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Zhang X, Zhang S, Kuang J, Sellens KA, Morejon B, Saab SA, Li M, Metto EC, An C, Culbertson CT, Osta MA, Scoglio C, Michel K. CLIPB4 Is a Central Node in the Protease Network that Regulates Humoral Immunity in Anopheles gambiae Mosquitoes. J Innate Immun 2023; 15:680-696. [PMID: 37703846 PMCID: PMC10603620 DOI: 10.1159/000533898] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 08/29/2023] [Indexed: 09/15/2023] Open
Abstract
Insect humoral immune responses are regulated in part by protease cascades, whose components circulate as zymogens in the hemolymph. In mosquitoes, these cascades consist of clip-domain serine proteases (cSPs) and/or their non-catalytic homologs, which form a complex network, whose molecular make-up is not fully understood. Using a systems biology approach, based on a co-expression network of gene family members that function in melanization and co-immunoprecipitation using the serine protease inhibitor (SRPN)2, a key negative regulator of the melanization response in mosquitoes, we identify the cSP CLIPB4 from the African malaria mosquito Anopheles gambiae as a central node in this protease network. CLIPB4 is tightly co-expressed with SRPN2 and forms protein complexes with SRPN2 in the hemolymph of immune-challenged female mosquitoes. Genetic and biochemical approaches validate our network analysis and show that CLIPB4 is required for melanization and antibacterial immunity, acting as a prophenoloxidase (proPO)-activating protease, which is inhibited by SRPN2. In addition, we provide novel insight into the structural organization of the cSP network in An. gambiae, by demonstrating that CLIPB4 is able to activate proCLIPB8, a cSP upstream of the proPO-activating protease CLIPB9. These data provide the first evidence that, in mosquitoes, cSPs provide branching points in immune protease networks and deliver positive reinforcement in proPO activation cascades.
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Affiliation(s)
- Xiufeng Zhang
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Shasha Zhang
- Division of Biology, Kansas State University, Manhattan, KS, USA
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Junyao Kuang
- Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS, USA
| | | | - Bianca Morejon
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Sally A. Saab
- Department of Biology, American University of Beirut, Beirut, Lebanon
| | - Miao Li
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Eve C. Metto
- Department of Chemistry, Kansas State University, Manhattan, KS, USA
| | - Chunju An
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
| | | | - Mike A. Osta
- Department of Biology, American University of Beirut, Beirut, Lebanon
| | - Caterina Scoglio
- Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS, USA
| | - Kristin Michel
- Division of Biology, Kansas State University, Manhattan, KS, USA
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2
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Wang HC, Wang QH, Bhowmick B, Li YX, Han Q. Functional characterization of two clip domain serine proteases in innate immune responses of Aedes aegypti. Parasit Vectors 2021; 14:584. [PMID: 34819136 PMCID: PMC8611957 DOI: 10.1186/s13071-021-05091-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 11/08/2021] [Indexed: 11/12/2022] Open
Abstract
Background Clip domain serine proteases (CLIPs), a very diverse group of proteolytic enzymes, play a crucial role in the innate immunity of insects. Innate immune responses are the first line of defense in mosquitoes against the invasion of pathogenic microorganisms. The Toll pathway, immunodeficiency (IMD) pathway and melanization are the main processes of innate immunity in Aedes aegypti. CLIPS are classified into five subfamilies—CLIPA, CLIPB, CLIPC, CLIPD, and CLIPE—based on their sequence specificity and phylogenetic relationships. We report the functional characterization of the genes that code for two CLIPs in Ae. aegypti (Ae): Ae-CLIPB15 and Ae-CLIPB22. Methods Clustal Omega was used for multiple amino acid sequence alignment of Ae-CLIPB15 and Ae-CLIPB22 with different CLIP genes from other insect species. The spatiotemporal expression profiles of Ae-CLIPB15 and Ae-CLIPB22 were examined. We determined whether Ae-CLIPB15 and Ae-CLIPB22 respond to microbial challenge and tissue injury. RNA interference (RNAi) was used to explore the function of Ae-CLIPB15 and Ae-CLIPB22 in the defense of Ae. aegypti against bacterial and fungal infections. The expression levels of nuclear factor kappa B (NF-κB) transcription factors REL1 and REL2 in the Toll pathway and IMD pathway after bacterial infection were investigated. Finally, the change in phenoloxidase (PO) activity in Ae-CLIPB15 and Ae-CLIPB22 knockdown adults was investigated. Results We performed spatiotemporal gene expression profiling of Ae-CLIPB15 and Ae-CLIPB22 genes in Ae. aegypti using quantitative real-time polymerase chain reaction. These genes were expressed in different stages and tissues. The messenger RNA (mRNA) levels for both genes were also up-regulated by Gram-negative bacteria Escherichia coli, Gram-positive bacteria Staphylococcus aureus and fungal Beauveria bassiana infections, as well as in the tissue injury experiments. RNAi-mediated knockdown of Ae-CLIPB15 led to a significant decrease of PO activity in the hemolymph of Ae. aegypti, while other RNAi experiments revealed that both Ae-CLIPB15 and Ae-CLIPB22 were involved in immune defense against bacterial and fungal infections. The mRNA expression of NF-κB transcription factors REL1 and REL2 in the Toll pathway and IMD pathway differed between Ae-CLIPB15 and Ae-CLIPB22 knockdown mosquitoes infected with bacteria and wild type mosquitoes infected with bacteria. Conclusions Our findings suggest that Ae-CLIPB15 and Ae-CLIPB22 play a critical role in mosquito innate immunity, and that they are involved in immune responses to injury and infection. Their regulation of transcription factors and PO activity indicates that they also play a specific role in the regulation of innate immunity. Graphical Abstract ![]()
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Affiliation(s)
- Hao-Cheng Wang
- Laboratory of Tropical Veterinary Medicine and Vector Biology, School of Life Sciences, Hainan University, Haikou, Hainan, 570228, People's Republic of China.,One Health Institute, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Qiu-Hui Wang
- Laboratory of Tropical Veterinary Medicine and Vector Biology, School of Life Sciences, Hainan University, Haikou, Hainan, 570228, People's Republic of China.,One Health Institute, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Biswajit Bhowmick
- Laboratory of Tropical Veterinary Medicine and Vector Biology, School of Life Sciences, Hainan University, Haikou, Hainan, 570228, People's Republic of China.,One Health Institute, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Yi-Xun Li
- Laboratory of Tropical Veterinary Medicine and Vector Biology, School of Life Sciences, Hainan University, Haikou, Hainan, 570228, People's Republic of China.,One Health Institute, Hainan University, Haikou, Hainan, 570228, People's Republic of China
| | - Qian Han
- Laboratory of Tropical Veterinary Medicine and Vector Biology, School of Life Sciences, Hainan University, Haikou, Hainan, 570228, People's Republic of China. .,One Health Institute, Hainan University, Haikou, Hainan, 570228, People's Republic of China.
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3
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Kwon H, Mohammed M, Franzén O, Ankarklev J, Smith RC. Single-cell analysis of mosquito hemocytes identifies signatures of immune cell subtypes and cell differentiation. eLife 2021; 10:66192. [PMID: 34318744 PMCID: PMC8376254 DOI: 10.7554/elife.66192] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Accepted: 07/27/2021] [Indexed: 12/16/2022] Open
Abstract
Mosquito immune cells, known as hemocytes, are integral to cellular and humoral responses that limit pathogen survival and mediate immune priming. However, without reliable cell markers and genetic tools, studies of mosquito immune cells have been limited to morphological observations, leaving several aspects of their biology uncharacterized. Here, we use single-cell RNA sequencing (scRNA-seq) to characterize mosquito immune cells, demonstrating an increased complexity to previously defined prohemocyte, oenocytoid, and granulocyte subtypes. Through functional assays relying on phagocytosis, phagocyte depletion, and RNA-FISH experiments, we define markers to accurately distinguish immune cell subtypes and provide evidence for immune cell maturation and differentiation. In addition, gene-silencing experiments demonstrate the importance of lozenge in defining the mosquito oenocytoid cell fate. Together, our scRNA-seq analysis provides an important foundation for future studies of mosquito immune cell biology and a valuable resource for comparative invertebrate immunology.
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Affiliation(s)
- Hyeogsun Kwon
- Department of Entomology, Iowa State University, Ames, United States
| | - Mubasher Mohammed
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Oscar Franzén
- Integrated Cardio Metabolic Centre, Department of Medicine, Karolinska Institutet, Novum, Huddinge, Sweden
| | - Johan Ankarklev
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden.,Microbial Single Cell Genomics facility, SciLifeLab, Biomedical Center (BMC) Uppsala University, Uppsala, Sweden
| | - Ryan C Smith
- Department of Entomology, Iowa State University, Ames, United States
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4
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Dietary and Plasmodium challenge effects on the cuticular hydrocarbon profile of Anopheles albimanus. Sci Rep 2021; 11:11258. [PMID: 34045618 PMCID: PMC8159922 DOI: 10.1038/s41598-021-90673-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 05/13/2021] [Indexed: 02/04/2023] Open
Abstract
The cuticular hydrocarbon (CHC) profile reflects the insects' physiological states. These include age, sex, reproductive stage, and gravidity. Environmental factors such as diet, relative humidity or exposure to insecticides also affect the CHC composition in mosquitoes. In this work, the CHC profile was analyzed in two Anopheles albimanus phenotypes with different degrees of susceptibility to Plasmodium, the susceptible-White and resistant-Brown phenotypes, in response to the two dietary regimes of mosquitoes: a carbon-rich diet (sugar) and a protein-rich diet (blood) alone or containing Plasmodium ookinetes. The CHCs were analyzed by gas chromatography coupled to mass spectrometry or flame ionization detection, identifying 19 CHCs with chain lengths ranging from 20 to 37 carbons. Qualitative and quantitative changes in CHCs composition were dependent on diet, a parasite challenge, and, to a lesser extent, the phenotype. Blood-feeding caused up to a 40% reduction in the total CHC content compared to sugar-feeding. If blood contained ookinetes, further changes in the CHC profile were observed depending on the Plasmodium susceptibility of the phenotypes. Higher infection prevalence caused greater changes in the CHC profile. These dietary and infection-associated modifications in the CHCs could have multiple effects on mosquito fitness, impacts on disease transmission, and tolerance to insecticides.
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5
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Carvajal-Lago L, Ruiz-López MJ, Figuerola J, Martínez-de la Puente J. Implications of diet on mosquito life history traits and pathogen transmission. ENVIRONMENTAL RESEARCH 2021; 195:110893. [PMID: 33607093 DOI: 10.1016/j.envres.2021.110893] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 06/12/2023]
Abstract
The environment, directly and indirectly, affects many mosquito traits in both the larval and adult stages. The availability of food resources is one of the key factors influencing these traits, although its role in mosquito fitness and pathogen transmission remains unclear. Larvae nutritional status determines their survivorship and growth, having also an impact on adult characteristics like longevity, body size, flight capacity or vector competence. During the adult stage, mosquito diet affects their survival rate, fecundity and host-seeking behaviour. It also affects mosquito susceptibility to infection, which may determine the vectorial capacity of mosquito populations. The aim of this review is to critically revise the current knowledge on the effects that both larval and adult quantity and quality of the diet have on mosquito life history traits, identifying the critical knowledge gaps and proposing future research lines. The quantity and quality of food available through their lifetime greatly determine adult body size, longevity or biting frequency, therefore affecting their competence for pathogen transmission. In addition, natural sugar sources for adult mosquitoes, i.e., specific plants providing high metabolic energy, might affect their host-seeking and vertebrate biting behaviour. However, most of the studies are carried out under laboratory conditions, highlighting the need for studies of feeding behaviour of mosquitoes under field conditions. This kind of studies will increase our knowledge of the impact of diets on pathogen transmission, helping to develop successful control plans for vector-borne diseases.
