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1.
Sci Rep ; 10(1): 16219, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004978

RESUMO

COVID-19 pandemic has resulted in 16,114,449 cases with 646,641 deaths from the 217 countries, or territories as on July 27th 2020. Due to multifaceted issues and challenges in the implementation of the safety and preventive measures, inconsistent coordination between societies-governments and most importantly lack of specific vaccine to SARS-CoV-2, the spread of the virus that initially emerged at Wuhan is still uprising after taking a heavy toll on human life. In the present study, we mapped immunogenic epitopes present on the four structural proteins of SARS-CoV-2 and we designed a multi-epitope peptide based vaccine that, demonstrated a high immunogenic response with a vast application on world's human population. On codon optimization and in-silico cloning, we found that candidate vaccine showed high expression in E. coli and immune simulation resulted in inducing a high level of both B-cell and T-cell mediated immunity. The results predicted that exposure of vaccine by administrating three injections significantly subsidized the antigen growth in the system. The proposed candidate vaccine found promising by yielding desired results and hence, should be validated by practical experimentations for its functioning and efficacy to neutralize SARS-CoV-2.


Assuntos
Epitopos/imunologia , Simulação de Acoplamento Molecular , Vacinas de Subunidades/imunologia , Vacinas Virais/imunologia , Complexo Antígeno-Anticorpo/química , Complexo Antígeno-Anticorpo/imunologia , Antígenos Virais/imunologia , Linfócitos B/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Epitopos/química , Antígenos HLA/química , Antígenos HLA/imunologia , Humanos , Imunogenicidade da Vacina , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Receptores Toll-Like/imunologia , Vacinas de Subunidades/química , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/imunologia , Vacinas Virais/química
3.
Pharm Res ; 37(11): 212, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025261

RESUMO

PURPOSE: Coronavirus disease 2019 (COVID-19) is expected to continue to cause worldwide fatalities until the World population develops 'herd immunity', or until a vaccine is developed and used as a prevention. Meanwhile, there is an urgent need to identify alternative means of antiviral defense. Bacillus Calmette-Guérin (BCG) vaccine that has been recognized for its off-target beneficial effects on the immune system can be exploited to boast immunity and protect from emerging novel viruses. METHODS: We developed and employed a systems biology workflow capable of identifying small-molecule antiviral drugs and vaccines that can boast immunity and affect a wide variety of viral disease pathways to protect from the fatal consequences of emerging viruses. RESULTS: Our analysis demonstrates that BCG vaccine affects the production and maturation of naïve T cells resulting in enhanced, long-lasting trained innate immune responses that can provide protection against novel viruses. We have identified small-molecule BCG mimics, including antiviral drugs such as raltegravir and lopinavir as high confidence hits. Strikingly, our top hits emetine and lopinavir were independently validated by recent experimental findings that these compounds inhibit the growth of SARS-CoV-2 in vitro. CONCLUSIONS: Our results provide systems biology support for using BCG and small-molecule BCG mimics as putative vaccine and drug candidates against emergent viruses including SARS-CoV-2.


Assuntos
Vacina BCG/administração & dosagem , Materiais Biomiméticos/administração & dosagem , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Reposicionamento de Medicamentos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Bibliotecas de Moléculas Pequenas/administração & dosagem , Vacinas Virais/administração & dosagem , Vacina BCG/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/mortalidade , Humanos , Imunidade Inata , Pneumonia Viral/imunologia , Pneumonia Viral/mortalidade , Biologia de Sistemas/métodos , Vacinas Virais/imunologia , Fluxo de Trabalho
4.
Front Immunol ; 11: 2008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013857

