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1.
Front Cell Infect Microbiol ; 11: 638852, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816341

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged in December 2019 and rapidly outspread worldwide endangering human health. The coronavirus disease 2019 (COVID-19) manifests itself through a wide spectrum of symptoms that can evolve to severe presentations as pneumonia and several non-respiratory complications. Increased susceptibility to COVID-19 hospitalization and mortality have been linked to associated comorbidities as diabetes, hypertension, cardiovascular diseases and, recently, to obesity. Similarly, individuals living with obesity are at greater risk to develop clinical complications and to have poor prognosis in severe influenza pneumonia. Immune and metabolic dysfunctions associated with the increased susceptibility to influenza infection are linked to obesity-associated low-grade inflammation, compromised immune and endocrine systems, and to high cardiovascular risk. These preexisting conditions may favor virological persistence, amplify immunopathological responses and worsen hemodynamic instability in severe COVID-19 as well. In this review we highlight the main factors and the current state of the art on obesity as risk factor for influenza and COVID-19 hospitalization, severe respiratory manifestations, extrapulmonary complications and even death. Finally, immunoregulatory mechanisms of severe influenza pneumonia in individuals with obesity are addressed as likely factors involved in COVID-19 pathophysiology.


Assuntos
Peso Corporal , Imunidade , Influenza Humana/imunologia , Obesidade/imunologia , Adipocinas , Tecido Adiposo , Animais , Comorbidade , Diabetes Mellitus , Endotoxemia , Hospitalização , Humanos , Hiperglicemia , Inflamação , Influenza Humana/fisiopatologia , Síndrome Metabólica , Obesidade/complicações , Infecções por Orthomyxoviridae/imunologia , Fatores de Risco
2.
Nat Commun ; 12(1): 1914, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772013

RESUMO

Innate immunity is important for host defense by eliciting rapid anti-viral responses and bridging adaptive immunity. Here, we show that endogenous lipids released from virus-infected host cells activate lung γδ T cells to produce interleukin 17 A (IL-17A) for early protection against H1N1 influenza infection. During infection, the lung γδ T cell pool is constantly supplemented by thymic output, with recent emigrants infiltrating into the lung parenchyma and airway to acquire tissue-resident feature. Single-cell studies identify IL-17A-producing γδ T (Tγδ17) cells with a phenotype of TCRγδhiCD3hiAQP3hiCXCR6hi in both infected mice and patients with pneumonia. Mechanistically, host cell-released lipids during viral infection are presented by lung infiltrating CD1d+ B-1a cells to activate IL-17A production in γδ T cells via γδTCR-mediated IRF4-dependent transcription. Reduced IL-17A production in γδ T cells is detected in mice either lacking B-1a cells or with ablated CD1d in B cells. Our findings identify a local host-immune crosstalk and define important cellular and molecular mediators for early innate defense against lung viral infection.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Lipídeos/imunologia , Infecções por Orthomyxoviridae/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Animais , Antígenos CD1d/imunologia , Antígenos CD1d/metabolismo , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/imunologia , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/metabolismo , Influenza Humana/virologia , Fatores Reguladores de Interferon/imunologia , Fatores Reguladores de Interferon/metabolismo , Interleucina-17/imunologia , Interleucina-17/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo
3.
Nat Commun ; 12(1): 1203, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33619277

RESUMO

Influenza A virus infection in swine impacts the agricultural industry in addition to its zoonotic potential. Here, we utilize epigraph, a computational algorithm, to design a universal swine H3 influenza vaccine. The epigraph hemagglutinin proteins are delivered using an Adenovirus type 5 vector and are compared to a wild type hemagglutinin and the commercial inactivated vaccine, FluSure. In mice, epigraph vaccination leads to significant cross-reactive antibody and T-cell responses against a diverse panel of swH3 isolates. Epigraph vaccination also reduces weight loss and lung viral titers in mice after challenge with three divergent swH3 viruses. Vaccination studies in swine, the target species for this vaccine, show stronger levels of cross-reactive antibodies and T-cell responses after immunization with the epigraph vaccine compared to the wild type and FluSure vaccines. In both murine and swine models, epigraph vaccination shows superior cross-reactive immunity that should be further investigated as a universal swH3 vaccine.


