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Barillas-Mury C, Ribeiro JMC, Valenzuela JG. Understanding pathogen survival and transmission by arthropod vectors to prevent human disease. Science 2022; 377:eabc2757. [PMID: 36173836 DOI: 10.1126/science.abc2757] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Many endemic poverty-associated diseases, such as malaria and leishmaniasis, are transmitted by arthropod vectors. Pathogens must interact with specific molecules in the vector gut, the microbiota, and the vector immune system to survive and be transmitted. The vertebrate host, in turn, is infected when the pathogen and vector-derived factors, such as salivary proteins, are delivered into the skin by a vector bite. Here, we review recent progress in our understanding of the biology of pathogen transmission from the human to the vector and back, from the vector to the host. We also highlight recent advances in the biology of vector-borne disease transmission, which have translated into additional strategies to prevent human disease by either reducing vector populations or by disrupting their ability to transmit pathogens.
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Affiliation(s)
- Carolina Barillas-Mury
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852, USA
| | - José M C Ribeiro
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852, USA
| | - Jesus G Valenzuela
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852, USA
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Saingamsook J, Yanola J, Lumjuan N, Walton C, Somboon P. Investigation of Relative Development and Reproductivity Fitness Cost in Three Insecticide-Resistant Strains of Aedes aegypti from Thailand. INSECTS 2019; 10:insects10090265. [PMID: 31443487 PMCID: PMC6780153 DOI: 10.3390/insects10090265] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/16/2019] [Accepted: 08/19/2019] [Indexed: 02/05/2023]
Abstract
Knockdown resistance (kdr) and detoxification enzymes are major resistance mechanisms in insecticide-resistant Aedes aegypti throughout the world. Persistence of the resistance phenotype is associated with high fitness of resistance alleles in the absence of insecticide pressure. This study determined the relative fitness cost of three insecticide-resistant strains of Aedes aegypti—PMD, PMD-R, and UPK-R—and a hybrid under similar laboratory conditions in the absence of insecticide. The PMD strain is resistant to DDT with no kdr alleles; the PMD-R is resistant to DDT and permethrin with 1534C homozygous kdr alleles; and UPK-R is resistant to DDT, permethrin, and deltamethrin with 989P + 1016G homozygous alleles. The DDT-resistant PMD strain had the highest fitness compared with the two DDT/pyrethroid-resistant strains (PMD-R and UPK-R) and hybrid. Consistent fitness costs were observed in the DDT/pyrethroid-resistant strains and hybrid, including shorter wing length, reduced egg hatchability, shorter female lifespan, and shorter viability of eggs after storage, whereas no effect was observed on blood feeding rate. In addition, reduced egg production was observed in the PMD-R strain and prolonged developmental time was seen in the UPK-R strain. The corresponding hybrid that is heterozygous for kdr alleles was fitter than either of the homozygous mutant genotypes. This is in accordance with the high frequency of heterozygous genotypes observed in natural populations of Ae. aegypti in Chiang Mai city.
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Affiliation(s)
- Jassada Saingamsook
- Center of Insect Vector Study, Department of Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
- Graduate PhD's Degree Program in Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Jintana Yanola
- Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Nongkran Lumjuan
- Research Institute for Health Sciences, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Catherine Walton
- School of Earth and Environmental Sciences, Faculty of Science and Engineering, University of Manchester, Manchester M13 9PL, UK
| | - Pradya Somboon
- Center of Insect Vector Study, Department of Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand.
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Contreras M, Villar M, de la Fuente J. A Vaccinomics Approach for the Identification of Tick Protective Antigens for the Control of Ixodes ricinus and Dermacentor reticulatus Infestations in Companion Animals. Front Physiol 2019; 10:977. [PMID: 31417430 PMCID: PMC6681794 DOI: 10.3389/fphys.2019.00977] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 07/11/2019] [Indexed: 01/10/2023] Open
Abstract
Ticks and tick-borne pathogens affect health and welfare of companion animals worldwide, and some human tick-borne diseases are associated with exposure to domestic animals. Vaccines are the most environmentally friendly alternative to acaracides for the control of tick infestations, and to reduce the risk for tick-borne diseases affecting human and animal health. However, vaccines have not been developed or successfully implemented for most vector-borne diseases. The main limitation for the development of effective vaccines is the identification of protective antigens. To address this limitation, in this study we used an experimental approach combining vaccinomics based on transcriptomics and proteomics data with vaccination trials for the identification of tick protective antigens. The study was focused on Ixodes ricinus and Dermacentor reticulatus that infest humans, companion animals and other domestic and wild animals, and transmit disease-causing pathogens. Tick larvae and adult salivary glands were selected for analysis to target tick organs and developmental stages playing a key role during tick life cycle and pathogen infection and transmission. Two I. ricinus (heme lipoprotein and uncharacterized secreted protein) and five D. reticulatus (glypican-like protein, secreted protein involved in homophilic cell adhesion, sulfate/anion exchanger, signal peptidase complex subunit 3, and uncharacterized secreted protein) proteins were identified as the most effective protective antigens based on the criteria of vaccine E > 80%. The putative function of selected protective antigens, which are involved in different biological processes, resulted in vaccines affecting multiple tick developmental stages. These results suggested that the combination of some of these antigens might be considered to increase vaccine efficacy through antigen synergy for the control of tick infestations and potentially affecting pathogen infection and transmission. These antigens were proposed for commercial vaccine development for the control of tick infestations in companion animals, and potentially in other hosts for these tick species.
