1
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Zogali V, Kiousis D, Voutyra S, Kalyva G, Abdul Mahid MB, Bist P, Ki Chan KW, Vasudevan SG, Rassias G. Carbazole to indolazepinone scaffold morphing leads to potent cell-active dengue antivirals. Eur J Med Chem 2024; 268:116213. [PMID: 38382389 DOI: 10.1016/j.ejmech.2024.116213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 01/10/2024] [Accepted: 02/01/2024] [Indexed: 02/23/2024]
Abstract
According to WHO, dengue virus is classed among major threats for future pandemics and remains at large an unmet medical need as there are currently no relevant antiviral drugs whereas vaccine developments have met with safety concerns, mostly due to secondary infections caused by antibody-dependant-enhancement in cross infections among the four dengue serotypes. This adds extra complexity in dengue antiviral research and has impeded the progress in this field. Following through our previous effort which born the allosteric, dual-mode inhibitor SP-471P (a carbazole derivative, EC50 1.1 μM, CC50 100 μM) we performed further optimisation while preserving the two arylamidoxime arms and the bromoaryl domain present in SP-471P. Examination of the relative positions of these functionalities within this three-point pharmacophore ultimately led us to an indolazepinone scaffold and our lead compound SP-1769B. SP-1769B is among the most cell-efficacious against all serotypes (DENV2/3 EC50 100 nM, DENV1/4 EC50 0.95-1.25 μM) and safest (CC50 > 100 μM) anti-dengue compounds in the literature that also completely inhibits a secondary ADE-driven infection.
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Affiliation(s)
- Vasiliki Zogali
- Department of Chemistry, University of Patras, Patra, 26504, Greece
| | | | - Stefania Voutyra
- Department of Chemistry, University of Patras, Patra, 26504, Greece
| | - Georgia Kalyva
- Department of Chemistry, University of Patras, Patra, 26504, Greece
| | | | - Pradeep Bist
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road 169857, Singapore
| | - Kitti Wing Ki Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road 169857, Singapore
| | - Subhash G Vasudevan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road 169857, Singapore; Institute for Glycomics, Griffith University, Gold Coast Campus, QLD, 4222, Australia; Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, 117545, Singapore
| | - Gerasimos Rassias
- Department of Chemistry, University of Patras, Patra, 26504, Greece.
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2
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Saleem HN, Kousar S, Jiskani AH, Sohail I, Faisal A, Saeed M. Repurposing of investigational cancer drugs: Early phase discovery of dengue virus NS2B/NS3 protease inhibitors. Arch Pharm (Weinheim) 2023; 356:e2300292. [PMID: 37582646 DOI: 10.1002/ardp.202300292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/29/2023] [Accepted: 07/31/2023] [Indexed: 08/17/2023]
Abstract
Dengue fever is a neglected vector-borne disease and is more prevalent in Asia. Currently, no specific treatment is available. Given the time and cost of de novo drug discovery and development, an alternative option of drug repurposing is becoming an effective tool. We screened a library of 1127 pharmacologically active, metabolically stable, and structurally diverse small anticancer molecules to identify inhibitors of the dengue virus (DENV) NS2B/NS3 protease. Enzyme kinetics and inhibition data revealed four B-cell lymphoma 2 inhibitors, that is, ABT263, ABT737, AT101, and TW37, as potent inhibitors of DENV NS2B/NS3 protease, with IC50 values of 0.86, 1.15, 0.81, and 0.89 µM, respectively. Mode of inhibition experiments and computational docking analyses indicated that ABT263 and ABT737 are competitive inhibitors, whereas AT101 and TW37 are noncompetitive inhibitors of the protease. With further evaluation, the identified inhibitors of the DENV NS2B/NS3 protease have the potential to be developed into specific anti-dengue therapeutics.
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Affiliation(s)
- Hafiza N Saleem
- Department of Chemistry and Chemical Engineering, SBA School of Science and Engineering, Lahore University of Management Sciences (LUMS), Lahore, Pakistan
| | - Summara Kousar
- Department of Chemistry and Chemical Engineering, SBA School of Science and Engineering, Lahore University of Management Sciences (LUMS), Lahore, Pakistan
| | - Ammar Hassan Jiskani
- Department of Chemistry and Chemical Engineering, SBA School of Science and Engineering, Lahore University of Management Sciences (LUMS), Lahore, Pakistan
| | - Iqra Sohail
- Department of Life Sciences, SBA School of Science and Engineering, Lahore University of Management Sciences (LUMS), Lahore, Pakistan
| | - Amir Faisal
- Department of Life Sciences, SBA School of Science and Engineering, Lahore University of Management Sciences (LUMS), Lahore, Pakistan
| | - Muhammad Saeed
- Department of Chemistry and Chemical Engineering, SBA School of Science and Engineering, Lahore University of Management Sciences (LUMS), Lahore, Pakistan
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3
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Sarker A, Dhama N, Gupta RD. Dengue virus neutralizing antibody: a review of targets, cross-reactivity, and antibody-dependent enhancement. Front Immunol 2023; 14:1200195. [PMID: 37334355 PMCID: PMC10272415 DOI: 10.3389/fimmu.2023.1200195] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 05/19/2023] [Indexed: 06/20/2023] Open
Abstract
Dengue is the most common viral infection spread by mosquitoes, prevalent in tropical countries. The acute dengue virus (DENV) infection is a benign and primarily febrile illness. However, secondary infection with alternative serotypes can worsen the condition, leading to severe and potentially fatal dengue. The antibody raised by the vaccine or the primary infections are frequently cross-reactive; however, weakly neutralizing, and during subsequent infection, they may increase the odds of antibody-dependent enhancement (ADE). Despite that, many neutralizing antibodies have been identified against the DENV, which are thought to be useful in reducing dengue severity. Indeed, an antibody must be free from ADE for therapeutic application, as it is pretty common in dengue infection and escalates disease severity. Therefore, this review has described the critical characteristics of DENV and the potential immune targets in general. The primary emphasis is given to the envelope protein of DENV, where potential epitopes targeted for generating serotype-specific and cross-reactive antibodies have critically been described. In addition, a novel class of highly neutralizing antibodies targeted to the quaternary structure, similar to viral particles, has also been described. Lastly, we have discussed different aspects of the pathogenesis and ADE, which would provide significant insights into developing safe and effective antibody therapeutics and equivalent protein subunit vaccines.
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4
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Jamora RDG, Lim MAR, Espiritu AI. Philippine immunization coverage and dengvaxia: An infodemiological study. Pediatr Int 2023; 65:e15623. [PMID: 37767858 DOI: 10.1111/ped.15623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 09/29/2023]
Abstract
BACKGROUND A dengue vaccine, dengvaxia, was licensed for the first time in 2015. It was approved for use in 11 countries where dengue infection is endemic, including the Philippines. In November 2017, controversy arose in the Philippines regarding the dengvaxia vaccine. We hypothesized that the dengvaxia controversy might be correlated with immunization coverage in the Philippines. METHODS We performed an analytical and infodemiological study on web-based interest in dengvaxia, both globally and in 18 dengue endemic countries, from 2015 to 2020 using Google Trends™. Comparisons were made with search trends for the components of the National Immunization Program (NIP) and vaccine coverage by computing the Pearson product-moment correlation coefficient (r) between each variable. RESULTS Among the 18 countries included, the Philippines had the highest search volume index for dengvaxia, with peaks in searches coinciding with that of worldwide search trends. There was no correlation between the relative search volume for dengvaxia with that of vaccines included in the NIP in the Philippines from 2015 to 2020. There was no significant correlation between web-based interest in dengvaxia and the estimated immunization coverage from 2015 to 2019. CONCLUSION There was no significant correlation between web-based interest in dengvaxia, the vaccines in the NIP, and national immunization coverage.
