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1.
Int J Mol Sci ; 21(18)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933166

RESUMO

The glycans on enveloped viruses are synthesized by host-cell machinery. Some of these glycans on zoonotic viruses of mammalian reservoirs are recognized by human natural antibodies that may protect against such viruses. These antibodies are produced mostly against carbohydrate antigens on gastrointestinal bacteria and fortuitously, they bind to carbohydrate antigens synthesized in other mammals, neutralize and destroy viruses presenting these antigens. Two such antibodies are: anti-Gal binding to α-gal epitopes synthesized in non-primate mammals, lemurs, and New World monkeys, and anti-N-glycolyl neuraminic acid (anti-Neu5Gc) binding to N-glycolyl-neuraminic acid (Neu5Gc) synthesized in apes, Old World monkeys, and many non-primate mammals. Anti-Gal appeared in Old World primates following accidental inactivation of the α1,3galactosyltransferase gene 20-30 million years ago. Anti-Neu5Gc appeared in hominins following the inactivation of the cytidine-monophosphate-N-acetyl-neuraminic acid hydroxylase gene, which led to the loss of Neu5Gc <6 million-years-ago. It is suggested that an epidemic of a lethal virus eliminated ancestral Old World-primates synthesizing α-gal epitopes, whereas few mutated offspring lacking α-gal epitopes and producing anti-Gal survived because anti-Gal destroyed viruses presenting α-gal epitopes, following replication in parental populations. Similarly, anti-Neu5Gc protected few mutated hominins lacking Neu5Gc in lethal virus epidemics that eliminated parental hominins synthesizing Neu5Gc. Since α-gal epitopes are presented on many zoonotic viruses it is suggested that vaccines elevating anti-Gal titers may be of protective significance in areas endemic for such zoonotic viruses. This protection would be during the non-primate mammal to human virus transmission, but not in subsequent human to human transmission where the virus presents human glycans. In addition, production of viral vaccines presenting multiple α-gal epitopes increases their immunogenicity because of effective anti-Gal-mediated targeting of vaccines to antigen presenting cells for extensive uptake of the vaccine by these cells.


Assuntos
Antígenos Virais/imunologia , Glicoproteínas/imunologia , Viroses/imunologia , Animais , Reações Antígeno-Anticorpo , Evolução Molecular , Galactosiltransferases/genética , Galactosiltransferases/metabolismo , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Primatas
2.
J Clin Virol ; 129: 104544, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32663788

RESUMO

The emergence of the severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) has been followed by the rapid development of antibody tests. To assess the utility of the tests for clinical use and seroepidemiologic studies, we examined the sensitivity of commercial antibody tests from Roche, Abbott, Novatec, Virotech Siemens, Euroimmun, and Mediagnost in a prospective diagnostic study. The tests were evaluated with 73 sera from SARS CoV-2 RNA positive individuals with mild to moderate disease or asymptomatic infection. Sera were obtained at 2-3 weeks (N = 25) or > 4 weeks (N = 48) after symptom onset and viral RNA test. The overall sensitivity of the tests ranged from 64.4-93.2%. The most sensitive assays recognized 95.8-100 % of the sera obtained after 4 weeks or later. Sera drawn at 2-3 weeks were recognized with lower sensitivity indicating that the optimal time point for serologic testing is later than 3 weeks after onset of the disease. Nucleoprotein- and glycoproteinbased assays had similar sensitivity indicating that tests with both antigens are suitable for serological diagnostics. Breakdown of the test results showed that nucleoprotein- and glycoprotein-based tests of comparable sensitivity reacted with different sets of sera. The observation indicates that a combination of nucleoprotein- and glycoprotein-based tests would increase the percentage of positive results.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Testes Sorológicos/métodos , Proteínas Estruturais Virais/imunologia , Betacoronavirus/imunologia , Glicoproteínas/imunologia , Humanos , Nucleoproteínas/imunologia , Pandemias , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores de Tempo
4.
Parasitol Res ; 119(8): 2521-2529, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32591864