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Affiliation(s)
- Laura Carvajal-Lago
- Departamento de Ecología de Humedales, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, CSIC, Spain
| | - María José Ruiz-López
- Departamento de Ecología de Humedales, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, CSIC, Spain
| | - Jordi Figuerola
- Departamento de Ecología de Humedales, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, CSIC, Spain; CIBER de Epidemiología y Salud Pública (CIBERESP), Spain.
| | - Josué Martínez-de la Puente
- Departamento de Ecología de Humedales, Estación Biológica de Doñana, Consejo Superior de Investigaciones Científicas, CSIC, Spain; Departamento de Parasitología, Facultad de Farmacia, Campus Universitario de Cartuja, Universidad de Granada, 18071 Granada, Spain; CIBER de Epidemiología y Salud Pública (CIBERESP), Spain
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6
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Additional Feeding Reveals Differences in Immune Recognition and Growth of Plasmodium Parasites in the Mosquito Host. mSphere 2021; 6:6/2/e00136-21. [PMID: 33789941 PMCID: PMC8546690 DOI: 10.1128/msphere.00136-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Mosquitoes may feed multiple times during their life span in addition to those times needed to acquire and transmit malaria. To determine the impact of subsequent blood feeding on parasite development in Anopheles gambiae, we examined Plasmodium parasite infection with or without an additional noninfected blood meal. We found that an additional blood meal significantly reduced Plasmodium berghei immature oocyst numbers, yet had no effect on the human parasite Plasmodium falciparum. These observations were reproduced when mosquitoes were fed an artificial protein meal, suggesting that parasite losses are independent of blood ingestion. We found that feeding with either a blood or protein meal compromises midgut basal lamina integrity as a result of the physical distention of the midgut, enabling the recognition and lysis of immature P. berghei oocysts by mosquito complement. Moreover, we demonstrate that additional feeding promotes P. falciparum oocyst growth, suggesting that human malaria parasites exploit host resources provided with blood feeding to accelerate their growth. This is in contrast to experiments with P. berghei, where the size of surviving oocysts is independent of an additional blood meal. Together, these data demonstrate distinct differences in Plasmodium species in evading immune detection and utilizing host resources at the oocyst stage, representing an additional, yet unexplored component of vectorial capacity that has important implications for the transmission of malaria. IMPORTANCE Mosquitoes must blood feed multiple times to acquire and transmit malaria. However, the impact of an additional mosquito blood meal following malaria parasite infection has not been closely examined. Here, we demonstrate that additional feeding affects mosquito vector competence; namely, additional feeding significantly limits Plasmodium berghei infection, yet has no effect on infection of the human parasite P. falciparum. Our experiments support that these killing responses are mediated by the physical distension of the midgut and by temporary damage to the midgut basal lamina that exposes immature P. berghei oocysts to mosquito complement, while human malaria parasites are able to evade these killing mechanisms. In addition, we provide evidence that additional feeding promotes P. falciparum oocyst growth. This is in contrast to P. berghei, where oocyst size is independent of an additional blood meal. This suggests that human malaria parasites are able to exploit host resources provided by an additional feeding to accelerate their growth. In summary, our data highlight distinct differences in malaria parasite species in evading immune recognition and adapting to mosquito blood feeding. These observations have important, yet previously unexplored, implications for the impact of multiple blood meals on the transmission of malaria.
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7
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Alves E Silva TL, Radtke A, Balaban A, Pascini TV, Pala ZR, Roth A, Alvarenga PH, Jeong YJ, Olivas J, Ghosh AK, Bui H, Pybus BS, Sinnis P, Jacobs-Lorena M, Vega-Rodríguez J. The fibrinolytic system enables the onset of Plasmodium infection in the mosquito vector and the mammalian host. SCIENCE ADVANCES 2021; 7:7/6/eabe3362. [PMID: 33547079 PMCID: PMC7864569 DOI: 10.1126/sciadv.abe3362] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 12/21/2020] [Indexed: 05/06/2023]
Abstract
Plasmodium parasites must migrate across proteinaceous matrices to infect the mosquito and vertebrate hosts. Plasmin, a mammalian serine protease, degrades extracellular matrix proteins allowing cell migration through tissues. We report that Plasmodium gametes recruit human plasminogen to their surface where it is processed into plasmin by corecruited plasminogen activators. Inhibition of plasminogen activation arrests parasite development early during sexual reproduction, before ookinete formation. We show that increased fibrinogen and fibrin in the blood bolus, which are natural substrates of plasmin, inversely correlate with parasite infectivity of the mosquito. Furthermore, we show that sporozoites, the parasite form transmitted by the mosquito to humans, also bind plasminogen and plasminogen activators on their surface, where plasminogen is activated into plasmin. Surface-bound plasmin promotes sporozoite transmission by facilitating parasite migration across the extracellular matrices of the dermis and of the liver. The fibrinolytic system is a potential target to hamper Plasmodium transmission.
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Affiliation(s)
- Thiago Luiz Alves E Silva
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
- Laboratório de Bioquímica de Resposta ao Estresse, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Andrea Radtke
- Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20814, USA
| | - Amanda Balaban
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Tales Vicari Pascini
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Zarna Rajeshkumar Pala
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Alison Roth
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Patricia H Alvarenga
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
- Laboratório de Bioquímica de Resposta ao Estresse, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Yeong Je Jeong
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Janet Olivas
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Anil K Ghosh
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Hanhvy Bui
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Brandon S Pybus
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Photini Sinnis
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Marcelo Jacobs-Lorena
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA.
| | - Joel Vega-Rodríguez
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology and Johns Hopkins Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA.
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8
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Abstract
Factors such as the particular combination of parasite-mosquito species, their co-evolutionary history and the host's parasite load greatly affect parasite transmission. However, the importance of these factors in the epidemiology of mosquito-borne parasites, such as avian malaria parasites, is largely unknown. Here, we assessed the competence of two mosquito species [Culex pipiens and Aedes (Ochlerotatus) caspius], for the transmission of four avian Plasmodium lineages (Plasmodium relictum SGS1 and GRW11 and Plasmodium cathemerium-related lineages COLL1 and PADOM01) naturally infecting wild house sparrows. We assessed the effects of parasite identity and parasite load on Plasmodium transmission risk through its effects on the transmission rate and mosquito survival. We found that Cx. pipiens was able to transmit the four Plasmodium lineages, while Ae. caspius was unable to transmit any of them. However, Cx. pipiens mosquitoes fed on birds infected by P. relictum showed a lower survival and transmission rate than those fed on birds infected by parasites related to P. cathemerium. Non-significant associations were found with the host-parasite load. Our results confirm the existence of inter- and intra-specific differences in the ability of Plasmodium lineages to develop in mosquito species and their effects on the survival of mosquitoes that result in important differences in the transmission risk of the different avian malaria parasite lineages studied.
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9
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Chemical depletion of phagocytic immune cells in Anopheles gambiae reveals dual roles of mosquito hemocytes in anti- Plasmodium immunity. Proc Natl Acad Sci U S A 2019; 116:14119-14128. [PMID: 31235594 DOI: 10.1073/pnas.1900147116] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Mosquito immunity is composed of both cellular and humoral factors that provide protection from invading pathogens. Immune cells known as hemocytes, have been intricately associated with phagocytosis and innate immune signaling. However, the lack of genetic tools has limited hemocyte study despite their importance in mosquito anti-Plasmodium immunity. To address these limitations, we employ the use of a chemical-based treatment to deplete phagocytic immune cells in Anopheles gambiae, demonstrating the role of phagocytes in complement recognition and prophenoloxidase production that limit the ookinete and oocyst stages of malaria parasite development, respectively. Through these experiments, we also define specific subtypes of phagocytic immune cells in An. gambiae, providing insights beyond the morphological characteristics that traditionally define mosquito hemocyte populations. Together, this study represents a significant advancement in our understanding of the roles of mosquito phagocytes in mosquito vector competence and demonstrates the utility of clodronate liposomes as an important tool in the study of invertebrate immunity.
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10
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Gutiérrez-López R, Martínez-de la Puente J, Gangoso L, Yan J, Soriguer R, Figuerola J. Experimental reduction of host Plasmodium infection load affects mosquito survival. Sci Rep 2019; 9:8782. [PMID: 31217438 PMCID: PMC6584735 DOI: 10.1038/s41598-019-45143-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 05/17/2019] [Indexed: 12/20/2022] Open
Abstract
Plasmodium transmission success depends upon the trade-off between the use of host resources to favour parasite reproduction and the negative effects on host health, which can be mediated by infection intensity. Despite its potential influence on parasite dynamics, the effects of infection intensity on both, birds and vectors, and on Plasmodium transmission success are still poorly understood. Here, we experimentally reduced the Plasmodium load in naturally infected wild house sparrows with the antimalarial primaquine to assess the effects of intensity of infection in the vertebrate hosts on Plasmodium transmission to and by mosquitoes. We monitored the survival of Culex pipiens mosquitoes throughout the development of the parasite and the infection status of the mosquitoes by analysing the head-thorax and saliva at 13 days post-exposure to birds. The proportion of mosquitoes infected by Plasmodium and the presence of Plasmodium in saliva were not associated with the medication treatment of birds. However, the experimental treatment affected vector survival with mosquitoes fed on medicated birds showing a higher survival rate than those fed on control individuals. These results provide strong experimental evidence of the impact of parasite load of vertebrate hosts on the survival probability of malaria vectors.
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Affiliation(s)
- Rafael Gutiérrez-López
- Department of Wetland Ecology, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio 26, E-41092, Seville, Spain.
| | - Josué Martínez-de la Puente
- Department of Wetland Ecology, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio 26, E-41092, Seville, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Seville, Spain
| | - Laura Gangoso
- Department of Wetland Ecology, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio 26, E-41092, Seville, Spain.,Theoretical and Computational Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park, 904 1098 XH, Amsterdam, The Netherlands
| | - Jiayue Yan
- Department of Wetland Ecology, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio 26, E-41092, Seville, Spain.,Illinois Natural History Survey, University of Illinois, 1816 S Oak St., Champaign 61820, Illinois, USA
| | - Ramón Soriguer
- Department of Ethology & Biodiversity Conservation, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio 26, E-41092, Sevilla, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Seville, Spain
| | - Jordi Figuerola
- Department of Wetland Ecology, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio 26, E-41092, Seville, Spain.,CIBER Epidemiología y Salud Pública (CIBERESP), Seville, Spain
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11
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Bartholomay LC, Michel K. Mosquito Immunobiology: The Intersection of Vector Health and Vector Competence. ANNUAL REVIEW OF ENTOMOLOGY 2018; 63:145-167. [PMID: 29324042 DOI: 10.1146/annurev-ento-010715-023530] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
As holometabolous insects that occupy distinct aquatic and terrestrial environments in larval and adult stages and utilize hematophagy for nutrient acquisition, mosquitoes are subjected to a wide variety of symbiotic interactions. Indeed, mosquitoes play host to endosymbiotic, entomopathogenic, and mosquito-borne organisms, including protozoa, viruses, bacteria, fungi, fungal-like organisms, and metazoans, all of which trigger and shape innate infection-response capacity. Depending on the infection or interaction, the mosquito may employ, for example, cellular and humoral immune effectors for septic infections in the hemocoel, humoral infection responses in the midgut lumen, and RNA interference and programmed cell death for intracellular pathogens. These responses often function in concert, regardless of the infection type, and provide a robust front to combat infection. Mosquito-borne pathogens and entomopathogens overcome these immune responses, employing avoidance or suppression strategies. Burgeoning methodologies are capitalizing on this concerted deployment of immune responses to control mosquito-borne disease.
