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1.
Vaccine ; 38(42): 6487-6499, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32907757

RESUMO

The many carbohydrate chains on Covid-19 coronavirus SARS-CoV-2 and its S-protein form a glycan-shield that masks antigenic peptides and decreases uptake of inactivated virus or S-protein vaccines by APC. Studies on inactivated influenza virus and recombinant gp120 of HIV vaccines indicate that glycoengineering of glycan-shields to present α-gal epitopes (Galα1-3Galß1-4GlcNAc-R) enables harnessing of the natural anti-Gal antibody for amplifying vaccine efficacy, as evaluated in mice producing anti-Gal. The α-gal epitope is the ligand for the natural anti-Gal antibody which constitutes ~1% of immunoglobulins in humans. Upon administration of vaccines presenting α-gal epitopes, anti-Gal binds to these epitopes at the vaccination site and forms immune complexes with the vaccines. These immune complexes are targeted for extensive uptake by APC as a result of binding of the Fc portion of immunocomplexed anti-Gal to Fc receptors on APC. This anti-Gal mediated effective uptake of vaccines by APC results in 10-200-fold higher anti-viral immune response and in 8-fold higher survival rate following challenge with a lethal dose of live influenza virus, than same vaccines lacking α-gal epitopes. It is suggested that glycoengineering of carbohydrate chains on the glycan-shield of inactivated SARS-CoV-2 or on S-protein vaccines, for presenting α-gal epitopes, will have similar amplifying effects on vaccine efficacy. α-Gal epitope synthesis on coronavirus vaccines can be achieved with recombinant α1,3galactosyltransferase, replication of the virus in cells with high α1,3galactosyltransferase activity as a result of stable transfection of cells with several copies of the α1,3galactosyltransferase gene (GGTA1), or by transduction of host cells with replication defective adenovirus containing this gene. In addition, recombinant S-protein presenting multiple α-gal epitopes on the glycan-shield may be produced in glycoengineered yeast or bacteria expression systems containing the corresponding glycosyltransferases. Prospective Covid-19 vaccines presenting α-gal epitopes may provide better protection than vaccines lacking this epitope because of increased uptake by APC.


Assuntos
Antígenos Virais/genética , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/genética , Trissacarídeos/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/biossíntese , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/virologia , Engenharia Genética , Proteína do Núcleo p24 do HIV/química , Proteína do Núcleo p24 do HIV/genética , Proteína do Núcleo p24 do HIV/imunologia , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/imunologia , Humanos , Imunogenicidade da Vacina , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/virologia , Camundongos , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Trissacarídeos/química , Vacinas Virais/administração & dosagem , Vacinas Virais/biossíntese , Vacinas Virais/genética
2.
Cells ; 9(9)2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911691

RESUMO

The ongoing pandemic due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has so far infected about 2.42 × 107 (as at 27 August 2020) subjects with more than 820,000 deaths. It is the third zoonotic coronavirus-dependent outbreak in the last twenty years and represents a major infective threat for public health worldwide. A main aspect of the infection, in analogy to other viral infections, is the so-called "cytokine storm", an inappropriate molecular response to virus spread which plays major roles in tissue and organ damage. Immunological therapies, including vaccines and humanized monoclonal antibodies, have been proposed as major strategies for prevention and treatment of the disease. Accordingly, a detailed mechanistic knowledge of the molecular events with which the virus infects cells and induces an immunological response appears necessary. In this review, we will report details of the initial process of SARS-CoV-2 cellular entry with major emphasis on the maturation of the spike protein. Then, a particular focus will be devoted to describe the possible mechanisms by which dendritic cells, a major cellular component of innate and adaptive immune responses, may play a role in the spread of the virus in the human body and in the clinical evolution of the disease.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Células Dendríticas/virologia , Pneumonia Viral/virologia , Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/metabolismo , Piroptose , Sistema Renina-Angiotensina , Internalização do Vírus
3.
PLoS Pathog ; 16(7): e1008601, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32614902