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Affiliation(s)
- Roland Dominic G Jamora
- Division of Adult Neurology, Department of Neurosciences, College of Medicine - Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Marie Abigail R Lim
- Department of Pediatrics, College of Medicine - Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Adrian I Espiritu
- Division of Adult Neurology, Department of Neurosciences, College of Medicine - Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
- Department of Clinical Epidemiology, College of Medicine, University of the Philippines Manila, Ermita, Philippines
- Division of Neurology, Department of Medicine, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
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5
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Dengue, West Nile, and Zika Viruses: Potential Novel Antiviral Biologics Drugs Currently at Discovery and Preclinical Development Stages. Pharmaceutics 2022; 14:pharmaceutics14112535. [PMID: 36432726 PMCID: PMC9697021 DOI: 10.3390/pharmaceutics14112535] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 11/07/2022] [Accepted: 11/15/2022] [Indexed: 11/22/2022] Open
Abstract
Dengue, West Nile and Zika viruses are vector-borne flaviviruses responsible for numerous disease outbreaks in both Hemispheres. Despite relatively low mortality, infection may lead to potentially severe situations such as (depending on the virus): hypovolemic shock, encephalitis, acute flaccid paralysis, Guillain-Barré syndrome, congenital malformations (e.g., microcephaly) and, in some situations, death. Moreover, outbreaks also have major socioeconomic repercussions, especially in already vulnerable societies. Thus far, only generic symptoms relief is possible, as there are no specific treatments available yet. Dengvaxia was the world's first dengue vaccine. However, it is not fully effective. Prophylactic approaches against West Nile and Zika viruses are even more limited. Therefore, therapeutic strategies are required and will be discussed hereafter. We will first briefly present these viruses' epidemiology, life cycle and structure. Then, we introduce the clinical presentation, diagnosis approaches and available vaccines. Finally, we list and discuss promising compounds at discovery and preclinical development stages already deposited at the GlobalData database and divided into three main types, according to therapeutic molecule: antibody-based, peptide-based molecules and, other compounds. To conclude, we discuss and compare promising developments, useful for future therapies against these three flaviviruses of major concern to human health.
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6
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Shimizu J, Sasaki T, Yamanaka A, Ichihara Y, Koketsu R, Samune Y, Cruz P, Sato K, Tanga N, Yoshimura Y, Murakami A, Yamada M, Itoi K, Nakayama EE, Miyazaki K, Shioda T. The potential of COVID-19 patients' sera to cause antibody-dependent enhancement of infection and IL-6 production. Sci Rep 2021; 11:23713. [PMID: 34887501 PMCID: PMC8660863 DOI: 10.1038/s41598-021-03273-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 11/24/2021] [Indexed: 02/06/2023] Open
Abstract
Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), many vaccine trials have been initiated. An important goal of vaccination is the development of neutralizing antibody (Ab) against SARS-CoV-2. However, the possible induction of antibody-dependent enhancement (ADE) of infection, which is known for other coronaviruses and dengue virus infections, is a particular concern in vaccine development. Here, we demonstrated that human iPS cell-derived, immortalized, and ACE2- and TMPRSS2-expressing myeloid cell lines are useful as host cells for SARS-CoV-2 infection. The established cell lines were cloned and screened based on their function in terms of susceptibility to SARS-CoV-2-infection or IL-6 productivity. Using the resulting K-ML2 (AT) clone 35 for SARS-CoV-2-infection or its subclone 35–40 for IL-6 productivity, it was possible to evaluate the potential of sera from severe COVID-19 patients to cause ADE and to stimulate IL-6 production upon infection with SARS-CoV-2.
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Affiliation(s)
- Jun Shimizu
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Tadahiro Sasaki
- Department of Viral Infection, Research Institute for Microbial Diseases, Osaka University, 3-1, Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Atsushi Yamanaka
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan.,Faculty of Tropical Medicine, Mahidol-Osaka Center for Infectious Diseases, Mahidol University, Bangkok, Thailand
| | - Yoko Ichihara
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Ritsuko Koketsu
- Department of Viral Infection, Research Institute for Microbial Diseases, Osaka University, 3-1, Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Yoshihiro Samune
- Department of Viral Infection, Research Institute for Microbial Diseases, Osaka University, 3-1, Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Pedro Cruz
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Kei Sato
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Naomi Tanga
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Yuka Yoshimura
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Ami Murakami
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Misuzu Yamada
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Kiyoe Itoi
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan
| | - Emi E Nakayama
- Department of Viral Infection, Research Institute for Microbial Diseases, Osaka University, 3-1, Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Kazuo Miyazaki
- MiCAN Technologies Inc., KKVP 1-36, Goryo-ohara, Nishikyo-Ku, Kyoto, 615-8245, Japan.
| | - Tatsuo Shioda
- Department of Viral Infection, Research Institute for Microbial Diseases, Osaka University, 3-1, Yamada-oka, Suita, Osaka, 565-0871, Japan. .,Faculty of Tropical Medicine, Mahidol-Osaka Center for Infectious Diseases, Mahidol University, Bangkok, Thailand.
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7
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Bonheur AN, Thomas S, Soshnick SH, McGibbon E, Dupuis AP, Hull R, Slavinski S, Del Rosso PE, Weiss D, Hunt DT, McCabe ME, Dean AB, Folkerth R, Laib AM, Wong SJ. A fatal case report of antibody-dependent enhancement of dengue virus type 1 following remote Zika virus infection. BMC Infect Dis 2021; 21:749. [PMID: 34348665 PMCID: PMC8334327 DOI: 10.1186/s12879-021-06482-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 07/27/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dengue virus (DENV) is endemic in many parts of the world. Antibody dependent enhancement (ADE) in DENV infections occurs when a person with primary immunity is infected by a second, different DENV strain. Antibodies to Zika virus (ZIKV), which emerged in the Western Hemisphere in 2015, are cross reactive with DENV and theoretically could provoke ADE in a DENV naïve individual. CASE PRESENTATION DENV infection was suspected in a child who had recently returned from a one-month stay in the Dominican Republic. The child presented with fever, vomiting, abdominal pain, and in hypovolemic shock. Volume and pressor resuscitation were unsuccessful, and the child died less than 24 h after hospitalization. Laboratory results suggested an early acute first DENV infection since serum, plasma, and spinal fluid had DENV1 detected by polymerase chain reaction (PCR), yet the serum lacked IgG antibodies to DENV nonstructural protein 1 (NS1) of all four DENV serotypes. This acute DENV infection occurred in the presence of a remote ZIKV infection as determined by antibodies to ZIKV NS1 envelope by multiplex microsphere immunoassay and an exceptionally high plaque reduction neutralization titer to ZIKV. ZIKV IgG avidity index was high, confirming a past infection. DENV1 RNA was detected in all ten organs and tissues examined by PCR. The severe and fatal complications reported here suggest that a remote ZIKV infection may provoke an exaggerated immune response leading to hypovolemic shock when primarily infected by DENV1. CONCLUSION We report the first known patient in the United States with a rapidly progressive and fatal case of travel-associated DENV in which prior exposure to ZIKV likely played a role in triggering an ADE phenomenon. This association of prior ZIKV immunity and subsequent new dengue infection is a worrisome phenomenon and an important contribution to the body of knowledge on immunity to flaviviruses.
