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Phumee A, Chitcharoen S, Sutthanont N, Intayot P, Wacharapluesadee S, Siriyasatien P. Genetic diversity and phylogenetic analyses of Asian lineage Zika virus whole genome sequences derived from Culex quinquefasciatus mosquitoes and urine of patients during the 2020 epidemic in Thailand. Sci Rep 2023; 13:18470. [PMID: 37891235 PMCID: PMC10611781 DOI: 10.1038/s41598-023-45814-9] [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: 09/14/2023] [Accepted: 10/24/2023] [Indexed: 10/29/2023] Open
Abstract
Zika virus (ZIKV), a mosquito-borne flavivirus, has been continually emerging and re-emerging since 2010, with sporadic cases reported annually in Thailand, peaking at over 1000 confirmed positive cases in 2016. Leveraging high-throughput sequencing technologies, specifically whole genome sequencing (WGS), has facilitated rapid pathogen genome sequencing. In this study, we used multiplex amplicon sequencing on the Illumina Miseq instrument to describe ZIKV WGS. Six ZIKV WGS were derived from three samples of field-caught Culex quinquefasciatus mosquitoes (two males and one female) and three urine samples collected from patients in three different provinces of Thailand. Additionally, successful isolation of a ZIKV isolate occurred from a female Cx. quinquefasciatus. The WGS analysis revealed a correlation between the 2020 outbreak and the acquisition of five amino acid changes in the Asian lineage ZIKV strains from Thailand (2006), Cambodia (2010 and 2019), and the Philippines (2012). These changes, including C-T106A, prM-V1A, E-V473M, NS1-A188V, and NS5-M872V, were identified in all seven WGS, previously linked to significantly higher mortality rates. Furthermore, phylogenetic analysis indicated that the seven ZIKV sequences belonged to the Asian lineage. Notably, the genomic region of the E gene showed the highest nucleotide diversity (0.7-1.3%). This data holds significance in informing the development of molecular tools that enhance our understanding of virus patterns and evolution. Moreover, it may identify targets for improved methods to prevent and control future ZIKV outbreaks.
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Affiliation(s)
- Atchara Phumee
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand
- Excellent Center for Dengue and Community Public Health (EC for DACH), Walailak University, Nakhon Si Thammarat, Thailand
| | - Suwalak Chitcharoen
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Nataya Sutthanont
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Proawpilart Intayot
- Pharmaceutical Ingredient and Medical Device Research Division, Research Development and Innovation Department, The Government Pharmaceutical Organization, Bangkok, Thailand
| | - Supaporn Wacharapluesadee
- Thai Red Cross Emerging Infectious Diseases Clinical Center, King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Padet Siriyasatien
- Center of Excellence in Vector Biology and Vector Borne Diseases, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
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Molina BF, Marques NN, Bittar C, Batista MN, Rahal P. African ZIKV lineage fails to sustain infectivity in an in vitro mimetic urban cycle. Braz J Microbiol 2023; 54:1421-1431. [PMID: 37458982 PMCID: PMC10484821 DOI: 10.1007/s42770-023-01053-8] [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: 09/20/2022] [Accepted: 06/27/2023] [Indexed: 09/10/2023] Open
Abstract
Zika virus (ZIKV) is an arbovirus maintained in nature in two distinct cycles of transmission: urban and sylvatic. Each cycle includes specific vertebrate and invertebrate hosts, and through alternate infections, a conserved consensus sequence is maintained that might vary depending on the cycle. The current study aimed to investigate the ability of ZIKVAF and ZIKVBR to maintain an infectious cycle by alternating passages in cells mimicking the urban (UC) and semi-sylvatic (SC) cycles. The complete genome of the original inoculum and the last passages for each cycle were sequenced by Sanger. Ten passages were performed, as planned, for ZIKVBR UC, ZIKVAF SC, and ZIKVBR SC. ZIKVBR SC showed significant variation in viral titers along the passages, suggesting that the virus is not well adapted to the non-human primate host. ZIKVAF passage in UC was abrogated in the third passage, showing the inability of the African lineage to sustain cycles in human cells, suggesting a low capacity to establish an urban cycle. Several mutations were found in both strains along the passages, but not occurring at equivalent positions. Further studies are needed to elucidate whether any of these specific mutations affect viral fitness. ZIKV strains behave differently in artificial transmission cycles in vitro: Brazilian ZIKV was able to establish urban and semi-sylvatic cycles in vitro. African ZIKV proved unable to cycle among human and mosquito cells and is compatible only with the semi-sylvatic cycle. The main mutations arose in the NS2A region after artificial transmission cycles for both ZIKV strains but not at equivalent positions.