RESUMO

Sexual transmission and persistence of Zika virus (ZIKV) in the testes pose new challenges for controlling virus outbreaks and developing live-attenuated vaccines. It has been shown that testicular infection of ZIKV is initiated in the testicular interstitium, followed by spread of the virus in the seminiferous tubules. This leads to testicular damage and/or viral dissemination into the epididymis and eventually into semen. However, it remains unknown which cell types are targeted by ZIKV in the testicular interstitium, and what is the specific order of infectious events leading to ZIKV invasion of the seminiferous tubules. Here, we demonstrate that interstitial leukocytes expressing mir-511-3p microRNA are the initial targets of ZIKV in the testes, and infection of mir-511-3p-expressing cells in the testicular interstitium is necessary for downstream infection of the seminiferous tubules. Mir-511-3p is expressed concurrently with CD206, a marker of lineage 2 (M2) macrophages and monocyte derived dendritic cells (moDCs). Selective restriction of ZIKV infection of CD206-expressing M2 macrophages/moDCs results in the attenuation of macrophage-associated inflammatory responses in vivo and prevents the disruption of the Sertoli cell barrier in vitro. Finally, we show that targeting of viral genome for mir-511-3p significantly attenuates early ZIKV replication not only in the testes, but also in many peripheral organs, including spleen, epididymis, and pancreas. This incriminates M2 macrophages/moDCs as important targets for visceral ZIKV replication following hematogenous dissemination of the virus from the site of infection.


Assuntos
Células Dendríticas/virologia , Macrófagos/virologia , Testículo/virologia , Tropismo Viral/fisiologia , Infecção por Zika virus/virologia , Zika virus/fisiologia , Animais , Masculino , Camundongos
4.
J Transl Med ; 18(1): 261, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600410

RESUMO

Amino-bisphosphonates such as zoledronic acid (ZA) can possibly ameliorate or prevent severe COVID-19 disease by at least three distinct mechanisms: (1) as immunostimulants which could boost γδ T cell expansion, important in the acute response in the lung; (2) as DC modulators, limiting their ability to only partially activate T cells; and (3) as prenylation inhibitors of small GTPases in the endosomal pathway of the DC to prevent expulsion of lysosomes containing SARS-CoV-2 virions. Use of ZA or other amino-bisphosphonates as modulators of COVID-19 disease should be considered.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Células Dendríticas/virologia , Difosfonatos/uso terapêutico , Endossomos/metabolismo , Fatores Imunológicos/farmacologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Animais , Células Dendríticas/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Humanos , Pandemias
5.
J Infect Dis ; 222(5): 734-745, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32563187

RESUMO

Clinical manifestations of coronavirus disease 2019 (COVID-19) vary from asymptomatic virus shedding, nonspecific pharyngitis, to pneumonia with silent hypoxia and respiratory failure. Dendritic cells and macrophages are sentinel cells for innate and adaptive immunity that affect the pathogenesis of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). The interplay between SARS-CoV-2 and these cell types remains unknown. We investigated infection and host responses of monocyte-derived dendritic cells (moDCs) and macrophages (MDMs) infected by SARS-CoV-2. MoDCs and MDMs were permissive to SARS-CoV-2 infection and protein expression but did not support productive virus replication. Importantly, SARS-CoV-2 launched an attenuated interferon response in both cell types and triggered significant proinflammatory cytokine/chemokine expression in MDMs but not moDCs. Investigations suggested that this attenuated immune response to SARS-CoV-2 in moDCs was associated with viral antagonism of STAT1 phosphorylation. These findings may explain the mild and insidious course of COVID-19 until late deterioration.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Células Dendríticas/imunologia , Interferons/imunologia , Monócitos/imunologia , Pneumonia Viral/imunologia , Fator de Transcrição STAT1/antagonistas & inibidores , Imunidade Adaptativa , Animais , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Betacoronavirus/metabolismo , Quimiocinas/metabolismo , Chlorocebus aethiops , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Citocinas/metabolismo , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Humanos , Macrófagos/imunologia , Macrófagos/virologia , Monócitos/virologia , Pandemias , Fosforilação , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT1/metabolismo , Células Vero , Replicação Viral/fisiologia , Eliminação de Partículas Virais
6.
Front Immunol ; 11: 1312, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582222