RESUMO

Coronavirus disease (COVID-19), caused by the virus SARS-CoV-2, is already responsible for more than 4.3 million confirmed cases and 295,000 deaths worldwide as of May 15, 2020. Ongoing efforts to control the pandemic include the development of peptide-based vaccines and diagnostic tests. In these approaches, HLA allelic diversity plays a crucial role. Despite its importance, current knowledge of HLA allele frequencies in South America is very limited. In this study, we have performed a literature review of datasets reporting HLA frequencies of South American populations, available in scientific literature and/or in the Allele Frequency Net Database. This allowed us to enrich the current scenario with more than 12.8 million data points. As a result, we are presenting updated HLA allelic frequencies based on country, including 91 alleles that were previously thought to have frequencies either under 5% or of an unknown value. Using alleles with an updated frequency of at least ≥5% in any South American country, we predicted epitopes in SARS-CoV-2 proteins using NetMHCpan (I and II) and MHC flurry. Then, the best predicted epitopes (class-I and -II) were selected based on their binding to South American alleles (Coverage Score). Class II predicted epitopes were also filtered based on their three-dimensional exposure. We obtained 14 class-I and four class-II candidate epitopes with experimental evidence (reported in the Immune Epitope Database and Analysis Resource), having good coverage scores for South America. Additionally, we are presenting 13 HLA-I and 30 HLA-II novel candidate epitopes without experimental evidence, including 16 class-II candidates in highly exposed conserved areas of the NTD and RBD regions of the Spike protein. These novel candidates have even better coverage scores for South America than those with experimental evidence. Finally, we show that recent similar studies presenting candidate epitopes also predicted some of our candidates but discarded them in the selection process, resulting in candidates with suboptimal coverage for South America. In conclusion, the candidate epitopes presented provide valuable information for the development of epitope-based strategies against SARS-CoV-2, such as peptide vaccines and diagnostic tests. Additionally, the updated HLA allelic frequencies provide a better representation of South America and may impact different immunogenetic studies.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Epitopos de Linfócito T/imunologia , Frequência do Gene , Antígenos HLA/genética , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Proteínas do Envelope Viral/imunologia , Alelos , Sequência de Aminoácidos , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Variação Genética , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , América do Sul/epidemiologia , Vacinas de Subunidades/imunologia , Vacinas Virais/imunologia
5.
Front Immunol ; 11: 2130, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013898

RESUMO

In the last decades, a number of infectious viruses have emerged from wildlife or re-emerged, generating serious threats to the global health and to the economy worldwide. Ebola and Marburg hemorrhagic fevers, Lassa fever, Dengue fever, Yellow fever, West Nile fever, Zika, and Chikungunya vector-borne diseases, Swine flu, Severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and the recent Coronavirus disease 2019 (COVID-19) are examples of zoonoses that have spread throughout the globe with such a significant impact on public health that the scientific community has been called for a rapid intervention in preventing and treating emerging infections. Vaccination is probably the most effective tool in helping the immune system to activate protective responses against pathogens, reducing morbidity and mortality, as proven by historical records. Under health emergency conditions, new and alternative approaches in vaccine design and development are imperative for a rapid and massive vaccination coverage, to manage a disease outbreak and curtail the epidemic spread. This review gives an update on the current vaccination strategies for some of the emerging/re-emerging viruses, and discusses challenges and hurdles to overcome for developing efficacious vaccines against future pathogens.


Assuntos
Betacoronavirus/imunologia , Doenças Transmissíveis Emergentes/prevenção & controle , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinação , Vacinas Virais/imunologia , Animais , Anticorpos Facilitadores/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Reações Cruzadas/imunologia , Humanos , Imunização Passiva , Pneumonia Viral/terapia , Pneumonia Viral/virologia , Vacinas Atenuadas/imunologia , Vacinas de DNA/imunologia , Vacinas de Produtos Inativados/imunologia , Vacinas de Subunidades/imunologia
8.
Curr Opin HIV AIDS ; 15(6): 351-358, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32969973

RESUMO

PURPOSE OF REVIEW: Coronavirus disease-19 (COVID-19) is a highly transmittable and pathogenic pneumonia-causing disease, which is caused by severe acute respiratory syndrome coronavirus-2, resulting in millions of deaths globally. Severe acute respiratory syndrome coronavirus-2 may coexist with human populations for a long time. Therefore, high-effective COVID-19 vaccines are an urgent need. RECENT FINDINGS: Vaccines help in the development of long-lasting humoral or cellular immunity, or both, by exposing individuals to antigens that induce an immunological response and memory prior to infections with live pathogens. New vaccine technologies, such as viral vectors and nucleic acid-based vaccines, which represent highly versatile technologies, may allow for faster vaccine manufacture and scale up production. SUMMARY: We summarized the recent progress made in relation to COVID-19 vaccine development using several promising technologies, with particular emphasis on advancements that are currently at the clinical trial stage.