RESUMO

The enzyme-linked immunoelectrotransfer blot (EITB) assay to detect antibodies in serum is a complementary tool for the diagnosis of neurocysticercosis (NCC). Presence of at least one glycoprotein band corresponding to a Taenia solium (T. solium) antigen indicates a positive result; however, EITB assays have multiple glycoprotein bands, and previous work has suggested that band patterns may have additional diagnostic value. We included 58 participants with a definitive diagnosis of NCC who received care at the Instituto Nacional de Neurología y Neurocirugía in Mexico City. Three different EITB tests were applied to participants' serum samples (LDBio, France; US Centers for Disease Control and Prevention [CDC]; and Instituto de Diagnóstico y Referencia Epidemiológicos [InDRE]). There was substantial variability in specific glycoprotein band patterns among the three assays. However, in age- and sex-adjusted logistic regression models, the number of glycoprotein bands was positively associated with the presence of vesicular extraparenchymal cysts (InDRE adjusted odds ratio [aOR] 1.60 p < 0.001; CDC aOR 6.31 p < 0.001; LDBio aOR 2.45 p < 0.001) and negatively associated with the presence of calcified parenchymal cysts (InDRE aOR 0.63 p < 0.001; CDC aOR 0.25 p < 0.001; LDBio aOR 0.44 p < 0.001). In a sensitivity analysis also adjusting for cyst count, results were similar. In all three EITB serum antibody tests, the number of glycoprotein bands consistently predicted cyst stage and location, although magnitude of effect differed.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Glicoproteínas/análise , Proteínas de Helminto/análise , Neurocisticercose/diagnóstico , Taenia solium/isolamento & purificação , Animais , Anticorpos Anti-Helmínticos/análise , Antígenos de Helmintos/análise , Antígenos de Helmintos/imunologia , Feminino , França , Glicoproteínas/imunologia , Proteínas de Helminto/imunologia , Humanos , Masculino , México , Neurocisticercose/parasitologia , Razão de Chances , Sensibilidade e Especificidade , Taenia solium/crescimento & desenvolvimento , Taenia solium/imunologia
5.
Eur J Pharm Sci ; 151: 105387, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32454128

RESUMO

The emergence and rapid expansion of the coronavirus disease (COVID-19) require the development of effective countermeasures especially a vaccine to provide active acquired immunity against the virus. This study presented a comprehensive vaccinomics approach applied to the complete protein data published so far in the National Center for Biotechnological Information (NCBI) coronavirus data hub. We identified non-structural protein 8 (Nsp8), 3C-like proteinase, and spike glycoprotein as potential targets for immune responses to COVID-19. Epitopes prediction illustrated both B-cell and T-cell epitopes associated with the mentioned proteins. The shared B and T-cell epitopes: DRDAAMQRK and QARSEDKRA of Nsp8, EDMLNPNYEDL and EFTPFDVVR of 3C-like proteinase, and VNNSYECDIPI of the spike glycoprotein are regions of high potential interest and have a high likelihood of being recognized by the human immune system. The vaccine construct of the epitopes shows stimulation of robust primary immune responses and high level of interferon gamma. Also, the construct has the best conformation with respect to the tested innate immune receptors involving vigorous molecular mechanics and solvation energy. Designing of vaccination strategies that target immune response focusing on these conserved epitopes could generate immunity that not only provide cross protection across Betacoronaviruses but additionally resistant to virus evolution.


Assuntos
Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Desenho de Fármacos , Epitopos/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Zoonoses/imunologia , Sequência de Aminoácidos , Animais , Linfócitos B/imunologia , Mapeamento de Epitopos , Glicoproteínas/imunologia , Humanos , Modelos Moleculares , Simulação de Dinâmica Molecular , Receptores Imunológicos/química , Receptores Imunológicos/imunologia , Linfócitos T/imunologia , Proteínas não Estruturais Virais/imunologia , Proteínas Virais/química , Proteínas Virais/imunologia
6.
Nihon Yakurigaku Zasshi ; 155(3): 150-154, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32378633

RESUMO

Many strategies have been tried to produce monoclonal antibodies (mAbs); however, there have been several problems about focusing on molecular targets and screening methods. For instance, the high tumor/normal ratio of antigen expression using DNA microarray has been thought to be important when we determine the molecular targets for antibody-drug. Although many antigens are expressed highly in tumors, those antigens have been removed from the candidates of antibody-drug targets because they were also expressed in normal tissues. We recently established a novel technology to produce a cancer-specific monoclonal antibody (CasMab). The post-translational difference such as glycans can be utilized to produce the CasMab, although the protein possesses the same amino acid sequence in both cancer and normal cells. We have already produced CasMabs against several glycoproteins such as podoplanin, which is expressed in both cancer and normal cells. Those CasMabs possess antibody-dependent cellular cytotoxicity (ADCC) or complement-dependent cytotoxicity (CDC) in vitro and anti-tumor effect in xenograft models in vivo. In conclusion, the CasMab technology is the platform to develop cancer-specific mAbs, which could attack only cancer cells without side effects.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Antineoplásicos/farmacologia , Antígenos de Neoplasias/imunologia , Glicoproteínas/imunologia , Animais , Citotoxicidade Celular Dependente de Anticorpos , Humanos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Nat Commun ; 11(1): 2688, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32461612

