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Domingues LN, Bendele KG, Halos L, Moreno Y, Epe C, Figueiredo M, Liebstein M, Guerrero FD. Identification of anti-horn fly vaccine antigen candidates using a reverse vaccinology approach. Parasit Vectors 2021; 14:442. [PMID: 34479607 PMCID: PMC8414034 DOI: 10.1186/s13071-021-04938-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 08/09/2021] [Indexed: 01/01/2023] Open
Abstract
Background The horn fly, Haematobia irritans irritans, causes significant production losses to the cattle industry. Horn fly control relies on insecticides; however, alternative control methods such as vaccines are needed due to the fly's capacity to quickly develop resistance to insecticides, and the pressure for eco-friendly options. Methods We used a reverse vaccinology approach comprising three vaccine prediction and 11 annotation tools to evaluate and rank 79,542 translated open reading frames (ORFs) from the horn fly's transcriptome, and selected 10 transcript ORFs as vaccine candidates for expression in Pichia pastoris. The expression of the 10 selected transcripts and the proteins that they encoded were investigated in adult flies by reverse transcription polymerase chain reaction (RT-PCR) and mass spectrometry, respectively. Then, we evaluated the immunogenicity of a vaccine candidate in an immunization trial and the antigen’s effects on horn fly mortality and fecundity in an in vitro feeding assay. Results Six of the ten vaccine candidate antigens were successfully expressed in P. pastoris. RT-PCR confirmed the expression of all six ORFs in adult fly RNA. One of the vaccine candidate antigens, BI-HS009, was expressed in sufficient quantity for immunogenicity and efficacy trials. The IgG titers of animals vaccinated with BI-HS009 plus adjuvant were significantly higher than those of animals vaccinated with buffer plus adjuvant only from days 42 to 112, with a peak on day 56. Progeny of horn flies feeding upon blood from animals vaccinated with BI-HS009 plus adjuvant collected on day 56 had 63% lower pupariation rate and 57% lower adult emergence than the control group (ANOVA: F(1, 6) = 8.221, P = 0.028 and F(1, 6) = 8.299, P = 0.028, respectively). Conclusions The reverse vaccinology approach streamlined the discovery process by prioritizing possible vaccine antigen candidates. Through a thoughtful process of selection and in vivo and in vitro evaluations, we were able to identify a promising antigen for an anti-horn fly vaccine. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-04938-5.
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Affiliation(s)
- Luísa N Domingues
- USDA-ARS Knipling-Bushland U. S. Livestock Insects Research Lab, 2700 Fredericksburg Road, Kerrville, TX, USA. .,Texas A&M University, Department of Entomology, 2475 TAMU, College Station, TX, USA.
| | - Kylie G Bendele
- USDA-ARS Knipling-Bushland U. S. Livestock Insects Research Lab, 2700 Fredericksburg Road, Kerrville, TX, USA.
| | - Lénaïg Halos
- Boehringer Ingelheim Animal Health, 29 Avenue Tony Garnier, 69007, Lyon, France.,Bill and Melinda Gates Foundation, Seattle, WA, USA
| | - Yovany Moreno
- Boehringer Ingelheim Animal Health, Pharmaceutical Discovery and Research, 3239 Satellite Blvd. Bldg. 600, Duluth, GA, USA
| | - Christian Epe
- Boehringer Ingelheim Animal Health, Pharmaceutical Discovery and Research, 3239 Satellite Blvd. Bldg. 600, Duluth, GA, USA
| | - Monica Figueiredo
- Boehringer Ingelheim Animal Health, Pharmaceutical Discovery and Research, 3239 Satellite Blvd. Bldg. 600, Duluth, GA, USA
| | - Martin Liebstein
- Boehringer Ingelheim Animal Health Missouri Research Center, 6498 Jade Rd, Fulton, MO, USA
| | - Felix D Guerrero
- USDA-ARS Knipling-Bushland U. S. Livestock Insects Research Lab, 2700 Fredericksburg Road, Kerrville, TX, USA
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Abstract
Sarcoptes scabiei is a causative organism for scabies that affects an estimated global population of 300 million and remains a disease of significant concern. Recently, a number of potential drug targets were identified for scabies, including hydrolytic enzymes, inactivated paralogues of hydrolytic enzymes, inhibitors of host proteolytic enzymes and other proteins of interest. These discoveries remain confined to academic laboratories and institutions, failing to attract interest from researchers in commercial drug development. Here, we summarize the latest developments in the scabies mite biology and the drug targets that were subsequently identified, and we propose several peptide and nonpeptide ligands targeting the hot spots for protein-protein interactions. We also identify gaps in the development of ligands as inhibitors or modulators of these macromolecules.