Assuntos
Algoritmos , Reações Cruzadas/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Imunidade , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Animais , Formação de Anticorpos/imunologia , Epitopos/imunologia , Feminino , Humanos , Influenza Humana/sangue , Influenza Humana/imunologia , Influenza Humana/virologia , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/sangue , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Suínos , Linfócitos T/imunologia , Vacinação , Perda de Peso
4.
J Virol ; 95(9)2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33627390

RESUMO

Current influenza vaccines, live attenuated or inactivated, do not protect against antigenically novel influenza A viruses (IAVs) of pandemic potential, which has driven interest in the development of universal influenza vaccines. Universal influenza vaccine candidates targeting highly conserved antigens of IAV nucleoprotein (NP) are promising as vaccines that induce T cell immunity, but concerns have been raised about the safety of inducing robust CD8 T cell responses in the lungs. Using a mouse model, we systematically evaluated effects of recombinant adenovirus vectors (rAd) expressing IAV NP (A/NP-rAd) or influenza B virus (IBV) NP (B/NP-rAd) on pulmonary inflammation and function after vaccination and following live IAV challenge. After A/NP-rAd or B/NP-rAd vaccination, female mice exhibited robust systemic and pulmonary vaccine-specific B cell and T cell responses and experienced no morbidity (e.g., body mass loss). Both in vivo pulmonary function testing and lung histopathology scoring revealed minimal adverse effects of intranasal rAd vaccination compared with unvaccinated mice. After IAV challenge, A/NP-rAd-vaccinated mice experienced significantly less morbidity, had lower pulmonary virus titers, and developed less pulmonary inflammation than unvaccinated or B/NP-rAd-vaccinated mice. Based on analysis of pulmonary physiology using detailed testing not previously applied to the question of T cell damage, mice protected by vaccination also had better lung function than controls. Results provide evidence that, in this model, adenoviral universal influenza vaccine does not damage pulmonary tissue. In addition, adaptive immunity, in particular, T cell immunity in the lungs, does not cause damage when restimulated but instead mitigates pulmonary damage following IAV infection.IMPORTANCE Respiratory viruses can emerge and spread rapidly before vaccines are available. It would be a tremendous advance to use vaccines that protect against whole categories of viruses, such as universal influenza vaccines, without the need to predict which virus will emerge. The nucleoprotein (NP) of influenza virus provides a target conserved among strains and is a dominant T cell target. In animals, vaccination to NP generates powerful T cell immunity and long-lasting protection against diverse influenza strains. Concerns have been raised, but not evaluated experimentally, that potent local T cell responses might damage the lungs. We analyzed lung function in detail in the setting of such a vaccination. Despite CD8 T cell responses in the lungs, lungs were not damaged and functioned normally after vaccination alone and were protected upon subsequent infection. This precedent provides important support for vaccines based on T cell-mediated protection, currently being considered for both influenza and SARS-CoV-2 vaccines.


Assuntos
Adenoviridae , Vetores Genéticos , Vírus da Influenza B , Vacinas contra Influenza , Pulmão , Infecções por Orthomyxoviridae , Adenoviridae/genética , Adenoviridae/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/patologia , Modelos Animais de Doenças , Feminino , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Imunidade Celular , Vírus da Influenza B/genética , Vírus da Influenza B/imunologia , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Camundongos , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/prevenção & controle , Linfócitos T/imunologia , Linfócitos T/patologia
5.
EMBO J ; 40(6): e105543, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33586810

RESUMO

Influenza A virus (IAV) and SARS-CoV-2 (COVID-19) cause pandemic infections where cytokine storm syndrome and lung inflammation lead to high mortality. Given the high social and economic cost of respiratory viruses, there is an urgent need to understand how the airways defend against virus infection. Here we use mice lacking the WD and linker domains of ATG16L1 to demonstrate that ATG16L1-dependent targeting of LC3 to single-membrane, non-autophagosome compartments - referred to as non-canonical autophagy - protects mice from lethal IAV infection. Mice with systemic loss of non-canonical autophagy are exquisitely sensitive to low-pathogenicity IAV where extensive viral replication throughout the lungs, coupled with cytokine amplification mediated by plasmacytoid dendritic cells, leads to fulminant pneumonia, lung inflammation and high mortality. IAV was controlled within epithelial barriers where non-canonical autophagy reduced IAV fusion with endosomes and activation of interferon signalling. Conditional mouse models and ex vivo analysis showed that protection against IAV infection of lung was independent of phagocytes and other leucocytes. This establishes non-canonical autophagy in airway epithelial cells as a novel innate defence that restricts IAV infection and lethal inflammation at respiratory surfaces.


Assuntos
Proteínas Relacionadas à Autofagia/genética , Vírus da Influenza A/patogenicidade , Proteínas Associadas aos Microtúbulos/metabolismo , Infecções por Orthomyxoviridae/genética , Deleção de Sequência , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/virologia , Animais , Autofagia , Proteínas Relacionadas à Autofagia/química , Proteínas Relacionadas à Autofagia/metabolismo , Embrião de Galinha , Citocinas/metabolismo , Cães , Células Madin Darby de Rim Canino , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/mortalidade , Domínios Proteicos , Replicação Viral
6.
Arch Virol ; 166(2): 545-557, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33409549