RESUMO

Severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronaviruses (CoVs) are zoonotic pathogens with high fatality rates and pandemic potential. Vaccine development focuses on the principal target of the neutralizing humoral immune response, the spike (S) glycoprotein. Coronavirus S proteins are extensively glycosylated, encoding around 66-87 N-linked glycosylation sites per trimeric spike. Here, we reveal a specific area of high glycan density on MERS S that results in the formation of oligomannose-type glycan clusters, which were absent on SARS and HKU1 CoVs. We provide a comparison of the global glycan density of coronavirus spikes with other viral proteins including HIV-1 envelope, Lassa virus glycoprotein complex, and influenza hemagglutinin, where glycosylation plays a known role in shielding immunogenic epitopes. Overall, our data reveal how organisation of glycosylation across class I viral fusion proteins influence not only individual glycan compositions but also the immunological pressure across the protein surface.


Assuntos
Glicoproteínas/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio , Polissacarídeos , Glicoproteína da Espícula de Coronavírus/imunologia , Proteínas Virais de Fusão/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Microscopia Crioeletrônica , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Glicoproteínas/química , Glicoproteínas/ultraestrutura , Glicosilação , Células HEK293 , HIV-1/imunologia , HIV-1/metabolismo , Humanos , Evasão da Resposta Imune/fisiologia , Vírus Lassa/imunologia , Vírus Lassa/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Orthomyxoviridae/imunologia , Orthomyxoviridae/metabolismo , Polissacarídeos/química , Polissacarídeos/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/ultraestrutura , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/ultraestrutura , Proteínas Virais/química , Proteínas Virais/imunologia , Proteínas Virais/ultraestrutura
8.
Am J Trop Med Hyg ; 103(1_Suppl): 50-57, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400344

RESUMO

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was funded in 2008 to conduct research that would support country schistosomiasis control programs. As schistosomiasis prevalence decreases in many places and elimination is increasingly within reach, a sensitive and specific test to detect infection with Schistosoma mansoni and Schistosoma haematobium has become a pressing need. After obtaining broad input, SCORE supported Leiden University Medical Center (LUMC) to modify the serum-based antigen assay for use with urine, simplify the assay, and improve its sensitivity. The urine assay eventually contributed to several of the larger SCORE studies. For example, in Zanzibar, we demonstrated that urine filtration, the standard parasite egg detection diagnostic test for S. haematobium, greatly underestimated prevalence in low-prevalence settings. In Burundi and Rwanda, the circulating anodic antigen (CAA) assay provided critical information about the limitations of the stool-based Kato-Katz parasite egg-detection assay for S. mansoni in low-prevalence settings. Other SCORE-supported CAA work demonstrated that frozen, banked urine specimens yielded similar results to fresh ones; pooling of specimens may be a useful, cost-effective approach for surveillance in some settings; and the assay can be performed in local laboratories equipped with adequate centrifuge capacity. These improvements in the assay continue to be of use to researchers around the world. However, additional work will be needed if widespread dissemination of the CAA assay is to occur, for example, by building capacity in places besides LUMC and commercialization of the assay. Here, we review the evolution of the CAA assay format during the SCORE period with emphasis on urine-based applications.


