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Le Dortz LL, Rouxel C, Polack B, Boulouis HJ, Lagrée AC, Deshuillers PL, Haddad N. Tick-borne diseases in Europe: Current prevention, control tools and the promise of aptamers. Vet Parasitol 2024; 328:110190. [PMID: 38714064 DOI: 10.1016/j.vetpar.2024.110190] [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: 10/27/2023] [Revised: 04/03/2024] [Accepted: 04/23/2024] [Indexed: 05/09/2024]
Abstract
In Europe, tick-borne diseases (TBDs) cause significant morbidity and mortality, affecting both human and animal health. Ticks can transmit a wide variety of pathogens (bacteria, viruses, and parasites) and feed on many vertebrate hosts. The incidence and public health burden of TBDs are tending to intensify in Europe due to various factors, mainly anthropogenic and often combined. Early detection of tick-borne pathogens (TBPs), preventive measures and treatment are of great importance to control TBDs and their expansion. However, there are various limitations in terms of the sensitivity and/or specificity of detection and prevention methods, and even in terms of feasibility. Aptamers are single-stranded DNA or RNA that could address these issues as they are able to bind with high affinity and specificity to a wide range of targets (e.g., proteins, small compounds, and cells) due to their unique three-dimensional structure. To date, aptamers have been selected against TBPs such as tick-borne encephalitis virus, Francisella tularensis, and Rickettsia typhi. These studies have demonstrated the benefits of aptamer-based assays for pathogen detection and medical diagnosis. In this review, we address the applications of aptamers to TBDs and discuss their potential for improving prevention measures (use of chemical acaricides, vaccination), diagnosis and therapeutic strategies to control TBDs.
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Affiliation(s)
- Lisa Lucie Le Dortz
- ANSES, INRAE, EnvA (Ecole nationale vétérinaire d'Alfort), UMR BIPAR, Laboratory of Animal Health, Maisons-Alfort F-94700, France
| | - Clotilde Rouxel
- ANSES, INRAE, EnvA (Ecole nationale vétérinaire d'Alfort), UMR BIPAR, Laboratory of Animal Health, Maisons-Alfort F-94700, France
| | - Bruno Polack
- ANSES, INRAE, EnvA (Ecole nationale vétérinaire d'Alfort), UMR BIPAR, Laboratory of Animal Health, Maisons-Alfort F-94700, France
| | - Henri-Jean Boulouis
- ANSES, INRAE, EnvA (Ecole nationale vétérinaire d'Alfort), UMR BIPAR, Laboratory of Animal Health, Maisons-Alfort F-94700, France
| | - Anne-Claire Lagrée
- ANSES, INRAE, EnvA (Ecole nationale vétérinaire d'Alfort), UMR BIPAR, Laboratory of Animal Health, Maisons-Alfort F-94700, France
| | - Pierre Lucien Deshuillers
- ANSES, INRAE, EnvA (Ecole nationale vétérinaire d'Alfort), UMR BIPAR, Laboratory of Animal Health, Maisons-Alfort F-94700, France
| | - Nadia Haddad
- ANSES, INRAE, EnvA (Ecole nationale vétérinaire d'Alfort), UMR BIPAR, Laboratory of Animal Health, Maisons-Alfort F-94700, France.
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Beranek MD, Giayetto O, Fischer S, Diaz A. Assessment of Mayaro virus vector competence of the mosquito Aedes aegypti (Linnaeus, 1762) populations in Argentine using dose-response assays. MEDICAL AND VETERINARY ENTOMOLOGY 2024; 38:234-243. [PMID: 38489505 DOI: 10.1111/mve.12712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 02/23/2024] [Indexed: 03/17/2024]
Abstract
Mayaro virus (MAYV; Alphavirus: Togaviridae) is an emerging pathogen in Latin America, causing fever and polyarthritis. Sporadic outbreaks of MAYV have occurred in the region, with reported human cases being imported to Europe and North America. Although primarily a risk for those residing in the Amazon basin's tropical forests, recent reports highlight that urbanization would increase the risk of MAYV transmission in Latin America. Urban emergence depends on human susceptibility and the ability of mosquitos like Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae) to transmit MAYV. Despite the absence of active MAYV transmission in Argentine, the risk of introduction is substantial due to human movement and the presence of Ae. aegypti in the region. This study aimed to evaluate the susceptibility of different Argentine Ae. aegypti populations to MAYV genotype L (MAYV-L) using dose-response assays and determine barriers to virus infection, dissemination and transmission. Immature mosquito stages were collected in Buenos Aires, Córdoba and Rosario cities. Female Ae. aegypti (F2) were orally infected by feeding on five concentrations of MAYV-L, ranging from 1.0 to 6.0 log10 PFU/mL. Abdomens, legs and saliva were analysed using viral plaque assays. Results revealed that MAYV-L between infection and dissemination were associated with viral doses rather than the population origin. Infection rates varied between 3% and 65%, with a 50% infectious dose >5.5 log10 PFU/mL. Dissemination occurred at 39%, with a 50% dissemination dose of ~6.0 log10 PFU/mL. Dissemination among infected mosquitoes ranged from 60% to 86%, and transmission from disseminated mosquitoes ranged from 11% to 20%. Argentine Ae. aegypti populations exhibited a need for higher viral doses of MAYV-L than those typically found in humans to become infected. In addition, only a small proportion of infected mosquitoes were capable of transmitting the virus. Understanding MAYV transmission in urban areas is crucial for public health interventions.