RESUMO

The use of gamma-irradiated influenza A virus (γ-Flu), retains most of the viral structural antigens, represent a promising option for vaccine development. However, despite the high effectiveness of γ-Flu vaccines, the need to incorporate an adjuvant to improve vaccine-mediated protection seems inevitable. Here, we examined the protective efficacy of an intranasal gamma-irradiated HIN1 vaccine co-administered with a plasmid encoding mouse interleukin-28B (mIL-28B) as a novel adjuvant in BALB/c mice. Animals were immunized intranasally three times at one-week intervals with γ-Flu, alone or in combination with the mIL-28B adjuvant, followed by viral challenge with a high lethal dose (10 LD50) of A/PR/8/34 (H1N1) influenza virus. Virus-specific antibody, cellular and mucosal responses, and the balance of cytokines in the spleen IFN-γ, IL-12, and IL-4) and in lung homogenates (IL-6 and IL-10) were measured by ELISA. The lymphoproliferative activity of restimulated spleen cells was also determined by MTT assay. Furthermore, virus production in the lungs of infected mice was estimated using the Madin-Darby canine kidney (MDCK)/hemagglutination assay (HA). Our data showed that intranasal immunization with adjuvanted γ-Flu vaccine efficiently promoted humoral, cellular, and mucosal immune responses and efficiently decreased lung virus titers, all of which are associated with protection against challenge. This combination also reduced IL-6 and IL-10 levels in lung homogenates. The results suggest that IL-28B can enhance the ability of the vaccine to elicit virus-specific immune responses and could potentially be used as an effective adjuvant.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Citocinas/imunologia , Imunidade Celular/imunologia , Imunidade nas Mucosas/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Infecções por Orthomyxoviridae/imunologia , Administração Intranasal/métodos , Animais , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Cães , Feminino , Imunização/métodos , Vacinas contra Influenza/imunologia , Pulmão/imunologia , Pulmão/virologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/virologia , Vacinação/métodos
7.
Arch Virol ; 166(2): 571-579, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33410993

RESUMO

This study compared concurrent and separate primary vaccination against equid alphaherpesviruses 1 and 4, genus Varicellovirus, subfamily Alphaherpesvirinae, family Herpesviridae, and equine influenza A virus, genus Alphainfluenzavirus, family Orthomyxoviridae. Their vernacular names are equine herpesvirus 1 and 4 (EHV1/4) and equine influenza virus (EIV). Infection with these respiratory pathogens is associated with loss of performance, interruption of training schedules, and on occasion, cancellation of equestrian events. Vaccination is highly recommended, and for some activities it is a mandatory requirement of the relevant authority. As there is a dearth of information relating to the impact of concurrent vaccination on the antibody response to EHV and EIV vaccines, they are usually administered separately, often 2 weeks apart. In a previous study of booster vaccination in Thoroughbred racehorses, concurrent vaccination with whole-virus inactivated carbopol-adjuvanted EHV and EIV vaccines did not impact negatively on the antibody response. In this study, investigations were extended to concurrent versus separate primary vaccination of warmblood foals. A field study was conducted to compare the immune response to a carbopol-adjuvanted EHV vaccine and an immune stimulating complex (ISCOM)-adjuvanted EI vaccine administered concurrently and 2 weeks apart. No adverse clinical reactions were observed, the pattern of EI and EHV antibody response was similar for both groups, and there was no evidence that concurrent primary vaccination compromised the humoral response. The results are of relevance to horse owners who wish to decrease veterinary costs, limit handling of young animals, and simplify record keeping by vaccinating concurrently.


Assuntos
Infecções por Herpesviridae/imunologia , Vacinas contra Herpesvirus/imunologia , Doenças dos Cavalos/imunologia , Cavalos/imunologia , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Feminino , Doenças dos Cavalos/virologia , Cavalos/virologia , Imunidade Humoral/imunologia , Imunização Secundária/métodos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Vacinação/métodos , Vacinas de Produtos Inativados/imunologia
8.
Methods Mol Biol ; 2183: 331-356, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32959252

RESUMO

Vaccination was developed by Edward Jenner in 1796. Since then, vaccination and vaccine development research has been a hotspot of research in the scientific community. Various ways of vaccine development are successfully employed in mass production of vaccines. One of the most successful ways to generate vaccines is the method of virulence attenuation in pathogens. The attenuated strains of viruses, bacteria, and parasites are used as vaccines which elicit robust immune response and confers protection against virulent pathogens. This chapter brings together the most common and efficient ways of generating live attenuated vaccine strains in viruses, bacteria, and parasites.