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Affiliation(s)
- Lyric C Bartholomay
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Wisconsin 53706;
| | - Kristin Michel
- Division of Biology, Kansas State University, Manhattan, Kansas 66506;
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12
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Abstract
Malaria parasite ookinetes must traverse the vector mosquito midgut epithelium to transform into sporozoite-producing oocysts. The Anopheles innate immune system is a key regulator of this process, thereby determining vector competence and disease transmission. The role of Anopheles innate immunity factors as agonists or antagonists of malaria parasite infection has been previously determined using specific single Anopheles-Plasmodium species combinations. Here we show that the two C-type lectins CTL4 and CTLMA2 exert differential agonistic and antagonistic regulation of parasite killing in African and South American Anopheles species. The C-type lectins regulate both parasite melanization and lysis through independent mechanisms, and their implication in parasite melanization is dependent on infection intensity rather than mosquito-parasite species combination. We show that the leucine-rich repeat protein LRIM1 acts as an antagonist on the development of Plasmodium ookinetes and as a regulator of oocyst size and sporozoite production in the South American mosquito Anopheles albimanus. Our findings explain the rare observation of human Plasmodium falciparum melanization and define a key factor mediating the poor vector competence of Anopheles albimanus for Plasmodium berghei and Plasmodium falciparum. Malaria, one of the world’s deadliest diseases, is caused by Plasmodium parasites that are vectored to humans by the bite of Anopheles mosquitoes. The mosquito’s innate immune system is actively engaged in suppressing Plasmodium infection. Studies on mosquito immunity revealed multiple factors that act as either facilitators or inhibitors of Plasmodium infection, but these findings were mostly based on single Anopheles-Plasmodium species combinations, not taking into account the diversity of mosquito and parasite species. We show that the functions of CTL4 and CTLMA2 have diverged in different vector species and can be both agonistic and antagonistic for Plasmodium infection. Their protection against parasite melanization in Anopheles gambiae is dependent on infection intensity, rather than the mosquito-parasite combination. Importantly, we describe for the first time how LRIM1 plays an essential role in Plasmodium infection of Anopheles albimanus, suggesting it is a key regulator of the poor vector competence of this species.
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13
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Kwon H, Arends BR, Smith RC. Late-phase immune responses limiting oocyst survival are independent of TEP1 function yet display strain specific differences in Anopheles gambiae. Parasit Vectors 2017; 10:369. [PMID: 28764765 PMCID: PMC5540282 DOI: 10.1186/s13071-017-2308-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 07/25/2017] [Indexed: 11/18/2022] Open
Abstract
Background There is emerging evidence that mosquito anti-Plasmodium immunity is multimodal with distinct mechanisms for killing malaria parasites at either the ookinete or oocyst stages. Early-phase responses targeting the ookinete require complement-like components circulating in the mosquito hemolymph that result in TEP1-mediated lysis or melanization. Additional responses mediated by the LL3 and STAT pathways limit oocyst survival through unknown mechanisms that require mosquito hemocyte function. While previous experiments argue that these mechanisms of parasite killing are independent, the transient nature of gene-silencing has rendered these experiments inconclusive. To address this issue, we outline experiments using a TALEN-derived TEP1 mutant line to examine the role of TEP1 in the Anopheles gambiae late-phase immune response. Results Despite higher early oocyst numbers in the TEP1 mutant line, no differences in oocyst survival were observed when compared to control mosquitoes, suggesting that TEP1 function is independent of the late-phase immune response. To further validate this phenotype in the TEP1 mutant, oocyst survival was evaluated in the TEP1 mutant background by silencing either LL3 or STAT-A. Surprisingly, only STAT-A silenced mosquitoes were able to reconstitute the late-phase immune phenotype increasing oocyst survival in the TEP1 mutant line. Additional experiments highlight significant differences in LL3 expression in the M/S hybrid genetic background of the TEP1 mutant line compared to that of the Keele strain (M form) of An. gambiae, and demonstrate that LL3 is not required for granulocyte differentiation in the M/S hybrid G3 genetic background in response to malaria parasite infection. Conclusions Through the combination of genetic experiments utilizing genetic mutants and reverse genetic approaches, new information has emerged regarding the mechanisms of mosquito late-phase immunity. When combined with previously published experiments, the body of evidence argues that Plasmodium oocyst survival is TEP1 independent, thus establishing that the mechanisms of early- and late-phase immunity are distinct. Moreover, we identify that the known components that mediate oocyst survival are susceptible to strain-specific differences depending on their genetic background and provide further evidence that the signals that promote hemocyte differentiation are required to limit oocyst survival. Together, this study provides new insights into the mechanisms of oocyst killing and the importance of genetics in shaping mosquito vector competence. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-2308-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hyeogsun Kwon
- Department of Entomology, Iowa State University, Ames, Iowa, 50011, USA
| | - Benjamin R Arends
- Department of Entomology, Iowa State University, Ames, Iowa, 50011, USA
| | - Ryan C Smith
- Department of Entomology, Iowa State University, Ames, Iowa, 50011, USA.
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14
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League GP, Estévez-Lao TY, Yan Y, Garcia-Lopez VA, Hillyer JF. Anopheles gambiae larvae mount stronger immune responses against bacterial infection than adults: evidence of adaptive decoupling in mosquitoes. Parasit Vectors 2017; 10:367. [PMID: 28764812 PMCID: PMC5539753 DOI: 10.1186/s13071-017-2302-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 07/20/2017] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND The immune system of adult mosquitoes has received significant attention because of the ability of females to vector disease-causing pathogens while ingesting blood meals. However, few studies have focused on the immune system of larvae, which, we hypothesize, is highly robust due to the high density and diversity of microorganisms that larvae encounter in their aquatic environments and the strong selection pressures at work in the larval stage to ensure survival to reproductive maturity. Here, we surveyed a broad range of cellular and humoral immune parameters in larvae of the malaria mosquito, Anopheles gambiae, and compared their potency to that of newly-emerged adults and older adults. RESULTS We found that larvae kill bacteria in their hemocoel with equal or greater efficiency compared to newly-emerged adults, and that antibacterial ability declines further with adult age, indicative of senescence. This phenotype correlates with more circulating hemocytes and a differing spatial arrangement of sessile hemocytes in larvae relative to adults, as well as with the individual hemocytes of adults carrying a greater phagocytic burden. The hemolymph of larvae also possesses markedly stronger antibacterial lytic and melanization activity than the hemolymph of adults. Finally, infection induces a stronger transcriptional upregulation of immunity genes in larvae than in adults, including differences in the immunity genes that are regulated. CONCLUSIONS These results demonstrate that immunity is strongest in larvae and declines after metamorphosis and with adult age, and suggest that adaptive decoupling, or the independent evolution of larval and adult traits made possible by metamorphosis, has occurred in the mosquito lineage.
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Affiliation(s)
- Garrett P. League
- Department of Biological Sciences, Vanderbilt University, Nashville, TN USA
| | | | - Yan Yan
- Department of Biological Sciences, Vanderbilt University, Nashville, TN USA
| | | | - Julián F. Hillyer
- Department of Biological Sciences, Vanderbilt University, Nashville, TN USA
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15
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Emami SN, Lindberg BG, Hua S, Hill SR, Mozuraitis R, Lehmann P, Birgersson G, Borg-Karlson AK, Ignell R, Faye I. A key malaria metabolite modulates vector blood seeking, feeding, and susceptibility to infection. Science 2017; 355:1076-1080. [PMID: 28183997 DOI: 10.1126/science.aah4563] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 11/15/2016] [Accepted: 01/31/2017] [Indexed: 01/02/2023]
Abstract
Malaria infection renders humans more attractive to Anopheles gambiae sensu lato mosquitoes than uninfected people. The mechanisms remain unknown. We found that an isoprenoid precursor produced by Plasmodium falciparum, (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), affects A. gambiae s.l. blood meal seeking and feeding behaviors as well as susceptibility to infection. HMBPP acts indirectly by triggering human red blood cells to increase the release of CO2, aldehydes, and monoterpenes, which together enhance vector attraction and stimulate vector feeding. When offered in a blood meal, HMBPP modulates neural, antimalarial, and oogenic gene transcription without affecting mosquito survival or fecundity; in a P. falciparum-infected blood meal, sporogony is increased.
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Affiliation(s)
- S Noushin Emami
- Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University, SE 106 91 Stockholm, Sweden.,Unit of Chemical Ecology, Department of Plant Protection Biology, SLU, SE 230 53 Alnarp, Sweden
| | - Bo G Lindberg
- Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University, SE 106 91 Stockholm, Sweden
| | - Susanna Hua
- Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University, SE 106 91 Stockholm, Sweden
| | - Sharon R Hill
- Unit of Chemical Ecology, Department of Plant Protection Biology, SLU, SE 230 53 Alnarp, Sweden
| | - Raimondas Mozuraitis
- Department of Chemistry, Organic Chemistry, Royal Institute of Technology, SE 100 44 Stockholm, Sweden.,Laboratory of Chemical and Behavioral Ecology, Institute of Ecology, Nature Research Centre, LT-08412 Vilnius, Lithuania
| | - Philipp Lehmann
- Department of Zoology, Stockholm University, SE 106 91 Stockholm, Sweden
| | - Göran Birgersson
- Unit of Chemical Ecology, Department of Plant Protection Biology, SLU, SE 230 53 Alnarp, Sweden
| | - Anna-Karin Borg-Karlson
- Department of Chemistry, Organic Chemistry, Royal Institute of Technology, SE 100 44 Stockholm, Sweden
| | - Rickard Ignell
- Unit of Chemical Ecology, Department of Plant Protection Biology, SLU, SE 230 53 Alnarp, Sweden
| | - Ingrid Faye
- Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University, SE 106 91 Stockholm, Sweden.
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16
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Emami SN, Ranford-Cartwright LC, Ferguson HM. The transmission potential of malaria-infected mosquitoes (An.gambiae-Keele, An.arabiensis-Ifakara) is altered by the vertebrate blood type they consume during parasite development. Sci Rep 2017; 7:40520. [PMID: 28094293 PMCID: PMC5240107 DOI: 10.1038/srep40520] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 12/07/2016] [Indexed: 02/04/2023] Open
Abstract
The efficiency of malaria parasite development within mosquito vectors (sporogony) is a critical determinant of transmission. Sporogony is thought to be controlled by environmental conditions and mosquito/parasite genetic factors, with minimal contribution from mosquito behaviour during the period of parasite development. We tested this assumption by investigating whether successful sporogony of Plasmodium falciparum parasites through to human-infectious transmission stages is influenced by the host species upon which infected mosquitoes feed. Studies were conducted on two major African vector species that generally are found to differ in their innate host preferences: Anopheles arabiensis and An. gambiae sensu stricto. We show that the proportion of vectors developing transmissible infections (sporozoites) was influenced by the source of host blood consumed during sporogony. The direction of this effect was associated with the innate host preference of vectors: higher sporozoite prevalences were generated in the usually human-specialist An. gambiae s.s. feeding on human compared to cow blood, whereas the more zoophilic An. arabiensis had significantly higher prevalences after feeding on cow blood. The potential epidemiological implications of these results are discussed.
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Affiliation(s)
- S Noushin Emami
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary &Life Sciences, University of Glasgow, Glasgow, Scotland, UK.,Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary &Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Lisa C Ranford-Cartwright
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary &Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Heather M Ferguson
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary &Life Sciences, University of Glasgow, Glasgow, Scotland, UK
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17
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Ranford-Cartwright LC, McGeechan S, Inch D, Smart G, Richterová L, Mwangi JM. Characterisation of Species and Diversity of Anopheles gambiae Keele Colony. PLoS One 2016; 11:e0168999. [PMID: 28033418 PMCID: PMC5199079 DOI: 10.1371/journal.pone.0168999] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/09/2016] [Indexed: 11/18/2022] Open
Abstract
Anopheles gambiae sensu stricto was recently reclassified as two species, An. coluzzii and An. gambiae s.s., in wild-caught mosquitoes, on the basis of the molecular form, denoted M or S, of a marker on the X chromosome. The An. gambiae Keele line is an outbred laboratory colony strain that was developed around 12 years ago by crosses between mosquitoes from 4 existing An. gambiae colonies. Laboratory colonies of mosquitoes often have limited genetic diversity because of small starting populations (founder effect) and subsequent fluctuations in colony size. Here we describe the characterisation of the chromosomal form(s) present in the Keele line, and investigate the diversity present in the colony using microsatellite markers on chromosome 3. We also characterise the large 2La inversion on chromosome 2. The results indicate that only the M-form of the chromosome X marker is present in the Keele colony, which was unexpected given that 3 of the 4 parent colonies were probably S-form. Levels of diversity were relatively high, as indicated by a mean number of microsatellite alleles of 6.25 across 4 microsatellites, in at least 25 mosquitoes. Both karyotypes of the inversion on chromosome 2 (2La/2L+a) were found to be present at approximately equal proportions. The Keele colony has a mixed M- and S-form origin, and in common with the PEST strain, we propose continuing to denote it as an An. gambiae s.s. line.
