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1.
Genetics ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529759

RESUMO

FungiDB (https://fungidb.org) serves as a valuable online resource that seamlessly integrates genomic and related large-scale data for a wide range of fungal and oomycete species. As an integral part of the VEuPathDB Bioinformatics Resource Center (https://veupathdb.org), FungiDB continually integrates both published and unpublished data addressing various aspects of fungal biology. Established in early 2011, the database has evolved to support 674 datasets. The datasets include over 300 genomes spanning various taxa (e.g. Ascomycota, Basidiomycota, Blastocladiomycota, Chytridiomycota, Mucoromycota, as well as Albuginales, Peronosporales, Pythiales, and Saprolegniales). In addition to genomic assemblies and annotation, over 300 extra datasets encompassing diverse information, such as expression and variation data, are also available. The resource also provides an intuitive web-based interface, facilitating comprehensive approaches to data mining and visualization. Users can test their hypotheses and navigate through omics-scale datasets using a built-in search strategy system. Moreover, FungiDB offers capabilities for private data analysis via the integrated VEuPathDB Galaxy platform. FungiDB also permits genome improvements by capturing expert knowledge through the User Comments system and the Apollo genome annotation editor for structural and functional gene curation. FungiDB facilitates data exploration and analysis and contributes to advancing research efforts by capturing expert knowledge for fungal and oomycete species.

2.
Parasit Vectors ; 17(1): 19, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38217054

RESUMO

BACKGROUND: Understanding aspects related to the physiology and capacity of vectors is essential for effectively controlling vector-borne diseases. The sand fly Lutzomyia longipalpis has great importance in medical entomology for disseminating Leishmania parasites, the causative agent of Leishmaniasis, one of the main neglected diseases listed by the World Health Organization (WHO). In this respect, it is necessary to evaluate the transmission potential of this species and the success of vector control interventions. Near-infrared spectroscopy (NIRS) has been used to estimate the age of mosquitoes in different conditions (laboratory, semi-field, and conservation), taxonomic analysis, and infection detection. However, no studies are using NIRS for sand flies. METHODS: In this study, we developed analytic models to estimate the age of L. longipalpis adults under laboratory conditions, identify their copulation state, and evaluate their gonotrophic cycle and diet. RESULTS: Sand flies were classified with an accuracy of 58-82% in 3 age groups and 82-92% when separating them into young (<8 days) or old (>8 days) insects. The classification between mated and non-mated sandflies was 98-100% accurate, while the percentage of hits of females that had already passed the first gonotrophic cycle was only 59%. CONCLUSIONS: We consider the age and copula estimation results very promising, as they provide essential aspects of vector capacity assessment, which can be obtained quickly and at a lower cost with NIRS.


Assuntos
Leishmania , Leishmaniose , Phlebotomus , Psychodidae , Feminino , Animais , Psychodidae/parasitologia , Espectroscopia de Luz Próxima ao Infravermelho , Mosquitos Vetores , Leishmania/fisiologia
3.
Nucleic Acids Res ; 52(D1): D808-D816, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37953350

RESUMO

The Eukaryotic Pathogen, Vector and Host Informatics Resource (VEuPathDB, https://veupathdb.org) is a Bioinformatics Resource Center funded by the National Institutes of Health with additional funding from the Wellcome Trust. VEuPathDB supports >600 organisms that comprise invertebrate vectors, eukaryotic pathogens (protists and fungi) and relevant free-living or non-pathogenic species or hosts. Since 2004, VEuPathDB has analyzed omics data from the public domain using contemporary bioinformatic workflows, including orthology predictions via OrthoMCL, and integrated the analysis results with analysis tools, visualizations, and advanced search capabilities. The unique data mining platform coupled with >3000 pre-analyzed data sets facilitates the exploration of pertinent omics data in support of hypothesis driven research. Comparisons are easily made across data sets, data types and organisms. A Galaxy workspace offers the opportunity for the analysis of private large-scale datasets and for porting to VEuPathDB for comparisons with integrated data. The MapVEu tool provides a platform for exploration of spatially resolved data such as vector surveillance and insecticide resistance monitoring. To address the growing body of omics data and advances in laboratory techniques, VEuPathDB has added several new data types, searches and features, improved the Galaxy workspace environment, redesigned the MapVEu interface and updated the infrastructure to accommodate these changes.