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Ribeiro JM, Debat HJ, Boiani M, Ures X, Rocha S, Breijo M. An insight into the sialome, mialome and virome of the horn fly, Haematobia irritans. BMC Genomics 2019; 20:616. [PMID: 31357943 PMCID: PMC6664567 DOI: 10.1186/s12864-019-5984-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/19/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The horn fly (Haematobia irritans) is an obligate blood feeder that causes considerable economic losses in livestock industries worldwide. The control of this cattle pest is mainly based on insecticides; unfortunately, in many regions, horn flies have developed resistance. Vaccines or biological control have been proposed as alternative control methods, but the available information about the biology or physiology of this parasite is rather scarce. RESULTS We present a comprehensive description of the salivary and midgut transcriptomes of the horn fly (Haematobia irritans), using deep sequencing achieved by the Illumina protocol, as well as exploring the virome of this fly. Comparison of the two transcriptomes allow for identification of uniquely salivary or uniquely midgut transcripts, as identified by statistically differential transcript expression at a level of 16 x or more. In addition, we provide genomic highlights and phylogenetic insights of Haematobia irritans Nora virus and present evidence of a novel densovirus, both associated to midgut libraries of H. irritans. CONCLUSIONS We provide a catalog of protein sequences associated with the salivary glands and midgut of the horn fly that will be useful for vaccine design. Additionally, we discover two midgut-associated viruses that infect these flies in nature. Future studies should address the prevalence, biological effects and life cycles of these viruses, which could eventually lead to translational work oriented to the control of this economically important cattle pest.
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Affiliation(s)
- J. M. Ribeiro
- Section of Vector Biology, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, 12735 Twinbrook Parkway Room 3E28, Rockville, MD 20852 USA
| | - Humberto Julio Debat
- Instituto de Patología Vegetal, Centro de Investigaciones Agropecuarias, Instituto Nacional de Tecnología Agropecuaria (IPAVE-CIAP-INTA), Córdoba, Argentina
| | - M. Boiani
- Unidad de Reactivos y Biomodelos de Experimentación, Facultad de Medicina, Universidad de la República, Gral. Flores, 2125 Montevideo, Uruguay
| | - X. Ures
- Unidad de Reactivos y Biomodelos de Experimentación, Facultad de Medicina, Universidad de la República, Gral. Flores, 2125 Montevideo, Uruguay
| | - S. Rocha
- Unidad de Reactivos y Biomodelos de Experimentación, Facultad de Medicina, Universidad de la República, Gral. Flores, 2125 Montevideo, Uruguay
| | - M. Breijo
- Unidad de Reactivos y Biomodelos de Experimentación, Facultad de Medicina, Universidad de la República, Gral. Flores, 2125 Montevideo, Uruguay
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Stutzer C, Richards SA, Ferreira M, Baron S, Maritz-Olivier C. Metazoan Parasite Vaccines: Present Status and Future Prospects. Front Cell Infect Microbiol 2018; 8:67. [PMID: 29594064 PMCID: PMC5859119 DOI: 10.3389/fcimb.2018.00067] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 02/26/2018] [Indexed: 12/21/2022] Open
Abstract
