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Nissly RH, Lim L, Keller MR, Bird IM, Bhushan G, Misra S, Chothe SK, Sill MC, Kumar NV, Sivakumar AVN, Naik BR, Jayarao BM, Kuchipudi SV. The Susceptibility of Chickens to Zika Virus: A Comprehensive Study on Age-Dependent Infection Dynamics and Host Responses. Viruses 2024; 16:569. [PMID: 38675911 PMCID: PMC11054531 DOI: 10.3390/v16040569] [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: 03/03/2024] [Revised: 03/22/2024] [Accepted: 04/02/2024] [Indexed: 04/28/2024] Open
Abstract
Zika virus (ZIKV) remains a public health concern, with epidemics in endemic regions and sporadic outbreaks in new areas posing significant threats. Several mosquito-borne flaviviruses that can cause human illness, including West Nile, Usutu, and St. Louis encephalitis, have associations with birds. However, the susceptibility of chickens to ZIKV and their role in viral epidemiology is not currently known. We investigated the susceptibility of chickens to experimental ZIKV infection using chickens ranging from 1-day-old chicks to 6-week-old birds. ZIKV caused no clinical signs in chickens of all age groups tested. Viral RNA was detected in the blood and tissues during the first 5 days post-inoculation in 1-day and 4-day-old chicks inoculated with a high viral dose, but ZIKV was undetectable in 6-week-old birds at all timepoints. Minimal antibody responses were observed in 6-week-old birds, and while present in younger chicks, they waned by 28 days post-infection. Innate immune responses varied significantly between age groups. Robust type I interferon and inflammasome responses were measured in older chickens, while limited innate immune activation was observed in younger chicks. Signal transducer and activator of transcription 2 (STAT2) is a major driver of host restriction to ZIKV, and chicken STAT2 is distinct from human STAT2, potentially contributing to the observed resistance to ZIKV infection. The rapid clearance of the virus in older chickens coincided with an effective innate immune response, highlighting age-dependent susceptibility. Our study indicates that chickens are not susceptible to productive ZIKV infection and are unlikely to play a role in the ZIKV epidemiology.
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Affiliation(s)
- Ruth H. Nissly
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA; (R.H.N.); (L.L.); (M.R.K.); (I.M.B.); (G.B.); (B.M.J.)
| | - Levina Lim
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA; (R.H.N.); (L.L.); (M.R.K.); (I.M.B.); (G.B.); (B.M.J.)
- DermBiont, Inc., 451 D Street, Suite 908, Boston, MA 02210, USA
| | - Margo R. Keller
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA; (R.H.N.); (L.L.); (M.R.K.); (I.M.B.); (G.B.); (B.M.J.)
| | - Ian M. Bird
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA; (R.H.N.); (L.L.); (M.R.K.); (I.M.B.); (G.B.); (B.M.J.)
- Applied Biological Sciences Group, The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - Gitanjali Bhushan
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA; (R.H.N.); (L.L.); (M.R.K.); (I.M.B.); (G.B.); (B.M.J.)
- College of Medicine, Pennsylvania State University, Hershey, PA 17033, USA
| | - Sougat Misra
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, USA; (S.M.); (S.K.C.)
| | - Shubhada K. Chothe
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, USA; (S.M.); (S.K.C.)
| | - Miranda C. Sill
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA;
| | - Nagaram Vinod Kumar
- College of Veterinary Science, Sri Venkateswara Veterinary University, Tirupati 517 602, Andhra Pradesh, India; (N.V.K.); (A.V.N.S.); (B.R.N.)
| | - A. V. N. Sivakumar
- College of Veterinary Science, Sri Venkateswara Veterinary University, Tirupati 517 602, Andhra Pradesh, India; (N.V.K.); (A.V.N.S.); (B.R.N.)
| | - B. Rambabu Naik
- College of Veterinary Science, Sri Venkateswara Veterinary University, Tirupati 517 602, Andhra Pradesh, India; (N.V.K.); (A.V.N.S.); (B.R.N.)
| | - Bhushan M. Jayarao
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA; (R.H.N.); (L.L.); (M.R.K.); (I.M.B.); (G.B.); (B.M.J.)
| | - Suresh V. Kuchipudi
- Department of Infectious Diseases and Microbiology, University of Pittsburgh, Pittsburgh, PA 15261, USA; (S.M.); (S.K.C.)
- Center for Vaccine Research, University of Pittsburgh, Pittsburgh, PA 15261, USA
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Sabir AJ, Singh PP, Trus I, Le NPK, Karniychuk U. Asian Zika virus can acquire generic African-lineage mutations during in utero infection. Emerg Microbes Infect 2023; 12:2263592. [PMID: 37747060 PMCID: PMC10561574 DOI: 10.1080/22221751.2023.2263592] [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: 07/13/2023] [Accepted: 09/21/2023] [Indexed: 09/26/2023]
Abstract
The Zika virus 2015 epidemic showed an unusual phenotype for human flaviviruses, specifically fetal infection. We previously showed that in utero inoculation with the Asian Zika virus isolated from the human sample causes persistent infection in porcine fetuses. Here, we characterized the evolution of the Asian Zika virus in the fetal brain and placenta. Interestingly, the Asian Zika virus acquired generic African lineage K101R (A408G) and R1609 K (G4932A) mutations during in utero infection. Both African mutations were nonsynonymous and had a high frequency of nearly 100% in the fetal brain. Then, we synthetically generated the wild-type Asian variant and fetal brain-specific variant with generic African-lineage K101R and R1609 K mutations. In mosquito C6/36 cells, but not in human and pig cells, the fetal brain-specific variant showed higher virus loads compared to the Asian wild-type prototype. While in utero infection with both variants caused comparable virus loads in the placenta and amniotic fluids, fetuses injected with the fetal brain-specific variant had the trend to higher virus loads in lymph nodes. Also, introduced K101R and R1609 K mutations were stable and had high nearly 100% frequency at 28 days after in utero inoculation in both directly injected and trans-infected fetuses. These findings evoke concerns because Zika persists in pig herds and mosquitoes on farms in Mexico. It will be essential to identify how persistent in utero infection affects virus evolution and whether in utero-emerged Zika variants have the potential for shedding into the environment, more efficient transmission, and more aggressive infection phenotypes.
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Affiliation(s)
- Ahmad Jawad Sabir
- Vaccine and Infectious Disease Organization (VIDO), University of Saskatchewan, Saskatoon, Canada
| | - Prince Pal Singh
- School of Public Health, University of Saskatchewan, Saskatoon, Canada
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA
| | - Ivan Trus
- Dioscuri Centre for RNA-Protein Interactions in Human Health and Disease, International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Nguyen Phuong Khanh Le
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA
| | - Uladzimir Karniychuk
- School of Public Health, University of Saskatchewan, Saskatoon, Canada
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA
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3
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Lu AY, Gustin A, Newhouse D, Gale M. Viral Protein Accumulation of Zika Virus Variants Links with Regulation of Innate Immunity for Differential Control of Viral Replication, Spread, and Response to Interferon. J Virol 2023; 97:e0198222. [PMID: 37162358 PMCID: PMC10231147 DOI: 10.1128/jvi.01982-22] [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: 01/11/2023] [Accepted: 04/13/2023] [Indexed: 05/11/2023] Open
Abstract
Asian lineage Zika virus (ZIKV) strains emerged globally, causing outbreaks linked with critical clinical disease outcomes unless the virus is effectively restricted by host immunity. We have previously shown that retinoic acid-inducible gene-I (RIG-I) senses ZIKV to trigger innate immunity to direct interferon (IFN) production and antiviral responses that can control ZIKV infection. However, ZIKV proteins have been demonstrated to antagonize IFN. Here, we conducted in vitro analyses to assess how divergent prototypic ZIKV variants differ in virologic properties, innate immune regulation, and infection outcome. We comparatively assessed African lineage ZIKV/Dakar/1984/ArD41519 (ZIKV/Dakar) and Asian lineage ZIKV/Malaysia/1966/P6740 (ZIKV/Malaysia) in a human epithelial cell infection model. De novo viral sequence determination identified amino acid changes within the ZIKV/Dakar genome compared to ZIKV/Malaysia. Viral growth analyses revealed that ZIKV/Malaysia accumulated viral proteins and genome copies earlier and to higher levels than ZIKV/Dakar. Both ZIKV strains activated RIG-I/IFN regulatory factor (IRF3) and NF-κB pathways to induce inflammatory cytokine expression and types I and III IFNs. However, ZIKV/Malaysia, but not ZIKV/Dakar, potently blocked downstream IFN signaling. Remarkably, ZIKV/Dakar protein accumulation and genome replication were rescued in RIG-I knockout (KO) cells late in acute infection, resulting in ZIKV/Dakar-mediated blockade of IFN signaling. We found that RIG-I signaling specifically restricts viral protein accumulation late in acute infection where early accumulation of viral proteins in infected cells confers enhanced ability to limit IFN signaling, promoting viral replication and spread. Our results demonstrate that RIG-I-mediated innate immune signaling imparts restriction of ZIKV protein accumulation, which permits IFN signaling and antiviral actions controlling ZIKV infection. IMPORTANCE ZIKV isolates are classified under African or Asian lineages. Infection with emerging Asian lineage-derived ZIKV strains is associated with increased incidence of neurological symptoms that were not previously reported during infection with African or preemergent Asian lineage viruses. In this study, we utilized in vitro models to compare the virologic properties of and innate immune responses to two prototypic ZIKV strains from distinct lineages: African lineage ZIKV/Dakar and Asian lineage ZIKV/Malaysia. Compared to ZIKV/Dakar, ZIKV/Malaysia accumulates viral proteins earlier, replicates to higher levels, and robustly blocks IFN signaling during acute infection. Early accumulation of ZIKV/Malaysia NS5 protein confers enhanced ability to antagonize IFN signaling, dampening innate immune responses to promote viral spread. Our data identify the kinetics of viral protein accumulation as a major regulator of host innate immunity, influencing host-mediated control of ZIKV replication and spread. Importantly, these findings provide a novel framework for evaluating the virulence of emerging variants.
