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Abera A, Tegally H, Tasew G, Wilkinson E, Ali A, Regasa F, Bitew M, Chabuka L, Mwanyika G, Tshiabuila D, Giandhari J, Pillay S, Poogavanan J, Moir M, Kraemer MUG, Khan K, Huber C, Tollera G, de Wit TFR, Baxter C, Lessells R, Wolday D, Beyene D, de Oliveira T. Genomic characterization of Dengue virus circulation in Ethiopia. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.07.10.24310195. [PMID: 39040196 PMCID: PMC11261913 DOI: 10.1101/2024.07.10.24310195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
In Ethiopia, dengue virus (DENV) infections have been reported in several regions, however, little is known about the circulating genetic diversity. Here, we conducted clinical surveillance for DENV during the 2023 nationwide outbreak and sequenced DENV whole genomes for the first time in Ethiopia. We enrolled patients at three sentinel hospital sites. Using RT-PCR, we screened serum samples for three arboviruses followed by serotyping and sequencing for DENV-positive samples (10.4% of samples). We detected two DENV serotypes (DENV1 and DENV3). Phylogenetic analysis identified one transmission cluster of DENV1 (genotype III major lineage A), and two clusters of DENV3 (genotype III major lineage B). The first showed close evolutionary relationship to the 2023 Italian outbreak and the second cluster to Indian isolates. Co-circulation of DENV1 and DENV3 in some regions of Ethiopia highlights the potential for severe dengue. Intensified surveillance and coordinated public health response are needed to address the threat of severe dengue outbreaks.
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Bigay J, Le Grand R, Martinon F, Maisonnasse P. Vaccine-associated enhanced disease in humans and animal models: Lessons and challenges for vaccine development. Front Microbiol 2022; 13:932408. [PMID: 36033843 PMCID: PMC9399815 DOI: 10.3389/fmicb.2022.932408] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/19/2022] [Indexed: 11/13/2022] Open
Abstract
The fight against infectious diseases calls for the development of safe and effective vaccines that generate long-lasting protective immunity. In a few situations, vaccine-mediated immune responses may have led to exacerbated pathology upon subsequent infection with the pathogen targeted by the vaccine. Such vaccine-associated enhanced disease (VAED) has been reported, or at least suspected, in animal models, and in a few instances in humans, for vaccine candidates against the respiratory syncytial virus (RSV), measles virus (MV), dengue virus (DENV), HIV-1, simian immunodeficiency virus (SIV), feline immunodeficiency virus (FIV), severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1), and the Middle East respiratory syndrome coronavirus (MERS-CoV). Although alleviated by clinical and epidemiological evidence, a number of concerns were also initially raised concerning the short- and long-term safety of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is causing the ongoing COVID-19 pandemic. Although the mechanisms leading to this phenomenon are not yet completely understood, the individual and/or collective role of antibody-dependent enhancement (ADE), complement-dependent enhancement, and cell-dependent enhancement have been highlighted. Here, we review mechanisms that may be associated with the risk of VAED, which are important to take into consideration, both in the assessment of vaccine safety and in finding ways to define models and immunization strategies that can alleviate such concerns.
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Affiliation(s)
| | | | - Frédéric Martinon
- Immunology of Viral Infections and Autoimmune Diseases (IMVA), IDMIT Department, Institut de Biologie François-Jacob (IBJF), University Paris-Sud-INSERM U1184, CEA, Fontenay-Aux-Roses, France
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Alves AMB, Costa SM, Pinto PBA. Dengue Virus and Vaccines: How Can DNA Immunization Contribute to This Challenge? FRONTIERS IN MEDICAL TECHNOLOGY 2021; 3:640964. [PMID: 35047911 PMCID: PMC8757892 DOI: 10.3389/fmedt.2021.640964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 03/17/2021] [Indexed: 01/02/2023] Open
Abstract
Dengue infections still have a tremendous impact on public health systems in most countries in tropical and subtropical regions. The disease is systemic and dynamic with broad range of manifestations, varying from mild symptoms to severe dengue (Dengue Hemorrhagic Fever and Dengue Shock Syndrome). The only licensed tetravalent dengue vaccine, Dengvaxia, is a chimeric yellow fever virus with prM and E genes from the different dengue serotypes. However, recent results indicated that seronegative individuals became more susceptible to develop severe dengue when infected after vaccination, and now WHO recommends vaccination only to dengue seropositive people. One possibility to explain these data is the lack of robust T-cell responses and antibody-dependent enhancement of virus replication in vaccinated people. On the other hand, DNA vaccines are excellent inducers of T-cell responses in experimental animals and it can also elicit antibody production. Clinical trials with DNA vaccines have improved and shown promising results regarding the use of this approach for human vaccination. Therefore, in this paper we review preclinical and clinical tests with DNA vaccines against the dengue virus. Most of the studies are based on the E protein since this antigen is the main target for neutralizing antibody production. Yet, there are other reports with DNA vaccines based on non-structural dengue proteins with protective results, as well. Combining structural and non-structural genes may be a solution for inducing immune responses aging in different infection moments. Furthermore, DNA immunizations are also a very good approach in combining strategies for vaccines against dengue, in heterologous prime/boost regimen or even administering different vaccines at the same time, in order to induce efficient humoral and cellular immune responses.
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Affiliation(s)
- Ada Maria Barcelos Alves
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
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Rodrigues-Alves ML, Melo-Júnior OADO, Silveira P, Mariano RMDS, Leite JC, Santos TAP, Soares IS, Lair DF, Melo MM, Resende LA, da Silveira-Lemos D, Dutra WO, Gontijo NDF, Araujo RN, Sant'Anna MRV, Andrade LAF, da Fonseca FG, Moreira LA, Giunchetti RC. Historical Perspective and Biotechnological Trends to Block Arboviruses Transmission by Controlling Aedes aegypti Mosquitos Using Different Approaches. Front Med (Lausanne) 2020; 7:275. [PMID: 32656216 PMCID: PMC7325419 DOI: 10.3389/fmed.2020.00275] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 05/18/2020] [Indexed: 12/30/2022] Open
Abstract
Continuous climate changes associated with the disorderly occupation of urban areas have exposed Latin American populations to the emergence and reemergence of arboviruses transmitted by Aedes aegypti. The magnitude of the financial and political problems these epidemics may bring to the future of developing countries is still ignored. Due to the lack of effective antiviral drugs and vaccines against arboviruses, the primary measure for preventing or reducing the transmission of diseases depends entirely on the control of vectors or the interruption of human-vector contact. In Brazil the first attempt to control A. aegypti took place in 1902 by eliminating artificial sites of eproduction. Other strategies, such as the use of oviposition traps and chemical control with dichlorodiphenyltrichlorethane and pyrethroids, were successful, but only for a limited time. More recently, biotechnical approaches, such as the release of transgenics or sterile mosquitoes and the, development of transmission blocking vaccines, are being applied to try to control the A. aegypti population and/or arbovirus transmission. Endemic countries spend about twice as much to treat patients as they do on the prevention of mosquito-transmitted diseases. The result of this strategy is an explosive outbreak of arboviruses cases. This review summarizes the social impacts caused by A. aegypti-transmitted diseases, mainly from a biotechnological perspective in vector control aimed at protecting Latin American populations against arboviruses.
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Affiliation(s)
- Marina Luiza Rodrigues-Alves
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Otoni Alves de Oliveira Melo-Júnior
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Patrícia Silveira
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Reysla Maria da Silveira Mariano
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Jaqueline Costa Leite
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Thaiza Aline Pereira Santos
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Ingrid Santos Soares
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Daniel Ferreira Lair
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Marília Martins Melo
- Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Lucilene Aparecida Resende
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Denise da Silveira-Lemos
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
- Departamento de Medicina, Universidade José Do Rosário Vellano, UNIFENAS, Belo Horizonte, Brazil
| | - Walderez Ornelas Dutra
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Nelder de Figueiredo Gontijo
- Laboratório de Fisiologia de Insetos Hematófagos, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Ricardo Nascimento Araujo
- Laboratório de Fisiologia de Insetos Hematófagos, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Mauricio Roberto Viana Sant'Anna
- Laboratório de Fisiologia de Insetos Hematófagos, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Luis Adan Flores Andrade
- Laboratório de Virologia Básica e Aplicada, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Flávio Guimarães da Fonseca
- Laboratório de Virologia Básica e Aplicada, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Luciano Andrade Moreira
- Laboratório de Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou, Fiocruz, Belo Horizonte, Brazil
| | - Rodolfo Cordeiro Giunchetti
- Laboratório de Biologia das Interações Celulares, Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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Halstead SB, Dans LF. Dengue infection and advances in dengue vaccines for children. THE LANCET CHILD & ADOLESCENT HEALTH 2019; 3:734-741. [PMID: 31378686 DOI: 10.1016/s2352-4642(19)30205-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/23/2019] [Accepted: 06/10/2019] [Indexed: 12/26/2022]
Abstract
Dengue viruses are endemic in most tropical and subtropical countries where they produce disease ranging from a mild fever to a severe, potentially fatal vascular permeability syndrome. We reviewed the status of development and testing in children of three vaccines designed to protect against the four dengue viruses. The first dengue virus vaccine, Dengvaxia, now licensed in 20 endemic countries, the EU and the USA, provides protection against severe dengue in seropositive individuals but increases the risk for naive recipients to develop severe dengue and to be hospitalised. We discuss mechanisms and implications of shortcomings of the licensed vaccine and describe the structure and attributes of two other dengue virus vaccines. Based upon human dengue challenge studies, one of these vaccines promises to deliver solid, long-lasting immunity after a single dose. Because dengue virus infections are ubiquitous in residents and visitors to tropical countries, in the absence of a protective vaccine paediatricians should recognise the early signs and clinical presentation of severe dengue, understand its pathophysiology and appropriate management.