Assuntos
Vacinas Atenuadas/imunologia , Vacinologia/métodos , Animais , Vacinas Bacterianas , Linhagem Celular , Uso do Códon , Feminino , Raios gama , Inativação Gênica , Humanos , Imunização , Imunogenicidade da Vacina , Vírus da Influenza A , Camundongos , MicroRNAs/genética , Modelos Animais , Mutagênese , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Vacinas Protozoárias/genética , Vacinas Protozoárias/imunologia , Radiação Ionizante , Vacinas Atenuadas/genética , Virulência/imunologia
9.
Viruses ; 12(12)2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348840

RESUMO

Delivering rapid protection against infectious agents to non-immune populations is a formidable public health challenge. Although passive immunotherapy is a fast and effective method of protection, large-scale production and administration of monoclonal antibodies (mAbs) is expensive and unpractical. Viral vector-mediated delivery of mAbs offers an attractive alternative to their direct injection. Integrase-defective lentiviral vectors (IDLV) are advantageous for this purpose due to the absence of pre-existing anti-vector immunity and the safety features of non-integration and non-replication. We engineered IDLV to produce the humanized mAb VN04-2 (IDLV-VN04-2), which is broadly neutralizing against H5 influenza A virus (IAV), and tested the vectors' ability to produce antibodies and protect from IAV in vivo. We found that IDLV-transduced cells produced functional VN04-2 mAbs in a time- and dose-dependent fashion. These mAbs specifically bind the hemagglutinin (HA), but not the nucleoprotein (NP) of IAV. VN04-2 mAbs were detected in the serum of mice at different times after intranasal (i.n.) or intramuscular (i.m.) administration of IDLV-VN04-2. Administration of IDLV-VN04-2 by the i.n. route provided rapid protection against lethal IAV challenge, although the protection did not persist at later time points. Our data suggest that administration of mAb-expressing IDLV may represent an effective strategy for rapid protection against infectious diseases.


Assuntos
Anticorpos Monoclonais/genética , Anticorpos Antivirais/genética , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Integrase de HIV/genética , Lentivirus/genética , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Expressão Gênica , Ordem dos Genes , Células HEK293 , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vírus da Influenza A/imunologia , Camundongos , Infecções por Orthomyxoviridae/imunologia
10.
Front Immunol ; 11: 559113, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072098

RESUMO

As the recent outbreak of SARS-CoV-2 has highlighted, the threat of a pandemic event from zoonotic viruses, such as the deadly influenza A/H7N9 virus subtype, continues to be a major global health concern. H7N9 virus strains appear to exhibit greater disease severity in mammalian hosts compared to natural avian hosts, though the exact mechanisms underlying this are somewhat unclear. Knowledge of the H7N9 host-pathogen interactions have mainly been constrained to natural sporadic human infections. To elucidate the cellular immune mechanisms associated with disease severity and progression, we used a ferret model to closely resemble disease outcomes in humans following influenza virus infection. Intriguingly, we observed variable disease outcomes when ferrets were inoculated with the A/Anhui/1/2013 (H7N9) strain. We observed relatively reduced antigen-presenting cell activation in lymphoid tissues which may be correlative with increased disease severity. Additionally, depletions in CD8+ T cells were not apparent in sick animals. This study provides further insight into the ways that lymphocytes maturate and traffic in response to H7N9 infection in the ferret model.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Linfócitos T CD8-Positivos/imunologia , Interações Hospedeiro-Patógeno/imunologia , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Infecções por Orthomyxoviridae/imunologia , Animais , Células Apresentadoras de Antígenos/patologia , Betacoronavirus/imunologia , Linfócitos T CD8-Positivos/patologia , Infecções por Coronavirus/imunologia , Modelos Animais de Doenças , Furões , Humanos , Infecções por Orthomyxoviridae/patologia , Pandemias , Pneumonia Viral/imunologia
11.
PLoS One ; 15(8): e0227157, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817719

RESUMO

In mice, experimental influenza virus infection stimulates CD8 T cell infiltration of the airways. Virus is cleared by day 9, and between days 8 and 9 there is an abrupt change in CD8 T cell motility behavior transitioning from low velocity and high confinement on day 8, to high velocity with continued high confinement on day 9. We hypothesized that loss of virus and/or antigen signals in the context of high chemokine levels drives the T cells into a rapid surveillance mode. Virus infection induces chemokine production, which may change when the virus is cleared. We therefore sought to examine this period of rapid changes to the T cell environment in the tissue and seek evidence on the roles of peptide-MHC and chemokine receptor interactions. Experiments were performed to block G protein coupled receptor (GPCR) signaling with Pertussis toxin (Ptx). Ptx treatment generally reduced cell velocities and mildly increased confinement suggesting chemokine mediated arrest (velocity <2 µm/min) (Friedman RS, 2005), except on day 8 when velocity increased and confinement was relieved. Blocking specific peptide-MHC with monoclonal antibody unexpectedly decreased velocities on days 7 through 9, suggesting TCR/peptide-MHC interactions promote cell mobility in the tissue. Together, these results suggest the T cells are engaged with antigen bearing and chemokine producing cells that affect motility in ways that vary with the day after infection. The increase in velocities on day 9 were reversed by addition of specific peptide, consistent with the idea that antigen signals become limiting on day 9 compared to earlier time points. Thus, antigen and chemokine signals act to alternately promote and restrict CD8 T cell motility until the point of virus clearance, suggesting the switch in motility behavior on day 9 may be due to a combination of limiting antigen in the presence of high chemokine signals as the virus is cleared.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Movimento Celular/fisiologia , Vírus da Influenza A/imunologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/fisiologia , Movimento Celular/efeitos dos fármacos , Quimiocinas/imunologia , Vírus da Influenza A/patogenicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Orthomyxoviridae , Infecções por Orthomyxoviridae/imunologia , Toxina Pertussis/metabolismo , Toxina Pertussis/farmacologia , Receptores de Quimiocinas , Receptores Acoplados a Proteínas-G/metabolismo
12.
PLoS Pathog ; 16(8): e1008760, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32790753