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Affiliation(s)
- Amy Y. Lu
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, Washington, USA
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - Andrew Gustin
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, Washington, USA
| | - Daniel Newhouse
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, Washington, USA
| | - Michael Gale
- Center for Innate Immunity and Immune Disease, Department of Immunology, University of Washington, Seattle, Washington, USA
- Department of Global Health, University of Washington, Seattle, Washington, USA
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Negi V, Kuhn RJ, Fekete DM. Exploring the Expression and Function of cTyro3, a Candidate Zika Virus Receptor, in the Embryonic Chicken Brain and Inner Ear. Viruses 2023; 15:247. [PMID: 36680287 PMCID: PMC9867072 DOI: 10.3390/v15010247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/05/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
The transmembrane protein Axl was proposed as an entry receptor for Zika virus (ZIKV) infection in vitro, but conflicting results from in vivo studies have made it difficult to establish Axl as a physiologically relevant ZIKV receptor. Both the functional redundancy of receptors and the experimental model used can lead to variable results. Therefore, it can be informative to explore alternative animal models to analyze ZIKV receptor candidates as an aid in discovering antivirals. This study used chicken embryos to examine the role of chicken Tyro3 (cTyro3), the equivalent of human Axl. Results show that endogenous cTyro3 mRNA expression overlaps with previously described hot spots of ZIKV infectivity in the brain and inner ear. We asked if ectopic expression or knockdown of cTyro3 influenced ZIKV infection in embryos. Tol2 vectors or replication-competent avian retroviruses were used in ovo to introduce full-length or truncated (presumed dominant-negative) cTyro3, respectively, into the neural tube on embryonic day two (E2). ZIKV was delivered to the brain 24 h later. cTyro3 manipulations did not alter ZIKV infection or cell death in the E5/E6 brain. Moreover, delivery of truncated cTyro3 variants to the E3 otocyst had no effect on inner ear formation on E6 or E10.
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Affiliation(s)
| | | | - Donna M. Fekete
- Department of Biological Sciences, Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47906, USA
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5
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Jung HG, Cho H, Kim M, Jung H, Bak Y, Lee SY, Seo HY, Son YM, Woo H, Yoon G, Kim SJ, Oh JW. Influence of Zika virus 3'-end sequence and nonstructural protein evolution on the viral replication competence and virulence. Emerg Microbes Infect 2022; 11:2447-2465. [PMID: 36149812 PMCID: PMC9621255 DOI: 10.1080/22221751.2022.2128433] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 09/20/2022] [Indexed: 11/09/2022]
Abstract
Zika virus (ZIKV) has been circulating in human networks over 70 years since its first appearance in Africa, yet little is known about whether the viral 3'-terminal sequence and nonstructural (NS) protein diverged genetically from ancient ZIKV have different effects on viral replication and virulence in currently prevailing Asian lineage ZIKV. Here we show, by a reverse genetics approach using an infectious cDNA clone for a consensus sequence (Con1) of ZIKV, which represents Asian ZIKV strains, and another clone derived from the MR766 strain isolated in Uganda, Africa in 1947, that the 3'-end sequence -UUUCU-3' homogeneously present in MR766 genome and the -GUCU-3' sequence strictly conserved in Asian ZIKV isolates are functionally equivalent in viral replication and gene expression. By gene swapping experiments using the two infectious cDNA clones, we show that the NS1-5 proteins of MR766 enhance replication competence of ZIKV Con1. The Con1, which was less virulent than MR766, acquired severe bilateral hindlimb paralysis when its NS1-5 genes were replaced by the counterparts of MR766 in type I interferon receptor (IFNAR1)-deficient A129 mice. Moreover, MR766 NS5 RNA-dependent RNA polymerase (RdRp) alone also rendered the Con1 virulent, despite there being no difference in RdRp activity between MR766 and Con1 NS5 proteins. By contrast, the Con1 derivatives expressing MR766 Nsps, like Con1, did not develop severe disease in wild-type mice treated with an IFNAR1 blocking antibody. Together, our findings uncover an unprecedented role for ZIKV NS proteins in determining viral pathogenicity in immunocompromised hosts.
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Affiliation(s)
- Hae-Gwang Jung
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Hee Cho
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Minwoo Kim
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Haewon Jung
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Yeonju Bak
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Se-Young Lee
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Han Young Seo
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Yu-Min Son
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Hawon Woo
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Gone Yoon
- Department of Biotechnology, Yonsei University, Seoul, South Korea
| | - Seong-Jun Kim
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon, South Korea
| | - Jong-Won Oh
- Department of Biotechnology, Yonsei University, Seoul, South Korea
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6
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Nascimento JM, Gouvêa-Junqueira D, Zuccoli GS, Pedrosa CDSG, Brandão-Teles C, Crunfli F, Antunes ASLM, Cassoli JS, Karmirian K, Salerno JA, de Souza GF, Muraro SP, Proenca-Módena JL, Higa LM, Tanuri A, Garcez PP, Rehen SK, Martins-de-Souza D. Zika Virus Strains and Dengue Virus Induce Distinct Proteomic Changes in Neural Stem Cells and Neurospheres. Mol Neurobiol 2022; 59:5549-5563. [PMID: 35732867 DOI: 10.1007/s12035-022-02922-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 06/05/2022] [Indexed: 11/30/2022]
Abstract
Brain abnormalities and congenital malformations have been linked to the circulating strain of Zika virus (ZIKV) in Brazil since 2016 during the microcephaly outbreak; however, the molecular mechanisms behind several of these alterations and differential viral molecular targets have not been fully elucidated. Here we explore the proteomic alterations induced by ZIKV by comparing the Brazilian (Br ZIKV) and the African (MR766) viral strains, in addition to comparing them to the molecular responses to the Dengue virus type 2 (DENV). Neural stem cells (NSCs) derived from induced pluripotent stem (iPSCs) were cultured both as monolayers and in suspension (resulting in neurospheres), which were then infected with ZIKV (Br ZIKV or ZIKV MR766) or DENV to assess alterations within neural cells. Large-scale proteomic analyses allowed the comparison not only between viral strains but also regarding the two- and three-dimensional cellular models of neural cells derived from iPSCs, and the effects on their interaction. Altered pathways and biological processes were observed related to cell death, cell cycle dysregulation, and neurogenesis. These results reinforce already published data and provide further information regarding the biological alterations induced by ZIKV and DENV in neural cells.
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Affiliation(s)
- Juliana Minardi Nascimento
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil.,D'Or Institute for Research and Education (IDOR), Rua Diniz Cordeiro, 30, Rio de Janeiro, RJ, 22281-100, Brazil.,Department of Biosciences, Federal University of São Paulo, Santos, Brazil
| | - Danielle Gouvêa-Junqueira
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil
| | - Giuliana S Zuccoli
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil
| | | | - Caroline Brandão-Teles
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil
| | - Fernanda Crunfli
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil
| | - André S L M Antunes
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil
| | - Juliana S Cassoli
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil.,Institute of Biological Sciences, Federal University of Pará (UFPA), Belém, Brazil
| | - Karina Karmirian
- D'Or Institute for Research and Education (IDOR), Rua Diniz Cordeiro, 30, Rio de Janeiro, RJ, 22281-100, Brazil
| | - José Alexandre Salerno
- D'Or Institute for Research and Education (IDOR), Rua Diniz Cordeiro, 30, Rio de Janeiro, RJ, 22281-100, Brazil
| | - Gabriela Fabiano de Souza
- Laboratory of Emerging Viruses, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Stéfanie Primon Muraro
- Laboratory of Emerging Viruses, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Jose Luiz Proenca-Módena
- Laboratory of Emerging Viruses, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Luiza M Higa
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Amilcar Tanuri
- Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Patricia P Garcez
- D'Or Institute for Research and Education (IDOR), Rua Diniz Cordeiro, 30, Rio de Janeiro, RJ, 22281-100, Brazil.,Institute of Biomedical Sciences, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Stevens K Rehen
- D'Or Institute for Research and Education (IDOR), Rua Diniz Cordeiro, 30, Rio de Janeiro, RJ, 22281-100, Brazil. .,Institute of Biology, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
| | - Daniel Martins-de-Souza
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas, Rua Monteiro Lobato, Campinas, SP, 255, 13083-862, Brazil. .,D'Or Institute for Research and Education (IDOR), Rua Diniz Cordeiro, 30, Rio de Janeiro, RJ, 22281-100, Brazil. .,Experimental Medicine Research Cluster (EMRC), University of Campinas, Campinas, Brazil. .,Instituto Nacional de Biomarcadores Em Neuropsiquiatria (INBION), Conselho Nacional de Desenvolvimento Científico E Tecnológico, São Paulo, Brazil.