Assuntos
Biologia Computacional , Eucariotos , Animais , Biologia Computacional/métodos , Invertebrados , Bases de Dados Factuais
4.
PLoS Negl Trop Dis ; 17(1): e0011058, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656904

RESUMO

Parasitic diseases caused by kinetoplastid parasites are a burden to public health throughout tropical and subtropical regions of the world. TriTrypDB (https://tritrypdb.org) is a free online resource for data mining of genomic and functional data from these kinetoplastid parasites and is part of the VEuPathDB Bioinformatics Resource Center (https://veupathdb.org). As of release 59, TriTrypDB hosts 83 kinetoplastid genomes, nine of which, including Trypanosoma brucei brucei TREU927, Trypanosoma cruzi CL Brener and Leishmania major Friedlin, undergo manual curation by integrating information from scientific publications, high-throughput assays and user submitted comments. TriTrypDB also integrates transcriptomic, proteomic, epigenomic, population-level and isolate data, functional information from genome-wide RNAi knock-down and fluorescent tagging, and results from automated bioinformatics analysis pipelines. TriTrypDB offers a user-friendly web interface embedded with a genome browser, search strategy system and bioinformatics tools to support custom in silico experiments that leverage integrated data. A Galaxy workspace enables users to analyze their private data (e.g., RNA-sequencing, variant calling, etc.) and explore their results privately in the context of publicly available information in the database. The recent addition of an annotation platform based on Apollo enables users to provide both functional and structural changes that will appear as 'community annotations' immediately and, pending curatorial review, will be integrated into the official genome annotation.


Assuntos
Kinetoplastida , Software , Interface Usuário-Computador , Proteômica , Genômica/métodos , Biologia Computacional/métodos , Bases de Dados Genéticas , Internet
5.
Microbiol Spectr ; 10(6): e0265822, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36342284

RESUMO

Leishmaniasis, a category I neglected tropical disease, is a group of diseases caused by the protozoan parasite Leishmania species with a wide range of clinical manifestations. Current treatment options can be highly toxic and expensive, with drug relapse and the emergence of resistance. Bacteriocins, antimicrobial peptides ribosomally produced by bacteria, are a relatively new avenue for potential antiprotozoal drugs. Particular interest has been focused on enterocin AS-48, with previously proven efficacy against protozoan species, including Leishmania spp. Sequential characterization of enterocin AS-48 has illustrated that antibacterial bioactivity is preserved in linearized, truncated forms; however, minimal domains of AS-48 bacteriocins have not yet been explored against protozoans. Using rational design techniques to improve membrane penetration activity, we designed peptide libraries using the minimal bioactive domain of AS-48 homologs. Stepwise changes to the charge (z), hydrophobicity (H), and hydrophobic dipole moment (µH) were achieved through lysine and tryptophan substitutions and the inversion of residues within the helical wheel, respectively. A total of 480 synthetic peptide variants were assessed for antileishmanial activity against Leishmania donovani. One hundred seventy-two peptide variants exhibited 50% inhibitory concentration (IC50) values below 20 µM against axenic amastigotes, with 60 peptide variants in the nanomolar range. Nine peptide variants exhibited potent activity against intracellular amastigotes with observed IC50 values of <4 µM and limited in vitro host cell toxicity, making them worthy of further drug development. Our work demonstrates that minimal bioactive domains of naturally existing bacteriocins can be synthetically engineered to increase membrane penetration against Leishmania spp. with minimal host cytotoxicity, holding the promise of novel, potent antileishmanial therapies. IMPORTANCE Leishmaniasis is a neglected tropical disease caused by protozoan parasites of the genus Leishmania. There are three primary clinical forms, cutaneous, mucocutaneous, and visceral, with visceral leishmaniasis being fatal if left untreated. Current drug treatments are less than ideal, especially in resource-limited areas, due to the difficult administration and treatment regimens as well as the high cost and the emergence of drug resistance. Identifying potent antileishmanial agents is of the utmost importance. We utilized rational design techniques to synthesize enterocin AS-48 and AS-48-like bacteriocin-based peptides and screened these peptides against L. donovani using a fluorescence-based phenotypic assay. Our results suggest that bacteriocins, specifically these rationally designed AS-48-like peptides, are promising leads for further development as antileishmanial drugs.