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Affiliation(s)
- Marinela Contreras
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC; CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - Margarita Villar
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC; CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - José de la Fuente
- SaBio, Instituto de Investigación en Recursos Cinegéticos (IREC; CSIC-UCLM-JCCM), Ciudad Real, Spain
- Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK, United States
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Cabezas-Cruz A, Mateos-Hernández L, Pérez-Cruz M, Valdés JJ, Mera IGFD, Villar M, de la Fuente J. Regulation of the Immune Response to α-Gal and Vector-borne Diseases. Trends Parasitol 2015; 31:470-476. [DOI: 10.1016/j.pt.2015.06.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 05/18/2015] [Accepted: 06/24/2015] [Indexed: 11/26/2022]
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Patil PB, Niranjan Reddy BP, Gorman K, Seshu Reddy KV, Barwale SR, Zehr UB, Nimmo D, Naish N, Alphey L. Mating competitiveness and life-table comparisons between transgenic and Indian wild-type Aedes aegypti L. PEST MANAGEMENT SCIENCE 2015; 71:957-65. [PMID: 25078081 PMCID: PMC4657483 DOI: 10.1002/ps.3873] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 07/10/2014] [Accepted: 07/24/2014] [Indexed: 05/23/2023]
Abstract
BACKGROUND OX513A is a genetically engineered strain of Aedes aegypti carrying a repressible, dominantly inherited transgene that confers lethality in immature heterozygous progeny. Released male OX513A adults have proven to be effective for the localised suppression of wild Ae. aegypti, highlighting its potential in vector control. Mating and life-table assessments were used to compare OX513A with reared Ae. aegypti strains collected from New Delhi and Aurangabad regions in India. RESULTS Mating proportions of New Delhi females versus males of OX513A or New Delhi strains were 0.52 and 0.48 respectively, indicating no discrimination by females against either strain, and males of both strains were equally competitive. Developmental time from first instar to adult emergence was significantly longer for OX513A (10.7 ± 0.04 days) than for New Delhi (9.4 ± 0.04 days) and Aurangabad strains (9.1 ± 0.04 days). Differences in mean longevities, female reproductive parameters and population growth parameters between the strains were non-significant. CONCLUSIONS The laboratory study demonstrates that only minor life-table variations of limited biological relevance exist between OX513A and Indian Ae. aegypti populations, and males had equal potential for mating competitiveness. Thus, results support the OX513A strain as a suitable candidate for continued evaluation towards sustainable management of Ae. aegypti populations in India.
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Affiliation(s)
- Prabhakargouda B Patil
- Gangabishan Bhikulal Investment and Trading Limited (GBIT)Jalna, Maharashtra State, India
| | - BP Niranjan Reddy
- Gangabishan Bhikulal Investment and Trading Limited (GBIT)Jalna, Maharashtra State, India
| | | | - KV Seshu Reddy
- Gangabishan Bhikulal Investment and Trading Limited (GBIT)Jalna, Maharashtra State, India
| | - Shirish R Barwale
- Gangabishan Bhikulal Investment and Trading Limited (GBIT)Jalna, Maharashtra State, India
| | - Usha B Zehr
- Gangabishan Bhikulal Investment and Trading Limited (GBIT)Jalna, Maharashtra State, India
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Abstract
Background Sexual dimorphism in animals has been studied from different perspectives for decades. In 1874 Darwin hypothesized that it was related to sexual selection, and even after nearly 140 years, when additional empirical data has become available and the subject has been investigated from a contemporary viewpoint, this idea is still supported. Although mosquito (Culicidae) wings are of great importance as they play a sex-specific role, little is known about wing sexual dimorphism in these pathogen-vector insects. Detection and characterization of wing sexual dimorphism in culicids may indirectly enhance our knowledge of their epidemiology or reveal sex-linked genes, aspects that have been discussed by vector control initiatives and developers of genetically modified mosquitoes. Methods Using geometric morphometrics, we carried out a comparative assessment of wing sexual dimorphism in ten culicid species of medical/veterinary importance from genera Culex, Aedes, Anopheles and Ochlerotatus collected in Brazil. Results Discriminant analysis revealed significant sexual dimorphism in all the species studied, indicating that phenotypic expression of wing shape in mosquitoes is indeed sex-specific. A cross-validated test performed to reclassify the sexes with and without allometry yielded very similar results. Mahalanobis distances among the ten species showed that the species had different patterns of shape sexual dimorphism and that females are larger than males in some species. Conclusion Wing morphology differed significantly between species. The finding of sexual dimorphism in all the species would suggest that the wing geometry of Culicidae is canalized. Although sexual dimorphism is prevalent, species-specific patterns occur. Allometry was not the main determinant of sexual dimorphism, which suggests that sexual selection or other evolutionary mechanisms underlie wing sexual dimorphism in these insects.