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Affiliation(s)
- Mauricio Daniel Beranek
- Laboratorio de Arbovirus, Instituto de Virología "Dr. J. M. Vanella", Facultad de Medicina, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Octavio Giayetto
- Laboratorio de Arbovirus, Instituto de Virología "Dr. J. M. Vanella", Facultad de Medicina, Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto de Investigaciones Biológicas y Tecnológicas, CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Sylvia Fischer
- Departamento de Ecología, Genética y Evolución Instituto de Ecología, Genética y Evolución de Buenos Aires, Facultad de Ciencias Exactas Físicas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Adrián Diaz
- Laboratorio de Arbovirus, Instituto de Virología "Dr. J. M. Vanella", Facultad de Medicina, Universidad Nacional de Córdoba, Córdoba, Argentina
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Ander SE, Carpentier KS, Sanders W, Lucas CJ, Jolly AJ, Johnson CN, Hawman DW, Heise MT, Moorman NJ, Morrison TE. A 44-Nucleotide Region in the Chikungunya Virus 3' UTR Dictates Viral Fitness in Disparate Host Cells. Viruses 2024; 16:861. [PMID: 38932154 PMCID: PMC11209300 DOI: 10.3390/v16060861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 05/24/2024] [Accepted: 05/27/2024] [Indexed: 06/28/2024] Open
Abstract
We previously reported that deletion of a 44-nucleotide element in the 3' untranslated region (UTR) of the Chikungunya virus (CHIKV) genome enhances the virulence of CHIKV infection in mice. Here, we find that while this 44-nucleotide deletion enhances CHIKV fitness in murine embryonic fibroblasts in a manner independent of the type I interferon response, the same mutation decreases viral fitness in C6/36 mosquito cells. Further, the fitness advantage conferred by the UTR deletion in mammalian cells is maintained in vivo in a mouse model of CHIKV dissemination. Finally, SHAPE-MaP analysis of the CHIKV 3' UTR revealed this 44-nucleotide element forms a distinctive two-stem-loop structure that is ablated in the mutant 3' UTR without altering additional 3' UTR RNA secondary structures.
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Affiliation(s)
- Stephanie E. Ander
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA (A.J.J.)
| | - Kathryn S. Carpentier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA (A.J.J.)
| | - Wes Sanders
- Department of Microbiology & Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Cormac J. Lucas
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA (A.J.J.)
| | - Austin J. Jolly
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA (A.J.J.)
| | - Cydney N. Johnson
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA (A.J.J.)
| | - David W. Hawman
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA (A.J.J.)
| | - Mark T. Heise
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Nathaniel J. Moorman
- Department of Microbiology & Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Thomas E. Morrison
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA (A.J.J.)
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Hodoameda P, Ebel GD, Mukhopadhyay S, Clem RJ. Extreme infectious titer variability in individual Aedes aegypti mosquitoes infected with Sindbis virus is associated with both differences in virus population structure and dramatic disparities in specific infectivity. PLoS Pathog 2024; 20:e1012047. [PMID: 38412195 PMCID: PMC10923411 DOI: 10.1371/journal.ppat.1012047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 03/08/2024] [Accepted: 02/13/2024] [Indexed: 02/29/2024] Open
Abstract
Variability in how individuals respond to pathogens is a hallmark of infectious disease, yet the basis for individual variation in host response is often poorly understood. The titer of infectious virus among individual mosquitoes infected with arboviruses is frequently observed to vary by several orders of magnitude in a single experiment, even when the mosquitoes are highly inbred. To better understand the basis for this titer variation, we sequenced populations of Sindbis virus (SINV) obtained from individual infected Aedes aegypti mosquitoes that, despite being from a highly inbred laboratory colony, differed in their titers of infectious virus by approximately 10,000-fold. We observed genetic differences between these virus populations that indicated the virus present in the midguts of low titer mosquitoes was less fit than that of high titer mosquitoes, possibly due to founder effects that occurred during midgut infection. Furthermore, we found dramatic differences in the specific infectivity or SI (the ratio of infectious units/viral genome equivalents) between these virus populations, with the SI of low titer mosquitoes being up to 10,000-fold lower than that of high titer mosquitoes. Despite having similar amounts of viral genomes, low titer mosquitoes appeared to contain less viral particles, suggesting that viral genomes were packaged into virions less efficiently than in high titer mosquitoes. Finally, antibiotic treatment, which has been shown to suppress mosquito antiviral immunity, caused an increase in SI. Our results indicate that the extreme variation that is observed in SINV infectious titer between individual Ae. aegypti mosquitoes is due to both genetic differences between virus populations and to differences in the proportion of genomes that are packaged into infectious particles.