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Affiliation(s)
- Scott B Halstead
- Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
| | - Leonila F Dans
- Departments of Pediatrics and Clinical Epidemiology, College of Medicine, University of the Philippines, Manila, Philippines
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Abstract
This is a selective review of recent publications on dengue clinical features, epidemiology, pathogenesis, and vaccine development placed in a context of observations made over the past half century. Four dengue viruses (DENVs) are transmitted by urban cycle mosquitoes causing diseases whose nature and severity are influenced by interacting factors such as virus, age, immune status of the host, and human genetic variability. A phenomenon that controls the kinetics of DENV infection, antibody-dependent enhancement, best explains the correlation of the vascular permeability syndrome with second heterotypic DENV infections and infection in the presence of passively acquired antibodies. Based on growing evidence in vivo and in vitro, the tissue-damaging DENV non-structural protein 1 (NS1) is responsible for most of the pathophysiological features of severe dengue. This review considers the contribution of hemophagocytic histiocytosis syndrome to cases of severe dengue, the role of movement of humans in dengue epidemiology, and modeling and planning control programs and describes a country-wide survey for dengue infections in Bangladesh and efforts to learn what controls the clinical outcome of dengue infections. Progress and problems with three tetravalent live-attenuated vaccines are reviewed. Several research mysteries remain: why is the risk of severe disease during second heterotypic DENV infection so low, why is the onset of vascular permeability correlated with defervescence, and what are the crucial components of protective immunity?
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Affiliation(s)
- Scott Halstead
- Emeritus Professor, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
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Verma M, Bhatnagar S, Kumari K, Mittal N, Sukhralia S, Gopirajan At S, Dhanaraj PS, Lal R. Highly conserved epitopes of DENV structural and non-structural proteins: Candidates for universal vaccine targets. Gene 2019; 695:18-25. [PMID: 30738967 PMCID: PMC7125761 DOI: 10.1016/j.gene.2019.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 01/22/2019] [Accepted: 02/01/2019] [Indexed: 12/11/2022]
Abstract
Dengue is a severe emerging arthropod borne viral disease occurring globally. Around two fifths of the world's population, or up to 3.9 billion people, are at a risk of dengue infection. Infection induces a life-long protective immunity to the homologous serotype but confers only partial and transient protection against subsequent infection caused by other serotypes. Thus, there is a need for a vaccine which is capable of providing a life- long protection against all the serotypes of dengue virus. In our study, comparative genomics of Dengue virus (DENV) was conducted to explore potential candidates for novel vaccine targets. From our analysis we successfully found 100% conserved epitopes in Envelope protein (RCPTQGE); NS3 (SAAQRRGR, PGTSGSPI); NS4A (QRTPQDNQL); NS4B (LQAKATREAQKRA) and NS5 proteins (QRGSGQV) in all DENV serotypes. Some serotype specific conserved motifs were also found in NS1, NS5, Capsid, PrM and Envelope proteins. Using comparative genomics and immunoinformatics approach, we could find conserved epitopes which can be explored as peptide vaccine candidates to combat dengue worldwide. Serotype specific epitopes can also be exploited for rapid diagnostics. All ten proteins are explored to find the conserved epitopes in DENV serotypes, thus making it the most extensively studied viral genome so far.
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Affiliation(s)
- Mansi Verma
- Sri Venkateswara College, South Campus, University of Delhi, New Delhi 110021, India; Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi 110007, India.
| | - Shradha Bhatnagar
- Sri Venkateswara College, South Campus, University of Delhi, New Delhi 110021, India
| | - Kavita Kumari
- Sri Venkateswara College, South Campus, University of Delhi, New Delhi 110021, India
| | - Nidhi Mittal
- Sri Venkateswara College, South Campus, University of Delhi, New Delhi 110021, India
| | - Shivani Sukhralia
- Sri Venkateswara College, South Campus, University of Delhi, New Delhi 110021, India
| | - Shruthi Gopirajan At
- Sri Venkateswara College, South Campus, University of Delhi, New Delhi 110021, India
| | - P S Dhanaraj
- Sri Venkateswara College, South Campus, University of Delhi, New Delhi 110021, India
| | - Rup Lal
- Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi 110007, India
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Nguyen LH, Tran BX, Do CD, Hoang CL, Nguyen TP, Dang TT, Thu Vu G, Tran TT, Latkin CA, Ho CS, Ho RC. Feasibility and willingness to pay for dengue vaccine in the threat of dengue fever outbreaks in Vietnam. Patient Prefer Adherence 2018; 12:1917-1926. [PMID: 30288032 PMCID: PMC6163003 DOI: 10.2147/ppa.s178444] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The escalation of dengue fever (DF) cases in recent years and the occurrence of a large-scale DF outbreak in 2017 underline the importance of dengue vaccines in Vietnam. Given the potential benefits of the dengue vaccines and the need for copayment by the private sector, this study aims to evaluate the willingness to pay (WTP) for the dengue vaccines in patients with DF in Northern Vietnam. METHODS A cross-sectional study was conducted on 330 in-and-out patients with DF admitted to the Bach Mai Hospital. We used the contingent valuation method to evaluate the WTP for dengue vaccines. Socioeconomic and clinical characteristics were also investigated. Multivariate interval and logistic regression models were used to estimate the average amount of WTP and identify the factors associated with the WTP. RESULTS Around 77.3% patients were willing to pay an average amount of US$ 67.4 (95% CI=57.4-77.4) for the vaccine. People of higher ages, those having health insurance, those traveling in the past 15 days or suffering from anxiety/depression were less likely to be willing to pay for the dengue vaccine. However, people having a longer duration of DF or having problems with mobility were positively associated with WTP for the dengue vaccine. Patients educated to more than high school levels (Coeff.=31.31; 95% CI=3.26-59.35), those in the richest quintile (Coeff.=62.76; 95% CI=25.40; 100.13), or those having a longer duration of the disease (Coeff.=6.18; 95% CI=0.72-11.63) were willing to pay a higher amount. CONCLUSION This study highlights a relatively high rate and amount of WTP for the dengue vaccine among patients with DF. Psychological counseling services as well as educational campaigns should be undertaken to improve the WTP for the vaccine. Moreover, government subsidies should be given to increase the coverage of the vaccine in the future, especially for the poor.
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Affiliation(s)
- Long Hoang Nguyen
- Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden
| | - Bach Xuan Tran
- Institute for Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam,
- Department of Health, Behavior, and Society, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA,
- Vietnam Young Physician Association, Hanoi, Vietnam,
| | - Cuong Duy Do
- Department of Infectious Diseases, Bach Mai Hospital, Hanoi, Vietnam
| | - Chi Linh Hoang
- Center of Excellence in Behavioral Medicine, Nguyen Tat Thanh University, Ho Chi Minh city, Vietnam
| | - Thao Phuong Nguyen
- Institute for Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam,
| | - Trang Thi Dang
- Institute for Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam,
| | - Giang Thu Vu
- Institute for Global Health Innovations, Duy Tan University, Da Nang, Vietnam
| | - Tung Thanh Tran
- Institute for Global Health Innovations, Duy Tan University, Da Nang, Vietnam
| | - Carl A Latkin
- Department of Health, Behavior, and Society, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA,
| | - Cyrus S Ho
- Department of Psychological Medicine, National University Hospital, Singapore, Singapore
| | - Roger Cm Ho
- Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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An Envelope-Modified Tetravalent Dengue Virus-Like-Particle Vaccine Has Implications for Flavivirus Vaccine Design. J Virol 2017; 91:JVI.01181-17. [PMID: 28956764 DOI: 10.1128/jvi.01181-17] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 09/09/2017] [Indexed: 12/30/2022] Open
Abstract
Dengue viruses (DENV) infect 50 to 100 million people each year. The spread of DENV-associated infections is one of the most serious public health problems worldwide, as there is no widely available vaccine or specific therapeutic for DENV infections. To address this, we developed a novel tetravalent dengue vaccine by utilizing virus-like particles (VLPs). We created recombinant DENV1 to -4 (DENV1-4) VLPs by coexpressing precursor membrane (prM) and envelope (E) proteins, with an F108A mutation in the fusion loop structure of E to increase the production of VLPs in mammalian cells. Immunization with DENV1-4 VLPs as individual, monovalent vaccines elicited strong neutralization activity against each DENV serotype in mice. For use as a tetravalent vaccine, DENV1-4 VLPs elicited high levels of neutralization activity against all four serotypes simultaneously. The neutralization antibody responses induced by the VLPs were significantly higher than those with DNA or recombinant E protein immunization. Moreover, antibody-dependent enhancement (ADE) was not observed against any serotype at a 1:10 serum dilution. We also demonstrated that the Zika virus (ZIKV) VLP production level was enhanced by introducing the same F108A mutation into the ZIKV envelope protein. Taken together, these results suggest that our strategy for DENV VLP production is applicable to other flavivirus VLP vaccine development, due to the similarity in viral structures, and they describe the promising development of an effective tetravalent vaccine against the prevalent flavivirus.IMPORTANCE Dengue virus poses one of the most serious public health problems worldwide, and the incidence of diseases caused by the virus has increased dramatically. Despite decades of effort, there is no effective treatment against dengue. A safe and potent vaccine against dengue is still needed. We developed a novel tetravalent dengue vaccine by using virus-like particles (VLPs), which are noninfectious because they lack the viral genome. Previous attempts of other groups to use dengue VLPs resulted in generally poor yields. We found that a critical amino acid mutation in the envelope protein enhances the production of VLPs. Our tetravalent vaccine elicited potent neutralizing antibody responses against all four DENV serotypes. Our findings can also be applied to vaccine development against other flaviviruses, such as Zika virus or West Nile virus.