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Abstract
Zika virus is a mosquito-borne flavivirus known to cause severe birth defects and neuroimmunological disorders. We have previously demonstrated that mosquito transmission of Zika virus decreases with temperature. While transmission was optimized at 29°C, it was limited at cool temperatures (<22°C) due to poor virus establishment in the mosquitoes. Temperature is one of the strongest drivers of vector-borne disease transmission due to its profound effect on ectothermic mosquito vectors, viruses, and their interaction. Although there is substantial evidence of temperature effects on arbovirus replication and dissemination inside mosquitoes, little is known about whether temperature affects virus replication directly or indirectly through mosquito physiology. In order to determine the mechanisms behind temperature-induced changes in Zika virus transmission potential, we investigated different steps of the virus replication cycle in mosquito cells (C6/36) at optimal (28°C) and cool (20°C) temperatures. We found that the cool temperature did not alter Zika virus entry or translation, but it affected genome replication and reduced the amount of double-stranded RNA replication intermediates. If replication complexes were first formed at 28°C and the cells were subsequently shifted to 20°C, the late steps in the virus replication cycle were efficiently completed. These data suggest that cool temperature decreases the efficiency of Zika virus genome replication in mosquito cells. This phenotype was observed in the Asian lineage of Zika virus, while the African lineage Zika virus was less restricted at 20°C. IMPORTANCE With half of the human population at risk, arboviral diseases represent a substantial global health burden. Zika virus, previously known to cause sporadic infections in humans, emerged in the Americas in 2015 and quickly spread worldwide. There was an urgent need to better understand the disease pathogenesis and develop therapeutics and vaccines, as well as to understand, predict, and control virus transmission. In order to efficiently predict the seasonality and geography for Zika virus transmission, we need a deeper understanding of the host-pathogen interactions and how they can be altered by environmental factors such as temperature. Identifying the step in the virus replication cycle that is inhibited under cool conditions can have implications in modeling the temperature suitability for arbovirus transmission as global environmental patterns change. Understanding the link between pathogen replication and environmental conditions can potentially be exploited to develop new vector control strategies in the future.
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8
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King EL, Irigoyen N. Zika Virus and Neuropathogenesis: The Unanswered Question of Which Strain Is More Prone to Causing Microcephaly and Other Neurological Defects. Front Cell Neurosci 2021; 15:695106. [PMID: 34658789 PMCID: PMC8514627 DOI: 10.3389/fncel.2021.695106] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 08/25/2021] [Indexed: 12/14/2022] Open
Abstract
Despite being perceived to be a relatively innocuous pathogen during its circulation in Africa in the 20th century, consequent outbreaks in French Polynesia and Latin America revealed the Zika virus (ZIKV) to be capable of causing severe neurological defects. Foetuses infected with the virus during pregnancy developed a range of pathologies including microcephaly, cerebral calcifications and macular scarring. These are now collectively known as Congenital Zika syndrome (CZS). It has been established that the neuropathogenesis of ZIKV results from infection of neural progenitor cells in the developing cerebral cortex. Following this, two main hypotheses have emerged: the virus causes either apoptosis or premature differentiation of neural progenitor cells, reducing the final number of mature neurons in the cerebral cortex. This review describes the cellular processes which could potentially cause virus induced apoptosis or premature differentiation, leading to speculation that a combination of the two may be responsible for the pathologies associated with ZIKV. The review also discusses which specific lineages of the ZIKV can employ these mechanisms. It has been unclear in the past whether the virus evolved its neurotropic capability following circulation in Africa, or if the virus has always caused microcephaly but public health surveillance in Africa had failed to detect it. Understanding the true neuropathogenesis of ZIKV is key to being prepared for further outbreaks in the future, and it will also provide insight into how neurotropic viruses can cause profound and life-long neurological defects.
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Affiliation(s)
- Emily Louise King
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Nerea Irigoyen
- Division of Virology, Department of Pathology, University of Cambridge, Cambridge, United Kingdom
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9
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de Matos SMS, Hennigen AF, Wachholz GE, Rengel BD, Schuler-Faccini L, Roehe PM, Varela APM, Fraga LR. Possible Emergence of Zika Virus of African Lineage in Brazil and the Risk for New Outbreaks. Front Cell Infect Microbiol 2021; 11:680025. [PMID: 34368011 PMCID: PMC8342935 DOI: 10.3389/fcimb.2021.680025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/25/2021] [Indexed: 12/15/2022] Open
Affiliation(s)
- Sophia Martins Simon de Matos
- Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - André Ferreira Hennigen
- Laboratory of Virology, Department of Microbiology, Immunology and Parasitology, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Gabriela Elis Wachholz
- Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Postgraduate Program in Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Bruna Duarte Rengel
- Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Postgraduate Program in Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Lavinia Schuler-Faccini
- Postgraduate Program in Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Paulo Michel Roehe
- Laboratory of Virology, Department of Microbiology, Immunology and Parasitology, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Ana Paula Muterle Varela
- Postgraduate Program in Bioscience, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
| | - Lucas Rosa Fraga
- Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Department of Morphological Sciences, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Medicine: Medical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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10
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Wachholz GE, Rengel BD, Vargesson N, Fraga LR. From the Farm to the Lab: How Chicken Embryos Contribute to the Field of Teratology. Front Genet 2021; 12:666726. [PMID: 34367238 PMCID: PMC8339958 DOI: 10.3389/fgene.2021.666726] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/11/2021] [Indexed: 02/04/2023] Open
Abstract
Congenital anomalies and its causes, particularly, by external factors are the aim of the field called teratology. The external factors studied by teratology are known as teratogens and can be biological or environmental factors for example, chemicals, medications, recreational drugs, environmental pollutants, physical agents (e.g., X-rays and maternal hyperthermia) and maternal metabolic conditions. Proving the teratogenicity of a factor is a difficult task requiring epidemiology studies as well as experimental teratology evidence from the use of animal models, one of which is the chicken embryo. This model in particular has the advantage of being able to follow development live and in vivo, with rapid development hatching around 21 days, is cheap and easy to manipulate and to observe development. All this allows the chicken embryo to be used in drug screening studies, teratogenic evaluation and studies of mechanisms of teratogenicity. The chicken embryo shares morphological, biochemical and genetic similarities with humans as well as mammalian species, making them ideal to ascertain the actions of teratogens, as well as screen drugs to test for their safety. Pre-clinical trials for new drugs are carried out in rodents and rabbits, however, chicken embryos have been used to screen new compounds or analogs of thalidomide as well as to investigate how some drugs can lead to congenital malformations. Indeed, the chicken embryo has proved valuable in understanding how many congenital anomalies, seen in humans, arise following teratogen exposure. The aim of this review is to highlight the role of the chicken embryo as an experimental model for studies in teratology, exploring its use in drug screening studies, phenotypic evaluation and studies of teratogenic mechanisms of action. Here, we discuss many known teratogens, that have been evaluated using the chicken embryo model including some medicines, such as, thalidomide, valproic acid; recreational drugs including alcohol; environmental influences, such as viruses, specifically ZIKV, which is a newly discovered human teratogen. In addition, we discuss how the chicken embryo has provided insight on the mechanisms of teratogenesis of many compounds and also how this impact on drug safety.
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Affiliation(s)
- Gabriela Elis Wachholz
- Postgraduate Program of Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Bruna Duarte Rengel
- Postgraduate Program of Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Neil Vargesson
- School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Lucas Rosa Fraga
- Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Department of Morphological Sciences, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Postgraduate Program in Medicine: Medical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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11
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Shi H, Yin J. Kinetics of Asian and African Zika virus lineages over single-cycle and multi-cycle growth in culture: Gene expression, cell killing, virus production, and mathematical modeling. Biotechnol Bioeng 2021; 118:4231-4245. [PMID: 34270089 DOI: 10.1002/bit.27892] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/22/2021] [Accepted: 07/01/2021] [Indexed: 11/07/2022]
Abstract
Since 2014, an Asian lineage of Zika virus has caused outbreaks, and it has been associated with neurological disorders in adults and congenital defects in newborns. The resulting threat of the Zika virus to human health has prompted the development of new vaccines, which have yet to be approved for human use. Vaccines based on the attenuated or chemically inactivated virus will require large-scale production of the intact virus to meet potential global demands. Intact viruses are produced by infecting cultures of susceptible cells, a dynamic process that spans from hours to days and has yet to be optimized. Here, we infected Vero cells adhesively cultured in well-plates with two Zika virus strains: a recently isolated strain from the Asian lineage, and a cell-culture-adapted strain from the African lineage. At different time points post-infection, virus particles in the supernatant were quantified; further, microscopy images were used to quantify cell density and the proportion of cells expressing viral protein. These measurements were performed across multiple replicate samples of one-step infections every four hours over 60 h and for multi-step infections every four to 24 h over 144 h, generating a rich data set. For each set of data, mathematical models were developed to estimate parameters associated with cell infection and virus production. The African-lineage strain was found to produce a 14-fold higher yield than the Asian-lineage strain in one-step growth and a sevenfold higher titer in multi-step growth, suggesting a benefit of cell-culture adaptation for developing a vaccine strain. We found that image-based measurements were critical for discriminating among different models, and different parameters for the two strains could account for the experimentally observed differences. An exponential-distributed delay model performed best in accounting for multi-step infection of the Asian strain, and it highlighted the significant sensitivity of virus titer to the rate of viral degradation, with implications for optimization of vaccine production. More broadly, this study highlights how image-based measurements can contribute to the discrimination of virus-culture models for the optimal production of inactivated and attenuated whole-virus vaccines.