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Affiliation(s)
- Lisa C Ranford-Cartwright
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Sion McGeechan
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Donald Inch
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Graeme Smart
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Lenka Richterová
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Jonathan M Mwangi
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
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18
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Smith RC, Barillas-Mury C. Plasmodium Oocysts: Overlooked Targets of Mosquito Immunity. Trends Parasitol 2016; 32:979-990. [PMID: 27639778 DOI: 10.1016/j.pt.2016.08.012] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/26/2016] [Accepted: 08/30/2016] [Indexed: 12/18/2022]
Abstract
Although the ability of mosquitoes to limit Plasmodium infection is well documented, many questions remain as to how malaria parasites are recognized and killed by the mosquito host. Recent evidence suggests that anti-Plasmodium immunity is multimodal, with different immune mechanisms regulating ookinete and oocyst survival. However, most experiments determine the number of mature oocysts, without considering that different immune mechanisms may target different developmental stages of the parasite. Complement-like proteins have emerged as important determinants of early immunity targeting the ookinete stage, yet the mechanisms by which the mosquito late-phase immune response limits oocyst survival are less understood. Here, we describe the known components of the mosquito immune system that limit oocyst development, and provide insight into their possible mechanisms of action.
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Affiliation(s)
- Ryan C Smith
- Department of Entomology, Iowa State University, Ames, IA, USA.
| | - Carolina Barillas-Mury
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
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19
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Smith RC, King JG, Tao D, Zeleznik OA, Brando C, Thallinger GG, Dinglasan RR. Molecular Profiling of Phagocytic Immune Cells in Anopheles gambiae Reveals Integral Roles for Hemocytes in Mosquito Innate Immunity. Mol Cell Proteomics 2016; 15:3373-3387. [PMID: 27624304 DOI: 10.1074/mcp.m116.060723] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Indexed: 11/06/2022] Open
Abstract
The innate immune response is highly conserved across all eukaryotes and has been studied in great detail in several model organisms. Hemocytes, the primary immune cell population in mosquitoes, are important components of the mosquito innate immune response, yet critical aspects of their biology have remained uncharacterized. Using a novel method of enrichment, we isolated phagocytic granulocytes and quantified their proteomes by mass spectrometry. The data demonstrate that phagocytosis, blood-feeding, and Plasmodium falciparum infection promote dramatic shifts in the proteomic profiles of An. gambiae granulocyte populations. Of interest, large numbers of immune proteins were induced in response to blood feeding alone, suggesting that granulocytes have an integral role in priming the mosquito immune system for pathogen challenge. In addition, we identify several granulocyte proteins with putative roles as membrane receptors, cell signaling, or immune components that when silenced, have either positive or negative effects on malaria parasite survival. Integrating existing hemocyte transcriptional profiles, we also compare differences in hemocyte transcript and protein expression to provide new insight into hemocyte gene regulation and discuss the potential that post-transcriptional regulation may be an important component of hemocyte gene expression. These data represent a significant advancement in mosquito hemocyte biology, providing the first comprehensive proteomic profiling of mosquito phagocytic granulocytes during homeostasis blood-feeding, and pathogen challenge. Together, these findings extend current knowledge to further illustrate the importance of hemocytes in shaping mosquito innate immunity and their principal role in defining malaria parasite survival in the mosquito host.
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Affiliation(s)
- Ryan C Smith
- From the ‡W. Harry Feinstone Department of Molecular Microbiology and Immunology and the Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland 21205.,**Department of Entomology, Iowa State University, Ames, Iowa 50011
| | - Jonas G King
- From the ‡W. Harry Feinstone Department of Molecular Microbiology and Immunology and the Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland 21205.,‡‡Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Starkville, Mississippi 39762
| | - Dingyin Tao
- From the ‡W. Harry Feinstone Department of Molecular Microbiology and Immunology and the Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland 21205.,§§Division of Pre-clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850
| | - Oana A Zeleznik
- §Bioinformatics, Institute for Knowledge Discovery, Graz University of Technology, 8010 Graz, Austria.,¶Core Facility Bioinformatics, Austrian Centre of Industrial Biotechnology, 8010 Graz, Austria.,‖BioTechMed OMICS Center Graz, 8010 Graz, Austria
| | - Clara Brando
- From the ‡W. Harry Feinstone Department of Molecular Microbiology and Immunology and the Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland 21205
| | - Gerhard G Thallinger
- §Bioinformatics, Institute for Knowledge Discovery, Graz University of Technology, 8010 Graz, Austria.,¶Core Facility Bioinformatics, Austrian Centre of Industrial Biotechnology, 8010 Graz, Austria.,‖BioTechMed OMICS Center Graz, 8010 Graz, Austria
| | - Rhoel R Dinglasan
- From the ‡W. Harry Feinstone Department of Molecular Microbiology and Immunology and the Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland 21205; .,¶¶Emerging Pathogens Institute, Department of Infectious Diseases & Immunology, University of Florida, Gainesville, Florida 32611
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20
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Goodman CD, Siregar JE, Mollard V, Vega-Rodríguez J, Syafruddin D, Matsuoka H, Matsuzaki M, Toyama T, Sturm A, Cozijnsen A, Jacobs-Lorena M, Kita K, Marzuki S, McFadden GI. Parasites resistant to the antimalarial atovaquone fail to transmit by mosquitoes. Science 2016; 352:349-53. [PMID: 27081071 DOI: 10.1126/science.aad9279] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/10/2016] [Indexed: 12/16/2022]
Abstract
Drug resistance compromises control of malaria. Here, we show that resistance to a commonly used antimalarial medication, atovaquone, is apparently unable to spread. Atovaquone pressure selects parasites with mutations in cytochrome b, a respiratory protein with low but essential activity in the mammalian blood phase of the parasite life cycle. Resistance mutations rescue parasites from the drug but later prove lethal in the mosquito phase, where parasites require full respiration. Unable to respire efficiently, resistant parasites fail to complete mosquito development, arresting their life cycle. Because cytochrome b is encoded by the maternally inherited parasite mitochondrion, even outcrossing with wild-type strains cannot facilitate spread of resistance. Lack of transmission suggests that resistance will be unable to spread in the field, greatly enhancing the utility of atovaquone in malaria control.
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Affiliation(s)
| | - Josephine E Siregar
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia. Eijkman Institute for Molecular Biology, JI Diponegoro no. 69, Jakarta, 10430, Indonesia. Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Vanessa Mollard
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Joel Vega-Rodríguez
- Johns Hopkins University Bloomberg School of Public Health, Department of Molecular Microbiology and Immunology, Malaria Research Institute, Baltimore, MD 21205, USA
| | - Din Syafruddin
- Eijkman Institute for Molecular Biology, JI Diponegoro no. 69, Jakarta, 10430, Indonesia. Department of Parasitology, Faculty of Medicine, Hasanuddin University, Jalan Perintis Kemerdekaan Km10, Makassar 90245, Indonesia
| | - Hiroyuki Matsuoka
- Division of Medical Zoology, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
| | - Motomichi Matsuzaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tomoko Toyama
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Angelika Sturm
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Anton Cozijnsen
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Marcelo Jacobs-Lorena
- Johns Hopkins University Bloomberg School of Public Health, Department of Molecular Microbiology and Immunology, Malaria Research Institute, Baltimore, MD 21205, USA
| | - Kiyoshi Kita
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. School of Tropical Medicine and Global Health, Nagasaki University, Sakamoto, Nagasaki 852-8523, Japan
| | - Sangkot Marzuki
- Eijkman Institute for Molecular Biology, JI Diponegoro no. 69, Jakarta, 10430, Indonesia
| | - Geoffrey I McFadden
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia.
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21
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Overend G, Cabrero P, Halberg KA, Ranford-Cartwright LC, Woods DJ, Davies SA, Dow JAT. A comprehensive transcriptomic view of renal function in the malaria vector, Anopheles gambiae. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2015; 67:47-58. [PMID: 26003916 DOI: 10.1016/j.ibmb.2015.05.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 05/11/2015] [Accepted: 05/11/2015] [Indexed: 06/04/2023]
Abstract
Renal function is essential to maintain homeostasis. This is particularly significant for insects that undergo complete metamorphosis; larval mosquitoes must survive a freshwater habitat whereas adults are terrestrial, and mature females must maintain ion and fluid homeostasis after blood feeding. To investigate the physiological adaptations required for successful development to adulthood, we studied the Malpighian tubule transcriptome of Anopheles gambiae using Affymetrix arrays. We assessed transcription under several conditions; as third instar larvae, as adult males fed on sugar, as adult females fed on sugar, and adult females after a blood meal. In addition to providing the most detailed transcriptomic data to date on the Anopheles Malpighian tubules, the data provide unique information on the renal adaptations required for the switch from freshwater to terrestrial habitats, on gender differences, and on the contrast between nectar-feeding and haematophagy. We found clear differences associated with ontogenetic change in lifestyle, gender and diet, particularly in the neuropeptide receptors that control fluid secretion, and the water and ion transporters that impact volume and composition. These data were also combined with transcriptomics from the Drosophila melanogaster tubule, allowing meta-analysis of the genes which underpin tubule function across Diptera. To further investigate renal conservation across species we selected four D. melanogaster genes with orthologues highly enriched in the Anopheles tubules, and generated RNAi knockdown flies. Three of these genes proved essential, showing conservation of critical functions across 150 million years of phylogenetic separation. This extensive data-set is available as an online resource, MozTubules.org, and could potentially be mined for novel insecticide targets that can impact this critical organ in this pest species.
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Affiliation(s)
- Gayle Overend
- College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Pablo Cabrero
- College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Kenneth A Halberg
- College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK; August Krogh Centre, Department of Biology, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen, Denmark
| | | | - Debra J Woods
- College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK; Zoetis Inc., Kalamazoo, USA
| | - Shireen A Davies
- College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Julian A T Dow
- College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK.
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22
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Hemocyte differentiation mediates the mosquito late-phase immune response against Plasmodium in Anopheles gambiae. Proc Natl Acad Sci U S A 2015; 112:E3412-20. [PMID: 26080400 DOI: 10.1073/pnas.1420078112] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Plasmodium parasites must complete development in the mosquito vector for transmission to occur. The mosquito innate immune response is remarkably efficient in limiting parasite numbers. Previous work has identified a LPS-induced TNFα transcription factor (LITAF)-like transcription factor, LITAF-like 3 (LL3), which significantly influences parasite numbers. Here, we demonstrate that LL3 does not influence invasion of the mosquito midgut epithelium or ookinete-to-oocyst differentiation but mediates a late-phase immune response that decreases oocyst survival. LL3 expression in the midgut and hemocytes is activated by ookinete midgut invasion and is independent of the mosquito microbiota, suggesting that LL3 may be a component of a wound-healing response. LL3 silencing abrogates the ability of mosquito hemocytes to differentiate and respond to parasite infection, implicating hemocytes as critical modulators of the late-phase immune response.
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23
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Vega-Rodriguez J, Perez-Barreto D, Ruiz-Reyes A, Jacobs-Lorena M. Targeting molecular interactions essential for Plasmodium sexual reproduction. Cell Microbiol 2015; 17:1594-604. [PMID: 25944054 DOI: 10.1111/cmi.12458] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 04/30/2015] [Indexed: 01/15/2023]
Abstract
Malaria remains one of the most devastating infectious diseases, killing up to a million people every year. Whereas much progress has been made in understanding the life cycle of the parasite in the human host and in the mosquito vector, significant gaps of knowledge remain. Fertilization of malaria parasites, a process that takes place in the lumen of the mosquito midgut, is poorly understood and the molecular interactions (receptor-ligand) required for Plasmodium fertilization remain elusive. By use of a phage display library, we identified FG1 (Female Gamete peptide 1), a peptide that binds specifically to the surface of female Plasmodium berghei gametes. Importantly, FG1 but not a scrambled version of the peptide, strongly reduces P. berghei oocyst formation by interfering with fertilization. In addition, FG1 also inhibits P. falciparum oocyst formation suggesting that the peptide binds to a molecule on the surface of the female gamete whose structure is conserved. Identification of the molecular interactions disrupted by the FG1 peptide may lead to the development of novel malaria transmission-blocking strategies.