Assuntos
Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Adenoviridae/genética , Infecções por Coronavirus/imunologia , Humanos , Vacinação , Vacinas Atenuadas/imunologia , Vacinas de DNA/imunologia , Vacinas de Produtos Inativados/imunologia , Vacinas Sintéticas/imunologia
9.
Curr Opin HIV AIDS ; 15(6): 328-335, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32969975

RESUMO

PURPOSE OF REVIEW: The Coronavirus Disease 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global health threat associated with major socioeconomic disruptions. Understanding on the transmission characteristics of SARS-CoV-2 is crucial for optimizing preventive strategies. RECENT FINDINGS: SARS-CoV-2 can be transmitted efficiently between persons through respiratory droplets and direct and indirect contact. The significance of airborne droplet nuclei in SARS-CoV-2 transmission in the community setting is less clear. SARS-CoV-2 RNA and live viral particles may also be detected in other bodily fluids. Outbreaks have been reported in families, nursing homes, markets, restaurants, churches, shipping vessels, gyms, and healthcare facilities. Nonpharmaceutical preventive measures at both the community and individual levels are essential for reducing the transmission of SARS-CoV-2. SUMMARY: Because well tolerated and effective vaccines for SARS-CoV-2 are unlikely to be widely available in the near future, there is an urgent need for finding other measures to reduce the spread of the COVID-19 pandemic. With better understanding of its transmission characteristics, practical nonpharmaceutical preventive measures remain essential to reduce SARS-CoV-2 transmission and its associated health and socioeconomic burdens.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Infecções por Coronavirus/imunologia , Humanos , Vacinas Virais/imunologia
11.
Emerg Microbes Infect ; 9(1): 2076-2090, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32897177

RESUMO

The current coronavirus disease 2019 (COVID-19) pandemic was the result of the rapid transmission of a highly pathogenic coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), for which there is no efficacious vaccine or therapeutic. Toward the development of a vaccine, here we expressed and evaluated as potential candidates four versions of the spike (S) protein using an insect cell expression system: receptor binding domain (RBD), S1 subunit, the wild-type S ectodomain (S-WT), and the prefusion trimer-stabilized form (S-2P). We showed that RBD appears as a monomer in solution, whereas S1, S-WT, and S-2P associate as homotrimers with substantial glycosylation. Cryo-electron microscopy analyses suggested that S-2P assumes an identical trimer conformation as the similarly engineered S protein expressed in 293 mammalian cells but with reduced glycosylation. Overall, the four proteins confer excellent antigenicity with convalescent COVID-19 patient sera in enzyme-linked immunosorbent assay (ELISA), yet show distinct reactivities in immunoblotting. RBD, S-WT and S-2P, but not S1, induce high neutralization titres (>3-log) in mice after a three-round immunization regimen. The high immunogenicity of S-2P could be maintained at the lowest dose (1 µg) with the inclusion of an aluminium adjuvant. Higher doses (20 µg) of S-2P can elicit high neutralization titres in non-human primates that exceed 40-times the mean titres measured in convalescent COVID-19 subjects. Our results suggest that the prefusion trimer-stabilized SARS-CoV-2 S-protein from insect cells may offer a potential candidate strategy for the development of a recombinant COVID-19 vaccine.


Assuntos
Antígenos Virais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Imunogenicidade da Vacina/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Linhagem Celular , Infecções por Coronavirus/imunologia , Microscopia Crioeletrônica , Ensaio de Imunoadsorção Enzimática , Humanos , Macaca fascicularis , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Peptidil Dipeptidase A/metabolismo , Domínios Proteicos/genética , Domínios Proteicos/imunologia , Células Sf9 , Glicoproteína da Espícula de Coronavírus/genética , Spodoptera , Vacinação , Proteínas do Envelope Viral/imunologia
12.
J Immunol Res ; 2020: 2837670, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32964056

RESUMO

The novel coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has previously never been identified with humans, thereby creating devastation in public health. The need for an effective vaccine to curb this pandemic cannot be overemphasized. In view of this, we designed a subcomponent antigenic peptide vaccine targeting the N-terminal (NT) and C-terminal (CT) RNA binding domains of the nucleocapsid protein that aid in viral replication. Promising antigenic B cell and T cell epitopes were predicted using computational pipelines. The peptides "RIRGGDGKMKDL" and "AFGRRGPEQTQGNFG" were the B cell linear epitopes with good antigenic index and nonallergenic property. Two CD8+ and Three CD4+ T cell epitopes were also selected considering their safe immunogenic profiling such as allergenicity, antigen level conservancy, antigenicity, peptide toxicity, and putative restrictions to a number of MHC-I and MHC-II alleles. With these selected epitopes, a nonallergenic chimeric peptide vaccine incapable of inducing a type II hypersensitivity reaction was constructed. The molecular interaction between the Toll-like receptor-5 (TLR5) which was triggered by the vaccine was analyzed by molecular docking and scrutinized using dynamics simulation. Finally, in silico cloning was performed to ensure the expression and translation efficiency of the vaccine, utilizing the pET-28a vector. This research, therefore, provides a guide for experimental investigation and validation.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Proteínas do Nucleocapsídeo/imunologia , Nucleocapsídeo/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteínas do Nucleocapsídeo/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/imunologia , Motivos de Ligação ao RNA/imunologia , Receptor 5 Toll-Like/metabolismo , Vacinas Atenuadas/imunologia , Vacinas de Subunidades/imunologia
13.
Sci Rep ; 10(1): 15643, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973171