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Affiliation(s)
- Huicheng Shi
- Department of Chemical and Biological Engineering, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - John Yin
- Department of Chemical and Biological Engineering, Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA
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12
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Aubry F, Jacobs S, Darmuzey M, Lequime S, Delang L, Fontaine A, Jupatanakul N, Miot EF, Dabo S, Manet C, Montagutelli X, Baidaliuk A, Gámbaro F, Simon-Lorière E, Gilsoul M, Romero-Vivas CM, Cao-Lormeau VM, Jarman RG, Diagne CT, Faye O, Faye O, Sall AA, Neyts J, Nguyen L, Kaptein SJF, Lambrechts L. Recent African strains of Zika virus display higher transmissibility and fetal pathogenicity than Asian strains. Nat Commun 2021; 12:916. [PMID: 33568638 PMCID: PMC7876148 DOI: 10.1038/s41467-021-21199-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 01/16/2021] [Indexed: 11/09/2022] Open
Abstract
The global emergence of Zika virus (ZIKV) revealed the unprecedented ability for a mosquito-borne virus to cause congenital birth defects. A puzzling aspect of ZIKV emergence is that all human outbreaks and birth defects to date have been exclusively associated with the Asian ZIKV lineage, despite a growing body of laboratory evidence pointing towards higher transmissibility and pathogenicity of the African ZIKV lineage. Whether this apparent paradox reflects the use of relatively old African ZIKV strains in most laboratory studies is unclear. Here, we experimentally compare seven low-passage ZIKV strains representing the recently circulating viral genetic diversity. We find that recent African ZIKV strains display higher transmissibility in mosquitoes and higher lethality in both adult and fetal mice than their Asian counterparts. We emphasize the high epidemic potential of African ZIKV strains and suggest that they could more easily go unnoticed by public health surveillance systems than Asian strains due to their propensity to cause fetal loss rather than birth defects. Here, the authors compare seven low passage Zika virus (ZIKV) strains representing the recently circulating viral genetic diversity of African and Asian strains and find that African ZIKV strains have higher transmissibility in mosquitoes and higher lethality in both adult and fetal mice.
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Affiliation(s)
- Fabien Aubry
- Insect-Virus Interactions Unit, Institut Pasteur, UMR2000, CNRS, Paris, France
| | - Sofie Jacobs
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium
| | - Maïlis Darmuzey
- GIGA-Stem Cells/GIGA-Neurosciences, Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), C.H.U. Sart Tilman, University of Liège, Liège, Belgium
| | - Sebastian Lequime
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Clinical and Epidemiological Virology, Leuven, Belgium.,Cluster of Microbial Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - Leen Delang
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium
| | - Albin Fontaine
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées (IRBA), Marseille, France.,IRD, SSA, AP-HM, UMR Vecteurs-Infections Tropicales et Méditerranéennes (VITROME), Aix Marseille University, Marseille, France.,IHU Méditerranée Infection, Marseille, France
| | - Natapong Jupatanakul
- Insect-Virus Interactions Unit, Institut Pasteur, UMR2000, CNRS, Paris, France.,National Center for Genetic Engineering and Biotechnology (BIOTEC), Pathum Thani, Thailand
| | - Elliott F Miot
- Insect-Virus Interactions Unit, Institut Pasteur, UMR2000, CNRS, Paris, France
| | - Stéphanie Dabo
- Insect-Virus Interactions Unit, Institut Pasteur, UMR2000, CNRS, Paris, France
| | - Caroline Manet
- Mouse Genetics Laboratory, Institut Pasteur, Paris, France
| | | | - Artem Baidaliuk
- Insect-Virus Interactions Unit, Institut Pasteur, UMR2000, CNRS, Paris, France.,Evolutionary Genomics of RNA Viruses Group, Institut Pasteur, Paris, France
| | - Fabiana Gámbaro
- Evolutionary Genomics of RNA Viruses Group, Institut Pasteur, Paris, France
| | | | - Maxime Gilsoul
- GIGA-Stem Cells/GIGA-Neurosciences, Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), C.H.U. Sart Tilman, University of Liège, Liège, Belgium
| | - Claudia M Romero-Vivas
- Laboratorio de Enfermedades Tropicales, Departamento de Medicina, Fundación Universidad del Norte, Barranquilla, Colombia
| | | | - Richard G Jarman
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Cheikh T Diagne
- Arbovirus and Viral Hemorrhagic Fevers Unit, Institut Pasteur Dakar, Dakar, Senegal
| | - Oumar Faye
- Arbovirus and Viral Hemorrhagic Fevers Unit, Institut Pasteur Dakar, Dakar, Senegal
| | - Ousmane Faye
- Arbovirus and Viral Hemorrhagic Fevers Unit, Institut Pasteur Dakar, Dakar, Senegal
| | - Amadou A Sall
- Arbovirus and Viral Hemorrhagic Fevers Unit, Institut Pasteur Dakar, Dakar, Senegal
| | - Johan Neyts
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium
| | - Laurent Nguyen
- GIGA-Stem Cells/GIGA-Neurosciences, Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), C.H.U. Sart Tilman, University of Liège, Liège, Belgium
| | - Suzanne J F Kaptein
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, Leuven, Belgium.
| | - Louis Lambrechts
- Insect-Virus Interactions Unit, Institut Pasteur, UMR2000, CNRS, Paris, France.
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13
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Spencer Clinton JL, Tran LL, Vogt MB, Rowley DR, Kimata JT, Rico-Hesse R. IP-10 and CXCR3 signaling inhibit Zika virus replication in human prostate cells. PLoS One 2020; 15:e0244587. [PMID: 33378361 PMCID: PMC7773246 DOI: 10.1371/journal.pone.0244587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 12/12/2020] [Indexed: 11/18/2022] Open
Abstract
Our previous studies have shown that Zika virus (ZIKV) replicates in human prostate cells, suggesting that the prostate may serve as a long-term reservoir for virus transmission. Here, we demonstrated that the innate immune responses generated to three distinct ZIKV strains (all isolated from human serum) were significantly different and dependent on their passage history (in mosquito, monkey, or human cells). In addition, some of these phenotypic differences were reduced by a single additional cell culture passage, suggesting that viruses that have been passaged more than 3 times from the patient sample will no longer reflect natural phenotypes. Two of the ZIKV strains analyzed induced high levels of the IP-10 chemokine and IFNγ in human prostate epithelial and stromal mesenchymal stem cells. To further understand the importance of these innate responses on ZIKV replication, we measured the effects of IP-10 and its downstream receptor, CXCR3, on RNA and virus production in prostate cells. Treatment with IP-10, CXCR3 agonist, or CXCR3 antagonist significantly altered ZIKV viral gene expression, depending on their passage in cells of relevant hosts (mosquito or human). We detected differences in gene expression of two primary CXCR3 isoforms (CXCR3-A and CXCR3-B) on the two cell types, possibly explaining differences in viral output. Lastly, we examined the effects of IP-10, agonist, or antagonist on cell death and proliferation under physiologically relevant infection rates, and detected no significant differences. Although we did not measure protein expression directly, our results indicate that CXCR3 signaling may be a target for therapeutics, to ultimately stop sexual transmission of this virus.
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Affiliation(s)
- Jennifer L. Spencer Clinton
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Linda L. Tran
- Integrative Molecular and Biomedical Sciences Graduate Program, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Megan B. Vogt
- Integrative Molecular and Biomedical Sciences Graduate Program, Baylor College of Medicine, Houston, Texas, United States of America
| | - David R. Rowley
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jason T. Kimata
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Rebecca Rico-Hesse
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
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14
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Animal models of congenital zika syndrome provide mechanistic insight into viral pathogenesis during pregnancy. PLoS Negl Trop Dis 2020; 14:e0008707. [PMID: 33091001 PMCID: PMC7580937 DOI: 10.1371/journal.pntd.0008707] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In utero Zika virus (ZIKV; family Flaviviridae) infection causes a distinct pattern of birth defects and disabilities in the developing fetus and neonate that has been termed congenital zika syndrome (CZS). Over 8,000 children were affected by the 2016 to 2017 ZIKV outbreak in the Americas, many of whom developed CZS as a result of in utero exposure. To date, there is no consensus about how ZIKV causes CZS; animal models, however, are providing mechanistic insights. Using nonhuman primates, immunocompromised mice, immunocompetent mice, and other animal models (e.g., pigs, sheep, guinea pigs, and hamsters), studies are showing that maternal immunological responses, placental infection and inflammation, as well as viral genetic factors play significant roles in predicting the downstream consequences of in utero ZIKV infection on the development of CZS in offspring. There are thousands of children suffering from adverse consequences of CZS. Therefore, the animal models developed to study ZIKV-induced adverse outcomes in offspring could provide mechanistic insights into how other viruses, including influenza and hepatitis C viruses, impact placental viability and fetal growth to cause long-term adverse outcomes in an effort to identify therapeutic treatments.