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Affiliation(s)
- Joel Vega-Rodriguez
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Davinia Perez-Barreto
- Departamento de Patología Animal, Producción Animal, Bromatología y Tecnología de los Alimentos Campus Universitario de Arucas - Facultad de Veterinaria, Universidad de Las Palmas de Gran Canarias, Gran Canarias, Spain
| | - Antonio Ruiz-Reyes
- Departamento de Patología Animal, Producción Animal, Bromatología y Tecnología de los Alimentos Campus Universitario de Arucas - Facultad de Veterinaria, Universidad de Las Palmas de Gran Canarias, Gran Canarias, Spain
| | - Marcelo Jacobs-Lorena
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
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Mitchell CL, Yeager RD, Johnson ZJ, D’Annunzio SE, Vogel KR, Werner T. Long-Term Resistance of Drosophila melanogaster to the Mushroom Toxin Alpha-Amanitin. PLoS One 2015; 10:e0127569. [PMID: 25978397 PMCID: PMC4433104 DOI: 10.1371/journal.pone.0127569] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 04/16/2015] [Indexed: 11/19/2022] Open
Abstract
Insect resistance to toxins exerts not only a great impact on our economy, but also on the ecology of many species. Resistance to one toxin is often associated with cross-resistance to other, sometimes unrelated, chemicals. In this study, we investigated mushroom toxin resistance in the fruit fly Drosophila melanogaster (Meigen). This fruit fly species does not feed on mushrooms in nature and may thus have evolved cross-resistance to α-amanitin, the principal toxin of deadly poisonous mushrooms, due to previous pesticide exposure. The three Asian D. melanogaster stocks used in this study, Ama-KTT, Ama-MI, and Ama-KLM, acquired α-amanitin resistance at least five decades ago in their natural habitats in Taiwan, India, and Malaysia, respectively. Here we show that all three stocks have not lost the resistance phenotype despite the absence of selective pressure over the past half century. In response to α-amanitin in the larval food, several signs of developmental retardation become apparent in a concentration-dependent manner: higher pre-adult mortality, prolonged larva-to-adult developmental time, decreased adult body size, and reduced adult longevity. In contrast, female fecundity nearly doubles in response to higher α-amanitin concentrations. Our results suggest that α-amanitin resistance has no fitness cost, which could explain why the resistance has persisted in all three stocks over the past five decades. If pesticides caused α-amanitin resistance in D. melanogaster, their use may go far beyond their intended effects and have long-lasting effects on ecosystems.
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Affiliation(s)
- Chelsea L. Mitchell
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan, United States of America
| | - Roger D. Yeager
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan, United States of America
| | - Zachary J. Johnson
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan, United States of America
| | - Stephanie E. D’Annunzio
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan, United States of America
| | - Kara R. Vogel
- Department of Experimental and Systems Pharmacology, Washington State University, Spokane, Washington, United States of America
| | - Thomas Werner
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan, United States of America
- * E-mail:
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Saddler A, Burda PC, Koella JC. Resisting infection by Plasmodium berghei increases the sensitivity of the malaria vector Anopheles gambiae to DDT. Malar J 2015; 14:134. [PMID: 25888982 PMCID: PMC4379605 DOI: 10.1186/s12936-015-0646-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 03/08/2015] [Indexed: 01/25/2023] Open
Abstract
Background The evolution of insecticide resistance threatens current malaria control methods, which rely heavily on chemical insecticides. The magnitude of the threat will be determined by the phenotypic expression of resistance in those mosquitoes that can transmit malaria. These differ from the majority of the mosquito population in two main ways; they carry sporozoites (the infectious stage of the Plasmodium parasite) and they are relatively old, as they need to survive the development period of the malaria parasite. This study examines the effects of infection by Plasmodium berghei and of mosquito age on the sensitivity to DDT in a DDT-resistant strain of Anopheles gambiae. Methods DDT-resistant Anopheles gambiae (ZANU) mosquitoes received a blood meal from either a mouse infected with Plasmodium berghei or an uninfected mouse. 10 and 19 days post blood meal the mosquitoes were exposed to 2%, 1% or 0% DDT using WHO test kits. 24 hrs after exposure, mortality and Plasmodium infection status of the mosquitoes were recorded. Results Sensitivity to DDT increased with the mosquitoes’ age and was higher in mosquitoes that had fed on Plasmodium-infected mice than in those that had not been exposed to the parasite. The latter effect was mainly due to the high sensitivity of mosquitoes that had fed on an infected mouse but were not themselves infected, while the sensitivity to DDT was only slightly higher in mosquitoes infected by Plasmodium than in those that had fed on an uninfected mouse. Conclusions The observed pattern indicates a cost of parasite-resistance. It suggests that, in addition to the detrimental effect of insecticide-resistance on control, the continued use of insecticides in a population of insecticide-resistant mosquitoes could select mosquitoes to be more susceptible to Plasmodium infection, thus further decreasing the efficacy of the control.
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Affiliation(s)
- Adam Saddler
- Division of Biology, Faculty of Life Sciences, Imperial College London, Silwood Park Campus, Ascot, Berkshire, SL5 2PZ, UK. .,Faculté des Sciences, Institut de Biologie, Université de Neuchâtel, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland. .,Department of Health Interventions, Swiss Tropical and Public Health Institute, Socinstrasse, 57, CH-4002, Basel, Switzerland. .,Ifakara Health Institute, Box 74, Bagamoyo, Tanzania. .,University of Basel, Petersplatz 1, Basel, 4003, Switzerland.
| | | | - Jacob C Koella
- Faculté des Sciences, Institut de Biologie, Université de Neuchâtel, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland.
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Biophysical analysis of anopheles gambiae leucine-rich repeat proteins APL1A1, APL1B [corrected] and APL1C and their interaction with LRIM1. PLoS One 2015; 10:e0118911. [PMID: 25775123 PMCID: PMC4361550 DOI: 10.1371/journal.pone.0118911] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 01/13/2015] [Indexed: 11/19/2022] Open
Abstract
Natural infection of Anopheles gambiae by malaria-causing Plasmodium parasites is significantly influenced by the APL1 genetic locus. The locus contains three closely related leucine-rich repeat (LRR) genes, APL1A, APL1B and APL1C. Multiple studies have reported the participation of APL1A-C in the immune response of A. gambiae to invasion by both rodent and human Plasmodium isolates. APL1C forms a heterodimer with the related LRR protein LRIM1 via a C-terminal coiled-coil domain that is also present in APL1A and APL1B. The LRIM1/APL1C heterodimer protects A. gambiae from infection by binding the complement-like protein TEP1 to form a stable and active immune complex. Here we report solution x-ray scatting data for the LRIM1/APL1C heterodimer, the oligomeric state of LRIM1/APL1 LRR domains in solution and the crystal structure of the APL1B LRR domain. The LRIM1/APL1C heterodimeric complex has a flexible and extended structure in solution. In contrast to the APL1A, APL1C and LRIM1 LRR domains, the APL1B LRR domain is a homodimer. The crystal structure of APL1B-LRR shows that the homodimer is formed by an N-terminal helix that complements for the absence of an N-terminal capping motif in APL1B, which is a unique distinction within the LRIM1/APL1 protein family. Full-length APL1A1 and APL1B form a stable complex with LRIM1. These results support a model in which APL1A1, APL1B and APL1C can all form an extended, flexible heterodimer with LRIM1, providing a repertoire of functional innate immune complexes to protect A. gambiae from a diverse array of pathogens.
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Dennison NJ, BenMarzouk-Hidalgo OJ, Dimopoulos G. MicroRNA-regulation of Anopheles gambiae immunity to Plasmodium falciparum infection and midgut microbiota. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2015; 49:170-8. [PMID: 25445902 PMCID: PMC4447300 DOI: 10.1016/j.dci.2014.10.016] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 10/24/2014] [Accepted: 10/25/2014] [Indexed: 05/03/2023]
Abstract
Invasion of the malaria vector Anopheles gambiae midgut by Plasmodium parasites triggers transcriptional changes of immune genes that mediate the antiparasitic defense. This response is largely regulated by the Toll and Immune deficiency (IMD) pathways. To determine whether A. gambiae microRNAs (miRNAs) are involved in regulating the anti-Plasmodium defense, we showed that suppression of miRNA biogenesis results in increased resistance to Plasmodium falciparum infection. In silico analysis of A. gambiae immune effector genes identified multiple transcripts with miRNA binding sites. A comparative miRNA microarray abundance analysis of P. falciparum infected and naïve mosquito midgut tissues showed elevated abundance of miRNAs aga-miR-989 and aga-miR-305 in infected midguts. Antagomir inhibition of aga-miR-305 increased resistance to P. falciparum infection and suppressed the midgut microbiota. Conversely, treatment of mosquitoes with an artificial aga-miR-305 mimic increased susceptibility to P. falciparum infection and resulted in expansion of midgut microbiota, suggesting that aga-miR-305 acts as a P. falciparum and gut microbiota agonist by negatively regulating the mosquito immune response. In silico prediction of aga-miR-305 target genes identified several anti-Plasmodium effectors. Our study shows that A. gambiae aga-miR-305 regulates the anti-Plasmodium response and midgut microbiota, likely through post-transcriptional modification of immune effector genes.
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Affiliation(s)
- Nathan J Dennison
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe Street, Baltimore, MD 21205, USA
| | - Omar J BenMarzouk-Hidalgo
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe Street, Baltimore, MD 21205, USA
| | - George Dimopoulos
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe Street, Baltimore, MD 21205, USA.
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Sternberg ED, Waite JL, Thomas MB. Evaluating the efficacy of biological and conventional insecticides with the new 'MCD bottle' bioassay. Malar J 2014; 13:499. [PMID: 25515850 PMCID: PMC4300847 DOI: 10.1186/1475-2875-13-499] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 12/12/2014] [Indexed: 11/17/2022] Open
Abstract
Background Control of mosquitoes requires the ability to evaluate new insecticides and to monitor resistance to existing insecticides. Monitoring tools should be flexible and low cost so that they can be deployed in remote, resource poor areas. Ideally, a bioassay should be able to simulate transient contact between mosquitoes and insecticides, and it should allow for excito-repellency and avoidance behaviour in mosquitoes. Presented here is a new bioassay, which has been designed to meet these criteria. This bioassay was developed as part of the Mosquito Contamination Device (MCD) project and, therefore, is referred to as the MCD bottle bioassay. Methods Presented here are two experiments that serve as a proof-of-concept for the MCD bottle bioassay. The experiments used four insecticide products, ranging from fast-acting, permethrin-treated, long-lasting insecticide nets (LLINs) that are already widely used for malaria vector control, to the slower acting entomopathogenic fungus, Beauveria bassiana, that is currently being evaluated as a prospective biological insecticide. The first experiment used the MCD bottle to test the effect of four different insecticides on Anopheles stephensi with a range of exposure times (1 minute, 3 minutes, 1 hour). The second experiment is a direct comparison of the MCD bottle and World Health Organization (WHO) cone bioassay that tests a subset of the insecticides (a piece of LLIN and a piece of netting coated with B. bassiana spores) and a further reduced exposure time (5 seconds) against both An. stephensi and Anopheles gambiae. Immediate knockdown and mortality after 24 hours were assessed using logistic regression and daily survival was assessed using Cox proportional hazards models. Results Across both experiments, fungus performed much more consistently than the chemical insecticides but measuring the effect of fungus required monitoring of mosquito mortality over several days to a week. Qualitatively, the MCD bottle and WHO cone performed comparably, although knockdown and 24 hour mortality tended to be higher in some, but not all, groups of mosquitoes exposed using the WHO cone. Conclusion The MCD bottle is feasible as a flexible, low-cost method for testing insecticidal materials. It is promising as a tool for testing transient contact and for capturing the effects of mosquito behavioural responses to insecticides.
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Affiliation(s)
- Eleanore D Sternberg
- Center for Infectious Disease Dynamics and Department of Entomology, Pennsylvania State University, University Park, PA, USA.