RESUMO

Influenza A viruses (IAVs) remain a significant global health burden. Activation of the innate immune response is important for controlling early virus replication and spread. It is unclear how early IAV replication events contribute to immune detection. Additionally, while many cell types in the lung can be infected, it is not known if all cell types contribute equally to establish the antiviral state in the host. Here, we use single-cycle influenza A viruses (scIAVs) to characterize the early immune response to IAV in vitro and in vivo. We found that the magnitude of virus replication contributes to antiviral gene expression within infected cells prior to the induction of a global response. We also developed a scIAV that is only capable of undergoing primary transcription, the earliest stage of virus replication. Using this tool, we uncovered replication stage-specific responses in vitro and in vivo. Using several innate immune receptor knockout cell lines, we identify RIG-I as the predominant antiviral detector of primary virus transcription and amplified replication in vitro. Through a Cre-inducible reporter mouse, we used scIAVs expressing Cre-recombinase to characterize cell type-specific responses in vivo. Individual cell types upregulate unique sets of antiviral genes in response to both primary virus transcription and amplified replication. We also identified antiviral genes that are only upregulated in response to direct infection. Altogether, these data offer insight into the early mechanisms of antiviral gene activation during influenza A infection.


Assuntos
Células Epiteliais/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/imunologia , Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Infecções por Orthomyxoviridae/imunologia , Replicação Viral , Células A549 , Animais , Antivirais/farmacologia , Proteína DEAD-box 58/metabolismo , Cães , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Células HEK293 , Humanos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Influenza Humana/tratamento farmacológico , Influenza Humana/patologia , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia
13.
PLoS One ; 15(8): e0237218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760143

RESUMO

Influenza is an infectious respiratory illness caused by influenza viruses. Despite yearly updates, the efficacy of influenza vaccines is significantly curtailed by the virus antigenic drift and antigenic shift. These constant changes to the influenza virus make-up also challenge the development of a universal flu vaccine, which requires conserved antigenic regions shared by influenza viruses of different subtypes. We propose that it is possible to bypass these challenges by the development of an influenza vaccine based on conserved proteins delivered in an adjuvanted nanoparticle system. In this study, we generated influenza nanoparticle constructs using trimethyl chitosan nanoparticles (TMC nPs) as the carrier of recombinant influenza hemagglutinin subunit 2 (HA2) and nucleoprotein (NP). The purified HA2 and NP recombinant proteins were encapsulated into TMC nPs to form HA2-TMC nPs and NP-TMC nPs, respectively. Primary human intranasal epithelium cells (HNEpCs) were used as an in vitro model to measure immunity responses. HA2-TMC nPs, NP-TMC nPs, and HA2-NP-TMC nPs (influenza nanoparticle constructs) showed no toxicity in HNEpCs. The loading efficiency of HA2 and NP into the TMC nPs was 97.9% and 98.5%, respectively. HA2-TMC nPs and NP-TMC nPs more efficiently delivered HA2 and NP proteins to HNEpCs than soluble HA2 and NP proteins alone. The induction of various cytokines and chemokines was more evident in influenza nanoparticle construct-treated HNEpCs than in soluble protein-treated HNEpCs. In addition, soluble factors secreted by influenza nanoparticle construct-treated HNEpCs significantly induced MoDCs maturation markers (CD80, CD83, CD86 and HLA-DR), as compared to soluble factors secreted by protein-treated HNEpCs. HNEpCs treated with the influenza nanoparticle constructs significantly reduced influenza virus replication in an in vitro challenge assay. The results indicate that TMC nPs can be used as influenza vaccine adjuvants and carriers capable of delivering HA2 and NP proteins to HNEpCs.