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Affiliation(s)
- Bárbara Floriano Molina
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
| | - Nayara Nathiê Marques
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
| | - Cíntia Bittar
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
- The Rockefeller University, 1230 York Ave, Manhattan, New York, NY 10065 USA
| | | | - Paula Rahal
- Laboratório de Estudos Genômicos, Departamento de Biologia, Instituto de Biociências Letras E Ciências Exatas (IBILCE), Universidade Estadual Paulista (Unesp), São José Do Rio Preto, Brazil
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3
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Chan KWK, Bifani AM, Watanabe S, Choy MM, Ooi EE, Vasudevan SG. Tissue-specific expansion of Zika virus isogenic variants drive disease pathogenesis. EBioMedicine 2023; 91:104570. [PMID: 37068347 PMCID: PMC10130475 DOI: 10.1016/j.ebiom.2023.104570] [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: 11/23/2022] [Revised: 03/09/2023] [Accepted: 03/30/2023] [Indexed: 04/19/2023] Open
Abstract
BACKGROUND The Asian lineage Zika virus (ZIKV) emerged as a public health emergency in 2016 causing severe neurological pathologies with no apparent historical correlate to the mild, disease-causing innocuous member of the mosquito-borne flavivirus genus that was discovered in Africa in 1947. Replication error rate of RNA viruses combined with viral protein/RNA structural plasticity can lead to evolution of virus-induced pathogenicity that is critical to identify and validate. METHODS Infection studies in cells and A129 interferon alpha/beta receptor deficient mice with ZIKV French Polynesian H/PF/2013 clinical isolate, plaque-purified isogenic clone derivatives as well as infectious cDNA clone derived wild-type and site-specific mutant viruses, were employed together with Next-Generation Sequencing (NGS) to pin-point the contributions of specific viral variants in neurovirulence recapitulated in our ZIKV mouse model. FINDINGS NGS analysis of the low-passage inoculum virus as well as mouse serum, brain and testis derived virus, revealed specific enrichment in the mouse brain that were not found in the other tissues. Specifically, non-structural (NS) protein 2A variant at position 117 along with changes in NS1 and NS4B were uniquely associated with the mouse brain isolate. Mutational analysis of these variants in cDNA infectious clones identified the NS2A A117V as the lethal pathogenic determinant with potential epistatic contribution of NS1 and NS4B variants in ZIKV brain penetrance. INTERPRETATION Our findings confirm that viral subpopulations drive ZIKV neuropathogenicity and identify specific sequence variants that expand in the mouse brain that associates with this phenotype which can serve as predictors of severe epidemics. FUNDING Duke-NUS Khoo Post-doctoral Fellowship Award 2020 (KWKC) and National Medical Research Council of Singapore grants MOH-000524 (OFIRG) (SW) and MOH-OFIRG20nov-0002 (SGV).
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Affiliation(s)
- Kitti Wing Ki Chan
- Program in Emerging Infectious Disease, Duke-NUS Medical School, 8 College Road, 169857, Singapore
| | - Amanda Makha Bifani
- Program in Emerging Infectious Disease, Duke-NUS Medical School, 8 College Road, 169857, Singapore
| | - Satoru Watanabe
- Program in Emerging Infectious Disease, Duke-NUS Medical School, 8 College Road, 169857, Singapore
| | - Milly M Choy
- Program in Emerging Infectious Disease, Duke-NUS Medical School, 8 College Road, 169857, Singapore
| | - Eng Eong Ooi
- Program in Emerging Infectious Disease, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, 117545, Singapore.
| | - Subhash G Vasudevan
- Program in Emerging Infectious Disease, Duke-NUS Medical School, 8 College Road, 169857, Singapore; Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, 117545, Singapore; Institute for Glycomics, Griffith University, Gold Coast Campus, Southport, Queensland, 4222, Australia.
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Ong'era EM, Mohammed KS, Makori TO, Bejon P, Ocholla-Oyier LI, Nokes DJ, Agoti CN, Githinji G. High-throughput sequencing approaches applied to SARS-CoV-2. Wellcome Open Res 2023. [DOI: 10.12688/wellcomeopenres.18701.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
High-throughput sequencing is crucial for surveillance and control of viral outbreaks. During the ongoing coronavirus disease 2019 (COVID-19) pandemic, advances in the high-throughput sequencing technology resources have enhanced diagnosis, surveillance, and vaccine discovery. From the onset of the pandemic in December 2019, several genome-sequencing approaches have been developed and supported across the major sequencing platforms such as Illumina, Oxford Nanopore, PacBio, MGI DNBSEQTM and Ion Torrent. Here, we share insights from the sequencing approaches developed for sequencing of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between December 2019 and October 2022.
