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1.
Nature ; 620(7976): 1063-1070, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37587335

RESUMO

High-grade serous ovarian cancers have low survival rates because of their late presentation with extensive peritoneal metastases and frequent chemoresistance1, and require new treatments guided by novel insights into pathogenesis. Here we describe the intrinsic tumour-suppressive activities of interferon-ε (IFNε). IFNε is constitutively expressed in epithelial cells of the fallopian tube, the cell of origin of high-grade serous ovarian cancers, and is then lost during development of these tumours. We characterize its anti-tumour activity in several preclinical models: ovarian cancer patient-derived xenografts, orthotopic and disseminated syngeneic models, and tumour cell lines with or without mutations in Trp53 and Brca genes. We use manipulation of the IFNε receptor IFNAR1 in different cell compartments, differential exposure status to IFNε and global measures of IFN signalling to show that the mechanism of the anti-tumour activity of IFNε involves direct action on tumour cells and, crucially, activation of anti-tumour immunity. IFNε activated anti-tumour T and natural killer cells and prevented the accumulation and activation of myeloid-derived suppressor cells and regulatory T cells. Thus, we demonstrate that IFNε is an intrinsic tumour suppressor in the female reproductive tract whose activities in models of established and advanced ovarian cancer, distinct from other type I IFNs, are compelling indications of potential new therapeutic approaches for ovarian cancer.


Assuntos
Interferon Tipo I , Neoplasias Ovarianas , Proteínas Supressoras de Tumor , Animais , Feminino , Humanos , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Tubas Uterinas/metabolismo , Genes BRCA1 , Genes BRCA2 , Genes p53 , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Células Matadoras Naturais/imunologia , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/metabolismo , Linfócitos T/imunologia , Linfócitos T Reguladores , Proteínas Supressoras de Tumor/imunologia , Proteínas Supressoras de Tumor/metabolismo
2.
Immunol Cell Biol ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862267

RESUMO

Individuals with low socioeconomic status (SES) are at greater risk of contracting and developing severe disease compared with people with higher SES. Age, sex, host genetics, smoking and cytomegalovirus (CMV) serostatus are known to have a major impact on human immune responses and thus susceptibility to infection. However, the impact of SES on immune variability is not well understood or explored. Here, we used data from the Milieu Intérieur project, a study of 1000 healthy volunteers with extensive demographic and biological data, to examine the effect of SES on immune variability. We developed an Elo-rating system using socioeconomic features such as education, income and home ownership status to objectively rank SES in the 1000 donors. We observed sex-specific SES associations, such as females with a low SES having a significantly higher frequency of CMV seropositivity compared with females with high SES, and males with a low SES having a significantly higher frequency of active smoking compared with males with a high SES. Using random forest models, we identified specific immune genes which were significantly associated with SES in both baseline and immune challenge conditions. Interestingly, many of the SES associations were sex stimuli specific, highlighting the complexity of these interactions. Our study provides a new way of computing SES in human populations that can help identify novel SES associations and reinforces biological evidence for SES-dependent susceptibility to infection. This should serve as a basis for further understanding the molecular mechanisms behind SES effects on immune responses and ultimately disease.

3.
Clin Exp Immunol ; 215(2): 177-189, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-37917972

RESUMO

Patients with decompensated liver cirrhosis, in particular those classified as Childs-Pugh class C, are at increased risk of severe coronavirus disease-2019 (COVID-19) upon infection with severe acute respiratory coronavirus 2 (SARS-CoV-2). The biological mechanisms underlying this are unknown. We aimed to examine the levels of serum intrinsic antiviral proteins as well as alterations in the innate antiviral immune response in patients with decompensated liver cirrhosis. Serum from 53 SARS-CoV-2 unexposed and unvaccinated individuals, with decompensated liver cirrhosis undergoing assessment for liver transplantation, were screened using SARS-CoV-2 pseudoparticle and SARS-CoV-2 virus assays. The ability of serum to inhibit interferon (IFN) signalling was assessed using a cell-based reporter assay. Severity of liver disease was assessed using two clinical scoring systems, the Child-Pugh class and the MELD-Na score. In the presence of serum from SARS-CoV-2 unexposed patients with decompensated liver cirrhosis there was no association between SARS-CoV-2 pseudoparticle infection or live SARS-CoV-2 virus infection and severity of liver disease. Type I IFNs are a key component of the innate antiviral response. Serum from patients with decompensated liver cirrhosis contained elevated levels of auto-antibodies capable of binding IFN-α2b compared to healthy controls. High MELD-Na scores were associated with the ability of these auto-antibodies to neutralize type I IFN signalling by IFN-α2b but not IFN-ß1a. Our results demonstrate that neutralizing auto-antibodies targeting IFN-α2b are increased in patients with high MELD-Na scores. The presence of neutralizing type I IFN-specific auto-antibodies may increase the likelihood of viral infections, including severe COVID-19, in patients with decompensated liver cirrhosis.