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de la Fuente J, Villar M, Contreras M, Moreno-Cid JA, Merino O, Pérez de la Lastra JM, de la Fuente G, Galindo RC. Prospects for vaccination against the ticks of pets and the potential impact on pathogen transmission. Vet Parasitol 2015; 208:26-9. [DOI: 10.1016/j.vetpar.2014.12.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Costa-da-Silva AL, Marinotti O, Ribeiro JMC, Silva MCP, Lopes AR, Barros MS, Sá-Nunes A, Kojin BB, Carvalho E, Suesdek L, Silva-Neto MAC, James AA, Capurro ML. Transcriptome sequencing and developmental regulation of gene expression in Anopheles aquasalis. PLoS Negl Trop Dis 2014; 8:e3005. [PMID: 25033462 PMCID: PMC4102416 DOI: 10.1371/journal.pntd.0003005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 06/02/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Anopheles aquasalis is a major malaria vector in coastal areas of South and Central America where it breeds preferentially in brackish water. This species is very susceptible to Plasmodium vivax and it has been already incriminated as responsible vector in malaria outbreaks. There has been no high-throughput investigation into the sequencing of An. aquasalis genes, transcripts and proteins despite its epidemiological relevance. Here we describe the sequencing, assembly and annotation of the An. aquasalis transcriptome. METHODOLOGY/PRINCIPAL FINDINGS A total of 419 thousand cDNA sequence reads, encompassing 164 million nucleotides, were assembled in 7544 contigs of ≥ 2 sequences, and 1999 singletons. The majority of the An. aquasalis transcripts encode proteins with their closest counterparts in another neotropical malaria vector, An. darlingi. Several analyses in different protein databases were used to annotate and predict the putative functions of the deduced An. aquasalis proteins. Larval and adult-specific transcripts were represented by 121 and 424 contig sequences, respectively. Fifty-one transcripts were only detected in blood-fed females. The data also reveal a list of transcripts up- or down-regulated in adult females after a blood meal. Transcripts associated with immunity, signaling networks and blood feeding and digestion are discussed. CONCLUSIONS/SIGNIFICANCE This study represents the first large-scale effort to sequence the transcriptome of An. aquasalis. It provides valuable information that will facilitate studies on the biology of this species and may lead to novel strategies to reduce malaria transmission on the South American continent. The An. aquasalis transcriptome is accessible at http://exon.niaid.nih.gov/transcriptome/An_aquasalis/Anaquexcel.xlsx.
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Affiliation(s)
- André L. Costa-da-Silva
- Laboratório de Mosquitos Geneticamente Modificados, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, INCT-EM, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Osvaldo Marinotti
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, United States of America
| | - José M. C. Ribeiro
- Section of Vector Biology, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Maria C. P. Silva
- Laboratório de Mosquitos Geneticamente Modificados, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Adriana R. Lopes
- Laboratório de Bioquímica e Biofísica, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Michele S. Barros
- Laboratório de Imunologia Experimental, Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Anderson Sá-Nunes
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, INCT-EM, Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Imunologia Experimental, Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Bianca B. Kojin
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, United States of America
| | - Eneas Carvalho
- Centro de Biotecnologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Lincoln Suesdek
- Laboratório de Mosquitos Geneticamente Modificados, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Mário Alberto C. Silva-Neto
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, INCT-EM, Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Sinalização Celular, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Anthony A. James
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, United States of America
- Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, California, United States of America
| | - Margareth L. Capurro
- Laboratório de Mosquitos Geneticamente Modificados, Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, INCT-EM, Rio de Janeiro, Rio de Janeiro, Brazil
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Carvalho DO, Costa-da-Silva AL, Lees RS, Capurro ML. Two step male release strategy using transgenic mosquito lines to control transmission of vector-borne diseases. Acta Trop 2014; 132 Suppl:S170-7. [PMID: 24513036 DOI: 10.1016/j.actatropica.2013.09.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 09/21/2013] [Accepted: 09/26/2013] [Indexed: 12/27/2022]
Abstract
Mosquitoes are responsible for the transmission of pathogens that cause devastating human diseases such as malaria and dengue. The current increase in mean global temperature and changing sea level interfere with precipitation frequency and some other climatic conditions which, in general, influence the rate of development of insects and etiologic agents causing acceleration as the temperature rises. The most common strategy employed to combat target mosquito species is the Integrated Vector Management (IVM), which comprises the use of multiple activities and various approaches to preventing the spread of a vector in infested areas. IVM programmes are becoming ineffective; and the global scenario is threatening, requiring new interventions for vector control and surveillance. Not surprisingly, there is a growing need to find alternative methods to combat the mosquito vectors. The possibility of using transgenic mosquitoes to fight against those diseases has been discussed over the last two decades and this use of transgenic lines to suppress populations or to replace them is still under investigation through field and laboratory trials. As an alternative, the available transgenic strategies could be improved by coupling suppression and substitution strategies. The idea is to first release a suppression line to significantly reduce the wild population, and once the first objective is reached a second release using a substitution line could be then performed. Examples of targeting this approach against vectors of malaria and dengue are discussed.
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Oliva CF, Damiens D, Benedict MQ. Male reproductive biology of Aedes mosquitoes. Acta Trop 2014; 132 Suppl:S12-9. [PMID: 24308996 DOI: 10.1016/j.actatropica.2013.11.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 11/19/2013] [Accepted: 11/23/2013] [Indexed: 12/27/2022]
Abstract
Among Aedes mosquitoes are species responsible for transmission of serious pathogens to humans. To cope with the current threats to long-term effectiveness of the traditional vector control methods, non-conventional control strategies are being developed. These include autocidal control such as the release of sterile males (sterile insect technique) and the release of Wolbachia-infected males to induce sexual sterility (incompatible insect technique) and pathogen-refractory strain replacement variations using Wolbachia. Sterile male types of techniques particularly depend on released males' ability to successfully mate with wild females. For that reason, a good understanding of male mating biology, including a thorough understanding of the reproductive system and mating capacity, increases the likelihood of success of such genetic vector control programmes. Here we review the literature concerning the reproduction of Aedes mosquitoes with an emphasis on the male biology. We consider sexual maturation, mate finding, insemination, male reproductive capacity, and the occurrence of multiple matings. We also discuss which parameters are of greatest importance for the successful implementation of autocidal control methods and propose questions for future research.