RESUMO

Respiratory, circulatory, and renal failure are among the gravest features of COVID-19 and are associated with a very high mortality rate. A common denominator of all affected organs is the expression of angiotensin-converting enzyme 2 (ACE2), a protease responsible for the conversion of Angiotensin 1-8 (Ang II) to Angiotensin 1-7 (Ang 1-7). Ang 1-7 acts on these tissues and in other target organs via Mas receptor (MasR), where it exerts beneficial effects, including vasodilation and suppression of inflammation and fibrosis, along an attenuation of cardiac and vascular remodeling. Unfortunately, ACE2 also serves as the binding receptor of SARS viral spike glycoprotein, enabling its attachment to host cells, with subsequent viral internalization and replication. Although numerous reports have linked the devastating organ injuries to viral homing and attachment to organ-specific cells widely expressing ACE2, little attention has been given to ACE-2 expressed by the immune system. Herein we outline potential adverse effects of SARS-CoV2 on macrophages and dendritic cells, key cells of the immune system expressing ACE2. Specifically, we propose a new hypothesis that, while macrophages play an important role in antiviral defense mechanisms, in the case of SARS-CoV, they may also serve as a Trojan horse, enabling viral anchoring specifically within the pulmonary parenchyma. It is tempting to assume that diverse expression of ACE2 in macrophages among individuals might govern the severity of SARS-CoV-2 infection. Moreover, reallocation of viral-containing macrophages migrating out of the lung to other tissues is theoretically plausible in the context of viral spread with the involvement of other organs.


Assuntos
Betacoronavirus/metabolismo , Células Dendríticas/metabolismo , Pulmão/patologia , Macrófagos Alveolares/metabolismo , Peptidil Dipeptidase A/metabolismo , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Humanos , Pulmão/virologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/virologia , Pandemias , Tecido Parenquimatoso/patologia , Tecido Parenquimatoso/virologia , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo
7.
Mol Immunol ; 123: 26-31, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388275

RESUMO

Nanoparticles are highly immunogenic due to the multivalent, repetitive antigen expression and direct activation of antigen presenting cells (APCs), key players of adaptive immune responses. Different virus-like particles (VLPs) have been used as display platforms to amplify immune responses to biologically relevant, but poorly immunogenic foreign antigens. A candidate platform based on rotavirus (RV) inner-capsid protein VP6 oligomers, such as nanotubes (T-VP6) and nanospheres (S-VP6), is also considered. Different VP6 nanostructures were compared for internalization and antigen presentation by the APCs. We found, that a lack of a high-order structures, T-VP6 and S-VP6, did not negatively affect VP6 uptake and presentation by murine bone-marrow derived dendritic cells (BMDCs) in vitro. Furthermore, T-VP6 was preferable to norovirus (NoV) VLPs for BMDC internalization resulting in significantly higher VP6-specific immune responses when T-VP6 and NoV VLP pulsed BMDCs were transferred to syngeneic mice. These results support the use of different VP6 nanostructures as foreign antigen delivery platforms.


Assuntos
Apresentação do Antígeno , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Rotavirus/fisiologia , Animais , Formação de Anticorpos , Antígenos Virais/química , Proteínas do Capsídeo/química , Células Cultivadas , Células Dendríticas/virologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Nanoestruturas/química , Estrutura Terciária de Proteína/fisiologia , Transporte Proteico , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Rotavirus/metabolismo , Internalização do Vírus
8.
Nat Commun ; 11(1): 2421, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415086

RESUMO

Zika virus (ZIKV) is a mosquito-borne pathogen with increasing public health significance. To characterize immune responses to ZIKV, here we examine transcriptional signatures of CD4 T, CD8 T, B, and NK cells, monocytes, myeloid dendritic cells (mDCs), and plasmacytoid dendritic cells (pDCs) from three individuals with ZIKV infection. While gene expression patterns from most cell subsets display signs of impaired antiviral immune activity, pDCs from infected host have distinct transcriptional response associated with activation of innate immune recognition and type I interferon signaling pathways, but downregulation of key host factors known to support ZIKV replication steps; meanwhile, pDCs exhibit a unique expression pattern of gene modules that are correlated with alternative cell populations, suggesting collaborative interactions between pDCs and other immune cells, particularly B cells. Together, these results point towards a discrete but integrative function of pDCs in the human immune responses to ZIKV infection.