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Vantaux A, Dabiré KR, Cohuet A, Lefèvre T. A heavy legacy: offspring of malaria-infected mosquitoes show reduced disease resistance. Malar J 2014; 13:442. [PMID: 25412797 PMCID: PMC4255934 DOI: 10.1186/1475-2875-13-442] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 11/05/2014] [Indexed: 12/28/2022] Open
Abstract
Background Trans-generational effects of immune stimulation may have either adaptive (trans-generational immune priming) or non-adaptive (fitness costs) effects on offspring ability to fight pathogens. Methods Anopheles coluzzii and its natural malaria parasite Plasmodium falciparum were used to test how maternal parasite infection affected offspring resistance to the same parasite species. Results Daughters of exposed mothers had similar qualitative resistance, as measured by their ability to prevent infection, relative to those of control mothers. However, maternal disease exposure altered offspring quantitative resistance, measured as the ability to limit parasite development, with mosquitoes of infected mothers suffering slightly increased parasite intensity compared to controls. In addition, quantitative resistance was minimal in offspring of highly infected mothers, and in offspring issued from eggs produced during the early infection phase. Conclusions Plasmodium falciparum infection in An. coluzzii can have trans-generational costs, lowering quantitative resistance in offspring of infected mothers. Malaria-exposed mosquitoes might heavily invest in immune defences and thereby produce lower quality offspring that are poorly resistant. Electronic supplementary material The online version of this article (doi:10.1186/1475-2875-13-442) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Amélie Vantaux
- UMR MIVEGEC (IRD 224 - CNRS 5290 - UM1 - UM2), 911 Avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France.
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Ayala D, Ullastres A, González J. Adaptation through chromosomal inversions in Anopheles. Front Genet 2014; 5:129. [PMID: 24904633 PMCID: PMC4033225 DOI: 10.3389/fgene.2014.00129] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 04/22/2014] [Indexed: 12/29/2022] Open
Abstract
Chromosomal inversions have been repeatedly involved in local adaptation in a large number of animals and plants. The ecological and behavioral plasticity of Anopheles species-human malaria vectors-is mirrored by high amounts of polymorphic inversions. The adaptive significance of chromosomal inversions has been consistently attested by strong and significant correlations between their frequencies and a number of phenotypic traits. Here, we provide an extensive literature review of the different adaptive traits associated with chromosomal inversions in the genus Anopheles. Traits having important consequences for the success of present and future vector control measures, such as insecticide resistance and behavioral changes, are discussed.
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Affiliation(s)
- Diego Ayala
- UMR 224 MIVEGEC/BEES, IRD Montpellier, France ; Unité d'Entomologie Médicale, Centre International de Recherches Médicales de Franceville Franceville, Gabon
| | - Anna Ullastres
- Comparative and Computational Genomics, Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra) Barcelona, Spain
| | - Josefa González
- Comparative and Computational Genomics, Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra) Barcelona, Spain
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Contreras-Garduño J, Rodríguez M, Rodríguez M, Alvarado-Delgado A, Lanz-Mendoza H. Cost of immune priming within generations: trade-off between infection and reproduction. Microbes Infect 2014; 16:261-7. [DOI: 10.1016/j.micinf.2013.11.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 11/06/2013] [Accepted: 11/18/2013] [Indexed: 01/15/2023]
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Carter V, Underhill A, Baber I, Sylla L, Baby M, Larget-Thiery I, Zettor A, Bourgouin C, Langel Ü, Faye I, Otvos L, Wade JD, Coulibaly MB, Traore SF, Tripet F, Eggleston P, Hurd H. Killer bee molecules: antimicrobial peptides as effector molecules to target sporogonic stages of Plasmodium. PLoS Pathog 2013; 9:e1003790. [PMID: 24278025 PMCID: PMC3836994 DOI: 10.1371/journal.ppat.1003790] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 09/27/2013] [Indexed: 11/18/2022] Open
Abstract
A new generation of strategies is evolving that aim to block malaria transmission by employing genetically modified vectors or mosquito pathogens or symbionts that express anti-parasite molecules. Whilst transgenic technologies have advanced rapidly, there is still a paucity of effector molecules with potent anti-malaria activity whose expression does not cause detrimental effects on mosquito fitness. Our objective was to examine a wide range of antimicrobial peptides (AMPs) for their toxic effects on Plasmodium and anopheline mosquitoes. Specifically targeting early sporogonic stages, we initially screened AMPs for toxicity against a mosquito cell line and P. berghei ookinetes. Promising candidate AMPs were fed to mosquitoes to monitor adverse fitness effects, and their efficacy in blocking rodent malaria infection in Anopheles stephensi was assessed. This was followed by tests to determine their activity against P. falciparum in An. gambiae, initially using laboratory cultures to infect mosquitoes, then culminating in preliminary assays in the field using gametocytes and mosquitoes collected from the same area in Mali, West Africa. From a range of 33 molecules, six AMPs able to block Plasmodium development were identified: Anoplin, Duramycin, Mastoparan X, Melittin, TP10 and Vida3. With the exception of Anoplin and Mastoparan X, these AMPs were also toxic to an An. gambiae cell line at a concentration of 25 µM. However, when tested in mosquito blood feeds, they did not reduce mosquito longevity or egg production at concentrations of 50 µM. Peptides effective against cultured ookinetes were less effective when tested in vivo and differences in efficacy against P. berghei and P. falciparum were seen. From the range of molecules tested, the majority of effective AMPs were derived from bee/wasp venoms.
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Affiliation(s)
- Victoria Carter
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Keele, Staffordshire, United Kingdom
| | - Ann Underhill
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Keele, Staffordshire, United Kingdom
| | - Ibrahima Baber
- Malaria Research and Training Centre (MRTC), Université des Sciences, des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Lakamy Sylla
- Malaria Research and Training Centre (MRTC), Université des Sciences, des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Mounirou Baby
- Centre National de Transfusion Sanguine, Bamako, Mali
| | - Isabelle Larget-Thiery
- Institut Pasteur, Centre for Production and Infection of Anopheles (CEPIA), Parasitology and Mycology Department, Paris, France
| | - Agnès Zettor
- Institut Pasteur, Centre for Production and Infection of Anopheles (CEPIA), Parasitology and Mycology Department, Paris, France
| | - Catherine Bourgouin
- Institut Pasteur, Centre for Production and Infection of Anopheles (CEPIA), Parasitology and Mycology Department, Paris, France
| | - Ülo Langel
- Department of Neurochemistry Svante Arrhenius v. 21A, Stockholm University, Stockholm, Sweden
| | - Ingrid Faye
- Department of Molecular Bioscience, the Wenner-Gren Institute, Svante Arrhenius v. 20C, Stockholm University, Stockholm, Sweden
| | - Laszlo Otvos
- Temple University Department of Biology, Philadelphia, Pennsylvania, United States of America
| | - John D. Wade
- Howard Florey Research Laboratories, Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Mamadou B. Coulibaly
- Malaria Research and Training Centre (MRTC), Université des Sciences, des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Sekou F. Traore
- Malaria Research and Training Centre (MRTC), Université des Sciences, des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Frederic Tripet
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Keele, Staffordshire, United Kingdom
| | - Paul Eggleston
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Keele, Staffordshire, United Kingdom
- * E-mail:
| | - Hilary Hurd
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Keele, Staffordshire, United Kingdom
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Smith RC, Kizito C, Rasgon JL, Jacobs-Lorena M. Transgenic mosquitoes expressing a phospholipase A(2) gene have a fitness advantage when fed Plasmodium falciparum-infected blood. PLoS One 2013; 8:e76097. [PMID: 24098427 PMCID: PMC3788000 DOI: 10.1371/journal.pone.0076097] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 08/20/2013] [Indexed: 11/18/2022] Open
Abstract
Background Genetically modified mosquitoes have been proposed as an alternative strategy to reduce the heavy burden of malaria. In recent years, several proof-of-principle experiments have been performed that validate the idea that mosquitoes can be genetically modified to become refractory to malaria parasite development. Results We have created two transgenic lines of Anophelesstephensi, a natural vector of Plasmodium falciparum, which constitutively secrete a catalytically inactive phospholipase A2 (mPLA2) into the midgut lumen to interfere with Plasmodium ookinete invasion. Our experiments show that both transgenic lines expressing mPLA2 significantly impair the development of rodent malaria parasites, but only one line impairs the development of human malaria parasites. In addition, when fed on malaria-infected blood, mosquitoes from both transgenic lines are more fecund than non-transgenic mosquitoes. Consistent with these observations, cage experiments with mixed populations of transgenic and non-transgenic mosquitoes show that the percentage of transgenic mosquitoes increases when maintained on Plasmodium-infected blood. Conclusions Our results suggest that the expression of an anti-Plasmodium effector gene gives transgenic mosquitoes a fitness advantage when fed malaria-infected blood. These findings have important implications for future applications of transgenic mosquito technology in malaria control.
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Affiliation(s)
- Ryan C. Smith
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Christopher Kizito
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Jason L. Rasgon
- Department of Entomology, Center for Infectious Disease Dynamics and the Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Marcelo Jacobs-Lorena
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail:
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Bacteria- and IMD pathway-independent immune defenses against Plasmodium falciparum in Anopheles gambiae. PLoS One 2013; 8:e72130. [PMID: 24019865 PMCID: PMC3760850 DOI: 10.1371/journal.pone.0072130] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Accepted: 07/11/2013] [Indexed: 01/12/2023] Open
Abstract
The mosquito Anopheles gambiae uses its innate immune system to control bacterial and Plasmodium infection of its midgut tissue. The activation of potent IMD pathway-mediated anti-Plasmodium falciparum defenses is dependent on the presence of the midgut microbiota, which activate this defense system upon parasite infection through a peptidoglycan recognition protein, PGRPLC. We employed transcriptomic and reverse genetic analyses to compare the P. falciparum infection-responsive transcriptomes of septic and aseptic mosquitoes and to determine whether bacteria-independent anti-Plasmodium defenses exist. Antibiotic treated aseptic mosquitoes mounted molecular immune responses representing a variety of immune functions upon P. falciparum infection. Among other immune factors, our analysis uncovered a serine protease inhibitor (SRPN7) and Clip-domain serine protease (CLIPC2) that were transcriptionally induced in the midgut upon P. falciparum infection, independent of bacteria. We also showed that SRPN7 negatively and CLIPC2 positively regulate the anti-Plasmodium defense, independently of the midgut-associated bacteria. Co-silencing assays suggested that these two genes may function together in a signaling cascade. Neither gene was regulated, nor modulated, by infection with the rodent malaria parasite Plasmodium berghei, suggesting that SRPN7 and CLIPC2 are components of a defense system with preferential activity towards P. falciparum. Further analysis using RNA interference determined that these genes do not regulate the anti-Plasmodium defense mediated by the IMD pathway, and both factors act as agonists of the endogenous midgut microbiota, further demonstrating the lack of functional relatedness between these genes and the bacteria-dependent activation of the IMD pathway. This is the first study confirming the existence of a bacteria-independent, anti-P. falciparum defense. Further exploration of this anti-Plasmodium defense will help clarify determinants of immune specificity in the mosquito, and expose potential gene and/or protein targets for malaria intervention strategies based on targeting the parasite in the mosquito vector.
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Immunogenic and antioxidant effects of a pathogen-associated prenyl pyrophosphate in Anopheles gambiae. PLoS One 2013; 8:e73868. [PMID: 23967351 PMCID: PMC3742518 DOI: 10.1371/journal.pone.0073868] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 07/31/2013] [Indexed: 01/31/2023] Open
Abstract
Despite efficient vector transmission, Plasmodium parasites suffer great bottlenecks during their developmental stages within Anopheles mosquitoes. The outcome depends on a complex three-way interaction between host, parasite and gut bacteria. Although considerable progress has been made recently in deciphering Anopheles effector responses, little is currently known regarding the underlying microbial immune elicitors. An interesting candidate in this sense is the pathogen-derived prenyl pyrophosphate and designated phosphoantigen (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), found in Plasmodium and most eubacteria but not in higher eukaryotes. HMBPP is the most potent stimulant known of human Vγ9Vδ2 T cells, a unique lymphocyte subset that expands during several infections including malaria. In this study, we show that Vγ9Vδ2 T cells proliferate when stimulated with supernatants from intraerythrocytic stages of Plasmodium falciparum cultures, suggesting that biologically relevant doses of phosphoantigens are excreted by the parasite. Next, we used Anopheles gambiae to investigate the immune- and redox- stimulating effects of HMBPP. We demonstrate a potent activation in vitro of all but one of the signaling pathways earlier implicated in the human Vγ9Vδ2 T cell response, as p38, JNK and PI3K/Akt but not ERK were activated in the A. gambiae 4a3B cell line. Additionally, both HMBPP and the downstream endogenous metabolite isopentenyl pyrophosphate displayed antioxidant effects by promoting cellular tolerance to hydrogen peroxide challenge. When provided in the mosquito blood meal, HMBPP induced temporal changes in the expression of several immune genes. In contrast to meso-diaminopimelic acid containing peptidoglycan, HMBPP induced expression of dual oxidase and nitric oxide synthase, two key determinants of Plasmodium infection. Furthermore, temporal fluctuations in midgut bacterial numbers were observed. The multifaceted effects observed in this study indicates that HMBPP is an important elicitor in common for both Plasmodium and gut bacteria in the mosquito.