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Affiliation(s)
- Peter Hodoameda
- Division of Biology, Kansas State University, Manhattan, Kansas United States of America
| | - Gregory D. Ebel
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado United States of America
| | - Suchetana Mukhopadhyay
- Department of Biology, Indiana University, Bloomington, Indiana United States of America
| | - Rollie J. Clem
- Division of Biology, Kansas State University, Manhattan, Kansas United States of America
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Modahl CM, Chowdhury A, Low DHW, Manuel MC, Missé D, Kini RM, Mendenhall IH, Pompon J. Midgut transcriptomic responses to dengue and chikungunya viruses in the vectors Aedes albopictus and Aedes malayensis. Sci Rep 2023; 13:11271. [PMID: 37438463 DOI: 10.1038/s41598-023-38354-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 07/06/2023] [Indexed: 07/14/2023] Open
Abstract
Dengue (DENV) and chikungunya (CHIKV) viruses are among the most preponderant arboviruses. Although primarily transmitted through the bite of Aedes aegypti mosquitoes, Aedes albopictus and Aedes malayensis are competent vectors and have an impact on arbovirus epidemiology. Here, to fill the gap in our understanding of the molecular interactions between secondary vectors and arboviruses, we used transcriptomics to profile the whole-genome responses of A. albopictus to CHIKV and of A. malayensis to CHIKV and DENV at 1 and 4 days post-infection (dpi) in midguts. In A. albopictus, 1793 and 339 genes were significantly regulated by CHIKV at 1 and 4 dpi, respectively. In A. malayensis, 943 and 222 genes upon CHIKV infection, and 74 and 69 genes upon DENV infection were significantly regulated at 1 and 4 dpi, respectively. We reported 81 genes that were consistently differentially regulated in all the CHIKV-infected conditions, identifying a CHIKV-induced signature. We identified expressed immune genes in both mosquito species, using a de novo assembled midgut transcriptome for A. malayensis, and described the immune architectures. We found the JNK pathway activated in all conditions, generalizing its antiviral function to Aedines. Our comprehensive study provides insight into arbovirus transmission by multiple Aedes vectors.
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Affiliation(s)
- Cassandra M Modahl
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Liverpool School of Tropical Medicine, Liverpool, U.K
| | - Avisha Chowdhury
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Toronto Centre for Liver Disease, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Canada
| | - Dolyce H W Low
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
| | - Menchie C Manuel
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
| | - Dorothée Missé
- MIVEGEC, Univ. Montpellier, IRD, CNRS, Montpellier, France
| | - R Manjunatha Kini
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Ian H Mendenhall
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
| | - Julien Pompon
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore.
- MIVEGEC, Univ. Montpellier, IRD, CNRS, Montpellier, France.
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Fu JYL, Chua CL, Abu Bakar AS, Vythilingam I, Wan Sulaiman WY, Alphey L, Chan YF, Sam IC. Susceptibility of Aedes albopictus, Ae. aegypti and human populations to Ross River virus in Kuala Lumpur, Malaysia. PLoS Negl Trop Dis 2023; 17:e0011423. [PMID: 37307291 DOI: 10.1371/journal.pntd.0011423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 05/28/2023] [Indexed: 06/14/2023] Open
Abstract
BACKGROUND Emerging arboviruses such as chikungunya and Zika viruses have unexpectedly caused widespread outbreaks in tropical and subtropical regions recently. Ross River virus (RRV) is endemic in Australia and has epidemic potential. In Malaysia, Aedes mosquitoes are abundant and drive dengue and chikungunya outbreaks. We assessed risk of an RRV outbreak in Kuala Lumpur, Malaysia by determining vector competence of local Aedes mosquitoes and local seroprevalence as a proxy of human population susceptibility. METHODOLOGY/PRINCIPAL FINDINGS We assessed oral susceptibility of Malaysian Ae. aegypti and Ae. albopictus by real-time PCR to an Australian RRV strain SW2089. Replication kinetics in midgut, head and saliva were determined at 3 and 10 days post-infection (dpi). With a 3 log10 PFU/ml blood meal, infection rate was higher in Ae. albopictus (60%) than Ae. aegypti (15%; p<0.05). Despite similar infection rates at 5 and 7 log10 PFU/ml blood meals, Ae. albopictus had significantly higher viral loads and required a significantly lower median oral infectious dose (2.7 log10 PFU/ml) than Ae. aegypti (4.2 log10 PFU/ml). Ae. albopictus showed higher vector competence, with higher viral loads in heads and saliva, and higher transmission rate (RRV present in saliva) of 100% at 10 dpi, than Ae. aegypti (41%). Ae. aegypti demonstrated greater barriers at either midgut escape or salivary gland infection, and salivary gland escape. We then assessed seropositivity against RRV among 240 Kuala Lumpur inpatients using plaque reduction neutralization, and found a low rate of 0.8%. CONCLUSIONS/SIGNIFICANCE Both Ae. aegypti and Ae. albopictus are susceptible to RRV, but Ae. albopictus displays greater vector competence. Extensive travel links with Australia, abundant Aedes vectors, and low population immunity places Kuala Lumpur, Malaysia at risk of an imported RRV outbreak. Surveillance and increased diagnostic awareness and capacity are imperative to prevent establishment of new arboviruses in Malaysia.