Assuntos
Antígenos de Helmintos/imunologia , Glicoproteínas/imunologia , Proteínas de Helminto/imunologia , Schistosoma/imunologia , Esquistossomose/diagnóstico , Animais , Biomarcadores , Burundi/epidemiologia , Criança , Testes Diagnósticos de Rotina , Fezes/parasitologia , Feminino , Humanos , Testes Imunológicos , Masculino , Modelos Animais , Papio/parasitologia , Contagem de Ovos de Parasitas , Prevalência , Ruanda/epidemiologia , Santa Lúcia/epidemiologia , Schistosoma/isolamento & purificação , Schistosoma haematobium/imunologia , Schistosoma haematobium/isolamento & purificação , Schistosoma japonicum/imunologia , Schistosoma japonicum/isolamento & purificação , Schistosoma mansoni/imunologia , Schistosoma mansoni/isolamento & purificação , Esquistossomose/epidemiologia , Sensibilidade e Especificidade , Tanzânia/epidemiologia , Urina/parasitologia
9.
Am J Trop Med Hyg ; 103(1_Suppl): 125-134, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400345

RESUMO

Herein, we summarize what we consider are major contributions resulting from the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) program, including its key findings and key messages from those findings. Briefly, SCORE's key findings are as follows: i) biennial mass drug administration (MDA) with praziquantel can control schistosomiasis to moderate levels of prevalence; ii) MDA alone will not achieve elimination; iii) to attain and sustain control throughout endemic areas, persistent hotspots need to be identified following a minimal number of years of annual MDA and controlled through adaptive strategies; iv) annual MDA is more effective than biennial MDA in high-prevalence areas; v) the current World Health Organization thresholds for decision-making based on the prevalence of heavy infections should be redefined; and vi) point-of-care circulating cathodic antigen urine assays are useful for Schistosoma mansoni mapping in low-to-moderate prevalence areas. The data and specimens collected and curated through SCORE efforts will continue to be critical resource for future research. Besides providing useful information for program managers and revision of guidelines for schistosomiasis control and elimination, SCORE research and outcomes have identified additional questions that need to be answered as the schistosomiasis community continues to implement effective, evidence-based programs. An overarching contribution of SCORE has been increased cohesiveness within the schistosomiasis field-oriented community, thereby fostering new and productive collaborations. Based on SCORE's findings and experiences, we propose new approaches, thresholds, targets, and goals for control and elimination of schistosomiasis, and recommend research and evaluation activities to achieve these targets and goals.


Assuntos
Diretrizes para o Planejamento em Saúde , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose/prevenção & controle , África/epidemiologia , Animais , Anti-Helmínticos/uso terapêutico , Antígenos de Helmintos/imunologia , Biomarcadores/sangue , Criança , Fezes/parasitologia , Glicoproteínas/imunologia , Proteínas de Helminto/imunologia , Humanos , Masculino , Administração Massiva de Medicamentos , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/prevenção & controle , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Prevalência , Saúde Pública , Esquistossomose/diagnóstico , Esquistossomose/tratamento farmacológico , Esquistossomose/epidemiologia , Esquistossomose mansoni/diagnóstico , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/prevenção & controle
10.
Am J Trop Med Hyg ; 103(1_Suppl): 42-49, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400347

RESUMO

Efforts to control Schistosoma mansoni infection depend on the ability of programs to effectively detect and quantify infection levels and adjust programmatic approaches based on these levels and program goals. One of the three major objectives of the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) has been to develop and/or evaluate tools that would assist Neglected Tropical Disease program managers in accomplishing this fundamental task. The advent of a widely available point-of-care (POC) assay to detect schistosome circulating cathodic antigen (CCA) in urine with a rapid diagnostic test (the POC-CCA) in 2008 led SCORE and others to conduct multiple evaluations of this assay, comparing it with the Kato-Katz (KK) stool microscopy assay-the standard used for more than 45 years. This article describes multiple SCORE-funded studies comparing the POC-CCA and KK assays, the pros and cons of these assays, the use of the POC-CCA assay for mapping of S. mansoni infections in areas across the spectrum of prevalence levels, and the validation and recognition that the POC-CCA, although not infallible, is a highly useful tool to detect low-intensity infections in low-to-moderate prevalence areas. Such an assay is critical, as control programs succeed in driving down prevalence and intensity and seek to either maintain control or move to elimination of transmission of S. mansoni.