Assuntos
Células Dendríticas/imunologia , Infecção por Zika virus/imunologia , Adulto , Animais , Linfócitos B/virologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/virologia , Células Cultivadas , Culicidae , Células Dendríticas/virologia , Feminino , Perfilação da Expressão Gênica , Humanos , Imunidade Inata , Células Matadoras Naturais/virologia , Leucócitos Mononucleares/virologia , Monócitos/metabolismo , Monócitos/virologia , Células Mieloides/virologia , Transcrição Genética , Replicação Viral , Zika virus/imunologia , Infecção por Zika virus/virologia
10.
J Cell Mol Med ; 24(12): 6988-6999, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374474

RESUMO

Outbreaks of infections with viruses like Sars-CoV-2, Ebola virus and Zika virus lead to major global health and economic problems because of limited treatment options. Therefore, new antiviral drug candidates are urgently needed. The promising new antiviral drug candidate silvestrol effectively inhibited replication of Corona-, Ebola-, Zika-, Picorna-, Hepatis E and Chikungunya viruses. Besides a direct impact on pathogens, modulation of the host immune system provides an additional facet to antiviral drug development because suitable immune modulation can boost innate defence mechanisms against the pathogens. In the present study, silvestrol down-regulated several pro- and anti-inflammatory cytokines (IL-6, IL-8, IL-10, CCL2, CCL18) and increased TNF-α during differentiation and activation of M1-macrophages, suggesting that the effects of silvestrol might cancel each other out. However, silvestrol amplified the anti-inflammatory potential of M2-macrophages by increasing expression of anti-inflammatory surface markers CD206, TREM2 and reducing release of pro-inflammatory IL-8 and CCL2. The differentiation of dendritic cells in the presence of silvestrol is characterized by down-regulation of several surface markers and cytokines indicating that differentiation is impaired by silvestrol. In conclusion, silvestrol influences the inflammatory status of immune cells depending on the cell type and activation status.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Citocinas/genética , Células Dendríticas/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Macrófagos/efeitos dos fármacos , Triterpenos/farmacologia , Betacoronavirus/crescimento & desenvolvimento , Betacoronavirus/imunologia , Diferenciação Celular/efeitos dos fármacos , Vírus Chikungunya/efeitos dos fármacos , Vírus Chikungunya/crescimento & desenvolvimento , Vírus Chikungunya/imunologia , Citocinas/classificação , Citocinas/imunologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Ebolavirus/efeitos dos fármacos , Ebolavirus/crescimento & desenvolvimento , Ebolavirus/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Vírus da Hepatite E/efeitos dos fármacos , Vírus da Hepatite E/crescimento & desenvolvimento , Vírus da Hepatite E/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/virologia , Especificidade de Órgãos , Picornaviridae/efeitos dos fármacos , Picornaviridae/crescimento & desenvolvimento , Picornaviridae/imunologia , Cultura Primária de Células , Transdução de Sinais , Zika virus/efeitos dos fármacos , Zika virus/crescimento & desenvolvimento , Zika virus/imunologia
11.
EBioMedicine ; 55: 102768, 2020 May.
Artigo em Inglês | MEDLINE | ID: covidwho-146031

RESUMO

The pandemic spread of a novel coronavirus - SARS coronavirus-2 (SARS-CoV-2) as a cause of acute respiratory illness, named Covid-19, is placing the healthcare systems of many countries under unprecedented stress. Global economies are also spiraling towards a recession in fear of this new life-threatening disease. Vaccines that prevent SARS-CoV-2 infection and therapeutics that reduces the risk of severe Covid-19 are thus urgently needed. A rapid method to derive antiviral treatment for Covid-19 is the use of convalescent plasma derived hyperimmune globulin. However, both hyperimmune globulin and vaccine development face a common hurdle - the risk of antibody-mediated disease enhancement. The goal of this review is to examine the body of evidence supporting the hypothesis of immune enhancement that could be pertinent to Covid-19. We also discuss how this risk could be mitigated so that both hyperimmune globulin and vaccines could be rapidly translated to overcome the current global health crisis.


Assuntos
Anticorpos Antivirais/efeitos adversos , Infecções por Coronavirus/imunologia , Pandemias , Pneumonia Viral/imunologia , Vacinas Virais/imunologia , Internalização do Vírus , Animais , Anticorpos Antivirais/imunologia , Ensaios Clínicos Fase I como Assunto , Convalescença , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Células Dendríticas/virologia , Saúde Global , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Imunização Passiva , Macrófagos/virologia , Modelos Animais , Monócitos/virologia , Pandemias/prevenção & controle , Plasma , Plasmaferese , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Receptores Fc/imunologia , Pesquisa Médica Translacional
12.
PLoS One ; 15(4): e0231049, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32287277