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Elaboration of tetravalent antibody responses against dengue viruses using a subunit vaccine comprised of a single consensus dengue envelope sequence. Vaccine 2017; 35:6308-6320. [PMID: 28987441 DOI: 10.1016/j.vaccine.2017.09.063] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 09/18/2017] [Accepted: 09/20/2017] [Indexed: 02/01/2023]
Abstract
Dengue viruses (DENVs) are re-emerging pathogens transmitted by mosquitoes mainly in tropical and subtropical regions. Each year, they are estimated to infect 390 million people globally. The major challenge confronting dengue vaccine development is the need to induce balanced, long lasting tetravalent immune responses against four co-circulating virus serotypes (DENV-I, -II, -III, -IV), because primary infection by any one of which may predispose infected individuals to more severe diseases during a heterotypic secondary infection. Another difficulty is to select representative strains in vaccine design to provide cross-protection against most circulating virus strains. In this study, aimed at developing a tetravalent subunit vaccine with a representative single protein, we designed two vaccines (named cE80(D4) and cE80(max)) based on the consensus sequences of the ectodomain of envelope protein of 3127 DENV strains, and then expressed them in the baculovirus expression system. Both vaccines were capable of eliciting specific antibodies against all four DENV serotypes, and the predominant IgG subtype elicited by the two vaccines was IgG1. Moreover, these vaccines activated both type I and type II antigen-specific helper T cells that secreted IFN-γ and IL-4, respectively. This proof-of-concept study has set foundation for further optimization of a single protein-based tetravalent DENV vaccine.
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Godói IP, Santos AS, Reis EA, Lemos LLP, Brandão CMR, Alvares J, Acurcio FA, Godman B, Guerra Júnior AA. Consumer Willingness to Pay for Dengue Vaccine (CYD-TDV, Dengvaxia ®) in Brazil; Implications for Future Pricing Considerations. Front Pharmacol 2017; 8:41. [PMID: 28210223 PMCID: PMC5288336 DOI: 10.3389/fphar.2017.00041] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 01/19/2017] [Indexed: 01/24/2023] Open
Abstract
Introduction and Objective: Dengue virus is a serious global health problem with an estimated 3.97 billion people at risk for infection worldwide. In December 2015, the first vaccine (CYD-TDV) for dengue prevention was approved in Brazil, developed by Sanofi Pasteur. However, given that the vaccine will potentially be paid via the public health system, information is need regarding consumers' willingness to pay for the dengue vaccine in the country as well as discussions related to the possible inclusion of this vaccine into the public health system. This was the objective of this research. Methods: We conducted a cross-sectional study with residents of Greater Belo Horizonte, Minas Gerais, about their willingness to pay for the CYD-TDV vaccine. Results: 507 individuals were interviewed. These were mostly female (62.4%) had completed high school (62.17%), were working (74.4%), had private health insurance (64.5%) and did not have dengue (67.4%). The maximum median value of consumers' willingness to pay for CYD-TDV vaccine is US$33.61 (120.00BRL) for the complete schedule and US$11.20 (40.00BRL) per dose. At the price determined by the Brazil's regulatory chamber of pharmaceutical products market for the commercialization of Dengvaxia® for three doses, only 17% of the population expressed willingness to pay for this vaccine. Conclusion: Brazil is currently one of the largest markets for dengue vaccine and the price established is a key issue. We believe the manufacturer should asses the possibility of lower prices to reach a larger audience among the Brazilian population.
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Affiliation(s)
- Isabella P. Godói
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
- SUS Collaborating Centre for Technology Assessment and Excellence in Health, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - André S. Santos
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Edna A. Reis
- Department of Statistics, Exact Sciences Institute, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Livia L. P. Lemos
- SUS Collaborating Centre for Technology Assessment and Excellence in Health, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
- Programa de Pós-graduação em Saúde Pública, Faculdade de Medicina, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Cristina M. R. Brandão
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Juliana Alvares
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
- SUS Collaborating Centre for Technology Assessment and Excellence in Health, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Francisco A. Acurcio
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
- SUS Collaborating Centre for Technology Assessment and Excellence in Health, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | - Brian Godman
- Strathclyde Institute of Pharmacy and Biomedical Sciences, Strathclyde UniversityGlasgow, UK
- Division of Clinical Pharmaclogy, Karolinska Institutet, Karolinska University HospitalStockholm, Sweden
| | - Augusto A. Guerra Júnior
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
- SUS Collaborating Centre for Technology Assessment and Excellence in Health, Faculdade de Farmácia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
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Godói IP, Lemos LLP, de Araújo VE, Bonoto BC, Godman B, Guerra Júnior AA. CYD-TDV dengue vaccine: systematic review and meta-analysis of efficacy, immunogenicity and safety. J Comp Eff Res 2017; 6:165-180. [PMID: 28084784 DOI: 10.2217/cer-2016-0045] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
INTRODUCTION Dengue virus (DENV) is a serious global health problem. CYD-TDC (Dengvaxia®) was the first vaccine to gain regulatory approval to try and address this problem. AIM Summarize all available evidence on the immunogenicity, efficacy and safety of the CYD-TDV dengue vaccine. METHOD Meta-analysis and systematic review. RESULTS The best and worst immunogenicity results were for DENV4 and DENV1, respectively. Vaccine efficacy of 60% was derived from studies with participants aged 2-16 years old, with DENV4 and DENV2 presenting the best and worst results, respectively. Erythema and swelling were more frequent with CYD-TDV. No differences were detected for systemic adverse events. CONCLUSION CYD-TDV showed moderate efficacy in children and adolescents. From the immunogenicity results in adults, we can expect satisfactory efficacy from vaccination in this population.
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Affiliation(s)
- Isabella Piassi Godói
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, sala 1023, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brazil.,SUS Collaborating Centre for Technology Assessment & Excellence in Health, sala 1042, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brazil
| | - Livia Lovato Pires Lemos
- SUS Collaborating Centre for Technology Assessment & Excellence in Health, sala 1042, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brazil
| | - Vânia Eloisa de Araújo
- Faculdade de Odontologia, Instituto de Ciências Biológicas e da Saúde, Pontifícia Universidade Católica de Minas Gerais, Av. Dom José Gaspar, 500 Coração Eucaristíco, Belo Horizonte, Minas Gerais, CEP 30535-901, Brazil
| | - Braúlio Cesar Bonoto
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, sala 1023, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brazil
| | - Brian Godman
- University of Strathclyde Glasgow, Institute of Pharmacy & Biomedical Sciences, Pharmacoepidemiology, 161 Cathedral Street, Glasgow G4 0RE, UK.,Division of Clinical Pharmacology, Karolinska Institutet, Karolinska University Hospital, SE-141 86, Stockholm, Sweden
| | - Augusto Afonso Guerra Júnior
- Programa de Pós-graduação em Medicamentos e Assistência Farmacêutica, sala 1023, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brazil.,SUS Collaborating Centre for Technology Assessment & Excellence in Health, sala 1042, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627, Campus Pampulha, Belo Horizonte, Minas Gerais, CEP 31270-901, Brazil
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13
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Olivero RM, Hamer DH, MacLeod WB, Benoit CM, Sanchez-Vegas C, Jentes ES, Chen LH, Wilson ME, Marano N, Yanni EA, Ooi WW, Karchmer AW, Kogelman L, Barnett ED. Dengue Virus Seroconversion in Travelers to Dengue-Endemic Areas. Am J Trop Med Hyg 2016; 95:1130-1136. [PMID: 27573631 DOI: 10.4269/ajtmh.16-0159] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 08/01/2016] [Indexed: 01/15/2023] Open
Abstract
We conducted a prospective study to measure dengue virus (DENV) antibody seroconversion in travelers to dengue-endemic areas. Travelers seen in the Boston Area Travel Medicine Network planning to visit dengue-endemic countries for ≥ 2 weeks were enrolled from 2009 to 2010. Pre- and post-travel blood samples and questionnaires were collected. Post-travel sera were tested for anti-DENV IgG by indirect IgG enzyme-linked immunosorbent assay (ELISA) and anti-DENV IgM by capture IgM ELISA. Participants with positive post-travel anti-DENV IgG or IgM were tested for pre-travel anti-DENV IgG and IgM; they were excluded from the seroconversion calculation if either pre-travel anti-DENV IgG or IgM were positive. Paired sera and questionnaires were collected for 62% (589/955) of enrolled travelers. Most participants were 19-64 years of age, female, and white. The most common purposes of travel were tourism and visiting friends and relatives; most trips were to Asia or Africa. Median length of travel was 21 days. DENV antibody seroconversion by either anti-DENV IgM or IgG ELISA was 2.9-6.8%; lower range percent excluded potential false-positive anti-DENV IgG due to receipt of yellow fever or Japanese encephalitis vaccines at enrollment; upper range percent excluded proven false-positive anti-DENV IgM. Eighteen percent of those with seroconversion reported dengue-like symptoms. Seroconversion was documented for travel to Africa as well as countries and regions known to be highly dengue endemic (India, Brazil, southeast Asia). Given widespread risk of dengue, travel medicine counseling should include information on risk of dengue in endemic areas and advice on preventing insect bites and seeking prompt medical attention for febrile illness.