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Leiva S, Bugnon Valdano M, Gardiol D. Unravelling the epidemiological diversity of Zika virus by analyzing key protein variations. Arch Virol 2023; 168:115. [PMID: 36943525 DOI: 10.1007/s00705-023-05726-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 01/19/2023] [Indexed: 03/23/2023]
Abstract
The consequences of Zika virus (ZIKV) infections were limited to sporadic mild diseases until almost a decade ago, when epidemic outbreaks took place, with quick spread into the Americas. Simultaneously, novel severe neurological manifestations of ZIKV infections were identified, including congenital microcephaly. However, why the epidemic strains behave differently is not yet completely understood, and many questions remain about the actual significance of genetic variations in the epidemiology and biology of ZIKV. In this study, we analysed a large number of viral sequences to identify genes with different levels of variability and patterns of genomic variations that could be associated with ZIKV diversity. We compared numerous epidemic strains with pre-epidemic strains, using the BWA-mem algorithm, and we also examined specific variations among the epidemic ZIKV strains derived from microcephaly cases. We identified several viral genes with dissimilar mutation rates among the ZIKV strain groups and novel protein variation profiles that might be associated with epidemiological particularities. Finally, we assessed the impact of the detected changes on the structure and stability of the NS1, NS5, and E proteins using the I-TASSER, trRosetta, and RaptorX modelling algorithms, and we found some interesting variations that might help to explain the heterogeneous features of the diverse ZIKA strains. This work contributes to the identification of genetic differences in the ZIKV genome that might have a phenotypic impact, providing a basis for future experimental analysis to elucidate the genetic causes of the recent ZIKV emergency.
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Affiliation(s)
- Santiago Leiva
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario-CONICET, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Marina Bugnon Valdano
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario-CONICET, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
| | - Daniela Gardiol
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Instituto de Biología Molecular y Celular de Rosario-CONICET, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
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6
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Li N, Deng CL, Li Q, Chen XL, Zhang B, Ye HQ. A safe replication-defective Zika virus vaccine protects mice from viral infection and vertical transmission. Antiviral Res 2023; 211:105549. [PMID: 36690159 DOI: 10.1016/j.antiviral.2023.105549] [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: 10/23/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 01/22/2023]
Abstract
With the explosive emergence of Zika virus (ZIKV) and the consequent devastating fetal malformations in infected expectant women, a safe and effective vaccine is urgently needed. Here, using our established NS1 trans-complementation system, we generated high titer of replication-defective ZIKV with NS1 deletion (ZIKV-ΔNS1) in the BHK-21 cell line stably expressing NS1 (BHKNS1). NS1 deletion of ZIKV-ΔNS1 was stably maintained as no replicative virus was found in naïve BHK-21 cells after continuous passaging of ZIKV-ΔNS1 in BHKNS1 cells. The safety of ZIKV-ΔNS1 was demonstrated when a high dose of ZIKV-ΔNS1 (107 IU) was used to infect the highly susceptible type I and type II interferon (IFN) receptor-deficient mice. ZIKV-ΔNS1 could induce antibody responses in both immunocompetent (BALB/c) and immunodeficient mice and a single dose of ZIKV-ΔNS1 vaccine protected the immunodeficient mice from a highly lethal dosage of challenge with WT ZIKV. ZIKV-ΔNS1 immunization also attenuated vertical transmission during pregnancy of type I IFN receptor-deficient IFNAR-/- mice and protected fetuses from ZIKV infection. Our data reported here not only provide a promising ZIKV vaccine candidate with a satisfied balance between safety and efficacy, but also demonstrate the potential of the NS1 trans-complementation system as a platform for flavivirus vaccine development, especially for highly pathogenic flaviviruses.