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Affiliation(s)
- Ashley N Bonheur
- Division of Pediatric Critical Care Medicine, The Children's Hospital at Montefiore/Albert Einstein College of Medicine, Bronx, NY, USA
| | - Sarah Thomas
- Office of the New York City Chief Medical Examiner, New York, NY, USA
| | - Sara H Soshnick
- Division of Pediatric Critical Care Medicine, The Children's Hospital at Montefiore/Albert Einstein College of Medicine, Bronx, NY, USA
| | - Emily McGibbon
- New York City Department of Health and Mental Hygiene, Queens, NY, USA
| | - Alan P Dupuis
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Rene Hull
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Sally Slavinski
- New York City Department of Health and Mental Hygiene, Queens, NY, USA
| | - Paula E Del Rosso
- New York City Department of Health and Mental Hygiene, Queens, NY, USA
| | - Don Weiss
- New York City Department of Health and Mental Hygiene, Queens, NY, USA.
| | - Danielle T Hunt
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Megan E McCabe
- Division of Pediatric Critical Care Medicine, The Children's Hospital at Montefiore/Albert Einstein College of Medicine, Bronx, NY, USA
| | - Amy B Dean
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Rebecca Folkerth
- Office of the New York City Chief Medical Examiner, New York, NY, USA
| | - Anne M Laib
- Office of the New York City Chief Medical Examiner, New York, NY, USA
| | - Susan J Wong
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
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8
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Amidoxime prodrugs convert to potent cell-active multimodal inhibitors of the dengue virus protease. Eur J Med Chem 2021; 224:113695. [PMID: 34298282 DOI: 10.1016/j.ejmech.2021.113695] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/05/2021] [Accepted: 07/07/2021] [Indexed: 12/16/2022]
Abstract
The flavivirus genus of the Flaviviridae family comprises Dengue, Zika and West-Nile viruses which constitute unmet medical needs as neither appropriate antivirals nor safe vaccines are available. The dengue NS2BNS3 protease is one of the most promising validated targets for developing a dengue treatment however reported protease inhibitors suffer from toxicity and cellular inefficacy. Here we report SAR on our previously reported Zika-active carbazole scaffold, culminating prodrug compound SP-471P (EC50 1.10 μM, CC50 > 100 μM) that generates SP-471; one of the most potent, non-cytotoxic and cell-active protease inhibitors described in the dengue literature. In cell-based assays, SP-471P leads to inhibition of viral RNA replication and complete abolishment of infective viral particle production even when administered 6 h post-infection. Mechanistically, SP-471 appears to inhibit both normal intermolecular protease processes and intramolecular cleavage events at the NS2BNS3 junction, as well as at NS3 internal sites, all critical for virus replication. These render SP-471 a unique to date multimodal inhibitor of the dengue protease.
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9
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Antibody-dependent enhancement representing in vitro infective progeny virus titer correlates with the viremia level in dengue patients. Sci Rep 2021; 11:12354. [PMID: 34117329 PMCID: PMC8196181 DOI: 10.1038/s41598-021-91793-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/01/2021] [Indexed: 12/13/2022] Open
Abstract
Dengue virus (DENV) causes dengue fever (DF) and dengue hemorrhagic fever in humans. Some DF patients suddenly develop severe symptoms around the defervescent period. Although the pathogenic mechanism of the severe symptoms has not been fully elucidated, the viremia level in the early phase has been shown to correlate with the disease severity. One of the hypotheses is that a phenomenon called antibody-dependent enhancement (ADE) of infection leads to high level of viremia. To examine the plausibility of this hypothesis, we examined the relationship between in vitro ADE activity and in vivo viral load quantity in six patients with dengue diseases. Blood samples were collected at multiple time points between the acute and defervescent phases, and the balance between neutralizing and enhancing activities against the autologous and prototype viruses was examined. As the antibody levels against DENV were rapidly increased, ADE activity was decreased over time or partially maintained against some viruses at low serum dilution. In addition, positive correlations were observed between ADE activity representing in vitro progeny virus production and viremia levels in patient plasma samples. The measurement of ADE activity in dengue-seropositive samples may help to predict the level of viral load in the subsequent DENV infection.
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10
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Gambino F, Tai W, Voronin D, Zhang Y, Zhang X, Shi J, Wang X, Wang N, Du L, Qiao L. A vaccine inducing solely cytotoxic T lymphocytes fully prevents Zika virus infection and fetal damage. Cell Rep 2021; 35:109107. [PMID: 33979612 PMCID: PMC8742672 DOI: 10.1016/j.celrep.2021.109107] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 03/20/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023] Open
Abstract
As vaccine-induced non-neutralizing antibodies may cause antibody-dependent enhancement of Zika virus (ZIKV) infection, we test a vaccine that induces only specific cytotoxic T lymphocytes (CTLs) without specific antibodies. We construct a DNA vaccine expressing a ubiquitinated and rearranged ZIKV non-structural protein 3 (NS3). The protein is immediately degraded and processed in the proteasome for presentation via major histocompatibility complex (MHC) class I for CTL generation. We immunize Ifnar1-/- adult mice with the ubiquitin/NS3 vaccine, impregnate them, and challenge them with ZIKV. Our data show that the vaccine greatly reduces viral titers in reproductive organs and other tissues of adult mice. All mice immunized with the vaccine survived after ZIKV challenge. The vaccine remarkably reduces placenta damage and levels of pro-inflammatory cytokines, and it fully protects fetuses from damage. CD8+ CTLs are essential in protection, as demonstrated via depletion experiments. Our study provides a strategy to develop safe and effective vaccines against viral infections.
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Affiliation(s)
- Frank Gambino
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA,These authors contributed equally
| | - Wanbo Tai
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA,These authors contributed equally
| | - Denis Voronin
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Yi Zhang
- Biotherapy Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Xiujuan Zhang
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Juan Shi
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Xinyi Wang
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Ning Wang
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Lanying Du
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA,Senior author,Correspondence: (L.D.), (L.Q.)
| | - Liang Qiao
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA,Senior author,Lead contact,Correspondence: (L.D.), (L.Q.)
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11
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Universal Dengue Vaccine Elicits Neutralizing Antibodies against Strains from All Four Dengue Virus Serotypes. J Virol 2021; 95:JVI.00658-20. [PMID: 33208445 DOI: 10.1128/jvi.00658-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 11/02/2020] [Indexed: 12/22/2022] Open
Abstract
Any potential dengue virus (DENV) vaccine needs to elicit protective immunity against strains from all four serotypes to avoid potential antibody-dependent enhancement (ADE). In this study, four independent DENV envelope (E) glycoproteins were generated using wild-type E sequences from viruses isolated between 1943 and 2006 using computationally optimized broadly reactive antigen (COBRA) methodology. COBRA and wild-type E antigens were expressed on the surface of subvirion viral particles (SVPs). Four separate wild-type E antigens were used for each serotype. Mice vaccinated with wild-type DENV SVPs had anti-E IgG antibodies that neutralized serotype-specific viruses. COBRA DENV SVPs elicited a broader breadth of antibodies that neutralized strains across all four serotypes. Two COBRA DENV vaccine candidates that elicited the broadest breadth of neutralizing antibodies in mice were used to vaccinate rhesus macaques (Macaca mulatta) that either were immunologically naive to any DENV serotype or had preexisting antibodies to DENV. Antibodies elicited by COBRA DENV E immunogens neutralized all 12 strains of DENV in vitro, which was comparable to antibodies elicited by a tetravalent wild-type E SVP vaccination mixture. Therefore, using a single DENV COBRA E protein can elicit neutralizing antibodies against strains representing all four serotypes of DENV in both naive and dengue virus-preimmune populations.IMPORTANCE Dengue virus infects millions of people living in tropical areas of the world. Dengue virus-induced diseases can range from mild to severe with death. An effective vaccine will need to neutralize viruses from all four serotypes of dengue virus without inducing enhanced disease. A dengue virus E vaccine candidate generated by computationally optimized broadly reactive antigen algorithms elicits broadly neutralizing protection for currently circulating strains from all four serotypes regardless of immune status. Most dengue vaccines in development formulate four separate components based on prM-E from a wild-type strain representing each serotype. Designing a monovalent vaccine that elicits protective immunity against all four serotypes is an effective and economical strategy.