Eukaryotic parasites and pathogens continue to cause some of the most detrimental and difficult to treat diseases (or disease states) in both humans and animals, while also continuously expanding into non-endemic countries. Combined with the ever growing number of reports on drug-resistance and the lack of effective treatment programs for many metazoan diseases, the impact that these organisms will have on quality of life remain a global challenge. Vaccination as an effective prophylactic treatment has been demonstrated for well over 200 years for bacterial and viral diseases. From the earliest variolation procedures to the cutting edge technologies employed today, many protective preparations have been successfully developed for use in both medical and veterinary applications. In spite of the successes of these applications in the discovery of subunit vaccines against prokaryotic pathogens, not many targets have been successfully developed into vaccines directed against metazoan parasites. With the current increase in -omics technologies and metadata for eukaryotic parasites, target discovery for vaccine development can be expedited. However, a good understanding of the host/vector/pathogen interface is needed to understand the underlying biological, biochemical and immunological components that will confer a protective response in the host animal. Therefore, systems biology is rapidly coming of age in the pursuit of effective parasite vaccines. Despite the difficulties, a number of approaches have been developed and applied to parasitic helminths and arthropods. This review will focus on key aspects of vaccine development that require attention in the battle against these metazoan parasites, as well as successes in the field of vaccine development for helminthiases and ectoparasites. Lastly, we propose future direction of applying successes in pursuit of next generation vaccines.
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Affiliation(s)
- Christian Stutzer
- Tick Vaccine Group, Department of Genetics, University of Pretoria, Pretoria, South Africa
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Gutiérrez-Cabrera AE, Córdoba-Aguilar A, Zenteno E, Lowenberger C, Espinoza B. Origin, evolution and function of the hemipteran perimicrovillar membrane with emphasis on Reduviidae that transmit Chagas disease. BULLETIN OF ENTOMOLOGICAL RESEARCH 2016; 106:279-291. [PMID: 26639621 DOI: 10.1017/s0007485315000929] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The peritrophic matrix is a chitin-protein structure that envelops the food bolus in the midgut of the majority of insects, but is absent in some groups which have, instead, an unusual extra-cellular lipoprotein membrane named the perimicrovillar membrane. The presence of the perimicrovillar membrane (PMM) allows these insects to exploit restricted ecological niches during all life stages. It is found only in some members of the superorder Paraneoptera and many of these species are of medical and economic importance. In this review we present an overview of the midgut and the digestive system of insects with an emphasis on the order Paraneoptera and differences found across phylogenetic groups. We discuss the importance of the PMM in Hemiptera and the apparent conservation of this structure among hemipteran groups, suggesting that the basic mechanism of PMM production is the same for different hemipteran species. We propose that the PMM is intimately involved in the interaction with parasites and as such should be a target for biological and chemical control of hemipteran insects of economic and medical importance.