RESUMO

As the SARS-CoV-2 pandemic is rapidly progressing, the need for the development of an effective vaccine is critical. A promising approach for vaccine development is to generate, through codon pair deoptimization, an attenuated virus. This approach carries the advantage that it only requires limited knowledge specific to the virus in question, other than its genome sequence. Therefore, it is well suited for emerging viruses, for which we may not have extensive data. We performed comprehensive in silico analyses of several features of SARS-CoV-2 genomic sequence (e.g., codon usage, codon pair usage, dinucleotide/junction dinucleotide usage, RNA structure around the frameshift region) in comparison with other members of the coronaviridae family of viruses, the overall human genome, and the transcriptome of specific human tissues such as lung, which are primarily targeted by the virus. Our analysis identified the spike (S) and nucleocapsid (N) proteins as promising targets for deoptimization and suggests a roadmap for SARS-CoV-2 vaccine development, which can be generalizable to other viruses.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/prevenção & controle , Proteínas do Nucleocapsídeo/genética , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Virais/imunologia , Sequência de Bases , Infecções por Coronavirus/imunologia , Genoma Viral/genética , Humanos , Proteínas do Nucleocapsídeo/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de Produtos Inativados/imunologia , Sequenciamento Completo do Genoma
14.
Nat Rev Immunol ; 20(10): 615-632, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32887954

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the most formidable challenge to humanity in a century. It is widely believed that prepandemic normalcy will never return until a safe and effective vaccine strategy becomes available and a global vaccination programme is implemented successfully. Here, we discuss the immunological principles that need to be taken into consideration in the development of COVID-19 vaccine strategies. On the basis of these principles, we examine the current COVID-19 vaccine candidates, their strengths and potential shortfalls, and make inferences about their chances of success. Finally, we discuss the scientific and practical challenges that will be faced in the process of developing a successful vaccine and the ways in which COVID-19 vaccine strategies may evolve over the next few years.


Assuntos
Anticorpos Antivirais/biossíntese , Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Vacinas Virais/imunologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Ensaios Clínicos como Assunto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Vetores Genéticos/química , Vetores Genéticos/imunologia , Humanos , Imunidade Coletiva/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Esquemas de Imunização , Imunogenicidade da Vacina , Segurança do Paciente , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/virologia , Vacinas Atenuadas , Vacinas de DNA , Vacinas de Subunidades , Vacinas de Partículas Semelhantes a Vírus , Vacinas Virais/administração & dosagem , Vacinas Virais/biossíntese
16.
Indian J Pediatr ; 87(10): 810-816, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32880819

RESUMO

The pandemic declaration of Covid-19 disease by World Health Organization (WHO) and subsequent widespread morbidities and mortalities in almost all countries of the world led to the research and development to find out a vaccine against SARS-CoV2 virus. Normally any new vaccine development takes 10-15 y time but the search for vaccine against SARS-CoV2 is going on at a very fast pace resulting in almost breakthrough in vaccine development by several research institutions and vaccine manufacturers. In pandemic situation, however, the entire process of vaccine development including clinical trials gets shortened and may be fast tracked to 15-18 mo time. It is expected that there shall be simultaneous marketing of several vaccines by the beginning of 2021. There are more than 164 candidate vaccines which are in the process of development and among them 24 vaccines are in advanced stages of development. This review aims at highlighting the present stages of development of vaccines and discussing the challenges that may be faced with these novel vaccines.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Pesquisa Biomédica , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Desenvolvimento de Medicamentos , Humanos , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Vacinas , Vacinas Virais/química , Organização Mundial da Saúde
17.
Vaccine ; 38(45): 7049-7056, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32980199