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Affiliation(s)
- Rosemary M Olivero
- Section of Pediatric Infectious Diseases, Boston Medical Center, Boston, Massachusetts
| | - Davidson H Hamer
- Center for Global Health and Development, Boston University School of Public Health (BUSPH), Boston, Massachusetts.,Department of Global Health, Boston University School of Public Health (BUSPH), Boston, Massachusetts.,Section of Infectious Diseases, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - William B MacLeod
- Center for Global Health and Development, Boston University School of Public Health (BUSPH), Boston, Massachusetts.,Department of Global Health, Boston University School of Public Health (BUSPH), Boston, Massachusetts
| | - Christine M Benoit
- Section of Pediatric Infectious Diseases, Boston Medical Center, Boston, Massachusetts
| | | | - Emily S Jentes
- Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Lin H Chen
- Travel Medicine Center, Mount Auburn Hospital, Cambridge, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Mary E Wilson
- Department of Global Health and Population, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
| | - Nina Marano
- Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Emad A Yanni
- Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Winnie W Ooi
- Department of Infectious Disease, Lahey Clinic Medical Center, Burlington, Massachusetts
| | - Adolf W Karchmer
- Harvard Medical School, Boston, Massachusetts.,Division of Infectious Disease, Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | - Laura Kogelman
- Division of Geographic Medicine and Infectious Diseases, Tufts Medical Center, Boston, Massachusetts
| | - Elizabeth D Barnett
- Section of Pediatric Infectious Diseases, Boston Medical Center, Boston, Massachusetts.
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14
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Simmons M, Sun P, Putnak R. Recombinant Dengue 2 Virus NS3 Helicase Protein Enhances Antibody and T-Cell Response of Purified Inactivated Vaccine. PLoS One 2016; 11:e0152811. [PMID: 27035715 PMCID: PMC4818016 DOI: 10.1371/journal.pone.0152811] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/19/2016] [Indexed: 12/04/2022] Open
Abstract
Dengue virus purified inactivated vaccines (PIV) are highly immunogenic and protective over the short term, but may be poor at inducing cell-mediated immune responses and long-term protection. The dengue nonstructural protein 3 (NS3) is considered the main target for T-cell responses during viral infection. The amino (N)-terminal protease and the carboxy (C)-terminal helicase domains of DENV-2 NS3 were expressed in E. coli and analyzed for their immune-potentiating capacity. Mice were immunized with DENV-2 PIV with and without recombinant NS3 protease or NS3 helicase proteins, and NS3 proteins alone on days 0, 14 and 28. The NS3 helicase but not the NS3 protease was effective in inducing T-cell responses quantified by IFN-γ ELISPOT. In addition, markedly increased total IgG antibody titer against virus antigen was seen in mice immunized with the PIV/NS3 helicase combination in the ELISA, as well as increased neutralizing antibody titer measured by the plaque reduction neutralization test. These results indicate the potential immunogenic properties of the NS3 helicase protein and its use in a dengue vaccine formulation.
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Affiliation(s)
- Monika Simmons
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Peifang Sun
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Robert Putnak
- Division of Viral Diseases, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
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15
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Sim S, Hibberd ML. Genomic approaches for understanding dengue: insights from the virus, vector, and host. Genome Biol 2016; 17:38. [PMID: 26931545 PMCID: PMC4774013 DOI: 10.1186/s13059-016-0907-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The incidence and geographic range of dengue have increased dramatically in recent decades. Climate change, rapid urbanization and increased global travel have facilitated the spread of both efficient mosquito vectors and the four dengue virus serotypes between population centers. At the same time, significant advances in genomics approaches have provided insights into host–pathogen interactions, immunogenetics, and viral evolution in both humans and mosquitoes. Here, we review these advances and the innovative treatment and control strategies that they are inspiring.
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Affiliation(s)
- Shuzhen Sim
- Infectious Diseases, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Martin L Hibberd
- Infectious Diseases, Genome Institute of Singapore, Singapore, 138672, Singapore. .,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK.
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16
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Nedjadi T, El-Kafrawy S, Sohrab SS, Desprès P, Damanhouri G, Azhar E. Tackling dengue fever: Current status and challenges. Virol J 2015; 12:212. [PMID: 26645066 PMCID: PMC4673751 DOI: 10.1186/s12985-015-0444-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 12/01/2015] [Indexed: 12/22/2022] Open
Abstract
According to recent statistics, 96 million apparent dengue infections were estimated worldwide in 2010. This figure is by far greater than the WHO prediction which indicates the rapid spread of this disease posing a growing threat to the economy and a major challenge to clinicians and health care services across the globe particularly in the affected areas.This article aims at bringing to light the current epidemiological and clinical status of the dengue fever. The relationship between genetic mutations, single nucleotide polymorphism (SNP) and the pathophysiology of disease progression will be put into perspective. It will also highlight the recent advances in dengue vaccine development.Thus far, a significant progress has been made in unraveling the risk factors and understanding the molecular pathogenesis associated with the disease. However, further insights in molecular features of the disease and the development of animal models will enormously help improving the therapeutic interventions and potentially contribute to finding new preventive measures for population at risk.
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Affiliation(s)
- Taoufik Nedjadi
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
| | - Sherif El-Kafrawy
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
| | - Sayed S Sohrab
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
| | - Philippe Desprès
- UMR PIMIT (I2T team), University of Reunion island, INSERM U1187, CNRS 9192, IRD 249, Technology Platform CYROI, 2 rue Maxime Rivière Saint-Clotilde, La Reunion, 97491, France.
| | - Ghazi Damanhouri
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
| | - Esam Azhar
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
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17
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Preclinical and clinical development of a dengue recombinant subunit vaccine. Vaccine 2015; 33:7126-34. [PMID: 26458804 DOI: 10.1016/j.vaccine.2015.09.101] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 08/22/2015] [Accepted: 09/02/2015] [Indexed: 11/22/2022]
Abstract
This review focuses on a dengue virus (DENV) vaccine candidate based on a recombinant subunit approach which targets the DENV envelope glycoprotein (E). Truncated versions of E consisting of the N-terminal portion of E (DEN-80E) have been expressed recombinantly in the Drosophila S2 expression system and shown to have native-like conformation. Preclinical studies demonstrate that formulations containing tetravalent DEN-80E adjuvanted with ISCOMATRIX™ adjuvant induce high titer virus neutralizing antibodies and IFN-γ producing T cells in flavivirus-naïve non-human primates. The preclinical data further suggest that administration of such formulations on a 0, 1, 6 month schedule may result in higher maximum virus neutralizing antibody titers and better durability of those titers compared to administration on a 0, 1, 2 month schedule. In addition, the virus neutralizing antibody titers induced by adjuvanted tetravalent DEN-80E compare favorably to the titers induced by a tetravalent live virus comparator. Furthermore, DEN-80E was demonstrated to be able to boost virus neutralizing antibody titers in macaques that have had a prior DENV exposure. A monovalent version of the vaccine candidate, DEN1-80E, was formulated with Alhydrogel™ and studied in a proof-of-principle Phase I clinical trial by Hawaii Biotech, Inc. (NCT00936429). The clinical trial results demonstrate that both the 10 μg and 50 μg formulations of DEN1-80E with 1.25 mg of elemental aluminum were immunogenic when administered in a 3-injection series (0, 1, 2 months) to healthy, flavivirus-naïve adults. The vaccine formulations induced DENV-1 neutralizing antibodies in the majority of subjects, although the titers in most subjects were modest and waned over time. Both the 10 μg DEN1-80E and the 50 μg DEN1-80E formulations with Alhydrogel™ were generally well tolerated.
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18
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Fang CY, Chen SJ, Wu HN, Ping YH, Lin CY, Shiuan D, Chen CL, Lee YR, Huang KJ. Honokiol, a Lignan Biphenol Derived from the Magnolia Tree, Inhibits Dengue Virus Type 2 Infection. Viruses 2015; 7:4894-910. [PMID: 26378567 PMCID: PMC4584296 DOI: 10.3390/v7092852] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 08/20/2015] [Accepted: 08/26/2015] [Indexed: 01/20/2023] Open
Abstract
Dengue is the most widespread arbovirus infection and poses a serious health and economic issue in tropical and subtropical countries. Currently no licensed vaccine or compounds can be used to prevent or manage the severity of dengue virus (DENV) infection. Honokiol, a lignan biphenol derived from the Magnolia tree, is commonly used in Eastern medicine. Here we report that honokiol has profound antiviral activity against serotype 2 DENV (DENV-2). In addition to inhibiting the intracellular DENV-2 replicon, honokiol was shown to suppress the replication of DENV-2 in baby hamster kidney (BHK) and human hepatocarcinoma Huh7 cells. At the maximum non-toxic dose of honokiol treatment, the production of infectious DENV particles was reduced >90% in BHK and Huh7 cells. The underlying mechanisms revealed that the expression of DENV-2 nonstructural protein NS1/NS3 and its replicating intermediate, double-strand RNA, was dramatically reduced by honokiol treatment. Honokiol has no effect on the expression of DENV putative receptors, but may interfere with the endocytosis of DENV-2 by abrogating the co-localization of DENV envelope glycoprotein and the early endosomes. These results indicate that honokiol inhibits the replication, viral gene expression, and endocytotic process of DENV-2, making it a promising agent for chemotherapy of DENV infection.
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Affiliation(s)
- Chih-Yeu Fang
- Department of Pathology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan.
| | - Siang-Jyun Chen
- Department of Life Science and Institute of Biotechnology, National Dong Hwa University, Hualien 974,Taiwan.
| | - Huey-Nan Wu
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan.
| | - Yueh-Hsin Ping
- Department and Institute of Pharmacology, School of Medicine, National Yang-Ming University,Taipei 112, Taiwan.
- Institute of Biophotonics, National Yang-Ming University, Taipei 112, Taiwan.
| | - Ching-Yen Lin
- Department of Life Science and Institute of Biotechnology, National Dong Hwa University, Hualien 974,Taiwan.
| | - David Shiuan
- Department of Life Science and Institute of Biotechnology, National Dong Hwa University, Hualien 974,Taiwan.
| | - Chi-Long Chen
- Department of Pathology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan.