Assuntos
Antígenos de Helmintos/imunologia , Glicoproteínas/imunologia , Proteínas de Helminto/imunologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/diagnóstico , Animais , Criança , Testes Diagnósticos de Rotina , Fezes/parasitologia , Feminino , Humanos , Testes Imunológicos , Masculino , Sistemas Automatizados de Assistência Junto ao Leito , Prevalência , Esquistossomose mansoni/epidemiologia , Sensibilidade e Especificidade , Urina/parasitologia
11.
Int J Infect Dis ; 95: 276-278, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32289563

RESUMO

OBJECTIVES: This study was performed to determine whether Dengue virus (DENV) immunochromatographic tests can detect and differentiate nonstructural protein 1 (NS1) from each of the four DENV serotypes and do not cross-react with the Zika virus (ZIKV) NS1 protein. METHODS: We compared the specificity of six NS1-based DENV immunochromatographic tests (point of care) in the detection of NS1 proteins from each of the four DENV serotypes and ZIKV. The tests were performed with NS1 proteins produced in mammalian cells. Cross-reactivity was confirmed with a purified recombinant ZIKV NS1 protein and DENV+ or ZIKV+ human serum samples. RESULTS: Cross-reaction was observed in 2 out of the 6 evaluated tests using cell culture supernatants containing NS1 protein of each tested virus. Cross-reactivity with ZIKV was confirmed with purified recombinant ZIKV NS1 produced in Escherichia coli. Further analyses with serum samples collected from DENV+ or ZIKV+ patients confirmed the cross-reactivity with ZIKV protein in 2 tests. CONCLUSIONS: The detection of the NS1 protein is the basis for several commercially available serological DENV diagnostic tests. The present results emphasize the relevance of testing specificity of presently available NS1-based DENV serological tests and the need of adjustments of tests that cross-react with the ZIKV protein. Our results are particularly relevant for regions where both viruses are endemically found, as in the case of Brazil.


Assuntos
Cromatografia de Afinidade/métodos , Vírus da Dengue/imunologia , Dengue/virologia , Proteínas não Estruturais Virais/imunologia , Zika virus/imunologia , Anticorpos Antivirais/sangue , Brasil , Reações Cruzadas , Vírus da Dengue/isolamento & purificação , Glicoproteínas/imunologia , Humanos , Sensibilidade e Especificidade , Especificidade da Espécie
12.
PLoS Negl Trop Dis ; 14(3): e0008143, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32160203

RESUMO

Rift Valley fever virus (RVFV) is a zoonotic arbovirus that causes severe disease in humans and ruminants. The infection is characterized by abortions in pregnant animals, high mortality in neonates as well as febrile illness in humans that develop in 1% of cases encephalitis or hemorrhagic fever. There is presently no specific antiviral treatment for RVFV infection available. In this study, two monoclonal antibodies (mAbs), raised against glycoprotein Gn, were applied in a therapeutic study. Treatment of RVFV infected mice with neutralizing mAb Gn3 alone at two different time points (30 minutes before or 30 minutes after virus challenge) showed only moderate efficacy of about 58.3% survival in both applications. However, a combination therapy together with non-neutralizing mAb Gn32 demonstrated complete protection (100% survival) when applied 30 minutes after the lethal challenge dose. The increase of mAb efficacy is probably based on cooperative neutralization effects. These data suggest that a combination therapy with mAbs Gn3 and Gn32 could be an effective treatment option against RVFV infection.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Fatores Imunológicos/administração & dosagem , Febre do Vale de Rift/prevenção & controle , Animais , Antígenos Virais/imunologia , Modelos Animais de Doenças , Feminino , Glicoproteínas/imunologia , Masculino , Camundongos Endogâmicos BALB C , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Análise de Sobrevida , Resultado do Tratamento
13.
Arch Virol ; 165(5): 1109-1120, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32189084

RESUMO

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease with a mortality rate of up to 50% in humans. To avoid safety concerns associated with the use of live virus in virus neutralization assays and to detect human serum neutralizing antibodies, we prepared lentiviral particles containing the CCHF glycoprotein (lenti-CCHFV-GP). Incorporation of the GP into the lentiviral particle was confirmed by electron microscopy and Western blotting. Lenti-CCHFV-GP was found to be able to infect a wide range of cell lines, including BHK-21, HeLa, HepG2, and AsPC-1 cells. In addition, lenti-CCHFV-GP was successfully used as an alternative to CCHFV for the detection of neutralizing antibodies. Sera collected from CCHF survivors neutralized lenti-CCHFV-GP particles in a dose-dependent manner. Our results suggest that the lenti-CCHFV-GP pseudovirus can be used as a safe tool for neutralization assays in low-containment laboratories.