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de la Fuente J, Moreno-Cid JA, Galindo RC, Almazan C, Kocan KM, Merino O, Perez de la Lastra JM, Estrada-Peña A, Blouin EF. Subolesin/Akirin Vaccines for the Control of Arthropod Vectors and Vectorborne Pathogens. Transbound Emerg Dis 2013; 60 Suppl 2:172-8. [DOI: 10.1111/tbed.12146] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Indexed: 12/30/2022]
Affiliation(s)
- J. de la Fuente
- Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM; Ciudad Real Spain
- Department of Veterinary Pathobiology; Center for Veterinary Health Sciences; Oklahoma State University; Stillwater OK USA
| | - J. A. Moreno-Cid
- Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM; Ciudad Real Spain
| | - R. C. Galindo
- Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM; Ciudad Real Spain
| | - C. Almazan
- Facultad de Medicina Veterinaria y Zootecnia; Universidad Autónoma de Tamaulipas; Ciudad Victoria Mexico
| | - K. M. Kocan
- Department of Veterinary Pathobiology; Center for Veterinary Health Sciences; Oklahoma State University; Stillwater OK USA
| | - O. Merino
- Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM; Ciudad Real Spain
| | | | - A. Estrada-Peña
- Department of Parasitology; Veterinary Faculty; Zaragoza Spain
| | - E. F. Blouin
- Department of Veterinary Pathobiology; Center for Veterinary Health Sciences; Oklahoma State University; Stillwater OK USA
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Murdock CC, Moller-Jacobs LL, Thomas MB. Complex environmental drivers of immunity and resistance in malaria mosquitoes. Proc Biol Sci 2013; 280:20132030. [PMID: 24048159 PMCID: PMC3779341 DOI: 10.1098/rspb.2013.2030] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Considerable research effort has been directed at understanding the genetic and molecular basis of mosquito innate immune mechanisms. Whether environmental factors interact with these mechanisms to shape overall resistance remains largely unexplored. Here, we examine how changes in mean ambient temperature, diurnal temperature fluctuation and time of day of infection affected the immunity and resistance of Anopheles stephensi to infection with Escherichia coli. We used quantitative PCR to estimate the gene expression of three immune genes in response to challenge with heat-killed E. coli. We also infected mosquitoes with live E. coli and ran bacterial growth assays to quantify host resistance. Both mosquito immune parameters and resistance were directly affected by mean temperature, diurnal temperature fluctuation and time of day of infection. Furthermore, there was a suite of complex two- and three-way interactions yielding idiosyncratic phenotypic variation under different environmental conditions. The results demonstrate mosquito immunity and resistance to be strongly influenced by a complex interplay of environmental variables, challenging the interpretation of the very many mosquito immune studies conducted under standard laboratory conditions.
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Affiliation(s)
- Courtney C Murdock
- Center for Infectious Disease Dynamics, Department of Entomology, Pennsylvania State University, , Merkle Lab, Orchard Road, University Park, PA 16802, USA
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Dabire KR, Sawadodgo S, Diabate A, Toe KH, Kengne P, Ouari A, Costantini C, Gouagna C, Simard F, Baldet T, Lehmann T, Gibson G. Assortative mating in mixed swarms of the mosquito Anopheles gambiae s.s. M and S molecular forms, in Burkina Faso, West Africa. MEDICAL AND VETERINARY ENTOMOLOGY 2013; 27:298-312. [PMID: 23360106 DOI: 10.1111/j.1365-2915.2012.01049.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The molecular form composition of Anopheles gambiae Giles s.s. (Diptera: Culicidae) mating swarms and the associated mating pairs (copulae) were investigated during two rainy seasons (July to October, 2005 and July to November, 2006) in the villages of Soumousso and Vallée du Kou (VK7). Although the habitats of these villages differ markedly, sympatric populations of M and S molecular forms of An. gambiae s.s. occur in both places periodically. The main aim was to assess the degree to which these molecular forms mate assortatively. In Soumousso, a wooded savannah habitat, the majority of swarm samples consisted of only S-form males (21/28), although a few M-form males were found in mixed M- and S-form swarms. In VK7, a rice growing area, the majority of swarm samples consisted of only M-form males (38/62), until October and November 2006, when there were nearly as many mixed-form as single-form swarms. Overall, ∼60% of M- and S-form swarms were temporally or spatially segregated; the two forms were effectively prevented from encountering each other. Of the remaining 40% of swarms, however, only about half were single-form and the rest were mixed-form. Of the 33 copulae collected from mixed-form swarms, only four were mixed-form pairs, significantly fewer than expected by random pairing between forms (χ(2) = 10.34, d.f. = 2, P < 0.01). Finally, all specimens of inseminated females were of the same form as the sperm contained within their spermatheca (n = 91), even for the four mixed-form copulae. These findings indicate that assortative mating occurs within mixed-form swarms, mediated most probably by close-range mate recognition cues.
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Affiliation(s)
- K R Dabire
- Institut de Recherche en Sciences de la Santé (IRSS), Bobo-Dioulasso, West Africa.