- Department of Pathology, Taipei Medical University Hospital, Taipei Medical University,Taipei 110, Taiwan.
| | - Ying-Ray Lee
- Department of Medical Research, Chiayi Christian Hospital, Chiayi 600, Taiwan.
- Department of Nursing, Min-Hwei College of Health Care Management, Tainan 73658, Taiwan.
| | - Kao-Jean Huang
- Department of Life Science and Institute of Biotechnology, National Dong Hwa University, Hualien 974,Taiwan.
- Institute of Biologics, Development Center for Biotechnology, New Taipei City 22180, Taiwan.
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19
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Govindarajan D, Meschino S, Guan L, Clements DE, ter Meulen JH, Casimiro DR, Coller BAG, Bett AJ. Preclinical development of a dengue tetravalent recombinant subunit vaccine: Immunogenicity and protective efficacy in nonhuman primates. Vaccine 2015; 33:4105-16. [DOI: 10.1016/j.vaccine.2015.06.067] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/06/2015] [Accepted: 06/14/2015] [Indexed: 11/27/2022]
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20
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Bruno L, Cortese M, Rappuoli R, Merola M. Lessons from Reverse Vaccinology for viral vaccine design. Curr Opin Virol 2015; 11:89-97. [PMID: 25829256 DOI: 10.1016/j.coviro.2015.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/02/2015] [Accepted: 03/03/2015] [Indexed: 12/17/2022]
Abstract
Although almost 15 years have passed since the birthdate of Reverse Vaccinology (RV), there are very limited applications of this approach to viral vaccines discovery. Undeniably, RV presents a series of advantages as it can virtually identify all potential antigens coded by a genome, irrespective of their abundance, phase of expression and immunogenicity. Additionally, it can be applied to all pathogens, including those that cannot be grown in vitro. In this review we summarize the few examples of RV application to viruses, in particular the Herpesviridae, and report the advantage and limitations of this approach. Next we focus on the novel approaches and additional technologies to vaccine development including structure based approach (Structural Vaccinology [SV]), synthetic biology and some examples of their application in the development of viral vaccines.
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Affiliation(s)
| | - Mirko Cortese
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Germany
| | | | - Marcello Merola
- Novartis Vaccines, Siena, Italy; Department of Biology, University of Naples 'Federico II', Naples, Italy
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van Dodewaard CA, Richards SL. Trends in Dengue Cases Imported into the United States from Pan America 2001-2012. ENVIRONMENTAL HEALTH INSIGHTS 2015; 9:33-40. [PMID: 26766913 PMCID: PMC4706086 DOI: 10.4137/ehi.s32833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 05/07/2023]
Abstract
The objective of this study was to improve risk assessments of travel on dengue (DEN) virus (DENV) distribution. We investigated the exposure risk of US citizens traveling to DEN-endemic Pan American countries. The number of DEN cases reported in 51 Pan American countries from 2001 to 2012 was compared to the population of the same countries. The number of US travelers visiting the Pan American countries was categorized by region, and travel-related DEN infections were analyzed. US residents visiting the Dominican Republic exhibited the highest traveler-related DEN incidence. Brazil showed the most DEN cases in its residents (>1 million reported cases in 2010). The number of DEN cases continues to rise as does international travel and the geographic range of potential DENV vectors. DENV risk assessments may be improved by analyzing the possible routes of entry. Underreporting remains an issue for calculating DENV transmission risk by country and region.
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22
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da Costa VG, Marques-Silva AC, Floriano VG, Moreli ML. Safety, immunogenicity and efficacy of a recombinant tetravalent dengue vaccine: A meta-analysis of randomized trials. Vaccine 2014; 32:4885-92. [DOI: 10.1016/j.vaccine.2014.07.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 06/17/2014] [Accepted: 07/08/2014] [Indexed: 12/30/2022]
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Osorio JE, Velez ID, Thomson C, Lopez L, Jimenez A, Haller AA, Silengo S, Scott J, Boroughs KL, Stovall JL, Luy BE, Arguello J, Beatty ME, Santangelo J, Gordon GS, Huang CYH, Stinchcomb DT. Safety and immunogenicity of a recombinant live attenuated tetravalent dengue vaccine (DENVax) in flavivirus-naive healthy adults in Colombia: a randomised, placebo-controlled, phase 1 study. THE LANCET. INFECTIOUS DISEASES 2014; 14:830-8. [PMID: 25087476 PMCID: PMC4648257 DOI: 10.1016/s1473-3099(14)70811-4] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Dengue virus is the most serious mosquito-borne viral threat to public health and no vaccines or antiviral therapies are approved for dengue fever. The tetravalent DENVax vaccine contains a molecularly characterised live attenuated dengue serotype-2 virus (DENVax-2) and three recombinant vaccine viruses expressing the prM and E structural genes for serotypes 1, 3, and 4 in the DENVax-2 genetic backbone. We aimed to assess the safety and immunogenicity of tetravalent DENVax formulations. METHODS We undertook a randomised, double-blind, phase 1, dose-escalation trial between Oct 11, 2011, and Nov 9, 2011, in the Rionegro, Antioquia, Colombia. The first cohort of participants (aged 18-45 years) were randomly assigned centrally, via block randomisation, to receive a low-dose formulation of DENvax, or placebo, by either subcutaneous or intradermal administration. After a safety assessment, participants were randomly assigned to receive a high-dose DENVax formulation, or placebo, by subcutaneous or intradermal administration. Group assignment was not masked from study pharmacists, but allocation was concealed from participants, nurses, and investigators. Primary endpoints were frequency and severity of injection-site and systemic reactions within 28 days of each vaccination. Secondary endpoints were the immunogenicity of DENVax against all four dengue virus serotypes, and the viraemia due to each of the four vaccine components after immunisation. Analysis was by intention to treat for safety and per protocol for immunogenicity. Because of the small sample size, no detailed comparison of adverse event rates were warranted. The trial is registered with ClinicalTrials.gov, number NCT01224639. FINDINGS We randomly assigned 96 patients to one of the four study groups: 40 participants (42%) received low-dose vaccine and eight participants (8%) received placebo in the low-dose groups; 39 participants (41%) received high-dose vaccine, with nine (9%) participants assigned to receive placebo. Both formulations were well tolerated with mostly mild and transient local or systemic reactions. No clinically meaningful differences were recorded in the overall incidence of local and systemic adverse events between patients in the vaccine and placebo groups; 68 (86%) of 79 participants in the vaccine groups had solicited systemic adverse events compared with 13 (76%) of 17 of those in the placebo groups. By contrast, 67 participants (85%) in the vaccine group had local solicited reactions compared with five (29%) participants in the placebo group. Immunisation with either high-dose or low-dose DENVax formulations induced neutralising antibody responses to all four dengue virus serotypes; 30 days after the second dose, 47 (62%) of 76 participants given vaccine seroconverted to all four serotypes and 73 (96%) participants seroconverted to three or more dengue viruses. Infectious DENVax viruses were detected in only ten (25%) of 40 participants in the low-dose group and 13 (33%) of 39 participants in the high-dose group. INTERPRETATION Our findings emphasise the acceptable tolerability and immunogenicity of the tetravalent DENVax formulations in healthy, flavivirus-naive adults. Further clinical testing of DENVax in different age groups and in dengue-endemic areas is warranted. FUNDING Takeda Vaccines.
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Affiliation(s)
| | - Ivan D Velez
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Universidad de Antioquia, Medellín, Colombia
| | | | - Liliana Lopez
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Universidad de Antioquia, Medellín, Colombia
| | - Alejandra Jimenez
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Universidad de Antioquia, Medellín, Colombia
| | | | | | | | - Karen L Boroughs
- Division of Vector Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Janae L Stovall
- Division of Vector Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Betty E Luy
- Division of Vector Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | | | | | | | | | - Claire Y-H Huang
- Division of Vector Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
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Cedillo-Barrón L, García-Cordero J, Bustos-Arriaga J, León-Juárez M, Gutiérrez-Castañeda B. Antibody response to dengue virus. Microbes Infect 2014; 16:711-20. [PMID: 25124542 DOI: 10.1016/j.micinf.2014.07.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 07/26/2014] [Accepted: 07/28/2014] [Indexed: 12/23/2022]
Abstract
In this review, we discuss the current knowledge of the role of the antibody response against dengue virus and highlight novel insights into targets recognized by the human antibody response. We also discuss how the balance of pathological and protective antibody responses in the host critically influences clinical aspects of the disease.
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Affiliation(s)
- Leticia Cedillo-Barrón
- Departamento de Biomedicina Molecular, CINVESTAV IPN, Av. IPN # 2508, Col. San Pedro Zacatenco, CP 07360 México, D.F., Mexico.
| | - Julio García-Cordero
- Departamento de Biomedicina Molecular, CINVESTAV IPN, Av. IPN # 2508, Col. San Pedro Zacatenco, CP 07360 México, D.F., Mexico
| | - José Bustos-Arriaga
- Laboratory of Infectious Diseases, National Institutes of Allergy and Infectious Diseases, Bethesda, 20892 MD, USA
| | - Moisés León-Juárez
- Departamento de Inmunobioquímica, Instituto Nacional de Perinatología, Montes Urales #800, Col. Lomas de Virreyes, 11000, Mexico
| | - Benito Gutiérrez-Castañeda
- Laboratorio de Inmunología, Facultad de Estudios Superiores Iztacala, Universidad Autónoma de México, Tlalnepantla, Estado de México, Mexico
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Zellweger RM, Shresta S. Mouse models to study dengue virus immunology and pathogenesis. Front Immunol 2014; 5:151. [PMID: 24782859 PMCID: PMC3989707 DOI: 10.3389/fimmu.2014.00151] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 03/21/2014] [Indexed: 02/01/2023] Open
Abstract
The development of a compelling murine model of dengue virus (DENV) infection has been challenging, because DENV clinical isolates do not readily replicate or cause pathology in immunocompetent mice. However, research using immunocompromised mice and/or mouse-adapted viruses allows investigation of questions that may be impossible to address in human studies. In this review, we discuss the potential strengths and limitations of existing mouse models of dengue disease. Human studies are descriptive by nature; moreover, the strain, time, and sequence of infection are often unknown. In contrast, in mice, the conditions of infection are well defined and a large number of experimental parameters can be varied at will. Therefore, mouse models offer an opportunity to experimentally test hypotheses that are based on epidemiological observations. In particular, gain-of-function or loss-of-function models can be established to assess how different components of the immune system (either alone or in combination) contribute to protection or pathogenesis during secondary infections or after vaccination. In addition, mouse models have been used for pre-clinical testing of anti-viral drugs or for vaccine development studies. Conclusions based on mouse experiments must be extrapolated to DENV-infection in humans with caution due to the inherent limitations of animal models. However, research in mouse models is a useful complement to in vitro and epidemiological data, and may delineate new areas that deserve attention during future human studies.