Assuntos
Antiprotozoários , Bacteriocinas , Leishmania donovani , Leishmaniose , Humanos , Bacteriocinas/farmacologia , Bacteriocinas/uso terapêutico , Leishmaniose/tratamento farmacológico , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Antiprotozoários/farmacologia
6.
Pest Manag Sci ; 78(7): 2792-2805, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35411662

RESUMO

BACKGROUND: Leishmaniasis is an infectious parasitic disease caused by pathogens of the genus Leishmania transmitted through the bite of adult female sand flies. To reduce case numbers, it is necessary to combine different control approaches, especially those aimed at the sand fly vectors. Innovative forms of control with the use of attractive sugar baits explored the fact that adult sand flies need to feed on sugars of plant origin. Leishmania parasites develop in the gut of sand flies, interacting with the sugars in the diet of adults. Recent studies have shown that sugar baits containing plant-derived compounds can reduce sand fly survival, the number of parasites per gut, and the percentage of infected sand flies. Several synthetic compounds produced from naphthoquinones and pterocarpans have anti-parasitic activity on Leishmania amazonensis and/or Leishmania infantum in cell culture. This work aimed to assess the inclusion of these compounds in sugar baits for blocking transmission, targeting the development of the Leishmania parasite inside the sand fly vector. RESULTS: We evaluated the attractant or repellent properties of these compounds, as well as of the reference compound N,N'-diethyl-m-toluamide (DEET), in sugar baits. We also observed changes in feeding preference caused by these compounds, looking for anti-feeding or stimulation of ingestion. Pterocarpanquinone L4 and pentamidine showed attractant and repellent properties, respectively. CONCLUSION: Based on the effects in feeding preference and intake volume, pterocarpanquinone L6, and the pyrazole-derived compound P8 were chosen as the most promising compounds for the future development of anti-Leishmania sugar baits. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Repelentes de Insetos , Leishmania infantum , Leishmaniose , Phlebotomus , Psychodidae , Animais , Feminino , Leishmania infantum/fisiologia , Leishmaniose/prevenção & controle , Psychodidae/parasitologia , Psychodidae/fisiologia , Açúcares
7.
Nucleic Acids Res ; 50(D1): D898-D911, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718728

RESUMO

The Eukaryotic Pathogen, Vector and Host Informatics Resource (VEuPathDB, https://veupathdb.org) represents the 2019 merger of VectorBase with the EuPathDB projects. As a Bioinformatics Resource Center funded by the National Institutes of Health, with additional support from the Welllcome Trust, VEuPathDB supports >500 organisms comprising invertebrate vectors, eukaryotic pathogens (protists and fungi) and relevant free-living or non-pathogenic species or hosts. Designed to empower researchers with access to Omics data and bioinformatic analyses, VEuPathDB projects integrate >1700 pre-analysed datasets (and associated metadata) with advanced search capabilities, visualizations, and analysis tools in a graphic interface. Diverse data types are analysed with standardized workflows including an in-house OrthoMCL algorithm for predicting orthology. Comparisons are easily made across datasets, data types and organisms in this unique data mining platform. A new site-wide search facilitates access for both experienced and novice users. Upgraded infrastructure and workflows support numerous updates to the web interface, tools, searches and strategies, and Galaxy workspace where users can privately analyse their own data. Forthcoming upgrades include cloud-ready application architecture, expanded support for the Galaxy workspace, tools for interrogating host-pathogen interactions, and improved interactions with affiliated databases (ClinEpiDB, MicrobiomeDB) and other scientific resources, and increased interoperability with the Bacterial & Viral BRC.