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Affiliation(s)
- Na Li
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Cheng-Lin Deng
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Qi Li
- College of Pharmacy and Drug Discovery Center for Infectious Diseases, Nankai University, Tianjin, 300350, China
| | - Xiao-Ling Chen
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bo Zhang
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
| | - Han-Qing Ye
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
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Bernardo-Menezes LC, Agrelli A, Oliveira ASLED, Moura RRD, Crovella S, Brandão LAC. An overview of Zika virus genotypes and their infectivity. Rev Soc Bras Med Trop 2022; 55:e02632022. [PMID: 36197380 PMCID: PMC9536801 DOI: 10.1590/0037-8682-0263-2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 08/31/2022] [Indexed: 11/22/2022] Open
Abstract
Zika virus (ZIKV) is an enveloped, single-stranded RNA arbovirus belonging to the
genus Flavivirus. It was first isolated from a sentinel monkey
in Uganda in 1947. More recently, ZIKV has undergone rapid geographic expansion
and has been responsible for outbreaks in Southeast Asia, the Pacific Islands,
and America. In this review, we have highlighted the influence of viral genetic
variants on ZIKV pathogenesis. Two major ZIKV genotypes (African and Asian) have
been identified. The Asian genotype is subdivided into Southwest Asia, Pacific
Island, and American strains, and is responsible for most outbreaks.
Non-synonymous mutations in ZIKV proteins C, prM, E, NS1, NS2A, NS2B, NS3, and
NS4B were found to have a higher prevalence and association with virulent
strains of the Asian genotype. Consequently, the Asian genotype appears to have
acquired higher cellular permissiveness, tissue persistence, and viral tropism
in human neural cells. Therefore, mutations in specific coding regions of the
Asian genotype may enhance ZIKV infectivity. Considering that mutations in the
genomes of emerging viruses may lead to new virulent variants in humans, there
is a potential for the re-emergence of new ZIKV cases in the future.
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Seabra SG, Libin PJK, Theys K, Zhukova A, Potter BI, Nebenzahl-Guimaraes H, Gorbalenya AE, Sidorov IA, Pimentel V, Pingarilho M, de Vasconcelos ATR, Dellicour S, Khouri R, Gascuel O, Vandamme AM, Baele G, Cuypers L, Abecasis AB. OUP accepted manuscript. Virus Evol 2022; 8:veac029. [PMID: 35478717 PMCID: PMC9035895 DOI: 10.1093/ve/veac029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 01/24/2022] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
The Zika virus (ZIKV) disease caused a public health emergency of international concern that started in February 2016. The overall number of ZIKV-related cases increased until November 2016, after which it declined sharply. While the evaluation of the potential risk and impact of future arbovirus epidemics remains challenging, intensified surveillance efforts along with a scale-up of ZIKV whole-genome sequencing provide an opportunity to understand the patterns of genetic diversity, evolution, and spread of ZIKV. However, a classification system that reflects the true extent of ZIKV genetic variation is lacking. Our objective was to characterize ZIKV genetic diversity and phylodynamics, identify genomic footprints of differentiation patterns, and propose a dynamic classification system that reflects its divergence levels. We analysed a curated dataset of 762 publicly available sequences spanning the full-length coding region of ZIKV from across its geographical span and collected between 1947 and 2021. The definition of genetic groups was based on comprehensive evolutionary dynamics analyses, which included recombination and phylogenetic analyses, within- and between-group pairwise genetic distances comparison, detection of selective pressure, and clustering analyses. Evidence for potential recombination events was detected in a few sequences. However, we argue that these events are likely due to sequencing errors as proposed in previous studies. There was evidence of strong purifying selection, widespread across the genome, as also detected for other arboviruses. A total of 50 sites showed evidence of positive selection, and for a few of these sites, there was amino acid (AA) differentiation between genetic clusters. Two main genetic clusters were defined, ZA and ZB, which correspond to the already characterized ‘African’ and ‘Asian’ genotypes, respectively. Within ZB, two subgroups, ZB.1 and ZB.2, represent the Asiatic and the American (and Oceania) lineages, respectively. ZB.1 is further subdivided into ZB.1.0 (a basal Malaysia sequence sampled in the 1960s and a recent Indian sequence), ZB.1.1 (South-Eastern Asia, Southern Asia, and Micronesia sequences), and ZB.1.2 (very similar sequences from the outbreak in Singapore). ZB.2 is subdivided into ZB.2.0 (basal American sequences and the sequences from French Polynesia, the putative origin of South America introduction), ZB.2.1 (Central America), and ZB.2.2 (Caribbean and North America). This classification system does not use geographical references and is flexible to accommodate potential future lineages. It will be a helpful tool for studies that involve analyses of ZIKV genomic variation and its association with pathogenicity and serve as a starting point for the public health surveillance and response to on-going and future epidemics and to outbreaks that lead to the emergence of new variants.