RESUMO

Zika virus (ZIKV) is an emerging mosquito-borne flavivirus that has attracted global attention and international awareness. ZIKV infection exhibits mild symptoms including fever and pains; however, ZIKV has recently been shown to be related to increased birth defects, including microcephaly, in infants. In addition, ZIKV is related to the onset of neurological disorders, such as a type of paralysis similar to Guillain-Barré syndrome. However, the mechanisms through which ZIKV affect neuronal cells and myeloid dendritic cells and how ZIKV avoids host immunity are unclear. Accordingly, in this study, we analyzed RNA sequencing data from ZIKV-infected neuronal cells and myeloid dendritic cells by comparative network analyses using protein-protein interaction information. Comparative network analysis revealed major genes showing differential changes in the peripheral neurons, neural crest cells, and myeloid dendritic cells after ZIKV infection. The genes were related to DNA repair systems and prolactin signaling as well as the interferon signaling, neuroinflammation, and cell cycle pathways. These pathways were interconnected by the interaction of proteins in the pathway and significantly regulated by ZIKV infection in neuronal cells and myeloid dendritic cells. Our analysis showed that neuronal cell damage occurred through up-regulation of neuroinflammation and down-regulation of the DNA repair system, but not in myeloid dendritic cells. Interestingly, immune escape by ZIKV infection could be caused by downregulation of prolactin signaling including IRS2, PIK3C3, JAK3, STAT3, and IRF1 as well as mitochondria dysfunction and oxidative phosphorylation in myeloid dendritic cells. These findings provide insight into the mechanisms of ZIKV infection in the host and the association of ZIKV with neurological and immunological symptoms, which may facilitate the development of therapeutic agents and vaccines.


Assuntos
Células Dendríticas/virologia , Regulação Viral da Expressão Gênica , Células Mieloides/virologia , Neurônios/virologia , Infecção por Zika virus/metabolismo , Zika virus , Células Dendríticas/metabolismo , Humanos , Células Mieloides/metabolismo , Neurônios/metabolismo , Transcrição Genética
13.
EBioMedicine ; 55: 102768, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32344202

RESUMO

The pandemic spread of a novel coronavirus - SARS coronavirus-2 (SARS-CoV-2) as a cause of acute respiratory illness, named Covid-19, is placing the healthcare systems of many countries under unprecedented stress. Global economies are also spiraling towards a recession in fear of this new life-threatening disease. Vaccines that prevent SARS-CoV-2 infection and therapeutics that reduces the risk of severe Covid-19 are thus urgently needed. A rapid method to derive antiviral treatment for Covid-19 is the use of convalescent plasma derived hyperimmune globulin. However, both hyperimmune globulin and vaccine development face a common hurdle - the risk of antibody-mediated disease enhancement. The goal of this review is to examine the body of evidence supporting the hypothesis of immune enhancement that could be pertinent to Covid-19. We also discuss how this risk could be mitigated so that both hyperimmune globulin and vaccines could be rapidly translated to overcome the current global health crisis.


Assuntos
Anticorpos Antivirais/efeitos adversos , Infecções por Coronavirus/imunologia , Pandemias , Pneumonia Viral/imunologia , Vacinas Virais/imunologia , Internalização do Vírus , Animais , Anticorpos Antivirais/imunologia , Ensaios Clínicos Fase I como Assunto , Convalescença , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Células Dendríticas/virologia , Saúde Global , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Imunização Passiva , Macrófagos/virologia , Modelos Animais , Monócitos/virologia , Pandemias/prevenção & controle , Plasma , Plasmaferese , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Receptores Fc/imunologia , Pesquisa Médica Translacional
14.
PLoS Pathog ; 16(3): e1008387, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32126128

RESUMO

Mediator of IRF3 activation (MITA, also named as STING/ERIS/MPYS/TMEM173), is essential to DNA virus- or cytosolic DNA-triggered innate immune responses. In this study, we demonstrated the negative regulatory role of RING-finger protein (RNF) 90 in innate immune responses targeting MITA. RNF90 promoted K48-linked ubiquitination of MITA and its proteasome-dependent degradation. Overexpression of RNF90 inhibited HSV-1- or cytosolic DNA-induced immune responses whereas RNF90 knockdown had the opposite effects. Moreover, RNF90-deficient bone marrow-derived dendritic cells (BMDCs), bone marrow-derived macrophages (BMMs) and mouse embryonic fibroblasts (MEFs) exhibited increased DNA virus- or cytosolic DNA-triggered signaling and RNF90 deficiency protected mice from DNA virus infection. Taken together, our findings suggested a novel function of RNF90 in innate immunity.