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12
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Maier SB, Massad E, Amaku M, Burattini MN, Greenhalgh D. The optimal age of vaccination against dengue in Brazil based on serotype-specific forces of infection derived from serological data. MATHEMATICAL MEDICINE AND BIOLOGY-A JOURNAL OF THE IMA 2020; 38:1-27. [PMID: 32671383 DOI: 10.1093/imammb/dqaa007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 06/06/2020] [Accepted: 06/06/2020] [Indexed: 11/14/2022]
Abstract
In this paper, we study a single serotype transmission model of dengue to determine the optimal vaccination age for Dengvaxia. The transmission dynamics are modelled with an age-dependent force of infection. The force of infection for each serotype is derived from the serological profile of dengue in Brazil without serotype distinction and from serotype-specific reported cases. The risk due to an infection is measured by the probability of requiring hospitalization based on Brazilian Ministry of Health data. The optimal vaccination age is determined for any number and combination of the four distinct dengue virus serotypes DENv1-4. The lifetime expected risk is adapted to include antibody dependent enhancement (ADE) and permanent cross-immunity after two heterologous infections. The risk is assumed to be serostatus-dependent. The optimal vaccination age is computed for constant, serostatus-specific vaccine efficacies. Additionally, the vaccination age is restricted to conform to the licence of Dengvaxia in Brazil and the achievable and minimal lifetime expected risks are compared. The optimal vaccination age obtained for the risk of hospitalization varies significantly with the assumptions relating to ADE and cross-immunity. Risk-free primary infections lead to higher optimal vaccination ages, as do asymptomatic third and fourth infections. Sometimes vaccination is not recommended at all, e.g. for any endemic area with a single serotype if primary infections are risk-free. Restricting the vaccination age to Dengvaxia licensed ages mostly leads to only a slightly higher lifetime expected risk and the vaccine should be administered as close as possible to the optimal vaccination age.
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Affiliation(s)
- Sandra B Maier
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow G1 1XH, UK
| | - Eduardo Massad
- School of Applied Mathematics, Fundacao Getulio Vargas, Rio de Janeiro, Brazil, LIM01-Hospital de Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil, London School of Hygiene and Tropical Medicine, London, UK
| | - Marcos Amaku
- LIM01-Hospital de Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Marcelo N Burattini
- LIM01-Hospital de Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil, Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - David Greenhalgh
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow G1 1XH, UK
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A Chimeric Japanese Encephalitis Vaccine Protects against Lethal Yellow Fever Virus Infection without Inducing Neutralizing Antibodies. mBio 2020; 11:mBio.02494-19. [PMID: 32265332 PMCID: PMC7157777 DOI: 10.1128/mbio.02494-19] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Efficient and safe vaccines against yellow fever (e.g., YFV-17D) that provide long-lasting protection by rapidly inducing neutralizing antibody responses exist. However, the vaccine supply cannot cope with an increasing demand posed by urban outbreaks in recent years. Here we report that JE-CVax/Imojev, a YFV-17D-based chimeric Japanese encephalitis vaccine, also efficiently protects against YFV infection in mice. In case of shortage of the YFV vaccine during yellow fever outbreaks, (off-label) use of JE-CVax/Imojev may be considered. Moreover, wider use of JE-CVax/Imojev in Asia may lower the risk of the much-feared YFV spillover to the continent. More generally, chimeric vaccines that combine surface antigens and replication machineries of two distinct flaviviruses may be considered dual vaccines for the latter pathogen without induction of surface-specific antibodies. Following this rationale, novel flavivirus vaccines that do not hold a risk for antibody-dependent enhancement (ADE) of infection (inherent to current dengue vaccines and dengue vaccine candidates) could be designed. Recent outbreaks of yellow fever virus (YFV) in West Africa and Brazil resulted in rapid depletion of global vaccine emergency stockpiles and raised concerns about being unprepared against future YFV epidemics. Here we report that a live attenuated virus similar to the Japanese encephalitis virus (JEV) vaccine JE-CVax/Imojev that consists of YFV-17D vaccine from which the structural (prM/E) genes have been replaced with those of the JEV SA14-14-2 vaccine strain confers full protection in mice against lethal YFV challenge. In contrast to the YFV-17D-mediated protection against YFV, this protection is not mediated by neutralizing antibodies but correlates with YFV-specific nonneutralizing antibodies and T cell responses against cell-associated YFV NS1 and other YFV nonstructural (NS) proteins. Our findings reveal the potential of YFV NS proteins to mediate protection and demonstrate that chimeric flavivirus vaccines, such as Imojev, could confer protection against two flaviviruses. This dual protection may have implications for the possible off-label use of JE-CVax in case of emergency and vaccine shortage during YFV outbreaks. In addition, populations in Asia that have been vaccinated with Imojev may already be protected against YFV should outbreaks ever occur on that continent, as several countries/regions in the Asia-Pacific are vulnerable to international spread of the YFV.
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14
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Hamdani SS, Khan BA, Hameed S, Batool F, Saleem HN, Mughal EU, Saeed M. Synthesis and evaluation of novel S-benzyl- and S-alkylphthalimide- oxadiazole -benzenesulfonamide hybrids as inhibitors of dengue virus protease. Bioorg Chem 2020; 96:103567. [PMID: 32062063 DOI: 10.1016/j.bioorg.2020.103567] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 01/01/2020] [Accepted: 01/02/2020] [Indexed: 12/18/2022]
Abstract
Direct acting antiviral drugs (DAADs) are becoming therapeutics of choice for the treatment of viral infections. Successful development of anti HIV and HCV drugs by targeting the viral proteases has provided impetus for discovering newer DAADs. Dengue virus (DENV) protease, which is composed of two nonstructural proteins, NS2B and NS3pro, can be likewise exploited for discovering new anti-dengue therapeutics. In this study, we have linked together two pharmaceutically interesting motifs, namely 1,3,4-oxadiazole and benzenesulfonamide in two alternative series to develop novel S-benzylated and S-alkylphthalimidated hybrids. For the first series of hybrids, 4-aminobenzoic acid (1) was reacted with substituted benzenesulfonyl chlorides via its amino group, whereas the carboxylic acid side was elaborated to sulfonamido-1,3,4-oxadiazole-2-thiols (6a/b) in three steps. At this stage, the intermediates 6a/b were bifurcated to either S-alkylphthalimidated (8a-j) or S-benzylated (9a-c) hybrids by reacting with corresponding halides. For the alternative series of hybrids, the carboxylic acid group of probenecid (10) was similarly elaborated to sulfonamido-1,3,4-oxadiazole-2-thiols (13), and diverged to S-alkylphthalimidated (14a-f) and S-benzylated hybrids (15a-e). Bioactivity assays demonstrated that 8g and 8h are the most potent inhibitors among the synthesized analogs, exhibiting the IC50 values of 13.9 μM and 15.1 μM, respectively. Computational assessment predicted the binding of the inhibitors at an allosteric site developed in the open conformation of DENV2 NS2B/NS3pro. Taken together these findings point out that the synthesized hybrid inhibitors possess a great potential for further antiviral drug development.
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Affiliation(s)
- Syeda Shamila Hamdani
- Department of Chemistry, University of Azad Jammu and Kashmir, Muzaffarabad 13100 AJK, Pakistan; Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Bilal Ahmad Khan
- Department of Chemistry, University of Azad Jammu and Kashmir, Muzaffarabad 13100 AJK, Pakistan.
| | - Shahid Hameed
- Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Farwa Batool
- Department of Chemistry and Chemical Engineering, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore 54792 Pakistan
| | - Hafiza Nosheen Saleem
- Department of Chemistry and Chemical Engineering, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore 54792 Pakistan
| | | | - Muhammad Saeed
- Department of Chemistry and Chemical Engineering, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, Lahore 54792 Pakistan.