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Affiliation(s)
- Raphaël M Zellweger
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology , La Jolla, CA , USA
| | - Sujan Shresta
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology , La Jolla, CA , USA
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Live attenuated tetravalent dengue virus host range vaccine is immunogenic in African green monkeys following a single vaccination. J Virol 2014; 88:6729-42. [PMID: 24696467 DOI: 10.1128/jvi.00541-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
UNLABELLED The causative agent of dengue fever, dengue virus (DENV), is transmitted by mosquitoes, and as distribution of these insects has expanded, so has dengue-related disease. DENV is a member of the Flaviviridae family and has 4 distinct serotypes (DENV-1, -2, -3, and -4). No lasting cross protection is afforded to heterologous serotypes following infection by any one of the individual serotypes. The presence of nonneutralizing antibodies to one serotype can facilitate the occurrence of more-severe dengue hemorrhagic fever through immune enhancement upon infection with a second serotype. For this reason, the development of a safe, tetravalent vaccine to produce a balanced immune response to all four serotypes is critical. We have developed a novel approach to produce safe and effective live-attenuated vaccines for DENV and other insect-borne viruses. Host range (HR) mutants of each DENV serotype were created by truncating transmembrane domain 1 of the E protein and selecting for strains of DENV that replicated well in insect cells but not mammalian cells. These vaccine strains were tested for immunogenicity in African green monkeys (AGMs). No vaccine-related adverse events occurred. The vaccine strains were confirmed to be attenuated in vivo by infectious center assay (ICA). Analysis by 50% plaque reduction neutralization test (PRNT50) established that by day 62 postvaccination, 100% of animals seroconverted to DENV-1, -2, -3, and -4. Additionally, the DENV HR tetravalent vaccine (HR-Tet) showed a tetravalent anamnestic immune response in 100% (16/16) of AGMs after challenge with wild-type (WT) DENV strains. IMPORTANCE We have generated a live attenuated viral (LAV) vaccine capable of eliciting a strong immune response in African green monkeys (AGMs) in a single dose. This vaccine is delivered by injecting one of four attenuated serotypes into each limb of the animal. 100% of animals given the vaccine generated antibodies against all 4 serotypes, and this response was found to be balanced in nature. This is also one of the first studies of dengue in AGMs, and our study suggests that viremia and antibody response in AGMs may be similar to those seen in DENV infection in humans.
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Messer WB, de Alwis R, Yount BL, Royal SR, Huynh JP, Smith SA, Crowe JE, Doranz BJ, Kahle KM, Pfaff JM, White LJ, Sariol CA, de Silva AM, Baric RS. Dengue virus envelope protein domain I/II hinge determines long-lived serotype-specific dengue immunity. Proc Natl Acad Sci U S A 2014; 111:1939-44. [PMID: 24385585 PMCID: PMC3918811 DOI: 10.1073/pnas.1317350111] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The four dengue virus (DENV) serotypes, DENV-1, -2, -3, and -4, are endemic throughout tropical and subtropical regions of the world, with an estimated 390 million acute infections annually. Infection confers long-term protective immunity against the infecting serotype, but secondary infection with a different serotype carries a greater risk of potentially fatal severe dengue disease, including dengue hemorrhagic fever and dengue shock syndrome. The single most effective measure to control this threat to global health is a tetravalent DENV vaccine. To date, attempts to develop a protective vaccine have progressed slowly, partly because the targets of type-specific human neutralizing antibodies (NAbs), which are critical for long-term protection, remain poorly defined, impeding our understanding of natural immunity and hindering effective vaccine development. Here, we show that the envelope glycoprotein domain I/II hinge of DENV-3 and DENV-4 is the primary target of the long-term type-specific NAb response in humans. Transplantation of a DENV-4 hinge into a recombinant DENV-3 virus showed that the hinge determines the serotype-specific neutralizing potency of primary human and nonhuman primate DENV immune sera and that the hinge region both induces NAbs and is targeted by protective NAbs in rhesus macaques. These results suggest that the success of live dengue vaccines may depend on their ability to stimulate NAbs that target the envelope glycoprotein domain I/II hinge region. More broadly, this study shows that complex conformational antibody epitopes can be transplanted between live viruses, opening up similar possibilities for improving the breadth and specificity of vaccines for influenza, HIV, hepatitis C virus, and other clinically important viral pathogens.
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Affiliation(s)
- William B. Messer
- Department of Molecular Microbiology and Immunology and
- Division of Infectious Diseases, Department of Medicine, Oregon Health and Sciences University, Portland, OR 97239
| | - Ruklanthi de Alwis
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC 27599
| | - Boyd L. Yount
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599
| | - Scott R. Royal
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599
| | - Jeremy P. Huynh
- Department of Molecular Microbiology and Immunology and
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599
| | | | - James E. Crowe
- Pediatrics, and
- Pathology and
- Vanderbilt Vaccine Center, Vanderbilt University, Nashville, TN 37232
| | | | | | | | - Laura J. White
- Global Vaccines, Inc., Research Triangle Park, NC 27709; and
| | - Carlos A. Sariol
- Caribbean Primate Research Center and
- Departments of Microbiology and Medical Zoology and
- Internal Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico 00936
| | - Aravinda M. de Silva
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC 27599
| | - Ralph S. Baric
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, NC 27599
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599
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Detection of serotype-specific antibodies to the four dengue viruses using an immune complex binding (ICB) ELISA. PLoS Negl Trop Dis 2013; 7:e2580. [PMID: 24386498 PMCID: PMC3873247 DOI: 10.1371/journal.pntd.0002580] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Accepted: 10/29/2013] [Indexed: 02/02/2023] Open
Abstract
Background Dengue virus (DENV) infections are preferentially diagnosed by detection of specific IgM antibodies, DENV NS1 antigen assays or by amplification of viral RNA in serum samples of the patients. The type-specific immunity to the four worldwide circulating DENV serotypes can be determined by neutralization assays. An alternative to the complicated neutralization assays would be helpful to study the serotype-specific immune response in people in DENV hyperendemic areas but also in subjects upon DENV vaccination. Methods In consecutive samples of patients with DENV-1- 4 infection type-specific antibodies were detected using an immune complex binding (ICB) ELISA. During incubation of serum samples and enzyme- labeled recombinant envelope domain III (EDIII) antigens immune complexes (ICs) are formed, which are simultaneously bound to a solid phase coated with an Fc–receptor (CD32). After a single washing procedure the bound labeled ICs can be determined. To further improve type-specific reactions high concentrations of competing heterologous unlabeled ED III proteins were added to the labeled antigens. Results Follow-up serum samples of 64 patients with RT-PCR confirmed primary DENV-1, -2, -3 or -4 infections were tested against four enzyme-labeled recombinant DENV EDIII antigens. Antibodies to the EDIII antigens were found in 55 patients (sensitivity 86%). A complete agreement between the serotype detected by PCR in early samples and the serotype-specific antibody in later samples was found. Type-specific anti-EDIII antibodies were first detected 9–20 days after onset of the disease. In 21% of the samples collected from people in Vietnam secondary infections with antibodies to two serotypes could be identified. Conclusions The data obtained with the ICB-ELISA show that after primary DENV infection the corresponding type-specific antibodies are detected in almost all samples collected at least two weeks after onset of the disease. The method will be of value to determine the distribution of the various type-specific anti–DENV antibodies in DENV endemic areas. Infections with four different dengue viruses are threatening 2.5 billion people in tropical countries. Since most antibodies to these four viruses are cross-reacting, a type-specific ELISA would be valuable to study the immune response to the circulating viruses in patients but also in healthy subjects in endemic counties. Therefore a novel DENV immune complex binding (ICB) ELISA was developed to detect serotype-specific antibodies to all four dengue virus serotypes in human serum samples. The tests use labeled recombinant EDIII antigens of the four DENV strains. Numerous samples of patients with RT-PCR confirmed dengue fever were assessed by the new method. In samples of 55 patients with primary dengue fever full agreement between the serotype detected by RT-PCR and the serotype-specific antibody based on the ICB ELISA was obtained. The type-specific antibodies were not observed before the second week of illness. Our data suggest that using the ICB ELISA in healthy adult subjects in an endemic region (Vietnam) both primary and secondary infections can be identified. The method may help to analyze the distribution of the four dengue viruses in the tropics.