Assuntos
COVID-19 , Interferon Tipo I , Hepatopatias , Transplante de Fígado , Humanos , Anticorpos , Cirrose Hepática
4.
Sensors (Basel) ; 24(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38931687

RESUMO

Midlife risk factors such as type 2 diabetes mellitus (T2DM) confer a significantly increased risk of cognitive impairment in later life with executive function, memory, and attention domains often affected first. Spatiotemporal gait characteristics are emerging as important integrative biomarkers of neurocognitive function and of later dementia risk. We examined 24 spatiotemporal gait parameters across five domains of gait previously linked to cognitive function on usual-pace, maximal-pace, and cognitive dual-task gait conditions in 102 middle-aged adults with (57.5 ± 8.0 years; 40% female) and without (57.0 ± 8.3 years; 62.1% female) T2DM. Neurocognitive function was measured using a neuropsychological assessment battery. T2DM was associated with significant changes in gait phases and rhythm domains at usual pace, and greater gait variability observed during maximal pace and dual tasks. In the overall cohort, both the gait pace and rhythm domains were associated with memory and executive function during usual pace. At maximal pace, gait pace parameters were associated with reaction time and delayed memory. During the cognitive dual task, associations between gait variability and both delayed memory/executive function were observed. Associations persisted following covariate adjustment and did not differ by T2DM status. Principal components analysis identified a consistent association of slower gait pace (step/stride length) and increased gait variability during maximal-pace walking with poorer memory and executive function performance. These data support the use of spatiotemporal gait as an integrative biomarker of neurocognitive function in otherwise healthy middle-aged individuals and reveal discrete associations between both differing gait tasks and gait domains with domain-specific neuropsychological performance. Employing both maximal-pace and dual-task paradigms may be important in cognitively unimpaired populations with risk factors for later cognitive decline-with the aim of identifying individuals who may benefit from potential preventative interventions.


Assuntos
Diabetes Mellitus Tipo 2 , Marcha , Testes Neuropsicológicos , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Marcha/fisiologia , Diabetes Mellitus Tipo 2/psicologia , Diabetes Mellitus Tipo 2/fisiopatologia , Função Executiva/fisiologia , Cognição/fisiologia , Memória/fisiologia , Idoso
5.
Semin Immunol ; 43: 101328, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31734130

RESUMO

Interferon epsilon (IFNε) is a type I IFN with unusual patterns of expression and therefore, function. It is constitutively expressed by reproductive tract epithelium and regulated by hormones during estrus cycle, reproduction, and menopause and by exogenous hormones. The IFNe protein is encoded by a gene in the type I IFN locus, binds to IFNAR1 and 2 which are required for signaling via the JAK STAT pathway. Its affinity for binding receptors and transducing signals is less potent than IFNα or ß subtypes in vitro. Nevertheless, in vivo experiments indicate its efficacy in regulating mucosal immune responses and protecting from bacterial and viral infections. These studies demonstrate a different mechanism of action to type I IFNs. In this organ system with dynamic fluxes in cellularity, requirement to tolerate an implanted fetus, and be protected from disease, there is co-option of a special IFN from a family of effective immunoregulators, with unique controls and modified potency to make it a safe and effective constitutive reproductive tract cytokine.


Assuntos
Imunidade nas Mucosas , Infecções/imunologia , Interferons/metabolismo , Animais , Implantação do Embrião , Feminino , Humanos , Imunomodulação , Interferon Tipo I/genética , Interferons/genética , Janus Quinases/metabolismo , Ciclo Menstrual , Gravidez , Reprodução , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais
6.
Genes Immun ; 23(2): 93-98, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35428875