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15
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Wachholz GE, Varela APM, Teixeira TF, de Matos SMS, Rigon da Luz Soster P, Vianna FSL, de Souza DOG, Roehe PM, Schuler-Faccini L, Fraga LR. Zika virus-induced brain malformations in chicken embryos. Birth Defects Res 2020; 113:22-31. [PMID: 33009728 DOI: 10.1002/bdr2.1813] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/07/2020] [Accepted: 09/18/2020] [Indexed: 11/12/2022]
Abstract
BACKGROUND Zika virus (ZIKV) was confirmed to be related to microcephaly in 2016. However, there is still a need for understanding the embryonic morphological changes induced by ZIKV and when they occur. Here, chicken embryos were chosen as experimental model of ZIKV to evaluate virus-associated morphological alterations that might take place during embryonic development. METHODS A screening with different viral doses was conducted in embryos at HH Stage 10-12 (E1.5) as well as a follow up of the first 5 days postinfection (dpi) was performed to observe the main morphologic changes post ZIKV infection. RESULTS ZIKV exposed embryos presented a higher prevalence of mortality and defects such as brain malformation when compared to controls. Moreover, we observed that the phenotypes become more evident at 4dpi, when the viral load quantification reaches a peak. CONCLUSIONS We found that ZIKV exposed embryos presented a high prevalence of mortality and central nervous system (CNS) abnormalities in a dose-dependent manner. The phenotype was more evident 4 days postinfection, when the viral load quantification reached a peak.
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Affiliation(s)
- Gabriela Elis Wachholz
- Postgraduate Program in Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Ana Paula Muterle Varela
- Postgraduate Program in Biosciences, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
| | - Thais Fumaco Teixeira
- Department of Microbiology, Immunology and Parasitology, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Sophia Martins Simon de Matos
- Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Paula Rigon da Luz Soster
- Department of Morphological Sciences, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Fernanda Sales Luiz Vianna
- Postgraduate Program in Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Diogo Onofre Gomes de Souza
- Postgraduate Program in Biochemistry, Departamento f Biochemistry, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Paulo Michel Roehe
- Department of Microbiology, Immunology and Parasitology, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Lavínia Schuler-Faccini
- Postgraduate Program in Genetics and Molecular Biology, Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Lucas Rosa Fraga
- Teratogen Information Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Laboratory of Genomic Medicine, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.,Department of Morphological Sciences, Institute of Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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16
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Ferreira PG, Tesla B, Horácio ECA, Nahum LA, Brindley MA, de Oliveira Mendes TA, Murdock CC. Temperature Dramatically Shapes Mosquito Gene Expression With Consequences for Mosquito-Zika Virus Interactions. Front Microbiol 2020; 11:901. [PMID: 32595607 PMCID: PMC7303344 DOI: 10.3389/fmicb.2020.00901] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 04/16/2020] [Indexed: 12/20/2022] Open
Abstract
Vector-borne flaviviruses are emerging threats to human health. For successful transmission, the virus needs to efficiently enter mosquito cells and replicate within and escape several tissue barriers while mosquitoes elicit major transcriptional responses to flavivirus infection. This process will be affected not only by the specific mosquito-pathogen pairing but also by variation in key environmental variables such as temperature. Thus far, few studies have examined the molecular responses triggered by temperature and how these responses modify infection outcomes, despite substantial evidence showing strong relationships between temperature and transmission in a diversity of systems. To define the host transcriptional changes associated with temperature variation during the early infection process, we compared the transcriptome of mosquito midgut samples from mosquitoes exposed to Zika virus (ZIKV) and non-exposed mosquitoes housed at three different temperatures (20, 28, and 36°C). While the high-temperature samples did not show significant changes from those with standard rearing conditions (28°C) 48 h post-exposure, the transcriptome profile of mosquitoes housed at 20°C was dramatically different. The expression of genes most altered by the cooler temperature involved aspects of blood-meal digestion, ROS metabolism, and mosquito innate immunity. Further, we did not find significant differences in the viral RNA copy number between 24 and 48 h post-exposure at 20°C, suggesting that ZIKV replication is limited by cold-induced changes to the mosquito midgut environment. In ZIKV-exposed mosquitoes, vitellogenin, a lipid carrier protein, was most up-regulated at 20°C. Our results provide a deeper understanding of the temperature-triggered transcriptional changes in Aedes aegypti and can be used to further define the molecular mechanisms driven by environmental temperature variation.
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Affiliation(s)
| | - Blanka Tesla
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Elvira Cynthia Alves Horácio
- René Rachou Institute, Oswaldo Cruz Foundation, Belo Horizonte, Brazil.,Department of Genetics, Ecology and Evolution, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Laila Alves Nahum
- René Rachou Institute, Oswaldo Cruz Foundation, Belo Horizonte, Brazil.,Department of Genetics, Ecology and Evolution, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil.,Promove College of Technology, Belo Horizonte, Brazil
| | - Melinda Ann Brindley
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States.,Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, United States.,Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
| | | | - Courtney Cuinn Murdock
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States.,Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States.,Odum School of Ecology, University of Georgia, Athens, GA, United States.,Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, United States.,Center for Emerging and Global Tropical Diseases, University of Georgia, Athens, GA, United States.,River Basin Center, University of Georgia, Athens, GA, United States.,Department of Entomology, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, United States
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17
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Modelling Degradation and Replication Kinetics of the Zika Virus In Vitro Infection. Viruses 2020; 12:v12050547. [PMID: 32429277 PMCID: PMC7290367 DOI: 10.3390/v12050547] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/16/2020] [Accepted: 05/11/2020] [Indexed: 12/17/2022] Open
Abstract
Mathematical models of in vitro viral kinetics help us understand and quantify the main determinants underlying the virus–host cell interactions. We aimed to provide a numerical characterization of the Zika virus (ZIKV) in vitro infection kinetics, an arthropod-borne emerging virus that has gained public recognition due to its association with microcephaly in newborns. The mathematical model of in vitro viral infection typically assumes that degradation of extracellular infectious virus proceeds in an exponential manner, that is, each viral particle has the same probability of losing infectivity at any given time. We incubated ZIKV stock in the cell culture media and sampled with high frequency for quantification over the course of 96 h. The data showed a delay in the virus degradation in the first 24 h followed by a decline, which could not be captured by the model with exponentially distributed decay time of infectious virus. Thus, we proposed a model, in which inactivation of infectious ZIKV is gamma distributed and fit the model to the temporal measurements of infectious virus remaining in the media. The model was able to reproduce the data well and yielded the decay time of infectious ZIKV to be 40 h. We studied the in vitro ZIKV infection kinetics by conducting cell infection at two distinct multiplicity of infection and measuring viral loads over time. We fit the mathematical model of in vitro viral infection with gamma distributed degradation time of infectious virus to the viral growth data and identified the timespans and rates involved within the ZIKV-host cell interplay. Our mathematical analysis combined with the data provides a well-described example of non-exponential viral decay dynamics and presents numerical characterization of in vitro infection with ZIKV.
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18
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Ekwudu O, Devine GJ, Aaskov JG, Frentiu FD. Wolbachia strain wAlbB blocks replication of flaviviruses and alphaviruses in mosquito cell culture. Parasit Vectors 2020; 13:54. [PMID: 32041638 PMCID: PMC7011541 DOI: 10.1186/s13071-020-3936-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/03/2020] [Indexed: 11/10/2022] Open
Abstract
Background Wolbachia pipientis are bacterial endosymbionts of arthropods currently being implemented as biocontrol agents to reduce the global burden of arboviral diseases. Some strains of Wolbachia, when introduced into Aedes aegypti mosquitoes, reduce or block the replication of RNA viruses pathogenic to humans. The wAlbB strain of Wolbachia was originally isolated from Aedes albopictus, and when transinfected into Ae. aegypti, persists in mosquitoes under high temperature conditions longer than other strains. The utility of wAlbB to block a broad spectrum of RNA viruses has received limited attention. Here we test the ability of wAlbB to reduce or block the replication of a range of Flavivirus and Alphavirus species in cell culture. Methods The C6/36 mosquito cell line was stably infected with the wAlbB strain using the shell-vial technique. The replication of dengue, West Nile and three strains of Zika (genus Flavivirus), and Ross River, Barmah Forest and Sindbis (genus Alphavirus) viruses was compared in wAlbB-infected cells with Wolbachia-free controls. Infectious virus titres were determined using either immunofocus or plaque assays. A general linear model was used to test for significant differences in replication between flaviviruses and alphaviruses. Results Titres of all viruses were significantly reduced in cell cultures infected with wAlbB versus Wolbachia-free controls. The magnitude of reduction in virus yields varied among virus species and, within species, also among the strains utilized. Conclusion Our results suggest that wAlbB infection of arthropods could be used to reduce transmission of a wide range of pathogenic RNA viruses.![]()
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Affiliation(s)
- O'mezie Ekwudu
- School of Biomedical Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology, Herston, QLD, 4006, Australia.,Department of Microbiology, Chukwuemeka Odumegwu Ojukwu University, Uli, Nigeria.,Mosquito Control Laboratory, Queensland Institute of Medical Research Berghofer, Herston, QLD, 4006, Australia
| | - Gregor J Devine
- Mosquito Control Laboratory, Queensland Institute of Medical Research Berghofer, Herston, QLD, 4006, Australia
| | - John G Aaskov
- School of Biomedical Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology, Herston, QLD, 4006, Australia
| | - Francesca D Frentiu
- School of Biomedical Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology, Herston, QLD, 4006, Australia.