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15
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Mehta N, Perrais B, Martin K, Kumar A, Hobman TC, Cabalfin-Chua MN, Donaldo ME, Siose Painaga MS, Gaite JY, Tran V, Kain KC, Hawkes MT, Yanow SK. A Direct from Blood/Plasma Reverse Transcription-Polymerase Chain Reaction for Dengue Virus Detection in Point-of-Care Settings. Am J Trop Med Hyg 2020; 100:1534-1540. [PMID: 30994095 DOI: 10.4269/ajtmh.19-0138] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Infection with dengue virus (DENV) is widespread across tropical regions and can result in severe disease. Early diagnosis is important both for patient management and to differentiate infections that present with similar symptoms, such as malaria, chikungunya, and Zika. Rapid diagnostic tests that are used presently for point-of-care detection of DENV antigens lack the sensitivity of molecular diagnostics that detect viral RNA. However, no molecular diagnostic test for DENV is available for use in field settings. In this study, we developed and validated a reverse transcription-polymerase chain reaction (RT-PCR) for the detection of DENV adapted for use in field settings. Reverse transcription-polymerase chain reaction was performed directly from plasma samples without RNA extraction. The assay detected all four serotypes of DENV spiked into blood or plasma. Our RT-PCR does not cross-react with pathogens that cause symptoms that overlap with dengue infection. The test performed equally well in a conventional laboratory qPCR instrument and a small, low-cost portable instrument that can be used in a field setting. The lower limit of detection for the assay was 1 × 104 genome copy equivalents/mL in blood. Finally, we validated our test using 126 archived patient samples. The sensitivity of our RT-PCR was 76.7% (95% CI: 65.8-87.9%) on the conventional instrument, and 78.3% (95% CI: 65.8-87.9%) on the field instrument, when compared with the RealStar Dengue RT-PCR Kit 2.0. The molecular test described here is user-friendly, low-cost, and can be used in regions with limited laboratory capabilities.
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Affiliation(s)
- Ninad Mehta
- School of Public Health, University of Alberta, Edmonton, Canada
| | - Bastien Perrais
- School of Public Health, University of Alberta, Edmonton, Canada
| | - Kimberly Martin
- School of Public Health, University of Alberta, Edmonton, Canada
| | - Anil Kumar
- Department of Cell Biology, University of Alberta, Edmonton, Canada
| | - Tom C Hobman
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada.,Department of Cell Biology, University of Alberta, Edmonton, Canada
| | - Mary Noreen Cabalfin-Chua
- Section of Pediatric Infectious Diseases, Department of Pediatrics, Chong Hua Hospital, Cebu, Philippines
| | | | | | | | - Vanessa Tran
- Tropical Disease Unit, The University Health Network-Toronto General Hospital, University of Toronto, Toronto, Canada
| | - Kevin C Kain
- Tropical Disease Unit, The University Health Network-Toronto General Hospital, University of Toronto, Toronto, Canada
| | - Michael T Hawkes
- School of Public Health, University of Alberta, Edmonton, Canada.,Women and Children's Health Research Institute, Edmonton, Canada.,Stollery Science Lab, Edmonton, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Canada
| | - Stephanie K Yanow
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada.,School of Public Health, University of Alberta, Edmonton, Canada
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16
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Buchman A, Gamez S, Li M, Antoshechkin I, Li HH, Wang HW, Chen CH, Klein MJ, Duchemin JB, Crowe JE, Paradkar PN, Akbari OS. Broad dengue neutralization in mosquitoes expressing an engineered antibody. PLoS Pathog 2020; 16:e1008103. [PMID: 31945137 PMCID: PMC6964813 DOI: 10.1371/journal.ppat.1008103] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 09/23/2019] [Indexed: 12/11/2022] Open
Abstract
With dengue virus (DENV) becoming endemic in tropical and subtropical regions worldwide, there is a pressing global demand for effective strategies to control the mosquitoes that spread this disease. Recent advances in genetic engineering technologies have made it possible to create mosquitoes with reduced vector competence, limiting their ability to acquire and transmit pathogens. Here we describe the development of Aedes aegypti mosquitoes synthetically engineered to impede vector competence to DENV. These mosquitoes express a gene encoding an engineered single-chain variable fragment derived from a broadly neutralizing DENV human monoclonal antibody and have significantly reduced viral infection, dissemination, and transmission rates for all four major antigenically distinct DENV serotypes. Importantly, this is the first engineered approach that targets all DENV serotypes, which is crucial for effective disease suppression. These results provide a compelling route for developing effective genetic-based DENV control strategies, which could be extended to curtail other arboviruses.
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Affiliation(s)
- Anna Buchman
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Stephanie Gamez
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Ming Li
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Igor Antoshechkin
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, United States of America
| | - Hsing-Han Li
- Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Zhunan, Taiwan
| | - Hsin-Wei Wang
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Zhunan, Taiwan
| | - Chun-Hong Chen
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Zhunan, Taiwan
| | - Melissa J. Klein
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, VIC, Australia
| | - Jean-Bernard Duchemin
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, VIC, Australia
| | - James E. Crowe
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Departments of Pediatrics, Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Prasad N. Paradkar
- CSIRO Health and Biosecurity, Australian Animal Health Laboratory, Geelong, VIC, Australia
| | - Omar S. Akbari
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California, United States of America
- Tata Institute for Genetics and Society-UCSD, La Jolla, California, United States of America
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17
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Reed SL, McKerrow JH. Why Funding for Neglected Tropical Diseases Should Be a Global Priority. Clin Infect Dis 2019; 67:323-326. [PMID: 29688342 DOI: 10.1093/cid/ciy349] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/19/2018] [Indexed: 01/01/2023] Open
Abstract
Neglected tropical diseases affect >1 billion of the world's poorest persons. Control programs range from near-elimination (dracunculiasis) to increasing prevalence (dengue and cutaneous leishmaniasis). These are some of the most cost-effective public health interventions and should be a global priority.
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Affiliation(s)
- Sharon L Reed
- Departments of Pathology and Medicine, UC San Diego Health
| | - James H McKerrow
- Skaggs School of Pharmacy and Pharmaceutical Science, University of California, San Diego
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18
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Lasco G, Larson HJ. Medical populism and immunisation programmes: Illustrative examples and consequences for public health. Glob Public Health 2019; 15:334-344. [DOI: 10.1080/17441692.2019.1680724] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Gideon Lasco
- Department of Anthropology, University of the Philippines Diliman Quezon City, Philippines
- Development Studies Program, Ateneo de Manila University, Quezon City, Philippines
| | - Heidi J. Larson
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
- Institute of Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
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19
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20
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Medone P, Hernï Ndez-Suï Rez CM. 'Swimming mosquitoes': a key stepping stone to prevent Dengue, Zika and Chikungunya: an educative experience in Colima, Mexico. HEALTH EDUCATION RESEARCH 2019; 34:389-399. [PMID: 31329869 DOI: 10.1093/her/cyz012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 04/16/2019] [Indexed: 06/10/2023]
Abstract
Dengue, Zika and Chikungunya arboviruses (DZC), mainly transmitted by mosquito Aedes aegypti, are global health public issues affecting 390 million people each year. In most endemic countries, vector control strategies have been focused on reducing breeding sites and adult mosquito populations. Most health communication strategies have pointed out adult mosquito as the main responsible of the transmission, persuading people to eliminate domestic containers. However, it is not clear how should people understand the relationship between adult mosquitoes and water domestic containers. So, the main goal of the present study was to assess the people understanding of this relationship. Results showed that most people associate adult mosquitoes with DZC, but only few could associate swimming larvae with mosquitoes. The unawareness of larva presence leads to an underestimation of risk perception about DZC transmission. In this context, we consider that educative interventions for health promotion, based on meaningful knowledge and social representations arise as long-term strategies to control transmission of vector-borne diseases. Here, we propose innovative health strategies focused on increase the risk perception about swimming larvae, considering social representations, which may be a key stepping stone to increase people adherence to massive campaigns and reducing DZC burden.