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Affiliation(s)
- A E Gutiérrez-Cabrera
- Departamento de Inmunología,Instituto de Investigaciones Biomedicas,Universidad Nacional Autónoma de México,Apdo. 70228,Circuito Exterior,Ciudad Universitaria,04510,Coyoacán,Distrito Federal,México
| | - A Córdoba-Aguilar
- Departamento de Ecología Evolutiva,Instituto de Ecología,Universidad Nacional Autónoma de México,Apdo. P. 70-275,Circuito Exterior,Ciudad Universitaria,04510,Coyoacán,Distrito Federal,Mexico
| | - E Zenteno
- Departamento de Bioquímica,Facultad de Medicina,Universidad Nacional Autónoma de México,Ciudad Universitaria,04510 D.F.,Mexico
| | - C Lowenberger
- Department of Biological Sciences,Simon Fraser University,Burnaby, B.C., V5A 1S6,Canada
| | - B Espinoza
- Departamento de Inmunología,Instituto de Investigaciones Biomedicas,Universidad Nacional Autónoma de México,Apdo. 70228,Circuito Exterior,Ciudad Universitaria,04510,Coyoacán,Distrito Federal,México
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Sandoval-Mojica AF, Scharf ME. GUT GENES ASSOCIATED WITH THE PERITROPHIC MATRIX IN Reticulitermes flavipes (Blattodea: Rhinotermitidae): IDENTIFICATION AND CHARACTERIZATION. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2016; 92:127-142. [PMID: 27087028 DOI: 10.1002/arch.21325] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The peritrophic matrix (PM) is an acellular structure that lines the gut of most insects. It is an attractive target for pest management strategies because of its close involvement in digestive processes and role as a barrier against pathogens and toxins. The purpose of this study was to identify and characterize the genes that translate for principal components of the Reticulitermes flavipes PM. Genes encoding a gut chitin synthase (CHS), two proteins with peritrophin-A domains, and a chitin deacetylase were identified from an R. flavipes symbiont-free gut cDNA library, a pyrosequencing study of termite lignocellulose digestion, and a metatranscriptomic analysis of R. flavipes fed on agricultural biomass. Quantitative expression analysis of the identified genes, in the termite digestive tract, revealed that the transcripts coding for a CHS (RfCHSB) and the proteins with peritrophin-A domains (RfPPAD1 and RfPPAD2) were predominantly expressed in the midgut, suggesting an association with the PM. The peritrophin identity of the RfPPAD2 gene was confirmed by immunodetection of its translated peptide in the midgut and PM. The discovery and characterization of PM components of R. flavipes provides a basis for further investigation of the viability of this structure as a target for candidate termiticides.
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Affiliation(s)
| | - Michael E Scharf
- Department of Entomology, Purdue University, West Lafayette, Indiana, USA
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7
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Torres L, Almazán C, Ayllón N, Galindo RC, Rosario-Cruz R, Quiroz-Romero H, de la Fuente J. Functional genomics of the horn fly, Haematobia irritans (Linnaeus, 1758). BMC Genomics 2011; 12:105. [PMID: 21310032 PMCID: PMC3045961 DOI: 10.1186/1471-2164-12-105] [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: 06/07/2010] [Accepted: 02/10/2011] [Indexed: 12/27/2022] Open
Abstract
Background The horn fly, Haematobia irritans (Linnaeus, 1758) (Diptera: Muscidae) is one of the most important ectoparasites of pastured cattle. Horn flies infestations reduce cattle weight gain and milk production. Additionally, horn flies are mechanical vectors of different pathogens that cause disease in cattle. The aim of this study was to conduct a functional genomics study in female horn flies using Expressed Sequence Tags (EST) analysis and RNA interference (RNAi). Results A cDNA library was made from whole abdominal tissues collected from partially fed adult female horn flies. High quality horn fly ESTs (2,160) were sequenced and assembled into 992 unigenes (178 contigs and 814 singlets) representing molecular functions such as serine proteases, cell metabolism, mitochondrial function, transcription and translation, transport, chromatin structure, vitellogenesis, cytoskeleton, DNA replication, cell response to stress and infection, cell proliferation and cell-cell interactions, intracellular trafficking and secretion, and development. Functional analyses were conducted using RNAi for the first time in horn flies. Gene knockdown by RNAi resulted in higher horn fly mortality (protease inhibitor functional group), reduced oviposition (vitellogenin, ferritin and vATPase groups) or both (immune response and 5'-NUC groups) when compared to controls. Silencing of ubiquitination ESTs did not affect horn fly mortality and ovisposition while gene knockdown in the ferritin and vATPse functional groups reduced mortality when compared to controls. Conclusions These results advanced the molecular characterization of this important ectoparasite and suggested candidate protective antigens for the development of vaccines for the control of horn fly infestations.