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Affiliation(s)
- Jolene Yin Ling Fu
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Chong Long Chua
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | | | - Indra Vythilingam
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | | | - Luke Alphey
- Arthropod Genetics Group, The Pirbright Institute, Woking, United Kingdom
| | - Yoke Fun Chan
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - I-Ching Sam
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
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van Bree JWM, Linthout C, van Dijk T, Abbo SR, Fros JJ, Koenraadt CJM, Pijlman GP, Wang H. Competition between two Usutu virus isolates in cell culture and in the common house mosquito Culex pipiens. Front Microbiol 2023; 14:1195621. [PMID: 37293213 PMCID: PMC10244747 DOI: 10.3389/fmicb.2023.1195621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 04/18/2023] [Indexed: 06/10/2023] Open
Abstract
Usutu virus (USUV) is a mosquito-borne flavivirus of African origin. Over the past decades, USUV has spread through Europe causing mass die-offs among multiple bird species. The natural transmission cycle of USUV involves Culex spp. mosquitoes as vectors and birds as amplifying hosts. Next to birds and mosquitoes, USUV has also been isolated from multiple mammalian species, including humans, which are considered dead-end hosts. USUV isolates are phylogenetically classified into an African and European branch, subdivided into eight genetic lineages (Africa 1, 2, and 3 and Europe 1, 2, 3, 4, and 5 lineages). Currently, multiple African and European lineages are co-circulating in Europe. Despite increased knowledge of the epidemiology and pathogenicity of the different lineages, the effects of co-infection and transmission efficacy of the co-circulating USUV strains remain unclear. In this study, we report a comparative study between two USUV isolates as follows: a Dutch isolate (USUV-NL, Africa lineage 3) and an Italian isolate (USUV-IT, Europe lineage 2). Upon co-infection, USUV-NL was consistently outcompeted by USUV-IT in mosquito, mammalian, and avian cell lines. In mosquito cells, the fitness advantage of USUV-IT was most prominently observed in comparison to the mammalian or avian cell lines. When Culex pipiens mosquitoes were orally infected with the different isolates, no overall differences in vector competence for USUV-IT and USUV-NL were observed. However, during the in vivo co-infection assay, it was observed that USUV-NL infectivity and transmission were negatively affected by USUV-IT but not vice versa.
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Affiliation(s)
- Joyce W. M. van Bree
- Laboratory of Virology, Wageningen University and Research, Wageningen, Netherlands
| | - Charlotte Linthout
- Laboratory of Entomology, Wageningen University and Research, Wageningen, Netherlands
| | - Teije van Dijk
- Laboratory of Virology, Wageningen University and Research, Wageningen, Netherlands
| | - Sandra R. Abbo
- Laboratory of Virology, Wageningen University and Research, Wageningen, Netherlands
| | - Jelke J. Fros
- Laboratory of Virology, Wageningen University and Research, Wageningen, Netherlands
| | | | - Gorben P. Pijlman
- Laboratory of Virology, Wageningen University and Research, Wageningen, Netherlands
| | - Haidong Wang
- Laboratory of Virology, Wageningen University and Research, Wageningen, Netherlands
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Bardossy ES, Volpe S, Alvarez DE, Filomatori CV. A conserved Y-shaped RNA structure in the 3'UTR of chikungunya virus genome as a host-specialized element that modulates viral replication and evolution. PLoS Pathog 2023; 19:e1011352. [PMID: 37126493 PMCID: PMC10174580 DOI: 10.1371/journal.ppat.1011352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 05/11/2023] [Accepted: 04/11/2023] [Indexed: 05/02/2023] Open
Abstract
RNA viral genomes compact information into functional RNA structures. Here, using chikungunya virus as a model, we investigated the structural requirements of conserved RNA elements in the 3' untranslated region (3'UTR) for viral replication in mosquito and mammalian cells. Using structural predictions and co-variation analysis, we identified a highly stable and conserved Y-shaped structure (SLY) at the end of the 3'UTR that is duplicated in the Asian lineage. Functional studies with mutant viruses showed that the SLY has host-specific functions during viral replication and evolution. The SLY positively modulates viral replication in mosquito cells but has the opposite effect in mammalian cells. Additional structural/functional analyses showed that maintaining the Y-shaped fold and specific nucleotides in the loop are critical for full SLY functionality and optimal viral replication in mosquito cells. Experimental adaptation of viruses with duplicated SLYs to mammalian cells resulted in the generation of heterogeneous viral populations comprising variants with diverse 3'UTRs, contrasting with the homogeneous populations from viruses without SLY copies. Altogether, our findings constitute the first evidence of an RNA secondary structure in the 3'UTR of chikungunya virus genome that plays host-dependent functions.