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Affiliation(s)
- Paula Medone
- Secretar�a de Educaci�n, Direcci�n de Desarrollo de la Gesti�n y la Calidad Educativa, Av. Gonzalo de Sandoval 760, Las V�boras, Colima, M�xico
| | - Carlos M Hernï Ndez-Suï Rez
- Facultad de Ciencias, Universidad de Colima, Bernal D�az del Castillo No. 340, Col. Villas San Sebasti�n, CP Colima, M�xico
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21
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Pinto PBA, Assis ML, Vallochi AL, Pacheco AR, Lima LM, Quaresma KRL, Pereira BAS, Costa SM, Alves AMB. T Cell Responses Induced by DNA Vaccines Based on the DENV2 E and NS1 Proteins in Mice: Importance in Protection and Immunodominant Epitope Identification. Front Immunol 2019; 10:1522. [PMID: 31333657 PMCID: PMC6617960 DOI: 10.3389/fimmu.2019.01522] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 06/18/2019] [Indexed: 01/04/2023] Open
Abstract
The importance of the cellular immune response against DENV has been increasingly highlighted in the past few years, in particular for vaccine development. We have previously constructed two plasmids, pE1D2, and pcTPANS1, encoding the envelope (E) ectodomain (domains I, II, and III) and the non-structural 1 (NS1) protein of dengue virus serotype 2 (DENV2), respectively. In the present work, we analyzed the induction of the cellular response in mice immunized with these DNA vaccines and identified the immunogenic peptides. Vaccinated BALB/c mice became protected against a lethal challenge of DENV2. Depletion of CD4+ cells in vaccinated animals almost completely abolished protection elicited by both vaccines. In contrast, a significant number of pE1D2- and pcTPANS1-immunized mice survived virus challenge after depletion of CD8+ cells, although some animals presented morbidity. To identify immunogenic peptides recognized by T cells, we stimulated splenocytes with overlapping peptide libraries covering the E and NS1 proteins and evaluated the production of IFN-γ by ELISPOT. We detected two and three immunodominant epitopes in the E and NS1 proteins, respectively, and four additional NS1-derived peptides after virus challenge. Characterization by intracellular cytokine staining (ICS) revealed that both CD4+ and CD8+ T cells were involved in IFN-γ and TNF-α production. The IFN-γ ICS confirmed reaction of almost all E-derived peptides before challenge and identified other epitopes after infection. All NS1-derived peptides were able to elicit IFN-γ production in CD4+ cells, while only a few peptides induced expression of this cytokine in CD8+ T lymphocytes. Interestingly, we observed an increase in the frequency of either CD4+ or CD8+ T cells producing TNF-α after immunization with the pE1D2 and challenge with DENV2, while lymphocytes from pcTPANS1-vaccinated animals maintained ordinary TNF-α production after virus infection. We also assessed the recognition of E and NS1 immunogenic peptides in C57BL/6 mice due to the difference in MHC haplotype expression. Two NS1-derived epitopes featured prominently in the IFN-γ response with cells from both animal strains. Overall, our results emphasize the importance of the T cell response involved in protection against dengue induced by E and NS1 based DNA vaccines.
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Affiliation(s)
- Paolla B. A. Pinto
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Maysa L. Assis
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Adriana L. Vallochi
- Laboratory of Immunopharmacology, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Agatha R. Pacheco
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Lauro M. Lima
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Kátia R. L. Quaresma
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Bernardo A. S. Pereira
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Simone M. Costa
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Ada M. B. Alves
- Laboratory of Biotechnology and Physiology of Viral Infections, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
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22
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Zandi K, Bassit L, Amblard F, Cox BD, Hassandarvish P, Moghaddam E, Yueh A, Libanio Rodrigues GO, Passos I, Costa VV, AbuBakar S, Zhou L, Kohler J, Teixeira MM, Schinazi RF. Nucleoside Analogs with Selective Antiviral Activity against Dengue Fever and Japanese Encephalitis Viruses. Antimicrob Agents Chemother 2019; 63:e00397-19. [PMID: 31061163 PMCID: PMC6591611 DOI: 10.1128/aac.00397-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 05/03/2019] [Indexed: 02/07/2023] Open
Abstract
Dengue virus (DENV) and Japanese encephalitis virus (JEV) are important arthropod-borne viruses from the Flaviviridae family. DENV is a global public health problem with significant social and economic impacts, especially in tropical and subtropical areas. JEV is a neurotropic arbovirus endemic to east and southeast Asia. There are no U.S. FDA-approved antiviral drugs available to treat or to prevent DENV and JEV infections, leaving nearly one-third of the world's population at risk for infection. Therefore, it is crucial to discover potent antiviral agents against these viruses. Nucleoside analogs, as a class, are widely used for the treatment of viral infections. In this study, we discovered nucleoside analogs that possess potent and selective anti-JEV and anti-DENV activities across all serotypes in cell-based assay systems. Both viruses were susceptible to sugar-substituted 2'-C-methyl analogs with either cytosine or 7-deaza-7-fluoro-adenine nucleobases. Mouse studies confirmed the anti-DENV activity of these nucleoside analogs. Molecular models were assembled for DENV serotype 2 (DENV-2) and JEV RNA-dependent RNA polymerase replication complexes bound to nucleotide inhibitors. These models show similarities between JEV and DENV-2, which recognize the same nucleotide inhibitors. Collectively, our findings provide promising compounds and a structural rationale for the development of direct-acting antiviral agents with dual activity against JEV and DENV infections.