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Havlíková S, Ličková M, Ayllón N, Roller L, Kazimírová M, Slovák M, Moreno-Cid JA, Pérez de la Lastra JM, Klempa B, de la Fuente J. Immunization with recombinant subolesin does not reduce tick infection with tick-borne encephalitis virus nor protect mice against disease. Vaccine 2013; 31:1582-9. [PMID: 23357197 DOI: 10.1016/j.vaccine.2013.01.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 12/26/2012] [Accepted: 01/12/2013] [Indexed: 12/30/2022]
Abstract
Tick-borne encephalitis (TBE) is a growing zoonotic disease caused by tick-borne encephalitis virus (TBEV) infection. Although effective vaccines for TBEV are available, on-going vaccination efforts are insufficient to prevent increase in TBE cases annually. Vaccination with arthropod vector antigens to reduce vector infestations and vector capacity allows control of several vector-borne diseases by targeting their common vector. Subolesin (SUB) is a tick protective antigen that has a role in tick innate immunity and other molecular pathways and has been shown to protect against tick infestations and infection by vector-borne pathogens. However, SUB expression and the effect of SUB immunization have not been evaluated for tick-borne viruses. Herein, we showed that SUB expression is downregulated during Ixodes ricinus tick feeding but induced in ticks infected with TBEV, thus supporting a role for this molecule in tick innate immune response to virus infection. Immunization with recombinant SUB reduced SUB mRNA levels in nymphs co-feeding with infected females and suggested and effect on tick infestations in mice. However, SUB immunization did not reduce tick infection with TBEV nor protect mice against TBE. These results suggested that SUB is not a good candidate antigen for vaccination against TBEV and support the characterization of tick-pathogen interactions to identify mechanisms that could be targeted to reduce TBEV infection and transmission by ticks.
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Affiliation(s)
- Sabína Havlíková
- Institute of Virology, Slovak Academy of Sciences, Dúbravská cesta 9, 84505 Bratislava, Slovakia
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Control of multiple arthropod vector infestations with subolesin/akirin vaccines. Vaccine 2013; 31:1187-96. [PMID: 23291476 DOI: 10.1016/j.vaccine.2012.12.073] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 12/20/2012] [Accepted: 12/23/2012] [Indexed: 11/24/2022]
Abstract
Diseases transmitted by arthropod vectors such as mosquitoes, ticks and sand flies greatly impact human and animal health and thus their control is important for the eradication of vector-borne diseases (VBD). Vaccination is an environmentally friendly alternative for vector control that allows control of several VBD by targeting their common vector. Recent results have suggested that subolesin/akirin (SUB/AKR) is good candidate antigens for the control of arthropod vector infestations. Here we describe the comparative effect of vaccination with SUB, AKR and Q38 and Q41 chimeras containing SUB/AKR conserved protective epitopes on tick, mosquitoes and sand flies vector mortality, molting, oviposition and/or fertility. We demonstrated that SUB vaccination had the highest efficacy (E) across all vector species (54-92%), Q41 vaccination had the highest vaccine E in mosquitoes (99%) by reducing female survival and fertility, and Q38 vaccination had the highest effect on reducing mosquito (28%) and sand fly (26%) oviposition. The effect of vaccination on different developmental processes in several important arthropod vectors encourages the development of SUB/AKR universal vaccines for the control of multiple vector infestations and reduction of VBD.
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16
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Rethinking vector immunology: the role of environmental temperature in shaping resistance. Nat Rev Microbiol 2012; 10:869-76. [PMID: 23147703 DOI: 10.1038/nrmicro2900] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent ecological research has revealed that environmental factors can strongly affect insect immunity and influence the outcome of host-parasite interactions. To date, however, most studies examining immune function in mosquitoes have ignored environmental variability. We argue that one such environmental variable, temperature, influences both vector immunity and the parasite itself. As temperatures in the field can vary greatly from the ambient temperature in the laboratory, it will be essential to take temperature into account when studying vector immunology.
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Murdock CC, Paaijmans KP, Bell AS, King JG, Hillyer JF, Read AF, Thomas MB. Complex effects of temperature on mosquito immune function. Proc Biol Sci 2012; 279:3357-66. [PMID: 22593107 PMCID: PMC3385736 DOI: 10.1098/rspb.2012.0638] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Over the last 20 years, ecological immunology has provided much insight into how environmental factors shape host immunity and host–parasite interactions. Currently, the application of this thinking to the study of mosquito immunology has been limited. Mechanistic investigations are nearly always conducted under one set of conditions, yet vectors and parasites associate in a variable world. We highlight how environmental temperature shapes cellular and humoral immune responses (melanization, phagocytosis and transcription of immune genes) in the malaria vector, Anopheles stephensi. Nitric oxide synthase expression peaked at 30°C, cecropin expression showed no main effect of temperature and humoral melanization, and phagocytosis and defensin expression peaked around 18°C. Further, immune responses did not simply scale with temperature, but showed complex interactions between temperature, time and nature of immune challenge. Thus, immune patterns observed under one set of conditions provide little basis for predicting patterns under even marginally different conditions. These quantitative and qualitative effects of temperature have largely been overlooked in vector biology but have significant implications for extrapolating natural/transgenic resistance mechanisms from laboratory to field and for the efficacy of various vector control tools.
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Affiliation(s)
- C C Murdock
- Department of Entomology, Center for Infectious Disease Dynamics, Merkle Lab, University Park, PA 16802, USA.