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19
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Ambagala A, Truong T, Cottam-Birt C, Berhane Y, Gerdts V, Karniychuk U, Safronetz D, Babiuk S. Susceptibility of Chicken Embryos, Sheep, Cattle, Pigs, and Chickens to Zika Virus Infection. Front Vet Sci 2020; 7:23. [PMID: 32118055 PMCID: PMC7012786 DOI: 10.3389/fvets.2020.00023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/13/2020] [Indexed: 01/01/2023] Open
Abstract
The susceptibility of sheep, cattle, pigs, chickens and chicken embryos to Zika virus infection was evaluated by experimental inoculation with Zika virus Thailand strain isolated from a Canadian traveler in 2013. The inoculated animals did not develop any clinical signs of disease nor evidence of Zika virus replication in peripheral blood, cerebrospinal fluid and tissues including brain and spinal cord assessed by real-time RT-PCR. Sera were also negative for Zika virus antibodies by Zika virus neutralization assays as well as Zika virus immunoperoxidase staining of Zika infected Vero cells. Chicken embryos were inoculated by different routes including yolk sac (4 day old embryos), chorioallantoic membrane (8 day old embryos), amniotic fluid (8 day old embryos) and intravenous routes (12 day old embryos). Virus replication in chicken embryos was observed in the brain and body tissues following intravenous (IV), yolk sac (YS), chorioallantoic membrane (CAM), and amniotic fluid (AF) inoculation routes. The highest mortality was observed in embryos inoculated via yolk sac. The dead embryos showed diffuse muscular hemorrhages. The yolk sac inoculated chicken embryos showed delayed hatching and displayed neurological signs immediately after hatching. These studies demonstrate that 8 week old sheep, 6 month old cattle, 4 week old pigs, and 4 week old chickens are not susceptible to Zika virus infection when inoculated experimentally and therefore unlikely to pose a risk as Zika virus reservoirs. However, chicken embryos are highly susceptible to Zika virus resulting in clinical disease of chicks after hatching. This study demonstrates that Zika virus has a tropism for embryonic tissue and that chicken embryos can be used as a model to study Zika virus replication and pathogenesis.
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Affiliation(s)
- Aruna Ambagala
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada.,Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada
| | - Thang Truong
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada
| | - Colleen Cottam-Birt
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada
| | - Yohannes Berhane
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada.,Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada
| | - Volker Gerdts
- Vaccine and Infectious Disease Organization-International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK, Canada.,Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, SK, Canada
| | - Uladzimir Karniychuk
- Vaccine and Infectious Disease Organization-International Vaccine Centre (VIDO-InterVac), University of Saskatchewan, Saskatoon, SK, Canada.,Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, SK, Canada
| | - David Safronetz
- Zoonotic Diseases and Special Pathogens, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - Shawn Babiuk
- Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, Winnipeg, MB, Canada.,Department of Immunology, University of Manitoba, Winnipeg, MB, Canada
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20
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Nelson BR, Roby JA, Dobyns WB, Rajagopal L, Gale M, Adams Waldorf KM. Immune Evasion Strategies Used by Zika Virus to Infect the Fetal Eye and Brain. Viral Immunol 2019; 33:22-37. [PMID: 31687902 PMCID: PMC6978768 DOI: 10.1089/vim.2019.0082] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Zika virus (ZIKV) is a mosquito-transmitted flavivirus that caused a public health emergency in the Americas when an outbreak in Brazil became linked to congenital microcephaly. Understanding how ZIKV could evade the innate immune defenses of the mother, placenta, and fetus has become central to determining how the virus can traffic into the fetal brain. ZIKV, like other flaviviruses, evades host innate immune responses by leveraging viral proteins and other processes that occur during viral replication to allow spread to the placenta. Within the placenta, there are diverse cell types with coreceptors for ZIKV entry, creating an opportunity for the virus to establish a reservoir for replication and infect the fetus. The fetal brain is vulnerable to ZIKV, particularly during the first trimester, when it is beginning a dynamic process, to form highly complex and specialized regions orchestrated by neuroprogenitor cells. In this review, we provide a conceptual framework to understand the different routes for viral trafficking into the fetal brain and the eye, which are most likely to occur early and later in pregnancy. Based on the injury profile in human and nonhuman primates, ZIKV entry into the fetal brain likely occurs across both the blood/cerebrospinal fluid barrier in the choroid plexus and the blood/brain barrier. ZIKV can also enter the eye by trafficking across the blood/retinal barrier. Ultimately, the efficient escape of innate immune defenses by ZIKV is a key factor leading to viral infection. However, the host immune response against ZIKV can lead to injury and perturbations in developmental programs that drive cellular division, migration, and brain growth. The combined effect of innate immune evasion to facilitate viral propagation and the maternal/placental/fetal immune response to control the infection will determine the extent to which ZIKV can injure the fetal brain.
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Affiliation(s)
- Branden R. Nelson
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - Justin A. Roby
- Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
- Department of Immunology, University of Washington, Seattle, Washington
| | - William B. Dobyns
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
- Department of Pediatrics, University of Washington, Seattle, Washington
| | - Lakshmi Rajagopal
- Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
- Department of Pediatrics, University of Washington, Seattle, Washington
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, Washington
- Department of Global Health, University of Washington, Seattle, Washington
| | - Michael Gale
- Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
- Department of Immunology, University of Washington, Seattle, Washington
- Department of Global Health, University of Washington, Seattle, Washington
| | - Kristina M. Adams Waldorf
- Center for Innate Immunity and Immune Disease, University of Washington, Seattle, Washington
- Department of Global Health, University of Washington, Seattle, Washington
- Department of Obstetrics and Gynecology, University of Washington, Seattle, Washington
- Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
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21
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Shaily S, Upadhya A. Zika virus: Molecular responses and tissue tropism in the mammalian host. Rev Med Virol 2019; 29:e2050. [PMID: 31095819 DOI: 10.1002/rmv.2050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 03/29/2019] [Accepted: 04/01/2019] [Indexed: 12/15/2022]
Abstract
Zika virus (ZIKV) outbreaks have raised alarm because of reports of congenital Zika virus syndrome in infants. The virus is also known to cause the debilitating Guillain-Barré syndrome in adults. As a result, extensive research has been carried out on the virus over the past few years. To study the molecular responses of viral infectivity in mammals, in vitro two-dimensional and three-dimensional cellular models have been employed. The in vivo models of mouse, pig, chicken, and nonhuman primates are primarily used to investigate the teratogenicity of the virus, to study effects of the virus on specific tissues, and to study the systemic effects of a proposed antiviral agent. The virus exhibits wide tissue tropism in the mammalian host. The major host tissues of viral persistence and propagation are neural tissue, ocular tissue, testicular tissue and placental tissue. An understanding of the function of viral components, viral replication cycle, and the molecular responses elicited in the host tissues is imperative for designing antiviral treatment strategies and for development of vaccines. This review provides an update on ZIKV research models and mammalian host responses with respect to ZIKV tissue infection.
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Affiliation(s)
- Sangya Shaily
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKM'S NMIMS, Mumbai, India
| | - Archana Upadhya
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKM'S NMIMS, Mumbai, India
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22
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da Silva SR, Cheng F, Huang IC, Jung JU, Gao SJ. Efficiencies and kinetics of infection in different cell types/lines by African and Asian strains of Zika virus. J Med Virol 2019; 91:179-189. [PMID: 30192399 PMCID: PMC6294704 DOI: 10.1002/jmv.25306] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 08/27/2018] [Indexed: 02/05/2023]
Abstract
After recent outbreaks, Zika virus (ZIKV) was linked to severe neurological diseases including Guillain-Barré syndrome in adults and microcephaly in newborns. The severities of pathological manifestations have been associated with different ZIKV strains. To better understand the tropism of ZIKV, we infected 10 human and four nonhuman cell lines (types) with two African (IbH30656 and MR766) and two Asian (PRVABC59 and H/FP/2013) ZIKV strains. Cell susceptibility to ZIKV infection was determined by examining viral titers, synthesis of viral proteins, and replication of positive and negative strands of viral genome. Among nonhuman cell lines, only Vero cells were efficiently infected by ZIKV. Among human cell lines, all were permissive to ZIKV infection. However, 293T and HeLa cells showed differential susceptibility towards African strains. In 293T cells, the NS1 protein was expressed at the high level by African strains but was almost not expressed by Asian strains though there was no obvious difference in viral genome replication, suggesting that the differential susceptibility might be controlled at the stage of viral protein translation. This study provides comprehensive results of the permissiveness of different cell types to both African and Asian ZIKV strains, which might help clarify their different pathogenesis.
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Affiliation(s)
- Suzane Ramos da Silva
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- UPMC Hillman Cancer Center, Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA, USA
- These authors contributed equally to this work
| | - Fan Cheng
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- These authors contributed equally to this work
| | - I-Chueh Huang
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Jae U. Jung
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Shou-Jiang Gao
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- UPMC Hillman Cancer Center, Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA, USA
- Laboratory of Human Virology and Oncology, Shantou University Medical College, Shantou, Guangdong, People’s Republic of China
- Corresponding author: Shou-Jiang Gao, Cancer Virology Program, UPMC Hillman Cancer Center, 5117 Centre Avenue, Pittsburgh, PA 15213; Phone: 412-623-1000; Fax: 412-623-3355;
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23
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The Oxysterol 7-Ketocholesterol Reduces Zika Virus Titers in Vero Cells and Human Neurons. Viruses 2018; 11:v11010020. [PMID: 30598036 PMCID: PMC6356585 DOI: 10.3390/v11010020] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/22/2018] [Accepted: 12/29/2018] [Indexed: 01/19/2023] Open
Abstract
Zika virus (ZIKV) is an emerging flavivirus responsible for a major epidemic in the Americas beginning in 2015. ZIKV associated with maternal infection can lead to neurological disorders in newborns, including microcephaly. Although there is an abundance of research examining the neurotropism of ZIKV, we still do not completely understand the mechanism by which ZIKV targets neural cells or how to limit neural cell infection. Recent research suggests that flaviviruses, including ZIKV, may hijack the cellular autophagy pathway to benefit their replication. Therefore, we hypothesized that ZIKV replication would be impacted when infected cells were treated with compounds that target the autophagy pathway. We screened a library of 94 compounds known to affect autophagy in both mammalian and insect cell lines. A subset of compounds that inhibited ZIKV replication without affecting cellular viability were tested for their ability to limit ZIKV replication in human neurons. From this second screen, we identified one compound, 7-ketocholesterol (7-KC), which inhibited ZIKV replication in neurons without significantly affecting neuron viability. Interestingly, 7-KC induces autophagy, which would be hypothesized to increase ZIKV replication, yet it decreased virus production. Time-of-addition experiments suggest 7-KC inhibits ZIKV replication late in the replication cycle. While 7-KC did not inhibit RNA replication, it decreased the number of particles in the supernatant and the relative infectivity of the released particles, suggesting it interferes with particle budding, release from the host cell, and particle integrity.