Assuntos
Herpesvirus Humano 1/imunologia , Imunidade Inata , Proteínas de Membrana/imunologia , Proteólise , Proteínas com Motivo Tripartido/imunologia , Ubiquitina-Proteína Ligases/imunologia , Ubiquitinação/imunologia , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/virologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Fibroblastos/imunologia , Fibroblastos/virologia , Herpesvirus Humano 1/genética , Macrófagos/imunologia , Macrófagos/virologia , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética
15.
PLoS One ; 15(3): e0229660, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191728

RESUMO

Respiratory syncytial virus (RSV) is the single most important cause of serious lower respiratory tract disease in infants and young children worldwide and a high priority for vaccine development. Despite over 50 years of research, however, no vaccine is yet available. One block to vaccine development is an incomplete understanding of the aberrant memory response to the formalin-inactivated RSV vaccine (FI-RSV) given to children in the 1960s. This vaccine caused enhanced respiratory disease (ERD) with later natural RSV infection. Concern that any non-live virus vaccine may also cause ERD has blocked development of subunit vaccines for young children. A number of animal FI-RSV studies suggest various immune mechanisms behind ERD. However, other than limited data from the original FI-RSV trial, there is no information on the human ERD-associated responses. An in vitro model with human blood specimens may shed light on the immune memory responses likely responsible for ERD. Memory T cell responses to an antigen are guided by the innate responses, particularly dendritic cells that present an antigen in conjunction with co-stimulatory molecules and cytokine signaling. Our in vitro model involves human monocyte derived dendritic cells (moDC) and allogenic T cell cultures to assess innate responses that direct T cell responses. Using this model, we evaluated human responses to live RSV, FI-RSV, and subunit RSV G vaccines (G-containing virus-like particles, G-VLP). Similar to findings in animal studies, FI-RSV induced prominent Th2/Th17-biased responses with deficient type-1 responses compared to live virus. Responses to G-VLPs were similar to live virus, i.e. biased towards a Th1 and not a Th2/Th17. Also mutating CX3C motif in G gave a more pronounced moDC responses associated with type-1 T cell responses. This in vitro model identifies human immune responses likely associated with ERD and provides another pre-clinical tool to assess the safety of RSV vaccines.


Assuntos
Vacinas contra Vírus Sincicial Respiratório/efeitos adversos , Vacinas contra Vírus Sincicial Respiratório/imunologia , Animais , Apresentação do Antígeno , Antígenos Virais/imunologia , Pré-Escolar , Células Dendríticas/imunologia , Células Dendríticas/virologia , Humanos , Imunidade Inata , Memória Imunológica , Técnicas In Vitro , Lactente , Modelos Imunológicos , Infecções por Vírus Respiratório Sincicial/etiologia , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sincicial Respiratório Humano/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/virologia , Vacinas de Subunidades/efeitos adversos , Vacinas de Subunidades/imunologia
16.
PLoS Pathog ; 16(2): e1008151, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32109259

RESUMO

HIV latency is the major barrier to a cure for people living with HIV (PLWH) on antiretroviral therapy (ART) because the virus persists in long-lived non-proliferating and proliferating latently infected CD4+ T cells. Latently infected CD4+ T cells do not express viral proteins and are therefore not visible to immune mediated clearance. Therefore, identifying interventions that can reverse latency and also enhance immune mediated clearance is of high interest. Interferons (IFNs) have multiple immune enhancing effects and can inhibit HIV replication in activated CD4+ T cells. However, the effects of IFNs on the establishment and reversal of HIV latency is not understood. Using an in vitro model of latency, we demonstrated that plasmacytoid dendritic cells (pDC) inhibit the establishment of HIV latency through secretion of type I IFNα, IFNß and IFNω but not IFNε or type III IFNλ1 and IFNλ3. However, once latency was established, IFNα but no other IFNs were able to efficiently reverse latency in both an in vitro model of latency and CD4+ T cells collected from PLWH on suppressive ART. Binding of IFNα to its receptor expressed on primary CD4+ T cells did not induce activation of the canonical or non-canonical NFκB pathway but did induce phosphorylation of STAT1, 3 and 5 proteins. STAT5 has been previously demonstrated to bind to the HIV long terminal repeat and activate HIV transcription. We demonstrate diverse effects of interferons on HIV latency with type I IFNα; inhibiting the establishment of latency but also reversing HIV latency once latency is established.