RESUMO

The Rhesus D antigen (RhD) has been associated with susceptibility to several viral infections. Reports suggest that RhD-negative individuals are better protected against infectious diseases and have overall better health. However, potential mechanisms contributing to these associations have not yet been defined. Here, we used transcriptomic and genomic data from the Milieu Interieur cohort of 1000 healthy individuals to explore the effect of Rhesus status on the immune response. We used the rs590787 SNP in the RHD gene to classify the 1000 donors as either RhD-positive or -negative. Whole blood was stimulated with LPS, polyIC, and the live influenza A virus and the NanoString human immunology panel of 560 genes used to assess donor immune response and to investigate sex-specific effects. Using regression analysis, we observed no significant differences in responses to polyIC or LPS between RhD-positive and -negative individuals. However, upon sex-specific analysis, we observed over 40 differentially expressed genes (DEGs) between RhD-positive (n = 384) and RhD-negative males (n = 75) after influenza virus stimulation. Interestingly these Rhesus-associated differences were not seen in females. Further investigation, using gene set enrichment analysis, revealed enhanced IFNγ signalling in RhD-negative males. This amplified IFNγ signalling axis may explain the increased viral resistance previously described in RhD-negative individuals.


Assuntos
Vírus da Influenza A , Feminino , Humanos , Imunidade , Lipopolissacarídeos , Masculino
7.
Sensors (Basel) ; 22(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35957266

RESUMO

Type 2 Diabetes Mellitus (T2DM) in midlife is associated with a greater risk of dementia in later life. Both gait speed and spatiotemporal gait characteristics have been associated with later cognitive decline in community-dwelling older adults. Thus, the assessment of gait characteristics in uncomplicated midlife T2DM may be important in selecting-out those with T2DM at greatest risk of later cognitive decline. We assessed the relationship between Inertial Motion Unit (IMUs)-derived gait characteristics and cognitive function assessed via Montreal Cognitive Assessment (MoCA)/detailed neuropsychological assessment battery (CANTAB) in middle-aged adults with and without uncomplicated T2DM using both multivariate linear regression and a neural network approach. Gait was assessed under (i) normal walking, (ii) fast (maximal) walking and (iii) cognitive dual-task walking (reciting alternate letters of the alphabet) conditions. Overall, 138 individuals were recruited (n = 94 with T2DM; 53% female, 52.8 ± 8.3 years; n = 44 healthy controls, 43% female, 51.9 ± 8.1 years). Midlife T2DM was associated with significantly slower gait velocity on both slow and fast walks (both p < 0.01) in addition to a longer stride time and greater gait complexity during normal walk (both p < 0.05). Findings persisted following covariate adjustment. In analyzing cognitive performance, the strongest association was observed between gait velocity and global cognitive function (MoCA). Significant associations were also observed between immediate/delayed memory performance and gait velocity. Analysis using a neural network approach did not outperform multivariate linear regression in predicting cognitive function (MoCA) from gait velocity. Our study demonstrates the impact of uncomplicated T2DM on gait speed and gait characteristics in midlife, in addition to the striking relationship between gait characteristics and global cognitive function/memory performance in midlife. Further studies are needed to evaluate the longitudinal relationship between midlife gait characteristics and later cognitive decline, which may aid in selecting-out those with T2DM at greatest-risk for preventative interventions.


Assuntos
Diabetes Mellitus Tipo 2 , Idoso , Cognição , Feminino , Marcha , Humanos , Masculino , Pessoa de Meia-Idade , Caminhada , Velocidade de Caminhada
8.
J Immunol ; 202(8): 2384-2396, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30787108

RESUMO

MyD88 adaptor-like (Mal) protein is the most polymorphic of the four key adaptor proteins involved in TLR signaling. TLRs play a critical role in the recognition and immune response to pathogens through activation of the prototypic inflammatory transcription factor NF-κB. The study of single nucleotide polymorphisms in TLRs, adaptors, and signaling mediators has provided key insights into the function of the corresponding genes but also into the susceptibility to infectious diseases in humans. In this study, we have analyzed the immune response of mice carrying the human Mal-D96N genetic variation that has previously been proposed to confer protection against septic shock. We have found that Mal-D96N macrophages display reduced cytokine expression in response to TLR4 and TLR2 ligand challenge. Mal-D96N macrophages also display reduced MAPK activation, NF-κB transactivation, and delayed NF-κB nuclear translocation, presumably via delayed kinetics of Mal interaction with MyD88 following LPS stimulation. Importantly, Mal-D96N genetic variation confers a physiological protective phenotype to in vivo models of LPS-, Escherichia coli-, and influenza A virus-induced hyperinflammatory disease in a gene dosage-dependent manner. Together, these results highlight the critical role Mal plays in regulating optimal TLR-induced inflammatory signaling pathways and suggest the potential therapeutic advantages of targeting the Mal D96 signaling nexus.