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24
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Jansen S, Heitmann A, Lühken R, Jöst H, Helms M, Vapalahti O, Schmidt-Chanasit J, Tannich E. Experimental transmission of Zika virus by Aedes japonicus japonicus from southwestern Germany. Emerg Microbes Infect 2018; 7:192. [PMID: 30482893 PMCID: PMC6258727 DOI: 10.1038/s41426-018-0195-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 10/16/2018] [Accepted: 10/25/2018] [Indexed: 01/08/2023]
Abstract
The invasive mosquito species Aedes japonicus japonicus (Ae. japonicus) is widely distributed in Central Europe and is a known vector of various arboviruses in the laboratory, including flaviviruses such as Japanese Encephalitis virus or West Nile virus. However, the vector competence of Ae. japonicus for the recently emerging Zika virus (ZIKV) has not been determined. Therefore, field-caught Ae. japonicus from Germany were orally infected with ZIKV and incubated at 21, 24, or 27 °C to evaluate the vector competence under climate conditions representative of the temperate regions (21 °C) in the species' main distribution area in Europe and of Mediterranean regions (27 °C). Aedes japonicus was susceptible to ZIKV at all temperatures, showing infection rates between 10.0% (21 °C) and 66.7% (27 °C). However, virus transmission was detected exclusively at 27 °C with a transmission rate of 14.3% and a transmission efficiency of 9.5%. Taking into account the present distribution of Ae. japonicus in the temperate regions of Central Europe, the risk of ZIKV transmission by the studied Ae. japonicus population in Central Europe has to be considered as low. Nevertheless, due to the species' vector competence for ZIKV and other mosquito-borne viruses, in combination with the possibility of further spread to Mediterranean regions, Ae. japonicus must be kept in mind as a potential vector of pathogens inside and outside of Europe.
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Affiliation(s)
- Stephanie Jansen
- Bernhard Nocht Institute for Tropical Medicine, 20359, Hamburg, Germany
- German Centre for Infection Research (DZIF), Partner site Hamburg-Luebeck-Borstel-Riems, 20359, Hamburg, Germany
| | - Anna Heitmann
- Bernhard Nocht Institute for Tropical Medicine, 20359, Hamburg, Germany.
| | - Renke Lühken
- Bernhard Nocht Institute for Tropical Medicine, 20359, Hamburg, Germany
| | - Hanna Jöst
- Bernhard Nocht Institute for Tropical Medicine, 20359, Hamburg, Germany
| | - Michelle Helms
- Bernhard Nocht Institute for Tropical Medicine, 20359, Hamburg, Germany
| | - Olli Vapalahti
- University of Helsinki and Helsinki University Hospital, 00100, Helsinki, Finland
| | - Jonas Schmidt-Chanasit
- Bernhard Nocht Institute for Tropical Medicine, 20359, Hamburg, Germany
- German Centre for Infection Research (DZIF), Partner site Hamburg-Luebeck-Borstel-Riems, 20359, Hamburg, Germany
| | - Egbert Tannich
- Bernhard Nocht Institute for Tropical Medicine, 20359, Hamburg, Germany
- German Centre for Infection Research (DZIF), Partner site Hamburg-Luebeck-Borstel-Riems, 20359, Hamburg, Germany
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25
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Growth and adaptation of Zika virus in mammalian and mosquito cells. PLoS Negl Trop Dis 2018; 12:e0006880. [PMID: 30418969 PMCID: PMC6258428 DOI: 10.1371/journal.pntd.0006880] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 11/26/2018] [Accepted: 09/28/2018] [Indexed: 01/02/2023] Open
Abstract
The recent emergence of Zika virus (ZIKV) in the Americas coincident with increased caseloads of microcephalic infants and Guillain-Barre syndrome has prompted a flurry of research on ZIKV. Much of the research is difficult to compare or repeat because individual laboratories use different virus isolates, growth conditions, and quantitative assays. Here we obtained three readily available contemporary ZIKV isolates and the prototype Ugandan isolate. We generated stocks of each on Vero mammalian cells (ZIKVmam) and C6/36 mosquito cells (ZIKVmos), determined titers by different assays side-by-side, compared growth characteristics using one-step and multi-step growth curves on Vero and C6/36 cells, and examined plaque phenotype. ZIKV titers consistently peaked earlier on Vero cells than on C6/36 cells. Contemporary ZIKV isolates reached peak titer most quickly in a multi-step growth curve when the amplifying cell line was the same as the titering cell line (e.g., ZIKVmam titered on Vero cells). Growth of ZIKVmam on mosquito cells was particularly delayed. These data suggest that the ability to infect and/or replicate in insect cells is limited after growth in mammalian cells. In addition, ZIKVmos typically had smaller, more homogenous plaques than ZIKVmam in a standard plaque assay. We hypothesized that the plaque size difference represented early adaptation to growth in mammalian cells. We plaque purified representative-sized plaques from ZIKVmos and ZIKVmam. ZIKVmos isolates maintained the initial phenotype while plaques from ZIKVmam isolates became larger with passaging. Our results underscore the importance of the cells used to produce viral stocks and the potential for adaptation with minimal cell passages. In addition, these studies provide a foundation to compare current and emerging ZIKV isolates in vitro and in vivo.
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26
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Zhang H, Li Y, Reall T, Xu Y, Goodman C, Saathoff S, Ringbauer J, Stanley D. Characterization of cell lines derived from the southern armyworm, Spodoptera eridania. In Vitro Cell Dev Biol Anim 2018; 54:749-755. [DOI: 10.1007/s11626-018-0300-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 09/27/2018] [Indexed: 12/14/2022]
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27
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Goodfellow FT, Willard KA, Wu X, Scoville S, Stice SL, Brindley MA. Strain-Dependent Consequences of Zika Virus Infection and Differential Impact on Neural Development. Viruses 2018; 10:v10100550. [PMID: 30304805 PMCID: PMC6212967 DOI: 10.3390/v10100550] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/02/2018] [Accepted: 10/04/2018] [Indexed: 12/16/2022] Open
Abstract
Maternal infection with Zika virus (ZIKV) during pregnancy can result in neonatal abnormalities, including neurological dysfunction and microcephaly. Experimental models of congenital Zika syndrome identified neural progenitor cells as a target of viral infection. Neural progenitor cells are responsible for populating the developing central nervous system with neurons and glia. Neural progenitor dysfunction can lead to severe birth defects, namely, lissencephaly, microcephaly, and cognitive deficits. For this study, the consequences of ZIKV infection in human pluripotent stem cell-derived neural progenitor (hNP) cells and neurons were evaluated. ZIKV isolates from Asian and African lineages displayed lineage-specific replication kinetics, cytopathic effects, and impacts on hNP function and neuronal differentiation. The currently circulating ZIKV isolates exhibit a unique profile of virulence, cytopathic effect, and impaired cellular functions that likely contribute to the pathological mechanism of congenital Zika syndrome. The authors found that infection with Asian-lineage ZIKV isolates impaired the proliferation and migration of hNP cells, and neuron maturation. In contrast, the African-lineage infections resulted in abrupt and extensive cell death. This work furthers the understanding of ZIKV-induced brain pathology.