Assuntos
Adjuvantes Imunológicos/farmacologia , Quitosana/farmacologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/farmacologia , Influenza Humana/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Animais , Linhagem Celular , Células Cultivadas , Quitosana/administração & dosagem , Cães , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/administração & dosagem , Glicoproteínas de Hemaglutininação de Vírus da Influenza/farmacologia , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Células Madin Darby de Rim Canino , Nanopartículas/administração & dosagem , Proteínas do Nucleocapsídeo , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Proteínas de Ligação a RNA/administração & dosagem , Proteínas de Ligação a RNA/farmacologia , Proteínas do Core Viral/administração & dosagem , Proteínas do Core Viral/farmacologia
14.
PLoS Pathog ; 16(7): e1008506, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645119

RESUMO

Circulating androgens can modulate immune cell activity, but the impact of androgens on viral pathogenesis remains unclear. Previous data demonstrate that testosterone reduces the severity of influenza A virus (IAV) infection in male mice by mitigating pulmonary inflammation rather than by affecting viral replication. To examine the immune responses mediated by testosterone to mitigate IAV-induced inflammation, adult male mice remained gonadally intact or were gonadectomized and treated with either placebo or androgen-filled (i.e., testosterone or dihydrotestosterone) capsules prior to sublethal IAV infection. Like intact males, treatment of gonadectomized males with androgens improved the outcome of IAV infection, which was not mediated by changes in the control of virus replication or pulmonary cytokine activity. Instead, androgens accelerated pulmonary leukocyte contraction to limit inflammation. To identify which immune cells were contracting in response to androgens, the composition of pulmonary cellular infiltrates was analyzed and revealed that androgens specifically accelerated the contraction of total pulmonary inflammatory monocytes during peak disease, as well as CD8+ T cells, IAV-specific CD8+ T numbers, cytokine production and degranulation by IAV-specific CD8+ T cells, and the influx of eosinophils into the lungs following clearance of IAV. Neither depletion of eosinophils nor adoptive transfer of CD8+ T cells could reverse the ability of testosterone to protect males against IAV suggesting these were secondary immunologic effects. The effects of testosterone on the contraction of immune cell numbers and activity were blocked by co-administration of the androgen receptor antagonist flutamide and mimicked by treatment with dihydrotestosterone, which was also able to reduce the severity of IAV in female mice. These data suggest that androgen receptor signaling creates a local pulmonary environment that promotes downregulation of detrimental inflammatory immune responses to protect against prolonged influenza disease.


Assuntos
Vírus da Influenza A/imunologia , Pulmão/efeitos dos fármacos , Infecções por Orthomyxoviridae/imunologia , Receptores Androgênicos/metabolismo , Testosterona/farmacologia , Animais , Feminino , Inflamação/imunologia , Inflamação/virologia , Pulmão/imunologia , Masculino , Camundongos Endogâmicos C57BL , Ratos , Receptores Androgênicos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
15.
Mol Immunol ; 125: 51-62, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32645550

RESUMO

Suppressor of cytokine signaling 3 (SOCS3) is a negative regulator of TBK1 and interferon pathway and the expression of SOCS3 is closely correlated with symptoms of influenza patients. However, whether deletion of Socs3 in the lung epithelial cells would affect influenza lung replication and inflammation in vivo is unknown. To test this, we approached the influenza infected Socs3f/f and SpcCre.Socs3f/f mice. We first found that knockdown of Socs3 in lung epithelial cells reduced influenza replication. However, in the in vivo study, there was a reduction of SOCS3 in the influenza-infected neutrophils coincided with an increase of SOCS3 in the CD45-CD326+ lung epithelial cells in PR8-infected SpcCre.Socs3f/f mice. SOCS3-deficient neutrophils expressed higher levels of IL-17 that enhanced chemokine expression in the lung epithelial cells. Lung SOCS3-dificient epithelial cells increased expression of GM-CSF and PGE2 which promoted SpcCre.Socs3f/f neutrophils to yield SOCS3. SpcCre.Socs3f/f lung epithelial cells internalized SOCS3 released from GM-CSF + PGE2-stimulated SpcCre.Socs3f/f neutrophils, which could boost influenza replication in the lung epithelial cells. Thus, in the in vivo study, deletion of SOCS3 from lung epithelium could be nullified by the uptake from SOCS3 from infiltrated neutrophils. In addition, deletion of Socs3 from myeloid cells reduced lung influenza infection, but increased lung inflammation. Taken together, deletion of SOCS3 could suppress influenza replication, but intracellular SOCS3 communication between neutrophils and lung epithelial cells confounds this effect.