Assuntos
Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases , Macrófagos/imunologia , Mutação de Sentido Incorreto , Fator 88 de Diferenciação Mieloide , Polimorfismo de Nucleotídeo Único , Receptores Toll-Like , Substituição de Aminoácidos , Animais , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/imunologia , Camundongos , Camundongos Mutantes , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia
9.
Cell Mol Life Sci ; 75(5): 775-783, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28988399

RESUMO

Viral infections, including HIV, trigger the production of type I interferons (IFNs), which in turn, activate a signalling cascade that ultimately culminates with the expression of anti-viral proteins. Mounting evidence suggests that type I IFNs, in particular IFN-α, play a pivotal role in limiting acute HIV infection. Highly active anti-retroviral treatment reduces viral load and increases life expectancy in HIV positive patients; however, it fails to fully eliminate latent HIV reservoirs. To revisit HIV as a curable disease, this article reviews a body of literature that highlights type I IFNs as mediators in the control of HIV infection, with particular focus on the anti-HIV restriction factors induced and/or activated by IFN-α. In addition, we discuss the relevance of type I IFN treatment in the context of HIV latency reversal, novel therapeutic intervention strategies and the potential for full HIV clearance.


Assuntos
Infecções por HIV/tratamento farmacológico , HIV/efeitos dos fármacos , HIV/fisiologia , Interferon-alfa/uso terapêutico , Latência Viral/efeitos dos fármacos , Infecções por HIV/virologia , Humanos , Interferon-alfa/farmacologia , Indução de Remissão/métodos , Carga Viral/efeitos dos fármacos , Latência Viral/fisiologia
10.
J Biol Chem ; 292(18): 7554-7565, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28289093

RESUMO

The interaction of IFN-ß with its receptor IFNAR1 (interferon α/ß receptor subunit 1) is vital for host-protective anti-viral and anti-proliferative responses, but signaling via this interaction can be detrimental if dysregulated. Whereas it is established that IFNAR1 is an essential component of the IFNAR signaling complex, the key residues underpinning the IFN-ß-IFNAR1 interaction are unknown. Guided by the crystal structure of the IFN-ß-IFNAR1 complex, we used truncation variants and site-directed mutagenesis to investigate domains and residues enabling complexation of IFN-ß to IFNAR1. We have identified an interface on IFNAR1-subdomain-3 that is differentially utilized by IFN-ß and IFN-α for signal transduction. We used surface plasmon resonance and cell-based assays to investigate this important IFN-ß binding interface that is centered on IFNAR1 residues Tyr240 and Tyr274 binding the C and N termini of the B and C helices of IFN-ß, respectively. Using IFNAR1 and IFN-ß variants, we show that this interface contributes significantly to the affinity of IFN-ß for IFNAR1, its ability to activate STAT1, the expression of interferon stimulated genes, and ultimately to the anti-viral and anti-proliferative properties of IFN-ß. These results identify a key interface created by IFNAR1 residues Tyr240 and Tyr274 interacting with IFN-ß residues Phe63, Leu64, Glu77, Thr78, Val81, and Arg82 that underlie IFN-ß-IFNAR1-mediated signaling and biological processes.


Assuntos
Interferon beta/metabolismo , Receptor de Interferon alfa e beta/metabolismo , Transdução de Sinais/fisiologia , Substituição de Aminoácidos , Animais , Linhagem Celular , Interferon beta/genética , Camundongos , Camundongos Knockout , Mutação de Sentido Incorreto , Domínios Proteicos , Receptor de Interferon alfa e beta/genética
11.
Cell Mol Life Sci ; 74(9): 1755-1764, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27988795