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Affiliation(s)
- Eugenia Soledad Bardossy
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín-CONICET, Buenos Aires, Argentina
- Escuela de Bio y Nanotecnología, Universidad de San Martín, Buenos Aires, Argentina
| | - Sebastiano Volpe
- Escuela de Bio y Nanotecnología, Universidad de San Martín, Buenos Aires, Argentina
| | - Diego Ezequiel Alvarez
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín-CONICET, Buenos Aires, Argentina
- Escuela de Bio y Nanotecnología, Universidad de San Martín, Buenos Aires, Argentina
| | - Claudia Verónica Filomatori
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín-CONICET, Buenos Aires, Argentina
- Escuela de Bio y Nanotecnología, Universidad de San Martín, Buenos Aires, Argentina
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9
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Factors Affecting Arbovirus Midgut Escape in Mosquitoes. Pathogens 2023; 12:pathogens12020220. [PMID: 36839492 PMCID: PMC9963182 DOI: 10.3390/pathogens12020220] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/25/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023] Open
Abstract
Arboviral diseases spread by mosquitoes cause significant morbidity and mortality throughout much of the world. The treatment and prevention of these diseases through medication and vaccination is often limited, which makes controlling arboviruses at the level of the vector ideal. One way to prevent the spread of an arbovirus would be to stop its vector from developing a disseminated infection, which is required for the virus to make its way to the saliva of the mosquito to be potentially transmitted to a new host. The midgut of the mosquito provides one such opportunity to stop an arbovirus in its tracks. It has been known for many years that in certain arbovirus-vector combinations, or under certain circumstances, an arbovirus can infect and replicate in the midgut but is unable to escape from the tissue to cause disseminated infection. This situation is known as a midgut escape barrier. If we better understand why this barrier occurs, it might aid in the development of more informed control strategies. In this review, we discuss how the midgut escape barrier contributes to virus-vector specificity and possible mechanisms that may allow this barrier to be overcome in successful virus-vector combinations. We also discuss several of the known factors that either increase or decrease the likelihood of midgut escape.
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10
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Heinig-Hartberger M, Hellhammer F, Zöller DDJA, Dornbusch S, Bergmann S, Vocadlova K, Junglen S, Stern M, Lee KZ, Becker SC. Culex Y Virus: A Native Virus of Culex Species Characterized In Vivo. Viruses 2023; 15:235. [PMID: 36680275 PMCID: PMC9863036 DOI: 10.3390/v15010235] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/06/2023] [Accepted: 01/11/2023] [Indexed: 01/17/2023] Open
Abstract
Mosquitoes are vectors of various pathogens that cause diseases in humans and animals. To prevent the outbreak of mosquito-borne diseases, it is essential to control vector populations, as treatment or vaccination for mosquito-borne diseases are often unavailable. Insect-specific viruses (ISVs) have previously been described as being potentially helpful against arboviral disease outbreaks. In this study, we present the first in vivo characterization of the ISV Culex Y virus (CYV). CYV was first isolated from free-living Culex pipiens mosquitoes in 2010; then, it was found in several mosquito cell lines in a further study in 2018. For mammalian cells, we were able to confirm that CYV does not replicate as it was previously described. Additionally, we found that CYV does not replicate in honey bees or locusts. However, we detected replication in the Culex pipiens biotype molestus, Aedes albopictus, and Drosophila melanogaster, thus indicating dipteran specificity. We detected significantly higher mortality in Culex pipiens biotype molestus males and Drosophila melanogaster, but not in Aedes albopictus and female Culex pipiens biotype molestus. CYV could not be transmitted transovarially to offspring, but we detected venereal transmission as well as CYV in mosquitos' saliva, indicating that an oral route of infection would also be possible. CYV's dipteran specificity, transmission routes, and killing effect with respect to Culex males may be used as powerful tools with which to destabilize arbovirus vector populations in the future.
