1ß levels 4 h after infection, due to reductions or absence of active caspase-1 respectively, but levels at 24 h were comparable to WT infected mice. Ifnlr1-/- infected mice had decreases in both active caspase-1 and neutrophil elastase indicating an important role for the neutrophil serine protease in IL-1ß processing. By inhibiting neutrophil elastase, we were able to decrease IL-1ß levels by 39% in Nlrp3-/- infected mice when compared to WT mice. These results highlight the crucial role of both proteases in IL-1ß processing, via inflammasome-dependent and -independent mechanisms.


Assuntos
Caspase 1/imunologia , Inflamassomos/imunologia , Interleucina-1beta/imunologia , Elastase de Leucócito/imunologia , Pulmão/imunologia , Infecções Estafilocócicas/imunologia , Animais , Caspase 1/genética , Imunidade Inata , Interleucina-1beta/farmacologia , Elastase de Leucócito/genética , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Neutrófilos/imunologia , Receptores de Interferon/genética , Staphylococcus aureus
19.
J Neuroinflammation ; 15(1): 185, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29907154

RESUMO

BACKGROUND: Macrophages play a key role in peripheral nerve repair and demonstrate complex phenotypes that are highly dependent on microenvironmental cues. METHODS: We determined temporal changes in macrophage gene expression over time using RNA sequencing after fluorescence-activated cell sorting (FACS) macrophage populations from injured peripheral nerve. We identified key upstream regulators and dominant pathways using ingenuity pathway analysis and confirmed these changes with NanoString technology. We then investigate the effects of extreme polarizers of macrophage phenotype (IL4 and IFNγ) on nerve regeneration. We determined macrophage gene expression in vivo at the site of peripheral nerve injury with NanoString technology, and assessed recovery from sciatic nerve injury by cranial tibial muscle weights and retrograde labeling motor neurons in mice with deletion of IL4 or IFNγ receptors. RESULTS: We demonstrate that IL4R and IFNγR deletions provide complementary responses to polarization, and alter expression of genes associated with angiogenesis and axonal extension, but do not influence recovery from peripheral nerve transection at 8 weeks after repair. CONCLUSIONS: Overall, this study provides a framework to evaluate the phenotype of macrophages over time, and provides a broader and more precise assessment of gene expression changes than has previously been commonly used. This data suggests ways in which polarization may be modulated to improve repair.


Assuntos
Regulação da Expressão Gênica/fisiologia , Macrófagos/patologia , Traumatismos dos Nervos Periféricos/patologia , Animais , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Citometria de Fluxo , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular , Interleucina-1/genética , Interleucina-1/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/induzido quimicamente , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Estatísticas não Paramétricas , Fatores de Tempo , Transfecção
20.
Fish Shellfish Immunol ; 79: 140-152, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29742458

RESUMO

Interferon gamma (IFN-γ) is one of the key players in the immune system of vertebrates. The evolution and properties of IFN-γ and its receptors in fish species are of special interest as they point to the origin of innate immunity in vertebrates. We studied the phylogeny, biophysical and structural properties of IFN-γ and its receptors. Our phylogeny analysis suggests the existence of two groups of IFN-γ related proteins, one specific for Acanthomorpha, the other for Cypriniformes, Characiformes and Siluriformes. The analysis further shows an ancient duplication of the gene for IFN-γ receptor 1 (IFN- γR1) and the parallel existence of the duplicated genes in all current teleost fish species. In contrast, only one gene can be found for receptor 2, IFN- γR2. The specificity of the interaction between IFN- γ and both types of IFN- γR1 was determined by microscale thermophoresis measurements of the equilibrium dissociation constants for the proteins from three fish species. The measured preference of IFN- γ for one of the two forms of receptor 1agrees with the bioinformatic analysis of the coevolution between IFN- γ and receptor 1. To elucidate structural relationships between IFN-γ of fish and other vertebrate species, we determined the crystal structure of IFN-γ from olive flounder (Paralichthys olivaceus, PoliIFN-γ) at crystallographic resolution of 2.3 Šand the low-resolution structures of Takifugu rubripes, Oreochromis niloticus, and Larimichthys crocea IFN-γ by small angle X-ray diffraction. The overall PoliIFN-γ fold is the same as the fold of the other known IFN- γ structures but there are some significant structural differences, namely the additional C-terminal helix G and a different angle between helices C and D in PoliIFN-γ.


Assuntos
Evolução Molecular , Peixes/genética , Peixes/imunologia , Interferon gama/genética , Receptores de Interferon/genética , Animais , Interferon gama/metabolismo , Filogenia , Receptores de Interferon/metabolismo
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