Assuntos
Técnicas de Visualização da Superfície Celular , Glicoproteínas/imunologia , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Lentivirus/crescimento & desenvolvimento , Testes de Neutralização/métodos , Proteínas Virais/imunologia , Internalização do Vírus , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Linhagem Celular , Vetores Genéticos , Glicoproteínas/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Especificidade de Hospedeiro , Humanos , Lentivirus/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Virais/genética
15.
J Biomed Sci ; 27(1): 33, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32059697

RESUMO

Vaccination is the most effective measure at preventing influenza virus infections. However, current seasonal influenza vaccines are only protective against closely matched circulating strains. Even with extensive monitoring and annual reformulation our efforts remain one step behind the rapidly evolving virus, often resulting in mismatches and low vaccine effectiveness. Fortunately, many next-generation influenza vaccines are currently in development, utilizing an array of innovative techniques to shorten production time and increase the breadth of protection. This review summarizes the production methods of current vaccines, recent advances that have been made in influenza vaccine research, and highlights potential challenges that are yet to be overcome. Special emphasis is put on the potential role of glycoengineering in influenza vaccine development, and the advantages of removing the glycan shield on influenza surface antigens to increase vaccine immunogenicity. The potential for future development of these novel influenza vaccine candidates is discussed from an industry perspective.


Assuntos
Glicoproteínas/imunologia , Imunogenicidade da Vacina , Vacinas contra Influenza/imunologia , Engenharia de Proteínas , Proteínas Virais/imunologia , Glicoproteínas/química , Glicoproteínas/farmacologia , Glicosilação , Humanos , Vacinas contra Influenza/análise , Vacinas contra Influenza/química , Vacinas contra Influenza/farmacologia , Proteínas Virais/química , Proteínas Virais/farmacologia
16.
J Virol ; 94(8)2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32051271

RESUMO

Given that the Ebola virus (EBOV) infects a wide array of organs and cells yet displays a relative lack of neurotropism, we asked whether a chimeric vesicular stomatitis virus (VSV) expressing the EBOV glycoprotein (GP) might selectively target brain tumors. The mucin-like domain (MLD) of the EBOV GP may enhance virus immune system evasion. Here, we compared chimeric VSVs in which EBOV GP replaces the VSV glycoprotein, thereby reducing the neurotoxicity associated with wild-type VSV. A chimeric VSV expressing the full-length EBOV GP (VSV-EBOV) containing the MLD was substantially more effective and safer than a parallel construct with an EBOV GP lacking the MLD (VSV-EBOVΔMLD). One-step growth, reverse transcription-quantitative PCR, and Western blotting assessments showed that VSV-EBOVΔMLD produced substantially more progeny faster than VSV-EBOV. Using immunodeficient SCID mice, we focused on targeting human brain tumors with these VSV-EBOVs. Similar to the findings of our previous study in which we used an attenuated VSV-EBOV with no MLD that expressed green fluorescent protein (GFP) (VSV-EBOVΔMLD-GFP), VSV-EBOVΔMLD without GFP targeted glioma but yielded only a modest extension of survival. In contrast, VSV-EBOV containing the MLD showed substantially better targeting and elimination of brain tumors after intravenous delivery and increased the survival of brain tumor-bearing mice. Despite the apparent destruction of most tumor cells by VSV-EBOVΔMLD, the virus remained active within the SCID mouse brain and showed widespread infection of normal brain cells. In contrast, VSV-EBOV eliminated the tumors and showed relatively little infection of normal brain cells. Parallel experiments with direct intracranial virus infection generated similar results. Neither VSV-EBOV nor VSV-EBOVΔMLD showed substantive infection of the brains of normal immunocompetent mice.IMPORTANCE The Ebola virus glycoprotein contains a mucin-like domain which may play a role in immune evasion. Chimeric vesicular stomatitis viruses with the EBOV glycoprotein substituted for the VSV glycoprotein show greater safety and efficacy in targeting brain tumors in immunodeficient mice when the MLD was expressed within the EBOV glycoprotein than when EBOV lacked the mucin-like domain.