RESUMO

The cytokine, Interferon (IFN)-α, induces a wide spectrum of anti-viral mediators, via the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. STAT1 and STAT2 are well characterised to upregulate IFN-stimulated gene (ISG) expression; but even though STAT3 is also activated by IFN-α, its role in anti-viral ISG induction is unclear. Several viruses, including Hepatitis C and Mumps, reduce cellular STAT3 protein levels, via the promotion of ubiquitin-mediated proteasomal degradation. This viral immune evasion mechanism suggests an undiscovered anti-viral role for STAT3 in IFN-α signalling. To investigate STAT3's functional involvement in this Type I IFN pathway, we first analysed its effect upon the replication of two viruses, Influenza and Vaccinia. Viral plaque assays, using Wild Type (WT) and STAT3-/- Murine Embryonic Fibroblasts (MEFs), revealed that STAT3 is required for the inhibition of Influenza and Vaccinia replication. Furthermore, STAT3 shRNA knockdown also enhanced Influenza replication and hindered induction of several, well characterised, anti-viral ISGs: PKR, OAS2, MxB and ISG15; while STAT3 expression had no effect upon induction of a separate ISG group: Viperin, IFI27, CXCL10 and CCL5. These discoveries reveal, for the first time, an anti-viral role for STAT3 in the IFN-α pathway and characterise a requirement for STAT3 in the expression of specific ISGs. These findings also identify STAT3 as a therapeutic target against viral infection and highlight it as an essential pathway component for endogenous and therapeutic IFN-α responsiveness.


Assuntos
Interferon-alfa/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , 2',5'-Oligoadenilato Sintetase/metabolismo , Animais , Linhagem Celular , Técnicas de Silenciamento de Genes , Humanos , Vírus da Influenza A/fisiologia , Camundongos , Proteínas de Resistência a Myxovirus , Vaccinia virus/fisiologia , eIF-2 Quinase/metabolismo
12.
J Biol Chem ; 289(10): 6429-6437, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24407287

RESUMO

The apoptosis-associated speck-like protein containing a caspase-activating recruitment domain (ASC) is an essential component of several inflammasomes, multiprotein complexes that regulate caspase-1 activation and inflammation. We report here an interaction between promyelocytic leukemia protein (PML) and ASC. We observed enhanced formation of ASC dimers in PML-deficient macrophages. These macrophages also display enhanced levels of ASC in the cytosol. Furthermore, IL-1ß production was markedly enhanced in these macrophages in response to both NLRP3 and AIM2 inflammasome activation and following bone marrow-derived macrophage infection with herpes simplex virus-1 (HSV-1) and Salmonella typhimurium. Collectively, our data indicate that PML limits ASC function, retaining ASC in the nucleus.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Inflamassomos/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proteínas do Citoesqueleto/genética , Citosol/metabolismo , Proteínas de Ligação a DNA , Células HEK293 , Humanos , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteínas Nucleares/genética , Proteína da Leucemia Promielocítica , Multimerização Proteica , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética
13.
J Transl Med ; 12: 206, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-25048205

RESUMO

BACKGROUND: Treatment with interferon-alpha (IFN-α) and ribavirin successfully clears hepatitis C virus (HCV) infection in 50% of patients infected with genotype 1. Addition of NS3-4A protease inhibitors (PIs) increases response rates but results in additional side effects and significant economic costs. Here, we hypothesised that in vitro responsiveness of peripheral blood mononuclear cells (PBMCs) to IFN-α stimulation would identify patients who achieved sustained virological response (SVR) on dual therapy alone and thus not require addition of PIs. METHODS: PBMCs were isolated from HCV infected patients (n = 42), infected with either HCV genotype 1 or genotype 3, before commencing therapy and stimulated in vitro with IFN-α. Expression of the IFN stimulated genes (ISGs) PKR, OAS and MxA was measured and correlated with subsequent treatment response and IL28B genotype. RESULTS: Genotype 1 infected patients who achieved SVR had significantly higher pre-treatment expression of PKR (p = 0.0148), OAS (p = 0.0019) and MxA (p = 0.0019) in IFN-α stimulated PBMCs, compared to genotype 1 infected patients who did not achieve SVR or patients infected with genotype 3, whose in vitro ISG expression did not correlate with clinical responsiveness. IL28B genotype (rs12979860) did not correlate with endogenous or IFN-α stimulated ISG responsiveness. CONCLUSIONS: In vitro responsiveness of PBMCs to IFN-α from genotype 1 infected patients predicts clinical responsiveness to dual therapy, independently of IL28B genotype. These results indicate that this sub-group of HCV infected patients could be identified pre-treatment and successfully treated without PIs, thus reducing adverse side effects and emergence of PI resistant virus while making significant economic savings.