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18
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Helinski MEH, Valerio L, Facchinelli L, Scott TW, Ramsey J, Harrington LC. Evidence of polyandry for Aedes aegypti in semifield enclosures. Am J Trop Med Hyg 2012; 86:635-41. [PMID: 22492148 PMCID: PMC3403777 DOI: 10.4269/ajtmh.2012.11-0225] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 12/14/2011] [Indexed: 11/07/2022] Open
Abstract
Female Aedes aegypti are assumed to be primarily monandrous (i.e., mate only once in their lifetime), but true estimates of mating frequency have not been determined outside the laboratory. To assess polyandry in Ae. aegypti with first-generation progeny from wild mosquitoes, stable isotope semen-labeled males ((15)N or (13)C) were allowed to mate with unlabeled females in semifield enclosures (22.5 m(3)) in a dengue-endemic area in southern Mexico. On average, 14% of females were positive for both labels, indicating that they received semen from more than one male. Our results provide evidence of a small but potentially significant rate of multiple mating within a 48-hour period and provide an approach for future open-field studies of polyandry in this species. Polyandry has implications for understanding mosquito ecology, evolution, and reproductive behavior as well as genetic strategies for mosquito control.
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Vidal PO, Suesdek L. Comparison of wing geometry data and genetic data for assessing the population structure of Aedes aegypti. INFECTION GENETICS AND EVOLUTION 2011; 12:591-6. [PMID: 22178147 DOI: 10.1016/j.meegid.2011.11.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Revised: 11/25/2011] [Accepted: 11/28/2011] [Indexed: 12/01/2022]
Abstract
Aedes aegypti is the most important vector of dengue viruses in tropical and subtropical regions. Because vaccines are still under development, dengue prevention depends primarily on vector control. Population genetics is a common approach in research involving Ae. aegypti. In the context of medical entomology, wing morphometric analysis has been proposed as a strong and low-cost complementary tool for investigating population structure. Therefore, we comparatively evaluated the genetic and phenotypic variability of population samples of Ae. aegypti from four sampling sites in the metropolitan area of São Paulo city, Brazil. The distances between the sites ranged from 7.1 to 50 km. This area, where knowledge on the population genetics of this mosquito is incipient, was chosen due to the thousands of dengue cases registered yearly. The analysed loci were polymorphic, and they revealed population structure (global F(ST)=0.062; p<0.05) and low levels of gene flow (Nm=0.47) between the four locations. Principal component and discriminant analyses of wing shape variables (18 landmarks) demonstrated that wing polymorphisms were only slightly more common between populations than within populations. Whereas microsatellites allowed for geographic differentiation, wing geometry failed to distinguish the samples. These data suggest that microevolution in this species may affect genetic and morphological characters to different degrees. In this case, wing shape was not validated as a marker for assessing population structure. According to the interpretation of a previous report, the wing shape of Ae. aegypti does not vary significantly because it is stabilised by selective pressure.
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Affiliation(s)
- Paloma Oliveira Vidal
- Instituto Butantan - Seção Parasitologia, Av. Vital Brazil, 1500 São Paulo, SP, Brazil
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20
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Shin D, Jin L, Lobo NF, Severson DW. Transcript profiling of the meiotic drive phenotype in testis of Aedes aegypti using suppressive subtractive hybridization. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:1220-1226. [PMID: 21708167 PMCID: PMC3167017 DOI: 10.1016/j.jinsphys.2011.05.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 05/20/2011] [Accepted: 05/24/2011] [Indexed: 05/31/2023]
Abstract
The meiotic drive gene in Aedes aegypti is tightly linked with the sex determination locus on chromosome 1, and causes highly male-biased sex ratios. We prepared cDNA libraries from testes from the Ae. aegypti T37 strain (driving) and RED strain (non-driving), and used suppressive subtraction hybridization techniques to enrich for T37 testes-specific transcripts. Expressed sequence tags (ESTs) were obtained from a total of 2784 randomly selected clones from the subtracted T37 (subT37) library as well as the primary libraries for each strain (pT37 and pRED). Sequence analysis identified a total of 171 unique genes in the subT37 library and 299 unique genes among the three libraries. The majority of genes enriched in the subT37 library were associated with signal transduction, development, reproduction, metabolic process and cell cycle functions. Further, as observed with meiotic drive systems in Drosophila and mouse, a number of these genes were associated with signaling cascades that involve the Ras superfamily of regulatory small GTPases. Differential expression of several of these genes was verified in Ae. aegypti pupal testes using qRT-PCR. This study increases our understanding of testes gene expression enriched in adult males from the meiotic drive strain as well as insights into the basic testes transcriptome in Ae. aegypti.
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Affiliation(s)
- Dongyoung Shin
- Eck Institute for Global Health, Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5645, USA.
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21
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de la Fuente J, Moreno-Cid JA, Canales M, Villar M, de la Lastra JMP, Kocan KM, Galindo RC, Almazán C, Blouin EF. Targeting arthropod subolesin/akirin for the development of a universal vaccine for control of vector infestations and pathogen transmission. Vet Parasitol 2011; 181:17-22. [DOI: 10.1016/j.vetpar.2011.04.018] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Helinski MEH, Harrington LC. Male mating history and body size influence female fecundity and longevity of the dengue vector Aedes aegypti. JOURNAL OF MEDICAL ENTOMOLOGY 2011; 48:202-11. [PMID: 21485355 PMCID: PMC4182911 DOI: 10.1603/me10071] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Male reproductive success is dependent on insemination success and reproductive output. During mating, male mosquitoes transfer not just sperm, but also seminal fluid proteins that may have profound effects on mated female biology and behavior. In this study, we investigated the role of male body size and mating history on semen depletion, female longevity, and reproductive success in Aedes aegypti L. Small and large males were mated in rapid succession with up to five females. Our results indicate that large males had greater mating capacity than small males. A reduction in fecundity by >50% was observed in females that were fourth to mate with small males in comparison with females that mated earlier in sequence. For females mated to large males, this reduction became evident for females that mated fifth in sequence. No loss of fertility (measured as hatch rate) was observed in females that were third-fifth in mating sequence compared with females mated to virgin males. When females were maintained on a low-quality (5% sucrose) diet, those mated to virgin males had a greater longevity compared with females mated third in sequence. We conclude that small males experience more rapid seminal depletion than large males, and discuss the role of semen depletion in the mated female. Our results contribute toward a better understanding of the complexity of Ae. aegypti mating biology and provide refined estimates of mating capacity for genetic control efforts.