Assuntos
Neoplasias Encefálicas/metabolismo , Ebolavirus/imunologia , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/virologia , Mucinas/imunologia , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ebolavirus/genética , Glioblastoma/virologia , Glioma/patologia , Glioma/virologia , Proteínas de Fluorescência Verde , Xenoenxertos , Humanos , Camundongos , Camundongos SCID , Mucinas/genética , Vírus da Estomatite Vesicular Indiana/imunologia
17.
Proc Natl Acad Sci U S A ; 117(7): 3768-3778, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32015126

RESUMO

Antibody-based therapies are a promising treatment option for managing ebolavirus infections. Several Ebola virus (EBOV)-specific and, more recently, pan-ebolavirus antibody cocktails have been described. Here, we report the development and assessment of a Sudan virus (SUDV)-specific antibody cocktail. We produced a panel of SUDV glycoprotein (GP)-specific human chimeric monoclonal antibodies (mAbs) using both plant and mammalian expression systems and completed head-to-head in vitro and in vivo evaluations. Neutralizing activity, competitive binding groups, and epitope specificity of SUDV mAbs were defined before assessing protective efficacy of individual mAbs using a mouse model of SUDV infection. Of the mAbs tested, GP base-binding mAbs were more potent neutralizers and more protective than glycan cap- or mucin-like domain-binding mAbs. No significant difference was observed between plant and mammalian mAbs in any of our in vitro or in vivo evaluations. Based on in vitro and rodent testing, a combination of two SUDV-specific mAbs, one base binding (16F6) and one glycan cap binding (X10H2), was down-selected for assessment in a macaque model of SUDV infection. This cocktail, RIID F6-H2, provided protection from SUDV infection in rhesus macaques when administered at 50 mg/kg on days 4 and 6 postinfection. RIID F6-H2 is an effective postexposure SUDV therapy and provides a potential treatment option for managing human SUDV infection.


Assuntos
Anticorpos Antivirais/administração & dosagem , Ebolavirus/imunologia , Doença pelo Vírus Ebola/tratamento farmacológico , Animais , Anticorpos Monoclonais/administração & dosagem , Modelos Animais de Doenças , Ebolavirus/genética , Feminino , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/virologia , Humanos , Imunoterapia , Macaca mulatta , Masculino , Camundongos , Proteínas Virais/imunologia
18.
J Gen Virol ; 101(4): 440-452, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32003709

RESUMO

We report the isolation of Australian strains of Bustos virus and Ngewotan virus, two insect-specific viruses in the newly identified taxon Negevirus, originally isolated from Southeast Asian mosquitoes. Consistent with the expected insect-specific tropism of negeviruses, these isolates of Ngewotan and Bustos viruses, alongside the Australian negevirus Castlerea virus, replicated exclusively in mosquito cells but not in vertebrate cells, even when their temperature was reduced to 34 °C. Our data confirmed the existence of two structural proteins, putatively one membrane protein forming the majority of the virus particle, and one glycoprotein forming a projection on the apex of the virions. We generated and characterized 71 monoclonal antibodies to both structural proteins of the two viruses, most of which were neutralizing. Overall, these data increase our knowledge of negevirus mechanisms of infection and replication in vitro.


Assuntos
Anticorpos Monoclonais/imunologia , Culicidae/virologia , Vírus de Insetos/fisiologia , Proteínas Estruturais Virais/imunologia , Vírion/metabolismo , Replicação Viral/genética , Animais , Austrália , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Genoma Viral , Glicoproteínas/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Especificidade de Hospedeiro/fisiologia , Hibridomas/imunologia , Vírus de Insetos/genética , Vírus de Insetos/imunologia , Vírus de Insetos/isolamento & purificação , Proteínas de Membrana/imunologia , Microscopia Eletrônica , Filogenia , Células Vero , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/metabolismo , Vírion/ultraestrutura
19.
Allergol. immunopatol ; 48(1): 67-72, ene.-feb. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-186594