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Affiliation(s)
- Mareike Heinig-Hartberger
- Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - Fanny Hellhammer
- Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - David D. J. A. Zöller
- Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - Susann Dornbusch
- Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - Stella Bergmann
- Institute for Physiology and Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173 Hannover, Germany
| | - Katerina Vocadlova
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Ohlebergsweg 12, 35392 Giessen, Germany
| | - Sandra Junglen
- Institute of Virology, Charité Universitätsmedizin Berlin, Corporate Member of Free University Berlin, Humboldt-University Berlin, and Berlin Institute of Health, Chariteplatz 1, 10117 Berlin, Germany
| | - Michael Stern
- Institute for Physiology and Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173 Hannover, Germany
| | - Kwang-Zin Lee
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Ohlebergsweg 12, 35392 Giessen, Germany
| | - Stefanie C. Becker
- Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany
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11
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Cardoso-Jaime V, Tikhe CV, Dong S, Dimopoulos G. The Role of Mosquito Hemocytes in Viral Infections. Viruses 2022; 14:v14102088. [PMID: 36298644 PMCID: PMC9608948 DOI: 10.3390/v14102088] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/03/2022] [Accepted: 09/13/2022] [Indexed: 11/16/2022] Open
Abstract
Insect hemocytes are the only immune cells that can mount a humoral and cellular immune response. Despite the critical involvement of hemocytes in immune responses against bacteria, fungi, and parasites in mosquitoes, our understanding of their antiviral potential is still limited. It has been shown that hemocytes express humoral factors such as TEP1, PPO, and certain antimicrobial peptides that are known to restrict viral infections. Insect hemocytes also harbor the major immune pathways, such as JAK/STAT, TOLL, IMD, and RNAi, which are critical for the control of viral infection. Recent research has indicated a role for hemocytes in the regulation of viral infection through RNA interference and autophagy; however, the specific mechanism by which this regulation occurs remains uncharacterized. Conversely, some studies have suggested that hemocytes act as agonists of arboviral infection because they lack basal lamina and circulate throughout the whole mosquito, likely facilitating viral dissemination to other tissues such as salivary glands. In addition, hemocytes produce arbovirus agonist factors such as lectins, which enhance viral infection. Here, we summarize our current understanding of hemocytes’ involvement in viral infections.
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Balestrino F, Bouyer J, Vreysen MJB, Veronesi E. Impact of Irradiation on Vector Competence of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) for Dengue and Chikungunya Viruses. Front Bioeng Biotechnol 2022; 10:876400. [PMID: 35721847 PMCID: PMC9204086 DOI: 10.3389/fbioe.2022.876400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
Effective control strategies against arthropod disease vectors are amongst the most powerful tools to prevent the spread of vector-borne diseases. The sterile insect technique (SIT) is an effective and sustainable autocidal control method that has recently shown effective population suppression against different Aedes vector species worldwide. The SIT approach for mosquito vectors requires the release of radio-sterilized male mosquitoes only, but currently available sex separation techniques cannot ensure the complete elimination of females resulting in short-term risk of increased biting rate and arboviral disease transmission. In this study, we compared for the first time the transmission of dengue and chikungunya viruses in Aedes aegypti and Aedes albopictus females exposed as pupae to an irradiation dose of 40 Gy. Females of both species were fed on blood spiked with either dengue or chikungunya viruses, and body parts were tested for virus presence by real-time RT-PCR at different time points. No differences were observed in the dissemination efficiency of the dengue virus in irradiated and unirradiated Ae. albopictus and Ae. aegypti mosquitoes. The dissemination of the chikungunya virus was higher in Ae. albopictus than in Ae. Aegypti, and irradiation increased the virus load in both species. However, we did not observe differences in the transmission efficiency for chikungunya (100%) and dengue (8–27%) between mosquito species, and irradiation did not impact transmissibility. Further implications of these results on the epidemiology of vector-borne diseases in the field are discussed.
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Affiliation(s)
- Fabrizio Balestrino
- National Centre for Vector Entomology, Vetsuisse Faculty, Institute of Parasitology, University of Zürich, Zürich, Switzerland
- Centro Agricoltura Ambiente “G. Nicoli”, Sanitary Entomology and Zoology Department, Crevalcore, Italy
- *Correspondence: Fabrizio Balestrino,
| | - Jérémy Bouyer
- CIRAD, UMR ASTRE CIRAD-INRA « Animals, Health, Territories, Risks and Ecosystems », Montpellier, France
- FAO/IAEA Insect Pest Control Laboratory (IPCL), FAO/IAEA Joint Division of Nuclear Techniques in Food and Agriculture (NAFA), FAO/IAEA Agriculture and Biotechnology Laboratories, Vienna, Austria
| | - Marc J. B. Vreysen
- FAO/IAEA Insect Pest Control Laboratory (IPCL), FAO/IAEA Joint Division of Nuclear Techniques in Food and Agriculture (NAFA), FAO/IAEA Agriculture and Biotechnology Laboratories, Vienna, Austria
| | - Eva Veronesi
- National Centre for Vector Entomology, Vetsuisse Faculty, Institute of Parasitology, University of Zürich, Zürich, Switzerland
- Laboratory of Applied Microbiology, Department of Environment, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Bellinzona, Switzerland
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13
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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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Investigation of Biological Factors Contributing to Individual Variation in Viral Titer after Oral Infection of Aedes aegypti Mosquitoes by Sindbis Virus. Viruses 2022; 14:v14010131. [PMID: 35062335 PMCID: PMC8780610 DOI: 10.3390/v14010131] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/06/2022] [Accepted: 01/07/2022] [Indexed: 12/21/2022] Open
Abstract
The mechanisms involved in determining arbovirus vector competence, or the ability of an arbovirus to infect and be transmitted by an arthropod vector, are still incompletely understood. It is well known that vector competence for a particular arbovirus can vary widely among different populations of a mosquito species, which is generally attributed to genetic differences between populations. What is less understood is the considerable variability (up to several logs) that is routinely observed in the virus titer between individual mosquitoes in a single experiment, even in mosquitoes from highly inbred lines. This extreme degree of variation in the virus titer between individual mosquitoes has been largely ignored in past studies. We investigated which biological factors can affect titer variation between individual mosquitoes of a laboratory strain of Aedes aegypti, the Orlando strain, after Sindbis virus infection. Greater titer variation was observed after oral versus intrathoracic infection, suggesting that the midgut barrier contributes to titer variability. Among the other factors tested, only the length of the incubation period affected the degree of titer variability, while virus strain, mosquito strain, mosquito age, mosquito weight, amount of blood ingested, and virus concentration in the blood meal had no discernible effect. We also observed differences in culture adaptability and in the ability to orally infect mosquitoes between virus populations obtained from low and high titer mosquitoes, suggesting that founder effects may affect the virus titer in individual mosquitoes, although other explanations also remain possible.