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Affiliation(s)
- Lorena Torres
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Tamaulipas, Km, 5 carretera Victoria-Mante, CP 87000 Ciudad Victoria, Tamaulipas, Mexico
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Oyarzún MP, Quiroz A, Birkett MA. Insecticide resistance in the horn fly: alternative control strategies. MEDICAL AND VETERINARY ENTOMOLOGY 2008; 22:188-202. [PMID: 18816268 DOI: 10.1111/j.1365-2915.2008.00733.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The horn fly, Haematobia irritans (Linnaeus 1758) (Diptera: Muscidae) is one of the most widespread and economically important pests of cattle. Although insecticides have been used for fly control, success has been limited because of the development of insecticide resistance in all countries where the horn fly is found. This problem, along with public pressure for insecticide-free food and the prohibitive cost of developing new classes of compounds, has driven the investigation of alternative control methods that minimize or avoid the use of insecticides. This review provides details of the economic impact of horn flies, existing insecticides used for horn fly control and resistance mechanisms. Current research on new methods of horn fly control based on resistant cattle selection, semiochemicals, biological control and vaccines is also discussed.
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Affiliation(s)
- M P Oyarzún
- Laboratorio Química Ecológica, Departamento de Ciencias Químicas, Universidad de La Frontera, Temuco, Chile
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9
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Abstract
Ectoparasites of livestock are of great economic and social importance but their effective control remains difficult. The feasibility of vaccination as a novel control measure was established over a decade ago with the commercial release of a recombinant vaccine against the cattle tick Boophilus microplus. Since then, research has continued on ticks and other ectoparasites. While some ectoparasite species will undoubtedly be refractory to immunological control, for others there has been a steady accumulation of knowledge of partially protective antigens, now accelerating through the application of genomic technologies. Nevertheless, progress towards usable, commercially available vaccines has been limited by a number of factors. The number of highly effective antigens is still very small. Although some classes of antigen have been investigated in more detail than others, we have no systematic knowledge of what distinguishes an effective antigen. Much hope has been placed on the potential of multi-antigen mixtures to deliver the efficacy required of a successful vaccine but with little experimental evidence. The application of current knowledge across parasite and host species needs to be explored but little has been done. In most cases, the path to commercial delivery is uncertain. Although many constraints and challenges remain, the need for vaccines and our capacity to develop them can only increase.
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Affiliation(s)
- P Willadsen
- CSIRO Livestock Industries, Queensland Bioscience Precinct, 306 Carmody Road, St Lucia QLD 4067 Australia.
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Bautista CR, Giles I, Montenegro N, Figueroa JV. Immunization of Bovines with Concealed Antigens fromHaematobia irritans. Ann N Y Acad Sci 2004; 1026:284-8. [PMID: 15604507 DOI: 10.1196/annals.1307.044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
To evaluate an immunization procedure using antigens from Haematobia irritans intestine (AgHiI), four bovines (group I) were inoculated with AgHiI mixed with Freund's incomplete adjuvant containing Lactobacillus casei, three bovines (group II) received AgHiI, and three bovines (group III) received saline solution. At day 35, blood was collected from each animal to feed H. irritans flies. There was no difference in the fly mortality observed in the three groups. The percentage of reduction of eggs oviposited by each female in 8 days (%RE), as compared with group III, was 29.45 for group I and 11.02 for group II. Antibody levels (AbL) to AgHiI were higher in group I than in groups II and III. A high correlation between %RE and AbL was observed.