Assuntos
Células Epiteliais Alveolares/imunologia , Neutrófilos/imunologia , Infecções por Orthomyxoviridae/imunologia , Infecções Respiratórias/imunologia , Proteína 3 Supressora da Sinalização de Citocinas/imunologia , Células Epiteliais Alveolares/metabolismo , Animais , Vírus da Influenza A , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Infecções Respiratórias/metabolismo , Infecções Respiratórias/virologia , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo
16.
J Virol ; 94(18)2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32611750

RESUMO

Since its detection in swine, influenza D virus (IDV) has been shown to be present in multiple animal hosts, and bovines have been identified as its natural reservoir. However, it remains unclear how IDVs emerge, evolve, spread, and maintain in bovine populations. Through multiple years of virological and serological surveillance in a single order-buyer cattle facility in Mississippi, we showed consistently high seroprevalence of IDVs in cattle and recovered a total of 32 IDV isolates from both healthy and sick animals, including those with antibodies against IDV. Genomic analyses of these isolates along with those isolated from other areas showed that active genetic reassortment occurred in IDV and that five reassortants were identified in the Mississippian facility. Two antigenic groups were identified through antigenic cartography analyses for these 32 isolates and representative IDVs from other areas. Remarkably, existing antibodies could not protect cattle from experimental reinfection with IDV. Additional phenotypic analyses demonstrated variations in growth dynamics and pathogenesis in mice between viruses independent of genomic constellation. In summary, this study suggests that, in addition to epidemiological factors, the ineffectiveness of preexisting immunity and cocirculation of a diverse viral genetic pool could facilitate its high prevalence in animal populations.IMPORTANCE Influenza D viruses (IDVs) are panzootic in multiple animal hosts, but the underlying mechanism is unclear. Through multiple years of surveillance in the same order-buyer cattle facility, 32 IDV isolates were recovered from both healthy and sick animals, including those with evident antibodies against IDV. Active reassortment occurred in the cattle within this facility and in those across other areas, and multiple reassortants cocirculated in animals. These isolates are shown with a large extent of phenotypic diversity in replication efficiency and pathogenesis but little in antigenic properties. Animal experiments demonstrated that existing antibodies could not protect cattle from experimental reinfection with IDV. This study suggests that, in addition to epidemiological factors, limited protection from preexisting immunity against IDVs in cattle herds and cocirculation of a diverse viral genetic pool likely facilitate the high prevalence of IDVs in animal populations.


Assuntos
Anticorpos Antivirais/sangue , Proteção Cruzada , Genoma Viral , Infecções por Orthomyxoviridae/epidemiologia , Vírus Reordenados/imunologia , Thogotovirus/imunologia , Animais , Bovinos , Monitoramento Epidemiológico , Fazendas , Variação Genética , Genótipo , Hospitais Veterinários , Imunidade Inata , Camundongos , Mississippi/epidemiologia , Tipagem Molecular , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Vírus Reordenados/patogenicidade , Estudos Soroepidemiológicos , Thogotovirus/classificação , Thogotovirus/genética , Thogotovirus/patogenicidade , Replicação Viral
17.
J Virol ; 94(17)2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32611751

RESUMO

Low-pathogenicity avian influenza A(H9N2) viruses, enzootic in poultry populations in Asia, are associated with fewer confirmed human infections but higher rates of seropositivity compared to A(H5) or A(H7) subtype viruses. Cocirculation of A(H5) and A(H7) viruses leads to the generation of reassortant viruses bearing A(H9N2) internal genes with markers of mammalian adaptation, warranting continued surveillance in both avian and human populations. Here, we describe active surveillance efforts in live poultry markets in Vietnam in 2018 and compare representative viruses to G1 and Y280 lineage viruses that have infected humans. Receptor binding properties, pH thresholds for HA activation, in vitro replication in human respiratory tract cells, and in vivo mammalian pathogenicity and transmissibility were investigated. While A(H9N2) viruses from both poultry and humans exhibited features associated with mammalian adaptation, one human isolate from 2018, A/Anhui-Lujiang/39/2018, exhibited increased capacity for replication and transmission, demonstrating the pandemic potential of A(H9N2) viruses.IMPORTANCE A(H9N2) influenza viruses are widespread in poultry in many parts of the world and for over 20 years have sporadically jumped species barriers to cause human infection. As these viruses continue to diversify genetically and antigenically, it is critical to closely monitor viruses responsible for human infections, to ascertain if A(H9N2) viruses are acquiring properties that make them better suited to infect and spread among humans. In this study, we describe an active poultry surveillance system established in Vietnam to identify the scope of influenza viruses present in live bird markets and the threat they pose to human health. Assessment of a recent A(H9N2) virus isolated from an individual in China in 2018 is also reported, and it was found to exhibit properties of adaptation to humans and, importantly, it shows similarities to strains isolated from the live bird markets of Vietnam.