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15
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Pawęska JT, Jansen van Vuren P, Storm N, Markotter W, Kemp A. Vector Competence of Eucampsipoda africana (Diptera: Nycteribiidae) for Marburg Virus Transmission in Rousettus aegyptiacus (Chiroptera: Pteropodidae). Viruses 2021; 13:2226. [PMID: 34835032 PMCID: PMC8624361 DOI: 10.3390/v13112226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/26/2021] [Accepted: 10/28/2021] [Indexed: 12/04/2022] Open
Abstract
This study aimed to determine the vector competence of bat-associated nycteribiid flies (Eucamsipoda africana) for Marburg virus (MARV) in the Egyptian Rousette Bat (ERB), Rousettus aegyptiacus. In flies fed on subcutaneously infected ERBs and tested from 3 to 43 days post infection (dpi), MARV was detected only in those that took blood during the peak of viremia, 5-7 dpi. Seroconversion did not occur in control bats in contact with MARV-infected bats infested with bat flies up to 43 days post exposure. In flies inoculated intra-coelomically with MARV and tested on days 0-29 post inoculation, only those assayed on day 0 and day 7 after inoculation were positive by q-RT-PCR, but the virus concentration was consistent with that of the inoculum. Bats remained MARV-seronegative up to 38 days after infestation and exposure to inoculated flies. The first filial generation pupae and flies collected at different times during the experiments were all negative by q-RT-PCR. Of 1693 nycteribiid flies collected from a wild ERB colony in Mahune Cave, South Africa where the enzootic transmission of MARV occurs, only one (0.06%) tested positive for the presence of MARV RNA. Our findings seem to demonstrate that bat flies do not play a significant role in the transmission and enzootic maintenance of MARV. However, ERBs eat nycteribiid flies; thus, the mechanical transmission of the virus through the exposure of damaged mucous membranes and/or skin to flies engorged with contaminated blood cannot be ruled out.
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Affiliation(s)
- Janusz T. Pawęska
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham 2131, South Africa; (P.J.v.V.); (N.S.); (A.K.)
- Centre for Viral Zoonoses, Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa;
- School of Pathology, Faculty of Health Sciences, University of Witwatersrand, Johannesburg 2050, South Africa
| | - Petrus Jansen van Vuren
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham 2131, South Africa; (P.J.v.V.); (N.S.); (A.K.)
- Australian Centre for Disease Preparedness, CSIRO Health & Biosecurity, Geelong, VIC 3220, Australia
| | - Nadia Storm
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham 2131, South Africa; (P.J.v.V.); (N.S.); (A.K.)
- Department of Microbiology, School of Medicine, Boston University, Boston, MA 02118, USA
| | - Wanda Markotter
- Centre for Viral Zoonoses, Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa;
| | - Alan Kemp
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham 2131, South Africa; (P.J.v.V.); (N.S.); (A.K.)
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16
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Infection of Aedes aegypti Mosquitoes with Midgut-Attenuated Sindbis Virus Reduces, but Does Not Eliminate, Disseminated Infection. J Virol 2021; 95:e0013621. [PMID: 33853958 DOI: 10.1128/jvi.00136-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Arboviruses are transmitted by specific vectors, and the reasons for this specificity are not fully understood. One contributing factor is the existence of tissue barriers within the vector such as the midgut escape barrier. We used microRNA (miRNA) targeting of Sindbis virus (SINV) to study how replication in midgut cells contributes to overcoming this barrier in the mosquito Aedes aegypti. SINV constructs were designed to be attenuated specifically in midgut cells by inserting binding sites for midgut-specific miRNAs into either the 3' untranslated region (MRE3'miRT) or the structural open reading frame (MRE-ORFmiRT) of the SINV genome. Both miRNA-targeted viruses replicated less efficiently than control viruses in the presence of these miRNAs. When mosquitoes were given infectious blood meals containing miRNA-targeted viruses, only around 20% (MRE3'miRT) or 40% (MRE-ORFmiRT) of mosquitoes developed disseminated infection. In contrast, dissemination occurred in almost all mosquitoes fed control viruses. Deep sequencing of virus populations from individual mosquitoes ruled out selection for mutations in the inserted target sequences as the cause for dissemination in these mosquitoes. In mosquitoes that became infected with miRNA-targeted viruses, titers were equivalent to those of mosquitoes infected with control virus in both the midgut and the carcass, and there was no evidence of a threshold titer necessary for dissemination. Instead, it appeared that if infection was successfully established in the midgut, replication and dissemination were largely normal. Our results support the hypothesis that replication is an important factor in allowing SINV to overcome the midgut escape barrier but hint that other factors are also likely involved. IMPORTANCE When a mosquito ingests an arbovirus during a blood meal, the arbovirus must escape from the midgut of the vector and infect the salivary glands in order to be transmitted to a new host. We used tissue-specific miRNA targeting to examine the requirement for Sindbis virus (SINV) to replicate in midgut epithelium in order to cause disseminated infection in the mosquito Aedes aegypti. Our results indicate that specifically reducing the ability of SINV to replicate in the mosquito midgut reduces its overall ability to establish infection in the mosquito, but if infection is established, replication and dissemination occur normally. These results are consistent with an importance for replication in the midgut epithelium in aiding arboviruses in crossing the midgut barrier.