Assuntos
Células Sanguíneas/virologia , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/uso terapêutico , Interleucinas/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Células Sanguíneas/efeitos dos fármacos , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Humanos , Interferon-alfa/farmacologia , Interferons , Masculino , Polimorfismo de Nucleotídeo Único/genética , Resultado do Tratamento
14.
Mol Cell Biol ; : 1-10, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975675

RESUMO

Interferon epsilon (IFNε) is a unique type I interferon (IFN) that shows distinct constitutive expression in reproductive tract epithelium. Understanding how IFNε expression is regulated is critical for the mechanism of action in protecting the mucosa from infection. Combined computational and experimental investigation of the promoter of IFNε predicted transcription factor binding sites for the ETS family of transcription factors. We demonstrate here that Ifnε is regulated by Elf3, an epithelial restricted member of the ETS family. It is co-expressed with IFNε at the epithelium of uterus, lung and intestine, and we focused on regulation of IFNε expression in the uterus. Promoter reporter studies demonstrated that Elf3 was a strong driver of Ifnε expression; knockdown of Elf3 reduced expression levels of IFNε; Elf3 regulated Ifnε expression and chromatin immunoprecipitation (ChIP) confirmed the direct binding of Elf3 to the IFNε promoter. These data show that Elf3 is important in regulating protective mucosal immunity by driving constitutive expression of IFNε to protect mucosal tissues from infection in at least three organ systems.

15.
PLoS Pathog ; 7(9): e1002247, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21931555

RESUMO

Recognition of viruses by pattern recognition receptors (PRRs) causes interferon-ß (IFN-ß) induction, a key event in the anti-viral innate immune response, and also a target of viral immune evasion. Here the vaccinia virus (VACV) protein C6 is identified as an inhibitor of PRR-induced IFN-ß expression by a functional screen of select VACV open reading frames expressed individually in mammalian cells. C6 is a member of a family of Bcl-2-like poxvirus proteins, many of which have been shown to inhibit innate immune signalling pathways. PRRs activate both NF-κB and IFN regulatory factors (IRFs) to activate the IFN-ß promoter induction. Data presented here show that C6 inhibits IRF3 activation and translocation into the nucleus, but does not inhibit NF-κB activation. C6 inhibits IRF3 and IRF7 activation downstream of the kinases TANK binding kinase 1 (TBK1) and IκB kinase-ε (IKKε), which phosphorylate and activate these IRFs. However, C6 does not inhibit TBK1- and IKKε-independent IRF7 activation or the induction of promoters by constitutively active forms of IRF3 or IRF7, indicating that C6 acts at the level of the TBK1/IKKε complex. Consistent with this notion, C6 immunoprecipitated with the TBK1 complex scaffold proteins TANK, SINTBAD and NAP1. C6 is expressed early during infection and is present in both nucleus and cytoplasm. Mutant viruses in which the C6L gene is deleted, or mutated so that the C6 protein is not expressed, replicated normally in cell culture but were attenuated in two in vivo models of infection compared to wild type and revertant controls. Thus C6 contributes to VACV virulence and might do so via the inhibition of PRR-induced activation of IRF3 and IRF7.


Assuntos
Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 7 de Interferon/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Vaccinia virus/genética , Proteínas Virais/genética , Regulação Viral da Expressão Gênica , Genes Reguladores , Células HEK293 , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Evasão da Resposta Imune , Imunidade Inata , Fator Regulador 3 de Interferon/genética , Fator Regulador 7 de Interferon/genética , Interferon beta/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Fases de Leitura Aberta , Fosforilação , Plasmídeos , Ligação Proteica/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Reconhecimento de Padrão/metabolismo , Transdução de Sinais , Transcrição Gênica , Vaccinia virus/metabolismo , Vaccinia virus/fisiologia , Proteínas Virais/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Replicação Viral
16.
PLoS One ; 18(6): e0287169, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37379302