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Affiliation(s)
| | | | | | - Anna Zhukova
- Institut Pasteur, Université Paris Cité, Unité Bioinformatique Evolutive, 25-28 rue du Dr Roux, Paris F-75015, France
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, 25-28 rue du Dr Roux, Paris F-75015, France
| | | | - Hanna Nebenzahl-Guimaraes
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Rua da Junqueira 100, Lisboa 1349-008, Portugal
| | | | | | - Victor Pimentel
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Rua da Junqueira 100, Lisboa 1349-008, Portugal
| | - Marta Pingarilho
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Rua da Junqueira 100, Lisboa 1349-008, Portugal
| | | | - Simon Dellicour
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Laboratory of Clinical and Epidemiological Virology, KU Leuven, Herestraat 49 - box 1030, Leuven 3000, Belgium
- Spatial Epidemiology Lab (SpELL), Université Libre de Bruxelles, CP 264/3, 50 av. F.D. Roosevelt, Bruxelles B-1050, Belgium
| | | | | | | | | | - Lize Cuypers
- Department of Laboratory Medicine, University Hospitals Leuven, Herestraat 49, Leuven 3000, Belgium
| | - Ana B Abecasis
- Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa (UNL), Rua da Junqueira 100, Lisboa 1349-008, Portugal
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Nakayama E, Kato F, Tajima S, Ogawa S, Yan K, Takahashi K, Sato Y, Suzuki T, Kawai Y, Inagaki T, Taniguchi S, Le TT, Tang B, Prow NA, Uda A, Maeki T, Lim CK, Khromykh AA, Suhrbier A, Saijo M. Neuroinvasiveness of the MR766 strain of Zika virus in IFNAR-/- mice maps to prM residues conserved amongst African genotype viruses. PLoS Pathog 2021; 17:e1009788. [PMID: 34310650 PMCID: PMC8341709 DOI: 10.1371/journal.ppat.1009788] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 08/05/2021] [Accepted: 07/07/2021] [Indexed: 12/23/2022] Open
Abstract
Zika virus (ZIKV) strains are classified into the African and Asian genotypes. The higher virulence of the African MR766 strain, which has been used extensively in ZIKV research, in adult IFNα/β receptor knockout (IFNAR-/-) mice is widely viewed as an artifact associated with mouse adaptation due to at least 146 passages in wild-type suckling mouse brains. To gain insights into the molecular determinants of MR766's virulence, a series of genes from MR766 were swapped with those from the Asian genotype PRVABC59 isolate, which is less virulent in IFNAR-/- mice. MR766 causes 100% lethal infection in IFNAR-/- mice, but when the prM gene of MR766 was replaced with that of PRVABC59, the chimera MR/PR(prM) showed 0% lethal infection. The reduced virulence was associated with reduced neuroinvasiveness, with MR766 brain titers ≈3 logs higher than those of MR/PR(prM) after subcutaneous infection, but was not significantly different in brain titers of MR766 and MR/PR(prM) after intracranial inoculation. MR/PR(prM) also showed reduced transcytosis when compared with MR766 in vitro. The high neuroinvasiveness of MR766 in IFNAR-/- mice could be linked to the 10 amino acids that differ between the prM proteins of MR766 and PRVABC59, with 5 of these changes affecting positive charge and hydrophobicity on the exposed surface of the prM protein. These 10 amino acids are highly conserved amongst African ZIKV isolates, irrespective of suckling mouse passage, arguing that the high virulence of MR766 in adult IFNAR-/- mice is not the result of mouse adaptation.