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Trammell CE, Goodman AG. Host Factors That Control Mosquito-Borne Viral Infections in Humans and Their Vector. Viruses 2021; 13:v13050748. [PMID: 33923307 PMCID: PMC8145797 DOI: 10.3390/v13050748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/13/2021] [Accepted: 04/22/2021] [Indexed: 02/07/2023] Open
Abstract
Mosquito-borne viral infections are responsible for a significant degree of morbidity and mortality across the globe due to the severe diseases these infections cause, and they continue to increase each year. These viruses are dependent on the mosquito vector as the primary means of transmission to new vertebrate hosts including avian, livestock, and human populations. Due to the dynamic host environments that mosquito-borne viruses pass through as they are transmitted between vector and vertebrate hosts, there are various host factors that control the response to infection over the course of the pathogen's life cycle. In this review, we discuss these host factors that are present in either vector or vertebrate models during infection, how they vary or are conserved between hosts, and their implications in future research pertaining to disease prevention and treatment.
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Affiliation(s)
- Chasity E. Trammell
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99163, USA;
- NIH Protein Biotechnology Training Program, Washington State University, Pullman, WA 99164-6240, USA
| | - Alan G. Goodman
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99163, USA;
- Paul G. Allen School for Global Health, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
- Correspondence: ; Tel.: +1-(509)-335-0186
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18
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Karliuk Y, Vom Hemdt A, Wieseler J, Pfeffer M, Kümmerer BM. Characterization and Vector Competence Studies of Chikungunya Virus Lacking Repetitive Motifs in the 3' Untranslated Region of the Genome. Viruses 2021; 13:v13030403. [PMID: 33806267 PMCID: PMC7999577 DOI: 10.3390/v13030403] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/26/2021] [Accepted: 02/27/2021] [Indexed: 12/27/2022] Open
Abstract
Using reverse genetics, we analyzed a chikungunya virus (CHIKV) isolate of the Indian Ocean lineage lacking direct repeat (DR) elements in the 3′ untranslated region, namely DR1a and DR2a. While this deletion mutant CHIKV-∆DR exhibited growth characteristics comparable to the wild-type virus in Baby Hamster Kidney cells, replication of the mutant was reduced in Aedes albopictus C6/36 and Ae. aegypti Aag2 cells. Using oral and intrathoracic infection of mosquitoes, viral infectivity, dissemination, and transmission of CHIKV-∆DR could be shown for the well-known CHIKV vectors Ae. aegypti and Ae. albopictus. Oral infection of Ae. vexans and Culex pipiens mosquitoes with mutant or wild-type CHIKV showed very limited infectivity. Dissemination, transmission, and transmission efficiencies as determined via viral RNA in the saliva were slightly higher in Ae. vexans for the wild-type virus than for CHIKV-∆DR. However, both Ae. vexans and Cx. pipiens allowed efficient viral replication after intrathoracic injection confirming that the midgut barrier is an important determinant for the compromised infectivity after oral infection. Transmission efficiencies were neither significantly different between Ae. vexans and Cx. pipiens nor between wild-type and CHIKV-∆DR. With a combined transmission efficiency of 6%, both Ae. vexans and Cx. pipiens might serve as potential vectors in temperate regions.
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Affiliation(s)
- Yauhen Karliuk
- Institute of Animal Hygiene and Veterinary Public Health, Faculty of Veterinary Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Anja Vom Hemdt
- Institute of Virology, Medical Faculty, University of Bonn, 53127 Bonn, Germany
| | - Janett Wieseler
- Institute of Virology, Medical Faculty, University of Bonn, 53127 Bonn, Germany
| | - Martin Pfeffer
- Institute of Animal Hygiene and Veterinary Public Health, Faculty of Veterinary Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Beate M Kümmerer
- Institute of Virology, Medical Faculty, University of Bonn, 53127 Bonn, Germany
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