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Affiliation(s)
- Keivan Zandi
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
- Tropical Infectious Disease Research and Education Center, Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Leda Bassit
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Franck Amblard
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Bryan D Cox
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Pouya Hassandarvish
- Tropical Infectious Disease Research and Education Center, Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ehsan Moghaddam
- Tropical Infectious Disease Research and Education Center, Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Andrew Yueh
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Taiwan, Republic of China
| | - Gisele Olinto Libanio Rodrigues
- Center for Research and Drug Development, Instituto de Ciencias Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Ingredy Passos
- Center for Research and Drug Development, Instituto de Ciencias Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Vivian V Costa
- Center for Research and Drug Development, Instituto de Ciencias Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Sazaly AbuBakar
- Tropical Infectious Disease Research and Education Center, Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Longhu Zhou
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - James Kohler
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Mauro M Teixeira
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
- Center for Research and Drug Development, Instituto de Ciencias Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Raymond F Schinazi
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
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23
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Yamanaka A, Konishi E. Key Amino Acid Substitution for Infection-Enhancing Activity-Free Designer Dengue Vaccines. iScience 2019; 13:125-137. [PMID: 30826727 PMCID: PMC6402262 DOI: 10.1016/j.isci.2019.02.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 02/11/2019] [Accepted: 02/13/2019] [Indexed: 11/17/2022] Open
Abstract
Dengue is a globally important disease caused by four serotypes of dengue virus. Dengue vaccine development has been hampered by antigenic cross-reactivity among serotypes, which potentially causes antibody-dependent enhancement of infection and disease severity. Here we found that a single amino acid substitution in the envelope protein at position 87 from aspartic acid to asparagine or at position 107 from leucine to phenylalanine is critical for suppressing the induction of infection-enhancing antibody in a mouse model. The site and type of amino acid substitution were determined via neutralization escape using an enhancing-activity-only monoclonal antibody that was engineered to reveal neutralizing activity. Mutated dengue type 1 DNA vaccines containing either or both amino acid substitutions induced neutralizing antibodies devoid of enhancing activity against all serotypes. The effect of substitution was further demonstrated using other serotypes and a tetravalent formulation. This finding may contribute to the development of infection-enhancing-activity-free dengue vaccines. Amino acids at E87 or E107 are critical for dengue-enhancing antibody induction Neutralization escape is useful for identifying the key types or sites of amino acids Each substitution can be applied to antigens of all four dengue serotypes A modified tetravalent DNA vaccine suppresses enhancing antibody induction in mice
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Affiliation(s)
- Atsushi Yamanaka
- BIKEN Endowed Department of Dengue Vaccine Development, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand; BIKEN Endowed Department of Dengue Vaccine Development, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
| | - Eiji Konishi
- BIKEN Endowed Department of Dengue Vaccine Development, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand; BIKEN Endowed Department of Dengue Vaccine Development, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan
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Lee JS, Mogasale V, Lim JK, Ly S, Lee KS, Sorn S, Andia E, Carabali M, Namkung S, Lim SK, Ridde V, Njenga SM, Yaro S, Yoon IK. A multi-country study of the economic burden of dengue fever based on patient-specific field surveys in Burkina Faso, Kenya, and Cambodia. PLoS Negl Trop Dis 2019; 13:e0007164. [PMID: 30817776 PMCID: PMC6394908 DOI: 10.1371/journal.pntd.0007164] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 01/16/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Dengue fever is a rapidly growing public health problem in many parts of the tropics and sub-tropics in the world. While there are existing studies on the economic burden of dengue fever in some of dengue-endemic countries, cost components are often not standardized, making cross-country comparisons challenging. Furthermore, no such studies have been available in Africa. METHODS/PRINCIPAL FINDINGS A patient-specific survey questionnaire was developed and applied in Burkina Faso, Kenya, and Cambodia in a standardized format. Multiple interviews were carried out in order to capture the entire cost incurred during the period of dengue illness. Both private (patient's out-of-pocket) and public (non-private) expenditure were accessed to understand how the economic burden of dengue is distributed between private and non-private payers. A substantial number of dengue-confirmed patients were identified in all three countries: 414 in Burkina Faso, 149 in Kenya, and 254 in Cambodia. The average cost of illness for dengue fever was $26 (95% CI $23-$29) and $134 (95% CI $119-$152) per inpatient in Burkina Faso and Cambodia, respectively. In the case of outpatients, the average economic burden per episode was $13 (95% CI $23-$29) in Burkina Faso and $23 (95% CI $19-$28) in Kenya. Compared to Cambodia, public contributions were trivial in Burkina Faso and Kenya, reflecting that a majority of medical costs had to be directly borne by patients in the two countries. CONCLUSIONS/SIGNIFICANCE The cost of illness for dengue fever is significant in the three countries. In particular, the current study sheds light on the potential economic burden of the disease in Burkina Faso and Kenya where existing evidence is sparse in the context of dengue fever, and underscores the need to achieve Universal Health Coverage. Given the availability of the current (CYD-TDV) and second-generation dengue vaccines in the near future, our study outcomes can be used to guide decision makers in setting health policy priorities.
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Affiliation(s)
| | | | | | - Sowath Ly
- Institute Pasteur, Phnom Penh, Cambodia
| | | | | | - Esther Andia
- Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
| | | | - Suk Namkung
- International Vaccine Institute, Seoul, South Korea
| | - Sl-Ki Lim
- International Vaccine Institute, Seoul, South Korea
| | - Valéry Ridde
- French Institute for Research on Sustainable Development (IRD), Universités Paris Sorbonne Cités, Paris, France
- University of Montreal Public Health Research Institute (IRSPUB), Montreal, Canada
| | | | | | - In-Kyu Yoon
- International Vaccine Institute, Seoul, South Korea
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25
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Usman HB, AlSahafi A, Abdulrashid O, Mandoura N, Al Sharif K, Ibrahim A, Ahmed L, Shamrani E, Shamia M. Effect of Health Education on Dengue Fever: A Comparison of Knowledge, Attitude, and Practices in Public and Private High School Children of Jeddah. Cureus 2018; 10:e3809. [PMID: 30868023 PMCID: PMC6402738 DOI: 10.7759/cureus.3809] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Objective More than half of the world’s population live in areas with a potential risk of acquiring dengue fever (DF). Health education interventions are effective, barring a language communication gap. The objective of this study was to estimate the effect of health education in the knowledge, attitude, and practices (KAP) towards DF control and prevention in public and private schools. Materials and methods We assessed the DF control and prevention strategy KAP of students of eight public and private schools in Jeddah, Saudi Arabia before the dengue health education intervention sessions (pre-I) and three months following the education intervention sessions (post-I) using the same closed-ended validated questionnaire. Schools and students were selected by a multistage stratified random sample method. Statistical analysis was done using the paired and independent T-test in IBM SPSS Statistics for Windows, Version 22.0 (IBM Corp., Armonk, NY). Results We found a significant mean difference in the overall knowledge (pre-I, 7.86 ± 2.61; post-I, 10.94 ± 2.35), attitude (pre-I, 5.16 ± 1.50; post-I 6.23 ± 1.30), and practice (pre-I, 2.96 ± 1.33; post-I, 3.94 ± 1.12) scores. Private schools scored better post-intervention scores in knowledge and practice compared to public schools in local and English language medium. Conclusions Health education programs are essential for DF prevention and management. Institutes whose populations consists of students with various language backgrounds should not be ignored. Bilingual educational sessions are important in such private institutes. Our results indicate additional emphasis is required on putting interventional knowledge into practice.
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Affiliation(s)
- Hassan B Usman
- Epidemiology and Public Health, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
| | - Abdullah AlSahafi
- Family Medicine, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
| | - Ola Abdulrashid
- Epidemiology and Public Health, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
| | - Najlaa Mandoura
- Epidemiology and Public Health, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
| | - Khalid Al Sharif
- Family Medicine, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
| | - Adel Ibrahim
- Epidemiology and Public Health, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
| | - Leena Ahmed
- Internal Medicine, Royal College of Surgeons, Dublin, IRL
| | - Etidal Shamrani
- Epidemiology and Public Health, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
| | - Mona Shamia
- Epidemiology and Public Health, Directorate of Health Affairs for Public Health Division, Jeddah, SAU
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Dans AL, Dans LF, Silvestre MAA, Halstead SB, Guyatt GH. Cause and consequence of loss in vaccine trust. Hum Vaccin Immunother 2018; 15:628-629. [PMID: 30513242 PMCID: PMC6988886 DOI: 10.1080/21645515.2018.1551674] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Accepted: 11/16/2018] [Indexed: 10/27/2022] Open
Affiliation(s)
| | | | | | - Scott B. Halstead
- Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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27
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Wiyeh AB, Cooper S, Nnaji CA, Wiysonge CS. Vaccine hesitancy ‘outbreaks’: using epidemiological modeling of the spread of ideas to understand the effects of vaccine related events on vaccine hesitancy. Expert Rev Vaccines 2018; 17:1063-1070. [DOI: 10.1080/14760584.2018.1549994] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Alison B. Wiyeh
- Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa
| | - Sara Cooper
- Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa
| | - Chukwudi A. Nnaji
- Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa
- School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa
| | - Charles S. Wiysonge
- Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa
- Division of Epidemiology and Biostatistics, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Stellenbosch, South Africa
- Division of Epidemiology and Biostatistics, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa
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Chen Y, Ong JHY, Rajarethinam J, Yap G, Ng LC, Cook AR. Neighbourhood level real-time forecasting of dengue cases in tropical urban Singapore. BMC Med 2018; 16:129. [PMID: 30078378 PMCID: PMC6091171 DOI: 10.1186/s12916-018-1108-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/21/2018] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Dengue, a vector-borne infectious disease caused by the dengue virus, has spread through tropical and subtropical regions of the world. All four serotypes of dengue viruses are endemic in the equatorial city state of Singapore, and frequent localised outbreaks occur, sometimes leading to national epidemics. Vector control remains the primary and most effective measure for dengue control and prevention. The objective of this study is to develop a novel framework for producing a spatio-temporal dengue forecast at a neighbourhood level spatial resolution that can be routinely used by Singapore's government agencies for planning of vector control for best efficiency. METHODS The forecasting algorithm uses a mixture of purely spatial, purely temporal and spatio-temporal data to derive dynamic risk maps for dengue transmission. LASSO-based regression was used for the prediction models and separate sub-models were constructed for each forecast window. Data were divided into training and testing sets for out-of-sample validation. Neighbourhoods were categorised as high or low risk based on the forecast number of cases within the cell. The predictive accuracy of the categorisation was measured. RESULTS Close concordance between the projections and the eventual incidence of dengue were observed. The average Matthew's correlation coefficient for a classification of the upper risk decile (operational capacity) is similar to the predictive performance at the optimal 30% cut-off. The quality of the spatial predictive algorithm as a classifier shows areas under the curve at all forecast windows being above 0.75 and above 0.80 within the next month. CONCLUSIONS Spatially resolved forecasts of geographically structured diseases like dengue can be obtained at a neighbourhood level in highly urban environments at a precision that is suitable for guiding control efforts. The same method can be adapted to other urban and even rural areas, with appropriate adjustment to the grid size and shape.