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Affiliation(s)
- Eri Nakayama
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Fumihiro Kato
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Shigeru Tajima
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Shinya Ogawa
- Department of Applied Biological Chemistry, School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Kexin Yan
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Kenta Takahashi
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yuko Sato
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tadaki Suzuki
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yasuhiro Kawai
- Management Department of Biosafety and Laboratory Animal, Division of Biosafety Control and Research, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takuya Inagaki
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Satoshi Taniguchi
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Thuy T. Le
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Bing Tang
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Natalie A. Prow
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Australian Infectious Disease Research Centre, GVN Center of Excellence, The University of Queensland and QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Akihiko Uda
- Department of Veterinary Science, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takahiro Maeki
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Chang-Kweng Lim
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Alexander A. Khromykh
- Australian Infectious Disease Research Centre, GVN Center of Excellence, The University of Queensland and QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Andreas Suhrbier
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Australian Infectious Disease Research Centre, GVN Center of Excellence, The University of Queensland and QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Masayuki Saijo
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
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de Alwis R, Zellweger RM, Chua E, Wang LF, Chawla T, Sessions OM, Marlier D, Connolly JE, von Messling V, Anderson DE. Systemic inflammation, innate immunity and pathogenesis after Zika virus infection in cynomolgus macaques are modulated by strain-specificity within the Asian lineage. Emerg Microbes Infect 2021; 10:1457-1470. [PMID: 34120576 PMCID: PMC8300938 DOI: 10.1080/22221751.2021.1943536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Zika virus (ZIKV) is an emerging arbovirus with recent global expansion. Historically, ZIKV infections with Asian lineages have been associated with mild disease such as rash and fever. However, recent Asian sub-lineages have caused outbreaks in the South Pacific and Latin America with increased prevalence of neurological disorders in infants and adults. Asian sub-lineage differences may partially explain the range of disease severity observed. However, the effect of Asian sub-lineage differences on pathogenesis remains poorly characterized. Current study conducts a head-to-head comparison of three Asian sub-lineages that are representative of the circulating ancestral mild Asian strain (ZIKV-SG), the 2007 epidemic French Polynesian strain (ZIKV-FP), and the 2013 epidemic Brazil strain (ZIKV-Brazil) in adult Cynomolgus macaques. Animals infected intervenously or subcutaneously with either of the three clinical isolates showed sub-lineage-specific differences in viral pathogenesis, early innate immune responses and systemic inflammation. Despite the lack of neurological symptoms in infected animals, the epidemiologically neurotropic ZIKV sub-lineages (ZIKV-Brazil and/or ZIKV-FP) were associated with more sustained viral replication, higher systemic inflammation (i.e. higher levels of TNFα, MCP-1, IL15 and G-CSF) and greater percentage of CD14+ monocytes and dendritic cells in blood. Multidimensional analysis showed clustering of ZIKV-SG away from ZIKV-Brazil and ZIKV-FP, further confirming sub-lineage differences in the measured parameters. These findings highlight greater systemic inflammation and monocyte recruitment as possible risk factors of adult ZIKV disease observed during the 2007 FP and 2013 Brazil epidemics. Future studies should explore the use of anti-inflammatory therapeutics as early treatment to prevent ZIKV-associated disease in adults.
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Affiliation(s)
- Ruklanthi de Alwis
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore.,Viral Research and Experimental Medicine Centre, SingHealth-Duke NUS, Singapore
| | | | - Edmond Chua
- Institute of Molecular and Cell Biology, A*STAR, Singapore
| | - Lin-Fa Wang
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Tanu Chawla
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - October M Sessions
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore.,Saw Swee Hock School of Public Health, National University of Singapore, Singapore.,Department of Pharmacy, National University of Singapore, Singapore
| | - Damien Marlier
- Institute of Molecular and Cell Biology, A*STAR, Singapore
| | - John E Connolly
- Institute of Molecular and Cell Biology, A*STAR, Singapore.,Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Institute of Biomedical Studies, Baylor University, Waco, TX, USA
| | - Veronika von Messling
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore.,Veterinary Medicine Division, Paul-Ehrlich-Institute, Langen, Germany
| | - Danielle E Anderson
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore.,Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
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11
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Attenuated dengue viruses are genetically more diverse than their respective wild-type parents. NPJ Vaccines 2021; 6:76. [PMID: 34017007 PMCID: PMC8138019 DOI: 10.1038/s41541-021-00340-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/31/2021] [Indexed: 11/09/2022] Open
Abstract
Dengue poses a significant burden of individual health, health systems and the economy in dengue endemic regions. As such, dengue vaccine development has been an active area of research. Previous studies selected attenuated vaccine candidates based on plaque size. However, these candidates led to mixed safety outcome in clinical trials, suggesting it is insufficiently informative as an indicator of dengue virus (DENV) attenuation. In this study, we examined the genome diversity of wild-type DENVs and their attenuated derivatives developed by Mahidol University and tested in phase 1 clinical trials. We found that the attenuated DENVs, in particular the strain under clinical development by Takeda Vaccines, DENV2 PDK53, showed significantly higher genome diversity than its wild-type parent, DENV2 16681. The determinant of genomic diversity was intrinsic to the PDK53 genome as infectious clone of PDK53 showed greater genomic diversity after a single in vitro passage compared to 16681 infectious clone. Similar trends were observed with attenuated DENV1 and DENV4, both of which were shown to be attenuated clinically, but not DENV3 that was not adequately attenuated clinically. Taken together, evidence presented here suggests that genome diversity could be developed into a marker of DENV attenuation.