RESUMO

Research studies have observed associations of vitamin D with inflammation but data in representative older adult studies is lacking. We aimed to investigate the association of C-reactive protein (CRP) with vitamin D status in a representative sample of the older Irish population. The concentrations of 25-hydroxyvitamin D (25(OH)D) and CRP was measured in 5,381 community dwelling Irish adults aged ≥50 years from the Irish Longitudinal Study on Ageing (TILDA). Demographic, health and lifestyle variables were assessed by questionnaire and categorical proportions of CRP were generated by vitamin D status and age. Multi-nominal logistic regression was used to investigate the association of 25(OH)D and CRP status. The prevalence (mean; 95% confidence interval (95% CI)) of normal CRP status (0-5 mg/dL) was 83.9% (82.6-85.0%), elevated status (5-10 mg/dL) 11.0% (9.9-12.0%) and high status (>10 mg/dL) was 5.1% (4.5-5.8%). Mean (95% CI) CRP concentrations were lower in those with normal vs. deficient 25(OH)D status (2.02 mg/dL (1.95-2.08) vs. 2.60 mg/dL (2.41-2.82); p<0.0001). In a logistic regression analysis, those with insufficient or sufficient 25(OH)D status were less likely to have a high CRP status compared to those with deficient 25(OH)D status (insufficient: coefficient (CE) -0.732, 95% CI -1.12-0.33, p<0.0001; sufficient: CE -0.599, 95% CI -0.95-0.24, p = 0.001). In conclusion older adults with deficient vitamin D status had higher levels of inflammation as measured by CRP. Given that inflammation is an important pathological driver of chronic diseases of ageing, and that emerging evidence suggests that vitamin D therapy can reduce inflammation in some disease settings, optimising vitamin D status could represent an effective low risk/low-cost pathway to modulate inflammation in community dwelling older adults.


Assuntos
Deficiência de Vitamina D , Vitamina D , Humanos , Idoso , Estudos Longitudinais , Vitaminas , Inflamação , Calcifediol , Proteína C-Reativa/metabolismo , Deficiência de Vitamina D/epidemiologia
17.
Front Immunol ; 14: 1170012, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063871

RESUMO

Clinical outcomes from infection with SARS-CoV-2, the cause of the COVID-19 pandemic, are remarkably variable ranging from asymptomatic infection to severe pneumonia and death. One of the key drivers of this variability is differing trajectories in the immune response to SARS-CoV-2 infection. Many studies have noted markedly elevated cytokine levels in severe COVID-19, although results vary by cohort, cytokine studied and sensitivity of assay used. We assessed the immune response in acute COVID-19 by measuring 20 inflammatory markers in 118 unvaccinated patients with acute COVID-19 (median age: 70, IQR: 58-79 years; 48.3% female) recruited during the first year of the pandemic and 44 SARS-CoV-2 naïve healthy controls. Acute COVID-19 was associated with marked elevations in nearly all pro-inflammatory markers, whilst eleven markers (namely IL-1ß, IL-2, IL-6, IL-10, IL-18, IL-23, IL-33, TNF-α, IP-10, G-CSF and YKL-40) were associated with disease severity. We observed significant correlations between nearly all markers elevated in those infected with SARS-CoV-2 consistent with widespread immune dysregulation. Principal component analysis highlighted a pro-inflammatory cytokine signature (with strongest contributions from IL-1ß, IL-2, IL-6, IL-10, IL-33, G-CSF, TNF-α and IP-10) which was independently associated with severe COVID-19 (aOR: 1.40, 1.11-1.76, p=0.005), invasive mechanical ventilation (aOR: 1.61, 1.19-2.20, p=0.001) and mortality (aOR 1.57, 1.06-2.32, p = 0.02). Our findings demonstrate elevated cytokines and widespread immune dysregulation in severe COVID-19, adding further evidence for the role of a pro-inflammatory cytokine signature in severe and critical COVID-19.


Assuntos
COVID-19 , Humanos , Feminino , Idoso , Masculino , Citocinas , Interleucina-10 , Interleucina-33 , SARS-CoV-2 , Interleucina-6 , Fator de Necrose Tumoral alfa , Pandemias , Quimiocina CXCL10 , Interleucina-2 , Fator Estimulador de Colônias de Granulócitos
18.
BMJ Open ; 13(12): e077772, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38070888