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Gaines PJ, Walmsley SJ, Wisnewski N. Cloning and characterization of five cDNAs encoding peritrophin-A domains from the cat flea, Ctenocephalides felis. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2003; 33:1061-1073. [PMID: 14563358 DOI: 10.1016/s0965-1748(03)00096-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Five cDNAs encoding peritrophin-A domains were identified as expressed sequence tags (ESTs) from flea hindgut and Malpighian tubule (HMT) cDNA libraries. The full-length cDNAs for each were subsequently isolated and sequenced. Three of the encoded proteins were similar to published peritrophin sequences, and thus were called "peritrophin-like", or PL1, PL2, and PL3. The other two sequences had similarity to both mucin and peritrophin proteins, and were called "mucin/peritrophin-like", or MPL1 and MPL2. The predicted protein sequences encoded by these cDNAs all contained a signal sequence and one or more peritrophin-A domains, which have been shown in other proteins to bind chitin. Aside from the peritrophin-A domains, the sequences shared little or no similarity to each other or to other proteins in the GenBank non-redundant database. The predicted protein sequences were variable in size, ranging in length from 81 to 453 amino acids. The two MPL proteins contained putative N-linked and O-linked glycosylation sites, including a region of seven nearly perfect tandem repeats in the MPL1 protein sequence. Northern blot analysis of different flea lifestages and fed adult timepoints showed distinct mRNA expression patterns for each gene, although all five transcripts were primarily or exclusively detected in the HMT tissues in adults. The PL1 protein was detected by immuno-blot in soluble and insoluble protein extracts from unfed and fed adult fleas. The PL1 protein from the insoluble fractions appeared to be approximately 1 kDa larger than the PL1 protein from the soluble protein fractions. Immunohistochemistry performed on flea thin sections revealed that the PL1 protein was detected in the Malpighian tubules, hindgut, rectum, and trachea. Unpurified native PL1 protein from both soluble and insoluble protein fractions was tested for chitin-binding activity but did not bind to chitin under the conditions tested. These results show that the flea peritrophin-like proteins may have biological functions that are distinct from the peritrophic matrix and from the binding of chitin.
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Affiliation(s)
- Patrick J Gaines
- Heska Corporation, 1613 Prospect Parkway, Fort Collins, CO, USA.
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Foy BD, Magalhaes T, Injera WE, Sutherland I, Devenport M, Thanawastien A, Ripley D, Cárdenas-Freytag L, Beier JC. Induction of mosquitocidal activity in mice immunized with Anopheles gambiae midgut cDNA. Infect Immun 2003; 71:2032-40. [PMID: 12654823 PMCID: PMC152092 DOI: 10.1128/iai.71.4.2032-2040.2003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vaccines that induce mosquito-killing (mosquitocidal) activity could substantially reduce the transmission of certain mosquito-borne diseases, especially vaccines against African malaria vectors, such as the mosquito Anopheles gambiae. To generate and characterize antimosquito immunity we immunized groups of mice with two individual A. gambiae midgut cDNAs, Ag-Aper1 (a secreted peritrophic matrix protein) and AgMuc1 (a midgut-bound mucin), and an A. gambiae midgut cDNA library from blood-fed mosquitoes. We observed significantly increased mortality among mosquitoes that fed on either the AgMuc1- or the cDNA library-immunized mice compared to that of controls, but no differences were observed among those fed on Ag-Aper1-immunized mice. Analysis of the humoral and cellular immune responses from mice showed that the induced mosquitocidal effect was associated with immune profiles characterized by elevated tumor necrosis factor alpha and gamma interferon cytokine levels and very low antibody titers. Furthermore, an additional immunization of cDNA library-immunized mice with midgut protein shifted immunity toward a Th2-type immune response, characterized by elevated antibody titers and high interleukin-5 and interleukin-10 cytokine levels; importantly, mosquitoes feeding on these mice exhibited no undue mortality. Finally, when immune sera was ingested by mosquitoes through a membrane feeder, no effect on mosquito mortality was observed, indicating that serum factors alone were not responsible for the mosquitocidal effect. Our results demonstrate that mosquitocidal immunity in mice can be consistently generated by midgut cDNA immunization and suggest this cDNA-induced mosquitocidal immunity is cell mediated.
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Affiliation(s)
- B D Foy
- Department of Tropical Medicine, Tulane University, New Orleans, Louisiana, USA.
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