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12
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Zika Virus Pathogenesis: A Battle for Immune Evasion. Vaccines (Basel) 2021; 9:vaccines9030294. [PMID: 33810028 PMCID: PMC8005041 DOI: 10.3390/vaccines9030294] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 12/13/2022] Open
Abstract
Zika virus (ZIKV) infection and its associated congenital and other neurological disorders, particularly microcephaly and other fetal developmental abnormalities, constitute a World Health Organization (WHO) Zika Virus Research Agenda within the WHO’s R&D Blueprint for Action to Prevent Epidemics, and continue to be a Public Health Emergency of International Concern (PHEIC) today. ZIKV pathogenicity is initiated by viral infection and propagation across multiple placental and fetal tissue barriers, and is critically strengthened by subverting host immunity. ZIKV immune evasion involves viral non-structural proteins, genomic and non-coding RNA and microRNA (miRNA) to modulate interferon (IFN) signaling and production, interfering with intracellular signal pathways and autophagy, and promoting cellular environment changes together with secretion of cellular components to escape innate and adaptive immunity and further infect privileged immune organs/tissues such as the placenta and eyes. This review includes a description of recent advances in the understanding of the mechanisms underlying ZIKV immune modulation and evasion that strongly condition viral pathogenesis, which would certainly contribute to the development of anti-ZIKV strategies, drugs, and vaccines.
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13
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Adam A, Fontes-Garfias CR, Sarathy VV, Liu Y, Luo H, Davis E, Li W, Muruato AE, Wang B, Ahatov R, Mahmoud Y, Shan C, Osman SR, Widen SG, Barrett ADT, Shi PY, Wang T. A genetically stable Zika virus vaccine candidate protects mice against virus infection and vertical transmission. NPJ Vaccines 2021; 6:27. [PMID: 33597526 PMCID: PMC7889622 DOI: 10.1038/s41541-021-00288-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 01/15/2021] [Indexed: 12/20/2022] Open
Abstract
Although live attenuated vaccines (LAVs) have been effective in the control of flavivirus infections, to date they have been excluded from Zika virus (ZIKV) vaccine trials due to safety concerns. We have previously reported two ZIKV mutants, each of which has a single substitution in either envelope (E) glycosylation or nonstructural (NS) 4B P36 and displays a modest reduction in mouse neurovirulence and neuroinvasiveness, respectively. Here, we generated a ZIKV mutant, ZE4B-36, which combines mutations in both E glycosylation and NS4B P36. The ZE4B-36 mutant is stable and attenuated in viral replication. Next-generation sequence analysis showed that the attenuating mutations in the E and NS4B proteins are retained during serial cell culture passages. The mutant exhibits a significant reduction in neuroinvasiveness and neurovirulence and low infectivity in mosquitoes. It induces robust ZIKV-specific memory B cell, antibody, and T cell-mediated immune responses in type I interferon receptor (IFNR) deficient mice. ZIKV-specific T cell immunity remains strong months post-vaccination in wild-type C57BL/6 (B6) mice. Vaccination with ZE4B-36 protects mice from ZIKV-induced diseases and vertical transmission. Our results suggest that combination mutations in E glycosylation and NS4B P36 contribute to a candidate LAV with significantly increased safety but retain strong immunogenicity for prevention and control of ZIKV infection.
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Affiliation(s)
- Awadalkareem Adam
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Camila R Fontes-Garfias
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Vanessa V Sarathy
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Yang Liu
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Huanle Luo
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Emily Davis
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
| | - Wenqian Li
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Antonio E Muruato
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Binbin Wang
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Renat Ahatov
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Yoseph Mahmoud
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Chao Shan
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Samantha R Osman
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Steven G Widen
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
- Molecular Genomics Core Facility, University of Texas Medical Branch, Galveston, TX, USA
| | - Alan D T Barrett
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Pei-Yong Shi
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA.
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA.
- Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA.
| | - Tian Wang
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, TX, USA.
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA.
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX, USA.
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14
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Johnson KEE, Noval MG, Rangel MV, De Jesus E, Geber A, Schuster S, Cadwell K, Ghedin E, Stapleford KA. Mapping the evolutionary landscape of Zika virus infection in immunocompromised mice. Virus Evol 2020; 6:veaa092. [PMID: 33408879 PMCID: PMC7772475 DOI: 10.1093/ve/veaa092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The fundamental basis of how arboviruses evolve in nature and what regulates the adaptive process remain unclear. To address this problem, we established a Zika virus (ZIKV) vector-borne transmission system in immunocompromised mice to study the evolutionary characteristics of ZIKV infection. Using this system, we defined factors that influence the evolutionary landscape of ZIKV infection and show that transmission route and specific organ microenvironments impact viral diversity and defective viral genome production. In addition, we identified in mice the emergence of ZIKV mutants previously seen in natural infections, including variants present in currently circulating Asian and American strains, as well as mutations unique to the mouse infections. With these studies, we have established an insect-to-mouse transmission model to study ZIKV evolution in vivo. We also defined how organ microenvironments and infection route impact the ZIKV evolutionary landscape, providing a deeper understanding of the factors that regulate arbovirus evolution and emergence.