RESUMO

BACKGROUND: Maintaining health of healthcare workers with vaccination is a major component of pandemic preparedness and acceptance of vaccinations is essential to its success. This study aimed to examine impact of the coronavirus disease 2019 (COVID-19) pandemic on change of influenza vaccination acceptance and identify factors associated with acceptance of potential COVID-19 vaccination. METHOD: A cross-sectional self-administered anonymous questionnaire survey was conducted among nurses in Hong Kong, China during 26 February and 31 March 2020. Their previous acceptance of influenza vaccination and intentions to accept influenza and COVID-19 vaccination were collected. Their relationship with work-related and other factors were examined using multiple multinomial logistic regressions. RESULTS: Responses from 806 participants were retrieved. More nurses changed from vaccination refusal to hesitancy or acceptance than those changed from acceptance to vaccination hesitancy or refusal (15.5% vs 6.8% among all participants, P < 0.001). 40.0% participants intended to accept COVID-19 vaccination, and those in private sector (OR: 1.67, 95%CI: 1.11-2.51), with chronic conditions (OR: 1.83, 95%CI: 1.22-2.77), encountering with suspected or confirmed COVID-19 patients (OR: 1.63, 95%CI: 1.14-2.33), accepted influenza vaccination in 2019 (OR: 2.03, 95%CI: 1.47-2.81) had higher intentions to accept it. Reasons for refusal and hesitation for COVID-19 vaccination included "suspicion on efficacy, effectiveness and safety", "believing it unnecessary", and "no time to take it". CONCLUSION: With a low level of COVID-19 acceptance intentions and high proportion of hesitation in both influenza and COVID-19 vaccination, evidence-based planning are needed to improve the uptake of both vaccinations in advance of their implementation. Future studies are needed to explore reasons of change of influenza vaccination acceptance, look for actual behaviour patterns of COVID-19 vaccination acceptance and examine effectiveness of promotion strategies.


Assuntos
Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/psicologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/psicologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/psicologia , Vacinação/psicologia , Adolescente , Adulto , Fatores Etários , Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Estudos Transversais , Feminino , Pessoal de Saúde , Hong Kong/epidemiologia , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Intenção , Masculino , Pessoa de Meia-Idade , Orthomyxoviridae/patogenicidade , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Segurança do Paciente , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Fatores Sexuais , Inquéritos e Questionários , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia
18.
Lancet ; 396(10255): 887-897, 2020 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-32896291

RESUMO

BACKGROUND: We developed a heterologous COVID-19 vaccine consisting of two components, a recombinant adenovirus type 26 (rAd26) vector and a recombinant adenovirus type 5 (rAd5) vector, both carrying the gene for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein (rAd26-S and rAd5-S). We aimed to assess the safety and immunogenicity of two formulations (frozen and lyophilised) of this vaccine. METHODS: We did two open, non-randomised phase 1/2 studies at two hospitals in Russia. We enrolled healthy adult volunteers (men and women) aged 18-60 years to both studies. In phase 1 of each study, we administered intramuscularly on day 0 either one dose of rAd26-S or one dose of rAd5-S and assessed the safety of the two components for 28 days. In phase 2 of the study, which began no earlier than 5 days after phase 1 vaccination, we administered intramuscularly a prime-boost vaccination, with rAd26-S given on day 0 and rAd5-S on day 21. Primary outcome measures were antigen-specific humoral immunity (SARS-CoV-2-specific antibodies measured by ELISA on days 0, 14, 21, 28, and 42) and safety (number of participants with adverse events monitored throughout the study). Secondary outcome measures were antigen-specific cellular immunity (T-cell responses and interferon-γ concentration) and change in neutralising antibodies (detected with a SARS-CoV-2 neutralisation assay). These trials are registered with ClinicalTrials.gov, NCT04436471 and NCT04437875. FINDINGS: Between June 18 and Aug 3, 2020, we enrolled 76 participants to the two studies (38 in each study). In each study, nine volunteers received rAd26-S in phase 1, nine received rAd5-S in phase 1, and 20 received rAd26-S and rAd5-S in phase 2. Both vaccine formulations were safe and well tolerated. The most common adverse events were pain at injection site (44 [58%]), hyperthermia (38 [50%]), headache (32 [42%]), asthenia (21 [28%]), and muscle and joint pain (18 [24%]). Most adverse events were mild and no serious adverse events were detected. All participants produced antibodies to SARS-CoV-2 glycoprotein. At day 42, receptor binding domain-specific IgG titres were 14 703 with the frozen formulation and 11 143 with the lyophilised formulation, and neutralising antibodies were 49·25 with the frozen formulation and 45·95 with the lyophilised formulation, with a seroconversion rate of 100%. Cell-mediated responses were detected in all participants at day 28, with median cell proliferation of 2·5% CD4+ and 1·3% CD8+ with the frozen formulation, and a median cell proliferation of 1·3% CD4+ and 1·1% CD8+ with the lyophilised formulation. INTERPRETATION: The heterologous rAd26 and rAd5 vector-based COVID-19 vaccine has a good safety profile and induced strong humoral and cellular immune responses in participants. Further investigation is needed of the effectiveness of this vaccine for prevention of COVID-19. FUNDING: Ministry of Health of the Russian Federation.