Assuntos
Evolução Molecular , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/imunologia , Influenza Aviária/virologia , Influenza Humana/virologia , Fenótipo , Replicação Viral/genética , Animais , Ásia , China , Modelos Animais de Doenças , Feminino , Variação Genética , Humanos , Influenza Aviária/imunologia , Influenza Aviária/transmissão , Influenza Humana/imunologia , Influenza Humana/transmissão , Masculino , Mamíferos , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Aves Domésticas/virologia , Doenças das Aves Domésticas/virologia , Vietnã
18.
Mol Immunol ; 125: 178-186, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717666

RESUMO

PM2.5, a major component of air pollutants, has caused severe health problems. It has been reported that PM2.5 index is closely associated with severity of influenza A virus (IAV) infection. However, the underlying mechanisms have not been addressed. NLRP3 inflammasome and type I interferon signaling regulate host defense against influenza infection. The present study investigated the potential effects of air pollutants on host defense against influenza infection in vitro and in vivo. In this study, different concentrations of PM2.5 were pre-exposed to macrophages and mice before IAV infection to assess the negative effects of air pollutants in virus infection. We found that exposure to PM2.5 deteriorated influenza virus infection via compromising innate immune responses manifested by a decrease IL-1ß and IFN-ß production in vitro. Meanwhile, mice exposed with PM2.5 were susceptible to PR8 virus infection due to down-regulation of IL-1ß and IFN-ß. Mechanistically, PM 2.5 exposure suppressed the NLRP3 inflammasome activation and the AHR-TIPARP signaling pathway, by which compromised the anti-influenza immunity. Thus, our study revealed that PM2.5 could alter macrophage inflammatory responses by suppressing LPS-induced activation of NLRP3 inflammasome and expression of IFN-ß during influenza infection. These findings provided us new insights in understanding that PM2.5 combining with influenza infection could enhance the severity of pneumonia.


Assuntos
Poluentes Atmosféricos/toxicidade , Inflamassomos/efeitos dos fármacos , Interferon beta/biossíntese , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Infecções por Orthomyxoviridae/imunologia , Material Particulado/toxicidade , Animais , Inflamassomos/imunologia , Inflamassomos/metabolismo , Vírus da Influenza A Subtipo H1N1 , Interferon beta/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Infecções por Orthomyxoviridae/metabolismo
19.
PLoS One ; 15(7): e0235706, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32639988

RESUMO

During type 1 immune responses, CD4 T helper 1 (Th1) cells and CD8 T cells are activated via IL-12 and contribute to the elimination of intracellular pathogens through interferon gamma (IFNγ) production. In this study, we identified Placenta-specific 8 (Plac8) as a gene that is uniquely expressed in Th1 CD4 T cells relative to other CD4 T cell subsets and hypothesized that Plac8 may represent a novel therapeutic target in Th1 CD4 T cells. First, we determined that Plac8 mRNA in CD4 T cells was induced following IL-12 stimulation via an indirect route that required new protein synthesis. Upon evaluating the functional relevance of Plac8 expression in Th1 CD4 T cells, we discovered that Plac8 was important for suppressing IFNγ mRNA and protein production by CD4 T cells 24 hours after IL-12 stimulation, however Plac8 did not contribute to pathogenic CD4 T cell function during two models of intestinal inflammation. We also noted relatively high basal expression of Plac8 in CD8 T cells which could be further induced following IL-12 stimulation in CD8 T cells. Furthermore, Plac8 expression was important for establishing an optimal CD8 T cell response against influenza A virus via a T cell-intrinsic manner. Altogether, these results implicate Plac8 as a potential regulator of Th1 CD4 and CD8 T cell responses during Th1 T cell-driven inflammation.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Interferon gama/metabolismo , Proteínas/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Colite/imunologia , Colite/patologia , Modelos Animais de Doenças , Interferon gama/genética , Interleucina-12/farmacologia , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Proteínas/genética , RNA Mensageiro/metabolismo , Regulação para Cima/efeitos dos fármacos
20.
Proc Natl Acad Sci U S A ; 117(29): 17221-17227, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32631992

RESUMO

Immunity to influenza viruses can be long-lived, but reinfections with antigenically distinct viral strains and subtypes are common. Reinfections can boost antibody responses against viral strains first encountered in childhood through a process termed "original antigenic sin." It is unknown how initial childhood exposures affect the induction of antibodies against the hemagglutinin (HA) stalk domain of influenza viruses. This is an important consideration since broadly reactive HA stalk antibodies can protect against infection, and universal vaccine platforms are being developed to induce these antibodies. Here we show that experimentally infected ferrets and naturally infected humans establish strong "immunological imprints" against HA stalk antigens first encountered during primary influenza virus infections. We found that HA stalk antibodies are surprisingly boosted upon subsequent infections with antigenically distinct influenza A virus subtypes. Paradoxically, these heterosubtypic-boosted HA stalk antibodies do not bind efficiently to the boosting influenza virus strain. Our results demonstrate that an individual's HA stalk antibody response is dependent on the specific subtype of influenza virus that they first encounter early in life. We propose that humans are susceptible to heterosubtypic influenza virus infections later in life since these viruses boost HA stalk antibodies that do not bind efficiently to the boosting antigen.


Assuntos
Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Infecções por Orthomyxoviridae/imunologia , Animais , Furões , Hemaglutininas , Humanos , Imunização Secundária , Imunoglobulina G/sangue , Proteínas Recombinantes
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