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Affiliation(s)
| | | | | | - Elfie De Jesus
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
| | - Adam Geber
- Department of Biology, Center for Genomics & Systems Biology, New York University, New York, NY, USA
| | - Samantha Schuster
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY 10016, USA
| | - Ken Cadwell
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, NY 10016, USA
| | - Elodie Ghedin
- Present address: National Institutes of Health/NIAID,
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15
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Using Next Generation Sequencing to Study the Genetic Diversity of Candidate Live Attenuated Zika Vaccines. Vaccines (Basel) 2020; 8:vaccines8020161. [PMID: 32260110 PMCID: PMC7349499 DOI: 10.3390/vaccines8020161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 03/27/2020] [Accepted: 03/31/2020] [Indexed: 12/15/2022] Open
Abstract
Zika virus (ZIKV) is a mosquito-transmitted positive-sense RNA virus in the family Flaviviridae. Candidate live-attenuated vaccine (LAV) viruses with engineered deletions in the 3’ untranslated region (UTR) provide immunity and protection in animal models of ZIKV infection, and phenotypic studies show that LAVs retain protective abilities following in vitro passage. The present study investigated the genetic diversity of wild-type (WT) parent ZIKV and its candidate LAVs using next generation sequencing analysis of five sequential in vitro passages. The results show that genomic entropy of WT ZIKV steadily increases during in vitro passage, whereas that of LAVs also increased by passage number five but was variable throughout passaging. Additionally, clusters of single nucleotide variants (SNVs) were found to be present in the pre-membrane/membrane (prM), envelope (E), nonstructural protein NS1 (NS1), and other nonstructural protein genes, depending on the specific deletion, whereas in the parent WT ZIKV, they are more abundant in prM and NS1. Ultimately, both the parental WT and LAV derivatives increase in genetic diversity, with evidence of adaptation following passage.
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16
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Li L, Collins ND, Widen SG, Davis EH, Kaiser JA, White MM, Greenberg MB, Barrett ADT, Bourne N, Sarathy VV. Attenuation of Zika Virus by Passage in Human HeLa Cells. Vaccines (Basel) 2019; 7:vaccines7030093. [PMID: 31434319 PMCID: PMC6789458 DOI: 10.3390/vaccines7030093] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/14/2019] [Accepted: 08/16/2019] [Indexed: 12/14/2022] Open
Abstract
Zika virus (ZIKV) is a mosquito-borne Flavivirus. Previous studies have shown that mosquito-transmitted flaviviruses, including yellow fever, Japanese encephalitis, and West Nile viruses, could be attenuated by serial passaging in human HeLa cells. Therefore, it was hypothesized that wild-type ZIKV would also be attenuated after HeLa cell passaging. A human isolate from the recent ZIKV epidemic was subjected to serial HeLa cell passaging, resulting in attenuated in vitro replication in both Vero and A549 cells. Additionally, infection of AG129 mice with 10 plaque forming units (pfu) of wild-type ZIKV led to viremia and mortality at 12 days, whereas infection with 103 pfu of HeLa-passage 6 (P6) ZIKV led to lower viremia, significant delay in mortality (median survival: 23 days), and increased cytokine and chemokine responses. Genomic sequencing of HeLa-passaged virus identified two amino acid substitutions as early as HeLa-P3: pre-membrane E87K and nonstructural protein 1 R103K. Furthermore, both substitutions were present in virus harvested from HeLa-P6-infected animal tissue. Together, these data show that, similarly to other mosquito-borne flaviviruses, ZIKV is attenuated following passaging in HeLa cells. This strategy can be used to improve understanding of substitutions that contribute to attenuation of ZIKV and be applied to vaccine development across multiple platforms.
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Affiliation(s)
- Li Li
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Natalie D Collins
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Viral Disease Branch, Walter Reed Army Institute for Research, Silver Spring, MD 20910, USA
| | - Steven G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Emily H Davis
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Jaclyn A Kaiser
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Mellodee M White
- Department of Pediatrics, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - M Banks Greenberg
- Department of Pediatrics, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Alan D T Barrett
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Nigel Bourne
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Department of Pediatrics, University of Texas Medical Branch, Galveston, TX 77555, USA
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Vanessa V Sarathy
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA.
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