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Carod-Artal FJ, Wichmann O, Farrar J, Gascón J. Neurological complications of dengue virus infection. Lancet Neurol 2013; 12:906-919. [PMID: 23948177 DOI: 10.1016/s1474-4422(13)70150-9] [Citation(s) in RCA: 280] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dengue is the second most common mosquito-borne disease affecting human beings. In 2009, WHO endorsed new guidelines that, for the first time, consider neurological manifestations in the clinical case classification for severe dengue. Dengue can manifest with a wide range of neurological features, which have been noted--depending on the clinical setting--in 0·5-21% of patients with dengue admitted to hospital. Furthermore, dengue was identified in 4-47% of admissions with encephalitis-like illness in endemic areas. Neurological complications can be categorised into dengue encephalopathy (eg, caused by hepatic failure or metabolic disorders), encephalitis (caused by direct virus invasion), neuromuscular complications (eg, Guillain-Barré syndrome or transient muscle dysfunctions), and neuro-ophthalmic involvement. However, overlap of these categories is possible. In endemic countries and after travel to these regions, dengue should be considered in patients presenting with fever and acute neurological manifestations.
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Affiliation(s)
- Francisco Javier Carod-Artal
- Neurology Department, Raigmore Hospital, Inverness, UK; Medicine and Health Sciences Faculty, Universitat Internacional de Catalunya (UIC), Barcelona, Spain.
| | - Ole Wichmann
- Department for Infectious Disease Epidemiology, Robert Koch Institute, Berlin, Germany
| | - Jeremy Farrar
- Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Centre for Tropical Medicine, Oxford University, Ho Chi Minh City, Vietnam; Department of Medicine, National University of Singapore, Singapore
| | - Joaquim Gascón
- Barcelona Center for International Health Research (CRESIB), Hospital Clinic-Universitat de Barcelona, Barcelona, Spain
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30
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Chao DL, Longini IM, Halloran ME. The effects of vector movement and distribution in a mathematical model of dengue transmission. PLoS One 2013; 8:e76044. [PMID: 24204590 PMCID: PMC3804532 DOI: 10.1371/journal.pone.0076044] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 08/21/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Mathematical models have been used to study the dynamics of infectious disease outbreaks and predict the effectiveness of potential mass vaccination campaigns. However, models depend on simplifying assumptions to be tractable, and the consequences of making such assumptions need to be studied. Two assumptions usually incorporated by mathematical models of vector-borne disease transmission is homogeneous mixing among the hosts and vectors and homogeneous distribution of the vectors. METHODOLOGY/PRINCIPAL FINDINGS We explored the effects of mosquito movement and distribution in an individual-based model of dengue transmission in which humans and mosquitoes are explicitly represented in a spatial environment. We found that the limited flight range of the vector in the model greatly reduced its ability to transmit dengue among humans. A model that does not assume a limited flight range could yield similar attack rates when transmissibility of dengue was reduced by 39%. A model in which mosquitoes are distributed uniformly across locations behaves similarly to one in which the number of mosquitoes per location is drawn from an exponential distribution with a slightly higher mean number of mosquitoes per location. When the models with different assumptions were calibrated to have similar human infection attack rates, mass vaccination had nearly identical effects. CONCLUSIONS/SIGNIFICANCE Small changes in assumptions in a mathematical model of dengue transmission can greatly change its behavior, but estimates of the effectiveness of mass dengue vaccination are robust to some simplifying assumptions typically made in mathematical models of vector-borne disease.
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Affiliation(s)
- Dennis L. Chao
- Center for Statistics and Quantitative Infectious Diseases, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- * E-mail:
| | - Ira M. Longini
- Department of Biostatistics, College of Public Health and Health Professions, and Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America
| | - M. Elizabeth Halloran
- Center for Statistics and Quantitative Infectious Diseases, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Department of Biostatistics, School of Public Health, University of Washington, Seattle, Washington, United States of America
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32
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Identifying protective dengue vaccines: Guide to mastering an empirical process. Vaccine 2013; 31:4501-7. [DOI: 10.1016/j.vaccine.2013.06.079] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 06/17/2013] [Accepted: 06/26/2013] [Indexed: 11/21/2022]
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Bäck AT, Lundkvist A. Dengue viruses - an overview. Infect Ecol Epidemiol 2013; 3:19839. [PMID: 24003364 PMCID: PMC3759171 DOI: 10.3402/iee.v3i0.19839] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 07/11/2013] [Accepted: 07/16/2013] [Indexed: 12/11/2022] Open
Abstract
Dengue viruses (DENVs) cause the most common arthropod-borne viral disease in man with 50-100 million infections per year. Because of the lack of a vaccine and antiviral drugs, the sole measure of control is limiting the Aedes mosquito vectors. DENV infection can be asymptomatic or a self-limited, acute febrile disease ranging in severity. The classical form of dengue fever (DF) is characterized by high fever, headache, stomach ache, rash, myalgia, and arthralgia. Severe dengue, dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS) are accompanied by thrombocytopenia, vascular leakage, and hypotension. DSS, which can be fatal, is characterized by systemic shock. Despite intensive research, the underlying mechanisms causing severe dengue is still not well understood partly due to the lack of appropriate animal models of infection and disease. However, even though it is clear that both viral and host factors play important roles in the course of infection, a fundamental knowledge gap still remains to be filled regarding host cell tropism, crucial host immune response mechanisms, and viral markers for virulence.
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Affiliation(s)
- Anne Tuiskunen Bäck
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden ; Swedish Institute for Communicable Disease Control, Solna, Sweden ; Swedish International Development Cooperation Agency, Unit for Research Cooperation, Stockholm, Sweden
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García-Machorro J, López-González M, Barrios-Rojas O, Fernández-Pomares C, Sandoval-Montes C, Santos-Argumedo L, Villegas-Sepúlveda N, Gutiérrez-Castañeda B, Cedillo-Barrón L. DENV-2 subunit proteins fused to CR2 receptor-binding domain (P28)-induces specific and neutralizing antibodies to the Dengue virus in mice. Hum Vaccin Immunother 2013; 9:2326-35. [PMID: 23880886 DOI: 10.4161/hv.25673] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Domain III (DIII) of the dengue virus (DENV) envelope (E) protein induces strong neutralizing type-specific antibodies. In addition, a region near the fusion loop in domain II (DII) induces the production of cross-reactive antibodies with neutralizing potential. Thus, this study aimed to generate DENV-2 recombinant fusion proteins (i.e., rEII*EIII and rEII*EIII/NS1*) either alone or fused to 3 copies of P28, the minimum CR2-binding domain of the complement protein C3d. The 4 recombinant proteins were generated in a Drosophila melanogaster Schneider 2 (S2) cell system. The expression and secretion of the recombinant proteins were confirmed in vitro using immunofluorescence (IF) and western blot (WB) analyses. Human dengue immune serum samples recognized recombinant proteins. The immunogenicity of the 4 proteins in BALB/c mice was analyzed using ELISA, and the results revealed that the induced specific antibody response was higher in the groups of mice immunized with the P28 fusion proteins. Interestingly, although the 4 recombinant proteins were able to elicit high levels of neutralizing antibodies in BALB/c mice; no adjuvant effect was observed in terms of neutralizing antibodies in the groups immunized with proteins containing P28. Thus, ELISA and PRNT50 assays may evaluate different epitopes and responses, where ELISA showed a wider response that did not always correlate with neutralization. Furthermore, the elicited antibodies were able to recognize the immobilized E glycoprotein of DENV. All mice vaccinated with the DENV-2 recombinant proteins showed induction of higher levels of IgG1 antibodies than of IgG2a antibodies.
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Affiliation(s)
- Jazmín García-Machorro
- Department of Molecular Biomedicine Centre for Research and Advanced Studies (CINVESTAV-IPN) Av. IPN # 2508 Col.; San Pedro Zacatenco, D.F. Mexico, Mexico
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35
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Raviprakash K, Sun P, Raviv Y, Luke T, Martin N, Kochel T. Dengue virus photo-inactivated in presence of 1,5-iodonaphthylazide (INA) or AMT, a psoralen compound (4'-aminomethyl-trioxsalen) is highly immunogenic in mice. Hum Vaccin Immunother 2013; 9:2336-41. [PMID: 23835446 DOI: 10.4161/hv.25602] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Two novel methods of dengue virus inactivation using iodonaphthyl azide (INA) and aminomethyl trioxsalen (AMT) were compared with traditional virus inactivation by formaldehyde. The AMT inactivated dengue-2 virus retained its binding to a panel of 5 monoclonal antibodies specific for dengue-2 envelope protein, whereas inactivation by formaldehyde and INA led to 30-50% decrease in binding. All three inactivated viruses elicited high level virus neutralizing antibodies in vaccinated mice. However, only mice vaccinated with AMT inactivated virus mounted T cell responses similar to live, uninactivated virus.
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Affiliation(s)
- Kanakatte Raviprakash
- Viral & Rickettsial Diseases Department; Naval Medical Research Center; Silver Spring, MD USA
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Smith SA, de Alwis R, Kose N, Durbin AP, Whitehead SS, de Silva AM, Crowe JE. Human monoclonal antibodies derived from memory B cells following live attenuated dengue virus vaccination or natural infection exhibit similar characteristics. J Infect Dis 2013; 207:1898-908. [PMID: 23526830 DOI: 10.1093/infdis/jit119] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The immunopathogenesis of severe dengue is poorly understood, but there is concern that induction of cross-reactive nonneutralizing antibodies by infection or vaccination may increase the likelihood of severe disease during a subsequent infection. We generated a total of 63 new human monoclonal antibodies to compare the B-cell response of subjects who received the National Institutes of Health live attenuated dengue vaccine rDEN1Δ30 to that of subjects following symptomatic primary infection with DENV1. Both infection and vaccination induced serum neutralizing antibodies and DENV1-reactive peripheral blood B cells, but the magnitude of induction was lower in vaccinated individuals. Serotype cross-reactive weakly neutralizing antibodies dominated the response in both vaccinated and naturally infected subjects. Antigen specificities were very similar, with a slightly greater percentage of antibodies targeting E protein domain I/II than domain III. These data shed light on the similarity of human B-cell response to live attenuated DENV vaccine or natural infection.