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Price I, Ermentrout B, Zamora R, Wang B, Azhar N, Mi Q, Constantine G, Faeder JR, Luckhart S, Vodovotz Y. In vivo, in vitro, and in silico studies suggest a conserved immune module that regulates malaria parasite transmission from mammals to mosquitoes. J Theor Biol 2013; 334:173-86. [PMID: 23764028 DOI: 10.1016/j.jtbi.2013.05.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 05/24/2013] [Accepted: 05/31/2013] [Indexed: 12/21/2022]
Abstract
Human malaria can be caused by the parasite Plasmodium falciparum that is transmitted by female Anopheles mosquitoes. "Immunological crosstalk" between the mammalian and anopheline hosts for Plasmodium functions to control parasite numbers. Key to this process is the mammalian cytokine transforming growth factor-β1 (TGF-β1). In mammals, TGF-β1 regulates inducible nitric oxide (NO) synthase (iNOS) both positively and negatively. In some settings, high levels of NO activate latent TGF-β1, which in turn suppresses iNOS expression. In the mosquito, ingested TGF-β1 induces A. stephensi NOS (AsNOS), which limits parasite development and which in turn is suppressed by activation of the mosquito homolog of the mitogen-activated protein kinases MEK and ERK. Computational models linking TGF-β1, AsNOS, and MEK/ERK were developed to provide insights into this complex biology. An initial Boolean model suggested that, as occurs in mammalian cells, MEK/ERK and AsNOS would oscillate upon ingestion of TGF-β1. An ordinary differential equation (ODE) model further supported the hypothesis of TGF-β1-induced multiphasic behavior of MEK/ERK and AsNOS. To achieve this multiphasic behavior, the ODE model was predicated on the presence of constant levels of TGF-β1 in the mosquito midgut. Ingested TGF-β1, however, did not exhibit this behavior. Accordingly, we hypothesized and experimentally verified that ingested TGF-β1 induces the expression of the endogenous mosquito TGF-β superfamily ligand As60A. Computational simulation of these complex, cross-species interactions suggested that TGF-β1 and NO-mediated induction of As60A expression together may act to maintain multiphasic AsNOS expression via MEK/ERK-dependent signaling. We hypothesize that multiphasic behavior as represented in this model allows the mosquito to balance the conflicting demands of parasite killing and metabolic homeostasis in the face of damaging inflammation.
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Affiliation(s)
- Ian Price
- Department of Mathematics, University of Pittsburgh, Pittsburgh, PA 15260, USA
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Pollitt LC, Churcher TS, Dawes EJ, Khan SM, Sajid M, Basáñez MG, Colegrave N, Reece SE. Costs of crowding for the transmission of malaria parasites. Evol Appl 2013; 6:617-29. [PMID: 23789029 PMCID: PMC3684743 DOI: 10.1111/eva.12048] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 12/13/2012] [Accepted: 12/13/2012] [Indexed: 01/03/2023] Open
Abstract
The utility of using evolutionary and ecological frameworks to understand the dynamics of infectious diseases is gaining increasing recognition. However, integrating evolutionary ecology and infectious disease epidemiology is challenging because within-host dynamics can have counterintuitive consequences for between-host transmission, especially for vector-borne parasites. A major obstacle to linking within- and between-host processes is that the drivers of the relationships between the density, virulence, and fitness of parasites are poorly understood. By experimentally manipulating the intensity of rodent malaria (Plasmodium berghei) infections in Anopheles stephensi mosquitoes under different environmental conditions, we show that parasites experience substantial density-dependent fitness costs because crowding reduces both parasite proliferation and vector survival. We then use our data to predict how interactions between parasite density and vector environmental conditions shape within-vector processes and onward disease transmission. Our model predicts that density-dependent processes can have substantial and unexpected effects on the transmission potential of vector-borne disease, which should be considered in the development and evaluation of transmission-blocking interventions.
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Affiliation(s)
- Laura C Pollitt
- Institute of Evolutionary Biology, University of Edinburgh Edinburgh, UK ; Center for Infectious Disease Dynamics, Pennsylvania State University University Park, PA, USA
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Holm I, Lavazec C, Garnier T, Mitri C, Riehle MM, Bischoff E, Brito-Fravallo E, Takashima E, Thiery I, Zettor A, Petres S, Bourgouin C, Vernick KD, Eiglmeier K. Diverged alleles of the Anopheles gambiae leucine-rich repeat gene APL1A display distinct protective profiles against Plasmodium falciparum. PLoS One 2012; 7:e52684. [PMID: 23285147 PMCID: PMC3532451 DOI: 10.1371/journal.pone.0052684] [Citation(s) in RCA: 9] [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: 07/19/2012] [Accepted: 11/19/2012] [Indexed: 12/23/2022] Open
Abstract
Functional studies have demonstrated a role for the Anopheles gambiae APL1A gene in resistance against the human malaria parasite, Plasmodium falciparum. Here, we exhaustively characterize the structure of the APL1 locus and show that three structurally different APL1A alleles segregate in the Ngousso colony. Genetic association combined with RNAi-mediated gene silencing revealed that APL1A alleles display distinct protective profiles against P. falciparum. One APL1A allele is sufficient to explain the protective phenotype of APL1A observed in silencing experiments. Epitope-tagged APL1A isoforms expressed in an in vitro hemocyte-like cell system showed that under assay conditions, the most protective APL1A isoform (APL1A(2)) localizes within large cytoplasmic vesicles, is not constitutively secreted, and forms only one protein complex, while a less protective isoform (APL1A(1)) is constitutively secreted in at least two protein complexes. The tested alleles are identical to natural variants in the wild A. gambiae population, suggesting that APL1A genetic variation could be a factor underlying natural heterogeneity of vector susceptibility to P. falciparum.
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Affiliation(s)
- Inge Holm
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
| | - Catherine Lavazec
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
| | - Thierry Garnier
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
| | - Christian Mitri
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
| | - Michelle M. Riehle
- Department of Microbiology, University of Minnesota, Saint Paul, Minnesota, United States of America
| | - Emmanuel Bischoff
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
| | - Emma Brito-Fravallo
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
| | - Eizo Takashima
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
| | - Isabelle Thiery
- Centre de Production et Infection des Anophèles (CEPIA), Institut Pasteur, Paris, France
| | - Agnes Zettor
- Centre de Production et Infection des Anophèles (CEPIA), Institut Pasteur, Paris, France
| | - Stephane Petres
- Centre de Production de Protéines recombinantes et d’Anticorps, Institut Pasteur, Paris, France
| | - Catherine Bourgouin
- Centre de Production et Infection des Anophèles (CEPIA), Institut Pasteur, Paris, France
| | - Kenneth D. Vernick
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
- Department of Microbiology, University of Minnesota, Saint Paul, Minnesota, United States of America
| | - Karin Eiglmeier
- Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology, CNRS Unit URA3012: Hosts, Vectors and Infectious Agents, Institut Pasteur, Paris, France
- * E-mail:
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Ubaida Mohien C, Colquhoun DR, Mathias DK, Gibbons JG, Armistead JS, Rodriguez MC, Rodriguez MH, Edwards NJ, Hartler J, Thallinger GG, Graham DR, Martinez-Barnetche J, Rokas A, Dinglasan RR. A bioinformatics approach for integrated transcriptomic and proteomic comparative analyses of model and non-sequenced anopheline vectors of human malaria parasites. Mol Cell Proteomics 2012; 12:120-31. [PMID: 23082028 PMCID: PMC3536893 DOI: 10.1074/mcp.m112.019596] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Malaria morbidity and mortality caused by both Plasmodium falciparum and Plasmodium vivax extend well beyond the African continent, and although P. vivax causes between 80 and 300 million severe cases each year, vivax transmission remains poorly understood. Plasmodium parasites are transmitted by Anopheles mosquitoes, and the critical site of interaction between parasite and host is at the mosquito's luminal midgut brush border. Although the genome of the “model” African P. falciparum vector, Anopheles gambiae, has been sequenced, evolutionary divergence limits its utility as a reference across anophelines, especially non-sequenced P. vivax vectors such as Anopheles albimanus. Clearly, technologies and platforms that bridge this substantial scientific gap are required in order to provide public health scientists with key transcriptomic and proteomic information that could spur the development of novel interventions to combat this disease. To our knowledge, no approaches have been published that address this issue. To bolster our understanding of P. vivax–An. albimanus midgut interactions, we developed an integrated bioinformatic-hybrid RNA-Seq-LC-MS/MS approach involving An. albimanus transcriptome (15,764 contigs) and luminal midgut subproteome (9,445 proteins) assembly, which, when used with our custom Diptera protein database (685,078 sequences), facilitated a comparative proteomic analysis of the midgut brush borders of two important malaria vectors, An. gambiae and An. albimanus.
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Affiliation(s)
- Ceereena Ubaida Mohien
- W Harry Feinstone Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health & Malaria Research Institute, Baltimore, Maryland 21205, USA
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Lyimo IN, Keegan SP, Ranford-Cartwright LC, Ferguson HM. The impact of uniform and mixed species blood meals on the fitness of the mosquito vector Anopheles gambiae s.s: does a specialist pay for diversifying its host species diet? J Evol Biol 2012; 25:452-60. [PMID: 22221693 DOI: 10.1111/j.1420-9101.2011.02442.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We investigated the fitness consequences of specialization in an organism whose host choice has an immense impact on human health: the African malaria vector Anopheles gambiae s.s. We tested whether this mosquito's specialism on humans can be attributed to the relative fitness benefits of specialist vs. generalist feeding strategies by contrasting their fecundity and survival on human-only and mixed host diets consisting of blood meals from humans and animals. When given only one blood meal, An. gambiae s.s. survived significantly longer on human and bovine blood, than on canine or avian blood. However, when blood fed repeatedly, there was no evidence that the fitness of An. gambiae s.s. fed a human-only diet was greater than those fed generalist diets. This suggests that the adoption of generalist host feeding strategies in An. gambiae s.s. is not constrained by intraspecific variation in the resource quality of blood from other available host species.
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Affiliation(s)
- I N Lyimo
- Environmental and Biomedical Thematic Group, Ifakara Health Institute, Ifakara, Tanzania.
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Ciota AT, Styer LM, Meola MA, Kramer LD. The costs of infection and resistance as determinants of West Nile virus susceptibility in Culex mosquitoes. BMC Ecol 2011; 11:23. [PMID: 21975028 PMCID: PMC3215953 DOI: 10.1186/1472-6785-11-23] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 10/05/2011] [Indexed: 12/03/2022] Open
Abstract
Background Understanding the phenotypic consequences of interactions between arthropod-borne viruses (arboviruses) and their mosquito hosts has direct implications for predicting the evolution of these relationships and the potential for changes in epidemiological patterns. Although arboviruses are generally not highly pathogenic to mosquitoes, pathology has at times been noted. Here, in order to evaluate the potential costs of West Nile virus (WNV) infection and resistance in a primary WNV vector, and to assess the extent to which virus-vector relationships are species-specific, we performed fitness studies with and without WNV exposure using a highly susceptible Culex pipiens mosquito colony. Specifically, we measured and compared survival, fecundity, and feeding rates in bloodfed mosquitoes that were (i) infected following WNV exposure (susceptible), (ii) uninfected following WNV exposure (resistant), or (iii) unexposed. Results In contrast to our previous findings with a relatively resistant Cx. tarsalis colony, WNV infection did not alter fecundity or blood-feeding behaviour of Cx. pipiens, yet results do indicate that resistance to infection is associated with a fitness cost in terms of mosquito survival. Conclusions The identification of species-specific differences provides an evolutionary explanation for variability in vector susceptibility to arboviruses and suggests that understanding the costs of infection and resistance are important factors in determining the potential competence of vector populations for arboviruses.