Assuntos
Infecções por Coronavirus/prevenção & controle , Imunização Secundária , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Adenoviridae , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G/sangue , Injeções Intramusculares , Masculino , Federação Russa , Vacinas Virais/efeitos adversos , Adulto Jovem
19.
Infect Dis Poverty ; 9(1): 132, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938504

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) linked with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause severe illness and life-threatening pneumonia in humans. The current COVID-19 pandemic demands an effective vaccine to acquire protection against the infection. Therefore, the present study was aimed to design a multiepitope-based subunit vaccine (MESV) against COVID-19. METHODS: Structural proteins (Surface glycoprotein, Envelope protein, and Membrane glycoprotein) of SARS-CoV-2 are responsible for its prime functions. Sequences of proteins were downloaded from GenBank and several immunoinformatics coupled with computational approaches were employed to forecast B- and T- cell epitopes from the SARS-CoV-2 highly antigenic structural proteins to design an effective MESV. RESULTS: Predicted epitopes suggested high antigenicity, conserveness, substantial interactions with the human leukocyte antigen (HLA) binding alleles, and collective global population coverage of 88.40%. Taken together, 276 amino acids long MESV was designed by connecting 3 cytotoxic T lymphocytes (CTL), 6 helper T lymphocyte (HTL) and 4 B-cell epitopes with suitable adjuvant and linkers. The MESV construct was non-allergenic, stable, and highly antigenic. Molecular docking showed a stable and high binding affinity of MESV with human pathogenic toll-like receptors-3 (TLR3). Furthermore, in silico immune simulation revealed significant immunogenic response of MESV. Finally, MEV codons were optimized for its in silico cloning into the Escherichia coli K-12 system, to ensure its increased expression. CONCLUSION: The MESV developed in this study is capable of generating immune response against COVID-19. Therefore, if designed MESV further investigated experimentally, it would be an effective vaccine candidate against SARS-CoV-2 to control and prevent COVID-19.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Epitopos de Linfócito T/química , Epitopos de Linfócito T/genética , Humanos , Imunogenicidade da Vacina/imunologia , Simulação de Acoplamento Molecular , Pneumonia Viral/imunologia , Análise de Sequência de Proteína , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Receptor 3 Toll-Like/química , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/imunologia , Vacinas de Subunidades/química , Vacinas de Subunidades/genética , Vacinas de Subunidades/imunologia , Vacinologia/métodos , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/imunologia , Vacinas Virais/química , Vacinas Virais/genética
20.
Nat Microbiol ; 5(10): 1185-1191, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32908214

RESUMO

Antibody-based drugs and vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are being expedited through preclinical and clinical development. Data from the study of SARS-CoV and other respiratory viruses suggest that anti-SARS-CoV-2 antibodies could exacerbate COVID-19 through antibody-dependent enhancement (ADE). Previous respiratory syncytial virus and dengue virus vaccine studies revealed human clinical safety risks related to ADE, resulting in failed vaccine trials. Here, we describe key ADE mechanisms and discuss mitigation strategies for SARS-CoV-2 vaccines and therapies in development. We also outline recently published data to evaluate the risks and opportunities for antibody-based protection against SARS-CoV-2.


Assuntos
Anticorpos Facilitadores , Betacoronavirus , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , Vacinas Virais/efeitos adversos , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Humanos , Imunização Passiva/efeitos adversos , Técnicas In Vitro , Modelos Imunológicos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Doenças Respiratórias/etiologia , Doenças Respiratórias/imunologia , Fatores de Risco , Segurança , Vacinas Virais/imunologia
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