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Affiliation(s)
- Forrest T Goodfellow
- Department of Animal and Dairy Science, Regenerative Bioscience Center, College of Agriculture and Environmental Science, University of Georgia, Athens, GA 30602, USA.
| | - Katherine A Willard
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
| | - Xian Wu
- Department of Animal and Dairy Science, Regenerative Bioscience Center, College of Agriculture and Environmental Science, University of Georgia, Athens, GA 30602, USA.
| | | | - Steven L Stice
- Department of Animal and Dairy Science, Regenerative Bioscience Center, College of Agriculture and Environmental Science, University of Georgia, Athens, GA 30602, USA.
| | - Melinda A Brindley
- Department of Infectious Diseases, Department of Population Health, Center for Vaccines and Immunology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
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28
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Beaver JT, Lelutiu N, Habib R, Skountzou I. Evolution of Two Major Zika Virus Lineages: Implications for Pathology, Immune Response, and Vaccine Development. Front Immunol 2018; 9:1640. [PMID: 30072993 PMCID: PMC6058022 DOI: 10.3389/fimmu.2018.01640] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 07/03/2018] [Indexed: 12/13/2022] Open
Abstract
Zika virus (ZIKV) became a public health emergency of global concern in 2015 due to its rapid expansion from French Polynesia to Brazil, spreading quickly throughout the Americas. Its unexpected correlation to neurological impairments and defects, now known as congenital Zika syndrome, brought on an urgency to characterize the pathology and develop safe, effective vaccines. ZIKV genetic analyses have identified two major lineages, Asian and African, which have undergone substantial changes during the past 50 years. Although ZIKV infections have been circulating throughout Africa and Asia for the later part of the 20th century, the symptoms were mild and not associated with serious pathology until now. ZIKV evolution also took the form of novel modes of transmission, including maternal-fetal transmission, sexual transmission, and transmission through the eye. The African and Asian lineages have demonstrated differential pathogenesis and molecular responses in vitro and in vivo. The limited number of human infections prior to the 21st century restricted ZIKV research to in vitro studies, but current animal studies utilize mice deficient in type I interferon (IFN) signaling in order to invoke enhanced viral pathogenesis. This review examines ZIKV strain differences from an evolutionary perspective, discussing how these differentially impact pathogenesis via host immune responses that modulate IFN signaling, and how these differential effects dictate the future of ZIKV vaccine candidates.
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Affiliation(s)
| | | | | | - Ioanna Skountzou
- Department of Microbiology and Immunology, Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, United States
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29
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Evans MV, Shiau JC, Solano N, Brindley MA, Drake JM, Murdock CC. Carry-over effects of urban larval environments on the transmission potential of dengue-2 virus. Parasit Vectors 2018; 11:426. [PMID: 30016993 PMCID: PMC6050736 DOI: 10.1186/s13071-018-3013-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/12/2018] [Indexed: 01/25/2023] Open
Abstract
Background Mosquitoes are strongly influenced by environmental temperatures, both directly and indirectly via carry-over effects, a phenomenon by which adult phenotypes are shaped indirectly by the environmental conditions experienced in previous life stages. In landscapes with spatially varying microclimates, such as a city, the effects of environmental temperature can therefore lead to spatial patterns in disease dynamics. To explore the contribution of carry-over effects on the transmission of dengue-2 virus (DENV-2), we conducted a semi-field experiment comparing the demographic and transmission rates of Aedes albopictus reared on different urban land classes in the summer and autumn season. We parameterized a model of vectorial capacity using field- and literature-derived measurements to estimate the bias introduced into predictions of vectorial capacity not accounting for carry-over effects. Results The larval environment of different land classes and seasons significantly impacted mosquito life history traits. Larval development and survival rates were higher in the summer than the autumn, with no difference across land class. The effect of land class on adult body size differed across season, with suburban mosquitoes having the smallest wing length in the summer and the largest wing length in the autumn, when compared to other land classes. Infection and dissemination rates were higher in the autumn and on suburban and rural land classes compared to urban. Infectiousness did not differ across land class or season. We estimate that not accounting for carry-over effects can underestimate disease transmission potential in suburban and urban sites in the summer by up to 25%. Conclusions Our findings demonstrate the potential of the larval environment to differentially impact stages of DENV-2 infection in Ae. albopictus mosquitoes via carry-over effects. Failure to account for carry-over effects of the larval environment in mechanistic models can lead to biased estimates of disease transmission potential at fine-scales in urban environments. Electronic supplementary material The online version of this article (10.1186/s13071-018-3013-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Michelle V Evans
- Odum School of Ecology, University of Georgia, Athens, GA, USA. .,Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA.
| | - Justine C Shiau
- Department of Infectious Disease, University of Georgia, Athens, GA, USA
| | - Nicole Solano
- Odum School of Ecology, University of Georgia, Athens, GA, USA.,Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Melinda A Brindley
- Department of Infectious Disease, University of Georgia, Athens, GA, USA.,Department of Population Health, University of Georgia, Athens, GA, USA.,Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA
| | - John M Drake
- Odum School of Ecology, University of Georgia, Athens, GA, USA.,Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Courtney C Murdock
- Odum School of Ecology, University of Georgia, Athens, GA, USA.,Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA.,Department of Infectious Disease, University of Georgia, Athens, GA, USA.,Center for Tropical Emerging Global Diseases, University of Georgia, Athens, GA, USA.,Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA.,River Basin Center, University of Georgia, Athens, GA, USA
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30
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Sheridan MA, Balaraman V, Schust DJ, Ezashi T, Roberts RM, Franz AWE. African and Asian strains of Zika virus differ in their ability to infect and lyse primitive human placental trophoblast. PLoS One 2018; 13:e0200086. [PMID: 29985932 PMCID: PMC6037361 DOI: 10.1371/journal.pone.0200086] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 06/19/2018] [Indexed: 01/08/2023] Open
Abstract
Zika virus (ZIKV) drew worldwide attention when a recent epidemic was linked to fetal microcephaly. Here we used human embryonic stem cell derived trophoblasts as a model for primitive placental trophoblast to test the hypothesis that there are differences in how the two genetically distinct ZIKV lineages, African (AF) and Asian (AS), target the human placenta. Upon infection with three AF (ib-H30656, SEN/1984/41525-DAK, and MR-766) and three AS (FSS13025, MexI-44, and PANcdc259249) ZIKV strains, we observed that severe placental cell lysis was only induced after infection with AF strains, while viral replication rates remained similar between both lineages. Differences in cytopathic effects (CPE) were not observed in Vero cells, indicating that the AF strains were not inherently superior at cell lysis. Taken together, we propose that infection with AF strains of ZIKV early in pregnancy would likely result in pregnancy loss, rather than allow further fetal development with accompanying brain damage. Our results also suggest that the long term laboratory-adapted MR-766 strain does not behave aberrantly in cell culture relative to other AF lineage strains.
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Affiliation(s)
- Megan A. Sheridan
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Biochemistry, University of Missouri, Columbia, Missouri, United States of America
| | - Velmurugan Balaraman
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
| | - Danny J. Schust
- Department of Obstetrics, Gynecology and Women's Health, University of Missouri, Columbia, Missouri, United States of America
| | - Toshihiko Ezashi
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Division of Animal Sciences, University of Missouri, Columbia, Missouri, United States of America
| | - R. Michael Roberts
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Biochemistry, University of Missouri, Columbia, Missouri, United States of America
- Division of Animal Sciences, University of Missouri, Columbia, Missouri, United States of America
| | - Alexander W. E. Franz
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
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Alfonso-Parra C, Avila FW. Molecular Responses to the Zika Virus in Mosquitoes. Pathogens 2018; 7:pathogens7020049. [PMID: 29751526 PMCID: PMC6027243 DOI: 10.3390/pathogens7020049] [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] [Received: 03/24/2018] [Revised: 04/23/2018] [Accepted: 04/28/2018] [Indexed: 12/17/2022] Open
Abstract
The Zika virus (ZIKV), originally discovered in 1947, did not become a major concern until the virus swept across the Pacific and into the Americas in the last decade, bringing with it news of neurological complications and birth defects in ZIKV affected areas. This prompted researchers to dissect the molecular interactions between ZIKV and the mosquito vector in an attempt to better understand not only the changes that occur upon infection, but to also identify molecules that may potentially enhance or suppress a mosquito’s ability to become infected and/or transmit the virus. Here, we review what is currently known regarding ZIKV-mosquito molecular interactions, focusing on ZIKV infection of Aedes aegypti and Aedes albopictus, the primary species implicated in transmitting ZIKV during the recent outbreaks.
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Affiliation(s)
- Catalina Alfonso-Parra
- Max Planck Tandem Group in Mosquito Reproductive Biology, University of Antioquia, Calle 67 #53-108, Medellín 050010, Colombia.
- Instituto Colombiano de Medicina Tropical, Carerra 43A # 52 sur-99, Sabaneta 055450, Colombia.
| | - Frank W Avila
- Max Planck Tandem Group in Mosquito Reproductive Biology, University of Antioquia, Calle 67 #53-108, Medellín 050010, Colombia.
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Mosquitoes as Arbovirus Vectors: From Species Identification to Vector Competence. PARASITOLOGY RESEARCH MONOGRAPHS 2018. [PMCID: PMC7122353 DOI: 10.1007/978-3-319-94075-5_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mosquitoes and other arthropods transmit a large number of medically important pathogens, in particular viruses. These arthropod-borne viruses (arboviruses) include a wide variety of RNA viruses belonging to the Flaviviridae family (West Nile virus (WNV), Usutu virus (USUV), Dengue virus (DENV), Japanese encephalitis virus (JEV), Zika virus (ZIKV)), the Togaviridae family (Chikungunya virus (CHIKV)), and Bunyavirales order (Rift Valley fever virus (RVFV)) (please refer also to Table 9.1). Arboviral transmission to humans and livestock constitutes a major threat to public health and economy as illustrated by the emergence of ZIKV in the Americas, RVFV outbreaks in Africa, and the worldwide outbreaks of DENV. To answer the question if those viral pathogens also pose a risk to Europe, we need to first answer the key questions (summarized in Fig. 9.1):Who could contribute to such an outbreak? Information about mosquito species resident or imported, potential hosts and viruses able to infect vectors and hosts in Germany is needed. Where would competent mosquito species meet favorable conditions for transmission? Information on the minimum requirements for efficient replication of the virus in a given vector species and subsequent transmission is needed. How do viruses and vectors interact to facilitate transmission? Information on the vector immunity, vector physiology, vector genetics, and vector microbiomes is needed.
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