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Affiliation(s)
- Scott A Smith
- Department of Medicine, Vanderbilt University Medical Center, Vanderbilt University, Nashville, Tennessee, USA
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37
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White LJ, Sariol CA, Mattocks MD, Wahala M P B W, Yingsiwaphat V, Collier ML, Whitley J, Mikkelsen R, Rodriguez IV, Martinez MI, de Silva A, Johnston RE. An alphavirus vector-based tetravalent dengue vaccine induces a rapid and protective immune response in macaques that differs qualitatively from immunity induced by live virus infection. J Virol 2013; 87:3409-24. [PMID: 23302884 PMCID: PMC3592161 DOI: 10.1128/jvi.02298-12] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 01/03/2013] [Indexed: 11/20/2022] Open
Abstract
Despite many years of research, a dengue vaccine is not available, and the more advanced live attenuated vaccine candidate in clinical trials requires multiple immunizations with long interdose periods and provides low protective efficacy. Here, we report important contributions to the development of a second-generation dengue vaccine. First, we demonstrate that a nonpropagating vaccine vector based on Venezuelan equine encephalitis virus replicon particles (VRP) expressing two configurations of dengue virus E antigen (subviral particles [prME] and soluble E dimers [E85]) successfully immunized and protected macaques against dengue virus, while antivector antibodies did not interfere with a booster immunization. Second, compared to prME-VRP, E85-VRP induced neutralizing antibodies faster, to higher titers, and with improved protective efficacy. Third, this study is the first to map antigenic domains and specificities targeted by vaccination versus natural infection, revealing that, unlike prME-VRP and live virus, E85-VRP induced only serotype-specific antibodies, which predominantly targeted EDIII, suggesting a protective mechanism different from that induced by live virus and possibly live attenuated vaccines. Fourth, a tetravalent E85-VRP dengue vaccine induced a simultaneous and protective response to all 4 serotypes after 2 doses given 6 weeks apart. Balanced responses and protection in macaques provided further support for exploring the immunogenicity and safety of this vaccine candidate in humans.
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Affiliation(s)
- Laura J White
- Global Vaccines Inc., Research Triangle Park, NC, USA.
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Expression, purification, and evaluation of diagnostic potential and immunogenicity of a recombinant NS3 protein from all serotypes of dengue virus. J Trop Med 2012; 2012:956875. [PMID: 23258983 PMCID: PMC3518973 DOI: 10.1155/2012/956875] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Revised: 09/14/2012] [Accepted: 10/18/2012] [Indexed: 11/17/2022] Open
Abstract
Dengue is one of the major public health concerns in the world. Since all the four serotypes are actively circulating in Mexico, there is a need to develop an efficient diagnosis system to improve case management of the patients. There exist few studies evaluating the use of the NS3 protein as a protective antigen against dengue virus (DENV). In this paper we show the expression of a recombinant NS3 protein from all serotypes of dengue virus (GST-DVNS3-1-4) and report a reliable "in-house detection system" for the diagnosis of dengue infection which was field-tested in a small village (Tezonapa) in the state of Veracruz, Mexico. The fusion proteins were immunogenic, inducing antibodies to be able to recognize to antigens up to a 1 : 3200 dilution. The purified proteins were used to develop an in-house detection system (ELISA) and were further tested with a panel of 239 serum samples. The in-house results were in excellent agreement with the commercial kits with κ = 0.934 ± 0.064 (95% CI = 0.808-1.061), and κ = 0.872 ± 0.048 (95% CI = 0.779-0.965) for IgM and IgG, respectively. The agreement between the NS1 antigen detection versus the rNS3 ELISA, κ = 0.837 ± 0.066 (95% CI = 0.708-0.966), was very good. Thus, these results demonstrate that recombinant NS3 proteins have potential in early diagnosis of dengue infections.
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Crill WD, Hughes HR, Trainor NB, Davis BS, Whitney MT, Chang GJJ. Sculpting humoral immunity through dengue vaccination to enhance protective immunity. Front Immunol 2012; 3:334. [PMID: 23162552 PMCID: PMC3492872 DOI: 10.3389/fimmu.2012.00334] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 10/20/2012] [Indexed: 11/13/2022] Open
Abstract
Dengue viruses (DENV) are the most important mosquito transmitted viral pathogens infecting humans. DENV infection produces a spectrum of disease, most commonly causing a self-limiting flu-like illness known as dengue fever; yet with increased frequency, manifesting as life-threatening dengue hemorrhagic fever (DHF). Waning cross-protective immunity from any of the four dengue serotypes may enhance subsequent infection with another heterologous serotype to increase the probability of DHF. Decades of effort to develop dengue vaccines are reaching the finishing line with multiple candidates in clinical trials. Nevertheless, concerns remain that imbalanced immunity, due to the prolonged prime-boost schedules currently used in clinical trials, could leave some vaccinees temporarily unprotected or with increased susceptibility to enhanced disease. Here we develop a DENV serotype 1 (DENV-1) DNA vaccine with the immunodominant cross-reactive B cell epitopes associated with immune enhancement removed. We compare wild-type (WT) with this cross-reactivity reduced (CRR) vaccine and demonstrate that both vaccines are equally protective against lethal homologous DENV-1 challenge. Under conditions mimicking natural exposure prior to acquiring protective immunity, WT vaccinated mice enhanced a normally sub-lethal heterologous DENV-2 infection resulting in DHF-like disease and 95% mortality in AG129 mice. However, CRR vaccinated mice exhibited redirected serotype-specific and protective immunity, and significantly reduced morbidity and mortality not differing from naїve mice. Thus, we demonstrate in an in vivo DENV disease model, that non-protective vaccine-induced immunity can prime vaccinees for enhanced DHF-like disease and that CRR DNA immunization significantly reduces this potential vaccine safety concern. The sculpting of immune memory by the modified vaccine and resulting redirection of humoral immunity provide insight into DENV vaccine-induced immune responses.
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Affiliation(s)
- Wayne D Crill
- Arboviral Diseases Branch, Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Service Fort Collins, CO, USA
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40
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Raviprakash K, Luke T, Doukas J, Danko J, Porter K, Burgess T, Kochel T. A dengue DNA vaccine formulated with Vaxfectin® is well tolerated, and elicits strong neutralizing antibody responses to all four dengue serotypes in New Zealand white rabbits. Hum Vaccin Immunother 2012; 8:1764-8. [PMID: 23032166 DOI: 10.4161/hv.21806] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A tetravalent DNA vaccine formulated with Vaxfectin adjuvant was shown to elicit high levels of neutralizing antibody against all four dengue virus serotypes (Porter et al., ( 16) ), warranting further testing in humans. In preparation for a phase 1 clinical testing, the vaccine and the adjuvant were manufactured under current good manufacturing practice guidelines. The formulated vaccine and the adjuvant were tested for safety and/or immunogenicity in New Zealand white rabbits using a repeat dose toxicology study. The formulated vaccine and the adjuvant were found to be well tolerated by the animals. Animals injected with formulated vaccine produced strong neutralizing antibody response to all four dengue serotypes.
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Affiliation(s)
- Kanakatte Raviprakash
- Viral & Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, USA.
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41
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Richards SL, Anderson SL, Alto BW. Vector competence of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) for dengue virus in the Florida Keys. JOURNAL OF MEDICAL ENTOMOLOGY 2012; 49:942-6. [PMID: 22897056 DOI: 10.1603/me11293] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In 2009-2011, Monroe County in southern Florida experienced locally acquired and traveler-imported focal dengue outbreaks. Aedes aegypti (L.) is the primary vector of dengue virus (DENV) worldwide, is prevalent in Monroe County, and is the suspected vector in Florida. Ae. albopictus (Skuse) is also known to be an important vector of DENV and this species is ubiquitous in Florida; however, it is not yet established in Monroe County. Florida Ae. aegypti (Key West and Stock Island geographic colonies) and Ae. albopictus (Vero Beach geographic colony) were fed blood containing 3.7 Log10 plaque-forming unit equivalents of DENV serotype 1 isolated from a patient involved in the Key West, FL, outbreak in 2010. Mosquitoes were maintained at extrinsic incubation temperatures of 28 or 30 degrees C for an incubation period of 14 d. Vector competence was assessed using rates of infection (percent with virus-positive bodies), dissemination (percent infected with virus-positive legs), and transmission (percent infected with virus-positive saliva). No significant differences were observed in rates of infection or dissemination between Ae. aegypti or Ae. albopictus at either extrinsic incubation temperature. Transmission was observed only at 28 degrees C in both Ae. aegypti (Key West) and Ae. albopictus. The assessment of local mosquito populations for their DENV vector competence is essential and will aid mosquito control operators interested in pinpointing specific vector populations for control. The extent to which vector competence is affected by seasonal changes in temperature is discussed and provides baseline risk assessment data to mosquito control agencies.
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Affiliation(s)
- Stephanie L Richards
- East Carolina University, College of Health and Human Performance, Department of Health Education and Promotion, Environmental Health Sciences Program, 3403 Carol Belk Building, Greenville, NC 27858, USA.
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Development of a robust cytopathic effect-based high-throughput screening assay to identify novel inhibitors of dengue virus. Antimicrob Agents Chemother 2012; 56:3399-401. [PMID: 22391547 DOI: 10.1128/aac.06425-11] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have developed a robust cytopathic effect-based high-throughput screening assay to identify inhibitors of dengue virus (DENV) infection. Screening of a small natural product library yielded 11 hits. Four of these were found to be potent inhibitors of DENV, although serotype differences were noted. Taken together, these data suggest that screening of larger and more complex molecule libraries may result in the identification of more potent and specific DENV inhibitors.
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