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23
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Moreno-Cid JA, Jiménez M, Cornelie S, Molina R, Alarcón P, Lacroix MN, Pinal R, Delacour S, Lucientes J, Canales M, de la Lastra JMP, Villar M, de la Fuente J. Characterization of Aedes albopictus akirin for the control of mosquito and sand fly infestations. Vaccine 2010; 29:77-82. [DOI: 10.1016/j.vaccine.2010.10.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 09/24/2010] [Accepted: 10/06/2010] [Indexed: 11/25/2022]
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Benedict M, Eckerstorfer M, Franz G, Gaugitsch H, Greiter A, Heissenberger A, Knols B, Kumschick S, Nentwig W, Rabitsch W. Defining Environment Risk Assessment Criteria for Genetically Modified Insects to be placed on the EU Market. ACTA ACUST UNITED AC 2010. [DOI: 10.2903/sp.efsa.2010.en-71] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Hemme RR, Thomas CL, Chadee DD, Severson DW. Influence of urban landscapes on population dynamics in a short-distance migrant mosquito: evidence for the dengue vector Aedes aegypti. PLoS Negl Trop Dis 2010; 4:e634. [PMID: 20300516 PMCID: PMC2838782 DOI: 10.1371/journal.pntd.0000634] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Accepted: 01/28/2010] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Dengue viruses are endemic across most tropical and subtropical regions. Because no proven vaccines are available, dengue prevention is primarily accomplished through controlling the mosquito vector Aedes aegypti. While dispersal distance is generally believed to be approximately 100 m, patterns of dispersion may vary in urban areas due to landscape features acting as barriers or corridors to dispersal. Anthropogenic features ultimately affect the flow of genes affecting vector competence and insecticide resistance. Therefore, a thorough understanding of what parameters impact dispersal is essential for efficient implementation of any mosquito population suppression program. Population replacement and genetic control strategies currently under consideration are also dependent upon a thorough understanding of mosquito dispersal in urban settings. METHODOLOGY AND PRINCIPAL FINDINGS We examined the effect of a major highway on dispersal patterns over a 2 year period. A. aegypti larvae were collected on the east and west sides of Uriah Butler Highway (UBH) to examine any effect UBH may have on the observed population structure in the Charlieville neighborhood in Trinidad, West Indies. A panel of nine microsatellites, two SNPs and a 710 bp sequence of mtDNA cytochrome oxidase subunit 1 (CO1) were used for the molecular analyses of the samples. Three CO1 haplotypes were identified, one of which was only found on the east side of the road in 2006 and 2007. AMOVA using mtCO1 and nuclear markers revealed significant differentiation between the east- and west-side collections. CONCLUSION AND SIGNIFICANCE Our results indicate that anthropogenic barriers to A. aegypti dispersal exist in urban environments and should be considered when implementing control programs during dengue outbreaks and population suppression or replacement programs.
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Affiliation(s)
- Ryan R. Hemme
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Clayton L. Thomas
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Dave D. Chadee
- Department of Life Sciences, University of the West Indies, St. Augustine, Trinidad and Tobago, West Indies
| | - David W. Severson
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, United States of America
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26
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Pitaluga AN, Beteille V, Lobo AR, Ortigão-Farias JR, Dávila AMR, Souza AA, Ramalho-Ortigão JM, Traub-Cseko YM. EST sequencing of blood-fed and Leishmania-infected midgut of Lutzomyia longipalpis, the principal visceral leishmaniasis vector in the Americas. Mol Genet Genomics 2009; 282:307-17. [PMID: 19565270 DOI: 10.1007/s00438-009-0466-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 06/09/2009] [Indexed: 11/30/2022]
Abstract
Leishmaniasis is an important worldwide public health problem. Visceral leishmaniasis caused by Leishmania infantum chagasi is mainly transmitted by Lutzomyia longipalpis in the Americas. Leishmania development within the sand fly vector is mostly restricted to the midgut. Thus, a comparative analysis of blood-fed versus infected midguts may provide an invaluable insight into various aspects of sand fly immunity, physiology of blood digestion, and, more importantly, of Leishmania development. To that end, we have engaged in a study to identify expressed sequenced tags (ESTs) from L. longipalpis cDNA libraries produced from midguts dissected at different times post blood meal and also after artificial infection with L. i. chagasi. A total of 2,520 ESTs were obtained and, according to the quality of the sequencing data obtained, assembled into 378 clusters and 1,526 individual sequences or singletons totalizing 1,904 sequences. Several sequences associated with defense, apoptosis, RNAi, and digestion processes were annotated. The data presented here increases current knowledge on the New World sand fly transcriptome, contributing to the understanding of various aspects of the molecular physiology of L. longipalpis, and mechanisms underlying the relationship of this sand fly species with L. i. chagasi.