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Affiliation(s)
- Yirong Chen
- Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, 12 Science Drive 2, Singapore, 117549 Singapore
| | - Janet Hui Yi Ong
- Environmental Health Institute, 11 Biopolis Way, Singapore, 138667 Singapore
| | | | - Grace Yap
- Environmental Health Institute, 11 Biopolis Way, Singapore, 138667 Singapore
| | - Lee Ching Ng
- Environmental Health Institute, 11 Biopolis Way, Singapore, 138667 Singapore
| | - Alex R. Cook
- Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, 12 Science Drive 2, Singapore, 117549 Singapore
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Targeting vaccinations for the licensed dengue vaccine: Considerations for serosurvey design. PLoS One 2018; 13:e0199450. [PMID: 29944696 PMCID: PMC6019750 DOI: 10.1371/journal.pone.0199450] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 06/07/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The CYD-TDV vaccine was unusual in that the recommended target population for vaccination was originally defined not only by age, but also by transmission setting as defined by seroprevalence. WHO originally recommended countries consider vaccination against dengue with CYD-TDV vaccine in geographic settings only where prior infection with any dengue serotype, as measured by seroprevalence, was >170% in the target age group. Vaccine was not recommended in settings where seroprevalence was <50%. Test-and-vaccinate strategies suggested following new analysis by Sanofi will still require age-stratified seroprevalence surveys to optimise age-group targeting. Here we address considerations for serosurvey design in the context of vaccination program planning. METHODS To explore how the design of seroprevalence surveys affects estimates of transmission intensity, 100 age-specific seroprevalence surveys were simulated using a beta-binomial distribution and a simple catalytic model for different combinations of age-range, survey size, transmission setting, and test sensitivity/specificity. We then used a Metropolis-Hastings Markov Chain Monte-Carlo algorithm to estimate the force of infection from each simulated dataset. RESULTS Sampling from a wide age-range led to more accurate estimates than merely increasing sample size in a narrow age-range. This finding was consistent across all transmission settings. The optimum test sensitivity and specificity given an imperfect test differed by setting with high sensitivity being important in high transmission settings and high specificity important in low transmission settings. CONCLUSIONS When assessing vaccination suitability by seroprevalence surveys, countries should ensure an appropriate age-range is sampled, considering epidemiological evidence about the local burden of disease.
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Barrows NJ, Campos RK, Liao KC, Prasanth KR, Soto-Acosta R, Yeh SC, Schott-Lerner G, Pompon J, Sessions OM, Bradrick SS, Garcia-Blanco MA. Biochemistry and Molecular Biology of Flaviviruses. Chem Rev 2018; 118:4448-4482. [PMID: 29652486 DOI: 10.1021/acs.chemrev.7b00719] [Citation(s) in RCA: 189] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Flaviviruses, such as dengue, Japanese encephalitis, tick-borne encephalitis, West Nile, yellow fever, and Zika viruses, are critically important human pathogens that sicken a staggeringly high number of humans every year. Most of these pathogens are transmitted by mosquitos, and not surprisingly, as the earth warms and human populations grow and move, their geographic reach is increasing. Flaviviruses are simple RNA-protein machines that carry out protein synthesis, genome replication, and virion packaging in close association with cellular lipid membranes. In this review, we examine the molecular biology of flaviviruses touching on the structure and function of viral components and how these interact with host factors. The latter are functionally divided into pro-viral and antiviral factors, both of which, not surprisingly, include many RNA binding proteins. In the interface between the virus and the hosts we highlight the role of a noncoding RNA produced by flaviviruses to impair antiviral host immune responses. Throughout the review, we highlight areas of intense investigation, or a need for it, and potential targets and tools to consider in the important battle against pathogenic flaviviruses.
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Affiliation(s)
- Nicholas J Barrows
- Department of Biochemistry and Molecular Biology , University of Texas Medical Branch , Galveston , Texas 77555 , United States.,Department of Molecular Genetics and Microbiology , Duke University , Durham , North Carolina 27710 , United States
| | - Rafael K Campos
- Department of Biochemistry and Molecular Biology , University of Texas Medical Branch , Galveston , Texas 77555 , United States.,Department of Molecular Genetics and Microbiology , Duke University , Durham , North Carolina 27710 , United States
| | - Kuo-Chieh Liao
- Programme in Emerging Infectious Diseases , Duke-NUS Medical School , Singapore 169857 , Singapore
| | - K Reddisiva Prasanth
- Department of Biochemistry and Molecular Biology , University of Texas Medical Branch , Galveston , Texas 77555 , United States
| | - Ruben Soto-Acosta
- Department of Biochemistry and Molecular Biology , University of Texas Medical Branch , Galveston , Texas 77555 , United States
| | - Shih-Chia Yeh
- Programme in Emerging Infectious Diseases , Duke-NUS Medical School , Singapore 169857 , Singapore
| | - Geraldine Schott-Lerner
- Department of Biochemistry and Molecular Biology , University of Texas Medical Branch , Galveston , Texas 77555 , United States
| | - Julien Pompon
- Programme in Emerging Infectious Diseases , Duke-NUS Medical School , Singapore 169857 , Singapore.,MIVEGEC, IRD, CNRS, Université de Montpellier , Montpellier 34090 , France
| | - October M Sessions
- Programme in Emerging Infectious Diseases , Duke-NUS Medical School , Singapore 169857 , Singapore
| | - Shelton S Bradrick
- Department of Biochemistry and Molecular Biology , University of Texas Medical Branch , Galveston , Texas 77555 , United States
| | - Mariano A Garcia-Blanco
- Department of Biochemistry and Molecular Biology , University of Texas Medical Branch , Galveston , Texas 77555 , United States.,Programme in Emerging Infectious Diseases , Duke-NUS Medical School , Singapore 169857 , Singapore
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Dans AL, Dans LF, Lansang MAD, Silvestre MAA, Guyatt GH. Controversy and debate on dengue vaccine series-paper 3: final response to review of a licensed dengue vaccine: inappropriate subgroup analyses and selective reporting may cause harm in mass vaccination programs. J Clin Epidemiol 2018; 95:142. [PMID: 29306065 DOI: 10.1016/j.jclinepi.2017.12.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Antonio L Dans
- College of Medicine, University of the Philippines, Manila, Philippines
| | - Leonila F Dans
- College of Medicine, University of the Philippines, Manila, Philippines.
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