RESUMO

Background: There is little understanding of the mechanisms by which food allergy (FA) develops into persistent disease, or by which symptoms it regresses. Food allergy is a major health problem in developed countries, where the prevalence reaches up to 6% in children and 3% in the adult population. Objective: Children with food allergy remission (FAR) and those without FAR below five years of age, were compared 7-10 years with respect to clinical data and expression of glycoprotein A repetitions predominant (GARP) on peripheral blood mononuclear cells. Methods: Forty children with FAR and 40 children without FAR at age 7-10, in whom FA was previously diagnosed at age below five years were evaluated. In this prospective study, demographic and clinical data were taken, patients were classified as atopic based on history and serum specific IgE (sIgE) for a specific allergen. Blood samples were obtained from all patients to assess expression of GARP. Results: We observed higher expression of GARP in children with FAR compared to children without FA (p = 0.005); optimal cut-off for GARP prediction of the remission was 20.1%. Children with FAR and food-specific IgE in serum had higher expression of GARP compared to children with low food specific IgE (< 0.35 kU/L). Keeping pets at home decreased, and presence of allergic rhinitis increased ORs for high expression of GARP (hGARP) in our patients. Conclusion: hGARP (>20.1%) is related with FAR in school children. Allergic rhinitis, and pets at home modify this effect of GARP. Children with allergic rhinitis have less chance of developing remission despite maintaining immune tolerance (hGARP); quite the opposite case with pets at home


No disponible


Assuntos
Humanos , Criança , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/sangue , Fatores de Transcrição , Glicoproteínas/imunologia , Hipersensibilidade Alimentar/imunologia , Imunoglobulina E/imunologia , Leucócitos Mononucleares/imunologia , Rinite Alérgica , Hipersensibilidade Alimentar/sangue , Estudos Prospectivos , Modelos Logísticos , Glicoproteínas/metabolismo
20.
Lancet Infect Dis ; 20(4): 445-454, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32027842

RESUMO

BACKGROUND: The monoclonal antibody m102.4 is a potent, fully human antibody that neutralises Hendra and Nipah viruses in vitro and in vivo. We aimed to investigate the safety, tolerability, pharmacokinetics, and immunogenicity of m102.4 in healthy adults. METHODS: In this double-blind, placebo-controlled, single-centre, dose-escalation, phase 1 trial of m102.4, we randomly assigned healthy adults aged 18-50 years with a body-mass index of 18·0-35·0 kg/m2 to one of five cohorts. A sentinel pair for each cohort was randomly assigned to either m102.4 or placebo. The remaining participants in each cohort were randomly assigned (5:1) to receive m102.4 or placebo. Cohorts 1-4 received a single intravenous infusion of m102.4 at doses of 1 mg/kg (cohort 1), 3 mg/kg (cohort 2), 10 mg/kg (cohort 3), and 20 mg/kg (cohort 4), and were monitored for 113 days. Cohort 5 received two infusions of 20 mg/kg 72 h apart and were monitored for 123 days. The primary outcomes were safety and tolerability. Secondary outcomes were pharmacokinetics and immunogenicity. Analyses were completed according to protocol. The study was registered on the Australian New Zealand Clinical Trials Registry, ACTRN12615000395538. FINDINGS: Between March 27, 2015, and June 16, 2016, 40 (52%) of 77 healthy screened adults were enrolled in the study. Eight participants were assigned to each cohort (six received m102.4 and two received placebo). 86 treatment-emergent adverse events were reported, with similar rates between placebo and treatment groups. The most common treatment-related event was headache (12 [40%] of 30 participants in the combined m102.4 group, and three [30%] of ten participants in the pooled placebo group). No deaths or severe adverse events leading to study discontinuation occurred. Pharmacokinetics based on those receiving m102.4 (n=30) were linear, with a median half-life of 663·3 h (range 474·3-735·1) for cohort 1, 466·3 h (382·8-522·3) for cohort 2, 397·0 h (333·9-491·8) for cohort 3, and 466·7 h (351·0-889·6) for cohort 4. The elimination kinetics of those receiving repeated dosing (cohort 5) were similar to those of single-dose recipients (median elimination half-time 472·0 [385·6-592·0]). Anti-m102.4 antibodies were not detected at any time-point during the study. INTERPRETATION: Single and repeated dosing of m102.4 were well tolerated and safe, displayed linear pharmacokinetics, and showed no evidence of an immunogenic response. This study will inform future dosing regimens for m102.4 to achieve prolonged exposure for systemic efficacy to prevent and treat henipavirus infections. FUNDING: Queensland Department of Health, the National Health and Medical Research Council, and the National Hendra Virus Research Program.


Assuntos
Anticorpos Monoclonais Humanizados/farmacocinética , Glicoproteínas/imunologia , Voluntários Saudáveis , Henipavirus/imunologia , Imunogenicidade da Vacina , Segurança , Adulto , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/imunologia , Austrália , Método Duplo-Cego , Feminino , Cefaleia/etiologia , Humanos , Infusões Intravenosas , Masculino
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