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Duncan AB, Fellous S, Kaltz O. REVERSE EVOLUTION: SELECTION AGAINST COSTLY RESISTANCE IN DISEASE-FREE MICROCOSM POPULATIONS OF PARAMECIUM CAUDATUM. Evolution 2011; 65:3462-74. [DOI: 10.1111/j.1558-5646.2011.01388.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Hume JCC, Hamilton H, Lee KL, Lehmann T. Susceptibility of Anopheles stephensi to Plasmodium gallinaceum: a trait of the mosquito, the parasite, and the environment. PLoS One 2011; 6:e20156. [PMID: 21694762 PMCID: PMC3111409 DOI: 10.1371/journal.pone.0020156] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 04/26/2011] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Vector susceptibility to Plasmodium infection is treated primarily as a vector trait, although it is a composite trait expressing the joint occurrence of the parasite and the vector with genetic contributions of both. A comprehensive approach to assess the specific contribution of genetic and environmental variation on "vector susceptibility" is lacking. Here we developed and implemented a simple scheme to assess the specific contributions of the vector, the parasite, and the environment to "vector susceptibility." To the best of our knowledge this is the first study that employs such an approach. METHODOLOGY/PRINCIPAL FINDINGS We conducted selection experiments on the vector (while holding the parasite "constant") and on the parasite (while holding the vector "constant") to estimate the genetic contributions of the mosquito and the parasite to the susceptibility of Anopheles stephensi to Plasmodium gallinaceum. We separately estimated the realized heritability of (i) susceptibility to parasite infection by the mosquito vector and (ii) parasite compatibility (transmissibility) with the vector while controlling the other. The heritabilities of vector and the parasite were higher for the prevalence, i.e., fraction of infected mosquitoes, than the corresponding heritabilities of parasite load, i.e., the number of oocysts per mosquito. CONCLUSIONS The vector's genetics (heritability) comprised 67% of "vector susceptibility" measured by the prevalence of mosquitoes infected with P. gallinaceum oocysts, whereas the specific contribution of parasite genetics (heritability) to this trait was only 5%. Our parasite source might possess minimal genetic diversity, which could explain its low heritability (and the high value of the vector). Notably, the environment contributed 28%. These estimates are relevant only to the particular system under study, but this experimental design could be useful for other parasite-host systems. The prospects and limitations of the genetic manipulation of vector populations to render the vector resistant to the parasite are better considered on the basis of this framework.
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Affiliation(s)
- Jen C. C. Hume
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Howard Hamilton
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Kevin L. Lee
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Tovi Lehmann
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- * E-mail:
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Daş G, Abel H, Humburg J, Schwarz A, Rautenschlein S, Breves G, Gauly M. Non-starch polysaccharides alter interactions between Heterakis gallinarum and Histomonas meleagridis. Vet Parasitol 2011; 176:208-16. [DOI: 10.1016/j.vetpar.2010.11.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Revised: 10/26/2010] [Accepted: 11/04/2010] [Indexed: 11/26/2022]
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Harris C, Lambrechts L, Rousset F, Abate L, Nsango SE, Fontenille D, Morlais I, Cohuet A. Polymorphisms in Anopheles gambiae immune genes associated with natural resistance to Plasmodium falciparum. PLoS Pathog 2010; 6:e1001112. [PMID: 20862317 PMCID: PMC2940751 DOI: 10.1371/journal.ppat.1001112] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 08/18/2010] [Indexed: 12/13/2022] Open
Abstract
Many genes involved in the immune response of Anopheles gambiae, the main malaria vector in Africa, have been identified, but whether naturally occurring polymorphisms in these genes underlie variation in resistance to the human malaria parasite, Plasmodium falciparum, is currently unknown. Here we carried out a candidate gene association study to identify single nucleotide polymorphisms (SNPs) associated with natural resistance to P. falciparum. A. gambiae M form mosquitoes from Cameroon were experimentally challenged with three local wild P. falciparum isolates. Statistical associations were assessed between 157 SNPs selected from a set of 67 A. gambiae immune-related genes and the level of infection. Isolate-specific associations were accounted for by including the effect of the isolate in the analysis. Five SNPs were significantly associated to the infection phenotype, located within or upstream of AgMDL1, CEC1, Sp PPO activate, Sp SNAKElike, and TOLL6. Low overall and local linkage disequilibrium indicated high specificity in the loci found. Association between infection phenotype and two SNPs was isolate-specific, providing the first evidence of vector genotype by parasite isolate interactions at the molecular level. Four SNPs were associated to either oocyst presence or load, indicating that the genetic basis of infection prevalence and intensity may differ. The validity of the approach was verified by confirming the functional role of Sp SNAKElike in gene silencing assays. These results strongly support the role of genetic variation within or near these five A. gambiae immune genes, in concert with other genes, in natural resistance to P. falciparum. They emphasize the need to distinguish between infection prevalence and intensity and to account for the genetic specificity of vector-parasite interactions in dissecting the genetic basis of Anopheles resistance to human malaria. Anopheles gambiae is the main malaria vector in Africa, transmitting the parasite when it blood feeds on human hosts. The parasite undergoes several developmental stages in the mosquito to complete its life cycle, during which time it is confronted by the mosquito's immune system. The resistance of mosquitoes to malaria infection is highly variable in wild populations and is known to be under strong genetic control, but to date the specific genes responsible for this variation remain to be identified. The present study uncovers variations in A. gambiae immune genes that are associated with natural resistance to Plasmodium falciparum, the deadliest human malaria parasite. The association of some mosquito genetic loci with the level of infection depended on the P. falciparum isolate, suggesting that resistance is determined by interactions between the genome of the mosquito and that of the parasite. This finding highlights the need to account for the natural genetic diversity of malaria parasites in future research on vector-parasite interactions. The loci uncovered in this study are potential targets for developing novel malaria control strategies based on natural mosquito resistance mechanisms.
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Affiliation(s)
- Caroline Harris
- Characterization and Control of Vector Populations, Institut de Recherche pour le Développement, Montpellier, France.
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Scolari F, Siciliano P, Gabrieli P, Gomulski LM, Bonomi A, Gasperi G, Malacrida AR. Safe and fit genetically modified insects for pest control: from lab to field applications. Genetica 2010; 139:41-52. [PMID: 20725766 DOI: 10.1007/s10709-010-9483-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 08/07/2010] [Indexed: 01/10/2023]
Abstract
Insect transgenesis is continuously being improved to increase the efficacy of population suppression and replacement strategies directed to the control of insect species of economic and sanitary interest. An essential prerequisite for the success of both pest control applications is that the fitness of the transformant individuals is not impaired, so that, once released in the field, they can efficiently compete with or even out-compete their wild-type counterparts for matings in order to reduce the population size, or to spread desirable genes into the target population. Recent research has shown that the production of fit and competitive transformants can now be achieved and that transgenes may not necessarily confer a fitness cost. In this article we review the most recent published results of the fitness assessment of different transgenic insect lines and underline the necessity to fulfill key requirements of ecological safety. Fitness evaluation studies performed in field cages and medium/large-scale rearing will validate the present encouraging laboratory results, giving an indication of the performance of the transgenic insect genotype after release in pest control programmes.
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Affiliation(s)
- F Scolari
- Department of Animal Biology, University of Pavia, Pavia, Italy
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Cohuet A, Harris C, Robert V, Fontenille D. Evolutionary forces on Anopheles: what makes a malaria vector? Trends Parasitol 2010; 26:130-6. [PMID: 20056485 DOI: 10.1016/j.pt.2009.12.001] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2009] [Revised: 10/23/2009] [Accepted: 12/11/2009] [Indexed: 12/22/2022]
Abstract
In human malaria, transmission intensity is highly dependent on the vectorial capacity and competence of local mosquitoes. Most mosquitoes are dead ends for the parasite, and only limited ranges of Anopheles are able to transmit Plasmodium to humans. Research to understand the determinants of vectorial capacity and competence has greatly progressed in recent years; however, some aspects have been overlooked and the evolutionary pressures that affect them often neglected. Here, we review key factors of vectorial capacity and competence in Anopheles, with a particular focus on the most important malaria vector Anopheles gambiae. We aim to point out selection pressures exerted by Plasmodium on Anopheles to improve its own transmission and discuss how the parasite might shape the vector to its benefit.
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Affiliation(s)
- Anna Cohuet
- Institut de Recherche pour le Développement, UR016, Characterization and control of vector populations, Montpellier, France.
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Smith RC, Jacobs-Lorena M. Plasmodium-Mosquito Interactions: A Tale of Roadblocks and Detours. ADVANCES IN INSECT PHYSIOLOGY 2010; 39:119-149. [PMID: 23729903 PMCID: PMC3666160 DOI: 10.1016/b978-0-12-381387-9.00004-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Affiliation(s)
- Ryan C Smith
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, The Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
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Sharma A, Parasher H, Singh O, Adak T. Species B of Anopheles culicifacies (Diptera: Culicidae) is reproductively less fit than species A and C of the complex. Acta Trop 2009; 112:316-9. [PMID: 19679093 DOI: 10.1016/j.actatropica.2009.08.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Revised: 07/31/2009] [Accepted: 08/05/2009] [Indexed: 10/20/2022]
Abstract
Anopheles culicifacies, the most important malaria vector of peninsular India exist as a complex of five sibling species. The member species of the complex have various biological differences including their susceptibility to malaria parasites. The present attempt is made to study and compare the fecundity of the differentially susceptible members of the An. culicifacies complex. Gravid female mosquitoes of species A, B and C were allowed to lay their eggs individually during first and second gonotrophic cycle. The eggs were counted after hatching and categorized as 'hatched eggs', 'unhatched eggs', 'embryonated eggs', 'unembryonated eggs' and 'non/partially melanized eggs'. The data was analyzed using Student's t test, ANOVA, Chi-square and Pearson's correlation analysis. All females that were visually categorized as 'gravid' did not lay eggs. Species C laid maximum number of eggs per female. The eggs laid per female mosquito of each species were found to be significantly higher during second gonotrophic cycle as compared with the first gonotrophic cycle. The eggs hatched per female in species C were found to be significantly higher than that of species A and B. The poor-vector species B mosquitoes were found to be the least fecund among the members of the species complex. The unembryonated eggs constitute the biggest proportion of the unhatched eggs in species A, B and C of the species complex.
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Hurd H. Evolutionary drivers of parasite-induced changes in insect life-history traits from theory to underlying mechanisms. ADVANCES IN PARASITOLOGY 2009; 68:85-110. [PMID: 19289191 DOI: 10.1016/s0065-308x(08)00604-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Many hosts are able to tolerate infection by altering life-history traits that are traded-off one against another. Here the reproductive fitness of insect hosts and vectors is reviewed in the context of theories concerning evolutionary mechanisms driving such alterations. These include the concepts that changes in host reproductive fitness are by-products of infection, parasite manipulations, host adaptations, mafia-like strategies or host compensatory responses. Two models are examined in depth, a tapeworm/beetle association, Hymenolepis diminuta/Tenebrio molitor and malaria infections in anopheline mosquitoes. Parasite-induced impairment of vitellogenesis ultimately leads to a decrease in female reproductive success in both cases, though by different means. Evidence is put forwards for both a manipulator molecule of parasite origin and for host-initiated regulation. These models are backed by other examples in which mechanisms underlying fecundity reduction or fecundity compensation are explored. It is concluded that evolutionary theories must be supported by empirical evidence gained from studying molecular, biochemical and physiological mechanisms underlying changes in host life-history traits, ideally using organisms that have evolved together and that are in their natural environment.
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Affiliation(s)
- Hilary Hurd
- Institute for Science and Technology in Medicine, Centre for Applied Entomology and Parasitilogy, School of life Sciences, Keele University, United Kingdom
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