RESUMO

INTRODUCTION: Alzheimer's disease and other dementias affect >50 million individuals globally and are characterised by broad clinical and biological heterogeneity. Cohort and biobank studies have played a critical role in advancing the understanding of disease pathophysiology and in identifying novel diagnostic and treatment approaches. However, further discovery and validation cohorts are required to clarify the real-world utility of new biomarkers, facilitate research into the development of novel therapies and advance our understanding of the clinical heterogeneity and pathobiology of neurodegenerative diseases. METHODS AND ANALYSIS: The Tallaght University Hospital Institute for Memory and Cognition Biobank for Research in Ageing and Neurodegeneration (TIMC-BRAiN) will recruit 1000 individuals over 5 years. Participants, who are undergoing diagnostic workup in the TIMC Memory Assessment and Support Service (TIMC-MASS), will opt to donate clinical data and biological samples to a biobank. All participants will complete a detailed clinical, neuropsychological and dementia severity assessment (including Addenbrooke's Cognitive Assessment, Repeatable Battery for Assessment of Neuropsychological Status, Clinical Dementia Rating Scale). Participants undergoing venepuncture/lumbar puncture as part of the clinical workup will be offered the opportunity to donate additional blood (serum/plasma/whole blood) and cerebrospinal fluid samples for longitudinal storage in the TIMC-BRAiN biobank. Participants are followed at 18-month intervals for repeat clinical and cognitive assessments. Anonymised clinical data and biological samples will be stored securely in a central repository and used to facilitate future studies concerned with advancing the diagnosis and treatment of neurodegenerative diseases. ETHICS AND DISSEMINATION: Ethical approval has been granted by the St. James's Hospital/Tallaght University Hospital Joint Research Ethics Committee (Project ID: 2159), which operates in compliance with the European Communities (Clinical Trials on Medicinal Products for Human Use) Regulations 2004 and ICH Good Clinical Practice Guidelines. Findings using TIMC-BRAiN will be published in a timely and open-access fashion.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Humanos , Bancos de Espécimes Biológicos , Doença de Alzheimer/diagnóstico , Envelhecimento , Cognição , Doenças Neurodegenerativas/diagnóstico , Hospitais , Disfunção Cognitiva/diagnóstico
19.
J Am Med Dir Assoc ; 23(9): 1590-1602, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35922016

RESUMO

Older adults in nursing homes are at greatest risk of morbidity and mortality from SARS-CoV-2 infection. Nursing home residents constituted one-third to more than half of all deaths during the early waves of the COVID-19 pandemic. Following this, widespread adaptation of infection prevention and control measures and the supply and use of personal protective equipment resulted in a significant decrease in nursing home infections and deaths. For nursing homes, the most important determinant of experiencing a SARS-CoV-2 outbreak in the first instance appears to be community-transmission levels (particularly with variants of concern), although nursing home size and quality, for-profit status, and sociodemographic characteristics are also important. Use of visitation bans, imposed to reduce the impact of COVID-19 on residents, must be delicately balanced against their impact on resident, friend or family, and staff well-being. The successful rollout of primary vaccination has resulted in a sharp decrease in morbidity and mortality from SARS-CoV-2 in nursing homes. However, emerging evidence suggests that vaccine efficacy may wane over time, and the use of a third or additional vaccine "booster" doses in nursing home residents restores protection afforded by primary vaccination. Ongoing monitoring of vaccine efficacy in terms of infection, morbidity, and mortality is crucial in this vulnerable group in informing ongoing SARS-CoV-2 vaccine boosting strategies. Here, we detail the impact of SARS-CoV-2 on nursing home residents and discuss important considerations in the management of nursing home SARS-CoV-2 outbreaks. We additionally examine the use of testing strategies, nonpharmacologic outbreak control measures and vaccination strategies in this cohort. Finally, the impact of SARS-CoV-2 on the sector is reflected on as we emphasize the need for adoption of universal standards of medical care and integration with wider public health infrastructure in nursing homes in order to provide a safe and effective long-term care sector.


Assuntos
COVID-19 , Idoso , Vacinas contra COVID-19 , Humanos , Assistência de Longa Duração , Casas de Saúde , Pandemias/prevenção & controle , SARS-CoV-2
20.
Cell Rep Med ; 3(11): 100804, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36334594

RESUMO

Natural resistance to infection is an overlooked outcome after hepatitis C virus (HCV) exposure. Between 1977 and 1979, 1,200 Rhesus D-negative Irish women were exposed to HCV-contaminated anti-D immunoglobulin. Here, we investigate why some individuals appear to resist infection despite exposure (exposed seronegative [ESN]). We screen HCV-resistant and -susceptible donors for anti-HCV adaptive immune responses using ELISpots and VirScan to profile antibodies against all know human viruses. We perform standardized ex vivo whole blood stimulation (TruCulture) assays with antiviral ligands and assess antiviral responses using NanoString transcriptomics and Luminex proteomics. We describe an enhanced TLR3-type I interferon response in ESNs compared with seropositive women. We also identify increased inflammatory cytokine production in response to polyIC in ESNs compared with seropositive women. These enhanced responses may have contributed to innate immune protection against HCV infection in our cohort.


Assuntos
Hepacivirus , Hepatite C , Humanos , Feminino , Receptor 3 Toll-Like/genética , Hepatite C/tratamento farmacológico , Antivirais
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