Assuntos
Linfócitos T CD4-Positivos , Repetição Terminal Longa de HIV/imunologia , HIV-1/fisiologia , Interferon-alfa/imunologia , Transcrição Genética/imunologia , Latência Viral/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Células Dendríticas/virologia , Células HEK293 , Humanos , NF-kappa B/imunologia , Fatores de Transcrição STAT/imunologia
17.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32075937

RESUMO

Dendritic cells (DCs) are one of the earliest targets of HIV-1 infection acting as a "Trojan horse," concealing the virus from the innate immune system and delivering it to T cells via virological synapses (VS). To explicate how the virus is trafficked through the cell to the VS and evades degradation, a high-throughput small interfering RNA screen targeting membrane trafficking proteins was performed in monocyte-derived DCs. We identified several proteins including BIN-1 and RAB7L1 that share common roles in transport from endosomal compartments. Depletion of target proteins resulted in an accumulation of virus in intracellular compartments and significantly reduced viral trans-infection via the VS. By targeting endocytic trafficking and retromer recycling to the plasma membrane, we were able to reduce the virus's ability to accumulate at budding microdomains and the VS. Thus, we identify key genes involved in a pathway within DCs that is exploited by HIV-1 to traffic to the VS.IMPORTANCE The lentivirus human immunodeficiency virus (HIV) targets and destroys CD4+ T cells, leaving the host vulnerable to life-threatening opportunistic infections associated with AIDS. Dendritic cells (DCs) form a virological synapse (VS) with CD4+ T cells, enabling the efficient transfer of virus between the two cells. We have identified cellular factors that are critical in the induction of the VS. We show that ADP-ribosylation factor 1 (ARF1), bridging integrator 1 (BIN1), and Rab GTPases RAB7L1 and RAB8A are important regulators of HIV-1 trafficking to the VS and therefore the infection of CD4+ T cells. We found these cellular factors were essential for endosomal protein trafficking and formation of the VS and that depletion of target proteins prevented virus trafficking to the plasma membrane by retaining virus in intracellular vesicles. Identification of key regulators in HIV-1 trans-infection between DC and CD4+ T cells has the potential for the development of targeted therapy to reduce trans-infection of HIV-1 in vivo.


Assuntos
Células Dendríticas/imunologia , Infecções por HIV/genética , HIV-1/imunologia , Sinapses Imunológicas/metabolismo , Fator 1 de Ribosilação do ADP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/virologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Ensaios de Triagem em Larga Escala/métodos , Humanos , Monócitos/metabolismo , Proteínas Nucleares/metabolismo , Cultura Primária de Células , Transporte Proteico/genética , Proteínas Supressoras de Tumor/metabolismo , Vírion/metabolismo , Replicação Viral , Produtos do Gene gag do Vírus da Imunodeficiência Humana/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo
18.
PLoS One ; 15(1): e0227533, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978062

RESUMO

Envelope (Env) phenotype(s) that provide transmitted founders (TF) with a selective advantage during HIV-1 transmission would be the ideal target for preventative therapy. We generated Env clones from four individuals infected with a single virus and one participant infected with multiple variants at transmission and compared phenotype with matched Envs from chronic infection (CI). When we determined whether pseudovirus (PSV) of the five TF and thirteen matched CI Env clones differed in their ability to 1) enter TZM-bl cells, 2) bind DC-SIGN, and 3) trans-infect CD4+ cells there was no association between time post-infection and variation in Env phenotype. However, when we compared the ability of PSV to induce monocyte-derived dendritic cells (MDDCs) to secrete Interleukin-10 (IL-10), we found that only TF Envs from single variant transmission cases induced MDDCs to secrete either higher or similar levels of IL-10 as the CI clones. Furthermore, interaction between MDDC DC-SIGN and Env was required for secretion of IL-10. When variants were grouped according to time post-infection, TF PSV induced the release of higher levels of IL-10 than their CI counterparts although this relationship varied across MDDC donors. The selection of variants during transmission is therefore likely a complex event dependent on both virus and host genetics. Our findings suggest that, potentially due to overall variation in N-glycosylation across variants, nuanced differences in binding of TF Env to DC-SIGN might trigger alternative DC immune responses (IRs) in the female genital tract (FGT) that favour HIV-1 survival and facilitate transmission.