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Affiliation(s)
- André N Pitaluga
- Laboratório de Biologia Molecular de Tripanosomatídeos e Flebotomíneos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, RJ, Brazil
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28
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Mehlotra RK, Henry-Halldin CN, Zimmerman PA. Application of pharmacogenomics to malaria: a holistic approach for successful chemotherapy. Pharmacogenomics 2009; 10:435-49. [PMID: 19290792 DOI: 10.2217/14622416.10.3.435] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Drug resistance in malaria jeopardizes the most elementary objectives of malaria control--reducing suffering and eliminating mortality. An important, and so far the only known, mechanism of drug resistance appears to be polymorphisms in the malaria parasite genes. Efforts to circumvent antimalarial drug resistance now range from the use of combination therapies with existing agents to genomics-based studies directed toward discovering novel targets and agents. However, the potential contribution of host genetic/molecular factors, particularly those associated with antimalarial drug metabolism, remains largely unexplored. Our knowledge concerning the basic mechanisms involved in the pharmacokinetics of antimalarial drugs is fragmentary. In addition, the link between antimalarial drug pharmacokinetics and treatment outcomes is generally unclear. The purpose of this article is to provide general background information on antimalarial drug resistance and associated parasite genetic factors, and subsequently highlight the aforementioned unexplored and unclear areas, with a view to stimulate much needed further research.
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Affiliation(s)
- Rajeev K Mehlotra
- Center for Global Health and Diseases, Case Western Reserve University, School of Medicine, Wolstein Research Building #4204, 2103 Cornell Road, Cleveland, OH 44106-7286, USA.
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29
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Conservation and immunogenicity of the mosquito ortholog of the tick-protective antigen, subolesin. Parasitol Res 2009; 105:97-111. [PMID: 19229557 DOI: 10.1007/s00436-009-1368-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2008] [Accepted: 01/29/2009] [Indexed: 12/18/2022]
Abstract
The control of arthropod vectors of pathogens that affect human and animal health is important for the eradication of vector-borne diseases. The ortholog of the tick-protective antigen, subolesin, was identified in Aedes albopictus and found to have conserved epitopes in ticks and mosquitoes. RNA interference with the tick and mosquito double-stranded RNA in three tick species resulted in significant gene knockdown and decreased tick weight and/or survival. Feeding Anopheles atroparvus, Aedes caspius, and Culex pipiens female mosquitoes on an A. albopictus subolesin hyperimmune serum resulted in 11 +/- 5% to 29 +/- 6% survival inhibition when compared to controls fed on preimmune serum. Feeding sand flies, Phlebotomus perniciosus, on antimosquito subolesin ortholog protein antibodies inhibited female survival and the number of larvae and adults obtained after hatching by 28 +/- 22% and 16 +/- 3%, respectively, when compared to controls. Vaccination with tick and mosquito subolesin ortholog proteins significantly reduced Ixodes scapularis tick infestation and weight in a similar way. However, vaccination with the recombinant mosquito subolesin ortholog antigen did not protect against Amblyomma americanum and Rhipicephalus sanguineus tick infestations. Collectively, these preliminary results provided the first evidence that development of vaccines may be possible for control of multiple arthropod vectors using subolesin orthologs but suggested that multiple antigens may be required to produce an effective vaccine.
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30
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Teixeira MG, Costa MDCN, Barreto F, Barreto ML. Dengue: twenty-five years since reemergence in Brazil. CAD SAUDE PUBLICA 2009; 25 Suppl 1:S7-18. [DOI: 10.1590/s0102-311x2009001300002] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2008] [Accepted: 07/03/2008] [Indexed: 11/21/2022] Open
Abstract
This article revisits the epidemiology of dengue in Brazil, 25 years after its reemergence in the country, discussing the main determinants and implications for its control. The authors emphasize the clinical and epidemiological peculiarities of this viral disease in Brazil, which leads the world in both the number of cases reported and risk of occurrence of the disease. The article presents the changes occurring in the dengue epidemiological pattern in recent years, like the sudden age shift in the incidence of dengue hemorrhagic fever, and discusses possible associated factors. The article focuses specifically on the epidemic in Rio de Janeiro in 2008, this episode's impact on the international community, and the fear that the disease could spread to Europe. The authors conclude that the current situation emphasizes the need for the international scientific community to renew its efforts to generate knowledge allowing improvement and progress in the development of new tools and strategies for dengue prevention.
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31
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Gusmão DS, Santos AV, Marini DC, Russo EDS, Peixoto AMD, Bacci Júnior M, Berbert-Molina MA, Lemos FJA. First isolation of microorganisms from the gut diverticulum of Aedes aegypti (Diptera: Culicidae): new perspectives for an insect-bacteria association. Mem Inst Oswaldo Cruz 2008; 102:919-24. [PMID: 18209929 DOI: 10.1590/s0074-02762007000800005] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2007] [Accepted: 11/23/2007] [Indexed: 11/22/2022] Open
Abstract
We show for the first time that the ventral diverticulum of the mosquito gut (impermeable sugar storage organ) harbors microorganisms. The gut diverticulum from newly emerged and non-fed Aedes aegypti was dissected under aseptic conditions, homogenized and plated on BHI medium. Microbial isolates were identified by sequencing of 16S rDNA for bacteria and 28S rDNA for yeast. A direct DNA extraction from Ae. aegypti gut diverticulum was also performed. The bacterial isolates were: Bacillus sp., Bacillus subtilis and Serratia sp. The latter was the predominant bacteria found in our isolations. The yeast species identified was Pichia caribbica.
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Affiliation(s)
- Desiely Silva Gusmão
- Laboratório de Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, 28013-602 Campos dos Goytacazes, RJ, Brasil
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