Assuntos
Células Dendríticas/metabolismo , Células Dendríticas/virologia , Variação Genética , HIV-1/genética , HIV-1/fisiologia , Interleucina-10/metabolismo , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Moléculas de Adesão Celular/metabolismo , Células Dendríticas/imunologia , Feminino , Glicosilação , Células HEK293 , HIV-1/imunologia , Humanos , Lectinas Tipo C/metabolismo , Fenótipo , Receptores de Superfície Celular/metabolismo , Vacinas de DNA/imunologia , Internalização do Vírus , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
19.
Mol Cell Biochem ; 464(1-2): 169-180, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31758375

RESUMO

Dengue, caused by dengue virus (DENV) infection, is a public health problem worldwide. Although DENV pathogenesis has not yet been fully elucidated, the inflammatory response is a hallmark feature in severe DENV infection. Although vitamin D (vitD) can promote the innate immune response against virus infection, no studies have evaluated the effects of vitD on DENV infection, dendritic cells (DCs), and inflammatory response regulation. This study aimed to assess the impact of oral vitD supplementation on DENV-2 infection, Toll-like receptor (TLR) expression, and both pro- and anti-inflammatory cytokine production in monocyte-derived DCs (MDDCs). To accomplish this, 20 healthy donors were randomly divided into two groups and received either 1000 or 4000 international units (IU)/day of vitD for 10 days. During pre- and post-vitD supplementation, peripheral blood samples were taken to obtain MDDCs, which were challenged with DENV-2. We found that MDDCs from donors who received 4000 IU/day of vitD were less susceptible to DENV-2 infection than MDDCs from donors who received 1000 IU/day of vitD. Moreover, these cells showed decreased mRNA expression of TLR3, 7, and 9; downregulation of IL-12/IL-8 production; and increased IL-10 secretion in response to DENV-2 infection. In conclusion, the administration of 4000 IU/day of vitD decreased DENV-2 infection. Our findings support a possible role of vitD in improving the innate immune response against DENV. However, further studies are necessary to determine the role of vitD on DENV replication and its innate immune response modulation in MDDCs.


Assuntos
Citocinas/imunologia , Células Dendríticas/imunologia , Vírus da Dengue/fisiologia , Dengue/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores Toll-Like/imunologia , Replicação Viral/efeitos dos fármacos , Vitamina D/farmacologia , Adulto , Células Dendríticas/patologia , Células Dendríticas/virologia , Dengue/tratamento farmacológico , Dengue/patologia , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Masculino , Replicação Viral/imunologia
20.
Infect Immun ; 88(2)2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31740528

RESUMO

Influenza A virus (H1N1) is an acute, highly contagious respiratory virus. The use of lactic acid bacteria (LAB) to deliver mucosal vaccines against influenza virus infection is a research hot spot. In this study, two recombinant Lactobacillus plantarum strains expressing hemagglutinin (HA) alone or coexpressing aCD11c-HA to target HA protein to dendritic cells (DCs) by fusion to an anti-CD11c single-chain antibody (aCD11c) were constructed. The activation of bone marrow dendritic cells (BMDCs) by recombinant strains and the interaction of activated BMDCs and sorted CD4+ or CD8+ T cells were evaluated through flow cytometry in vitro, and cellular supernatants were assessed by using an enzyme-linked immunosorbent assay kit. The results demonstrated that, compared to the HA strain, the aCD11c-HA strain significantly increased the activation of BMDCs and increased the production of CD4+ gamma interferon-positive (IFN-γ+) T cells, CD8+ IFN-γ+ T cells, and IFN-γ in the cell culture supernatant in vitro Consistent with these results, the aCD11c-HA strain clearly increased the activation and maturation of DCs, the HA-specific responses of CD4+ IFN-γ+ T cells, CD8+ IFN-γ+ T cells, and CD8+ CD107a+ T cells, and the proliferation of T cells in the spleen, finally increasing the levels of specific antibodies and neutralizing antibodies in mice. In addition, the protection of immunized mice was observed after viral infection, as evidenced by improved weight loss, survival, and lung pathology. The adoptive transfer of CD8+ T cells from the aCD11c-HA mice to NOD/Lt-SCID mice resulted in a certain level of protection after influenza virus infection, highlighting the efficacy of the aCD11c targeting strategy.


Assuntos
Antígeno CD11c/imunologia , Células Dendríticas/imunologia , Imunidade Celular/imunologia , Lactobacillus plantarum/imunologia , Anticorpos de Cadeia Única/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Células Dendríticas/virologia , Feminino , Vírus da Influenza A Subtipo H1N1/imunologia , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia
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