Assuntos
Bases de Dados Factuais , Vetores de Doenças/classificação , Interações Hospedeiro-Patógeno/genética , Fenótipo , Interface Usuário-Computador , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/patogenicidade , Bactérias/classificação , Bactérias/genética , Bactérias/patogenicidade , Doenças Transmissíveis/microbiologia , Doenças Transmissíveis/parasitologia , Doenças Transmissíveis/patologia , Doenças Transmissíveis/transmissão , Biologia Computacional/métodos , Mineração de Dados/métodos , Diplomonadida/classificação , Diplomonadida/genética , Diplomonadida/patogenicidade , Fungos/classificação , Fungos/genética , Fungos/patogenicidade , Humanos , Insetos/classificação , Insetos/genética , Insetos/patogenicidade , Internet , Nematoides/classificação , Nematoides/genética , Nematoides/patogenicidade , Filogenia , Virulência , Fluxo de Trabalho
8.
Curr Opin Insect Sci ; 50: 100860, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34864248

RESUMO

VectorBase (VectorBase.org) is part of the VEuPathDB Bioinformatics Resource Center, providing free online access to multi-omics and population biology data, focusing on arthropod vectors and invertebrates of importance to human health. VectorBase includes genomics and functional genomics data from bed bugs, biting midges, body lice, kissing bugs, mites, mosquitoes, sand flies, ticks, tsetse flies, stable flies, house flies, fruit flies, and a snail intermediate host. Tools include the Search Strategy system and MapVEu, enabling users to interrogate and visualize diverse 'omics and population-level data using a graphical interface (no programming experience required). Users can also analyze their own private data, such as transcriptomic sequences, exploring their results in the context of other publicly-available information in the database. Help Desk: help@vectorbase.org.


Assuntos
Biologia Computacional , Culicidae , Animais , Genômica , Humanos , Invertebrados/genética , Mosquitos Vetores
9.
Exp Parasitol ; 220: 107968, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32781093

RESUMO

The parasitic protozoan Leishmania infantum resides primarily in macrophages throughout mammalian infection. Infection is initiated by deposition of the metacyclic promastigote into the dermis of a mammalian host by the sand fly vector. Promastigotes enter macrophages by ligating surface receptors such as complement receptor 3 (CR3), inducing phagocytosis of the parasite. At the binding site of metacyclic promastigotes, we observed large asymmetrical aggregates of macrophage membrane with underlying actin, resembling membrane ruffles. Actin accumulation was observed at the point of initial contact, before phagosome formation and accumulation of peri-phagosomal actin. Ruffle-like structures did not form during phagocytosis of attenuated promastigotes or during phagocytosis of the intracellular amastigote form of L. infantum. Entry of promastigotes through massive actin accumulation was associated with a subsequent delay in fusion of the parasitophorous vacuole (PV) with the lysosomal markers LAMP-1 and Cathepsin D. Actin accumulation was also associated with entry through CR3, since macrophages from CD11b knockout (KO) mice did not form massive aggregates of actin during phagocytosis of metacyclic promastigotes. Furthermore, intracellular survival of L. infantum was significantly decreased in CD11b KO compared to wild type macrophages, although entry rates were similar. We conclude that both promastigote virulence and host cell CR3 are needed for the formation of ruffle-like membrane structures at the site of metacyclic promastigote phagocytosis, and that formation of actin-rich aggregates during entry correlates with the intracellular survival of virulent promastigotes.


Assuntos
Actinas/metabolismo , Leishmania infantum/fisiologia , Leishmaniose Visceral/parasitologia , Antígeno de Macrófago 1/fisiologia , Fagocitose/fisiologia , Animais , Catepsina D/metabolismo , Membrana Celular/ultraestrutura , Cricetinae , Humanos , Leishmania infantum/patogenicidade , Leishmania infantum/ultraestrutura , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Macrófagos/parasitologia , Masculino , Mesocricetus , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Confocal , Vacúolos/parasitologia , Virulência
10.
PLoS Negl Trop Dis ; 14(12): e0008967, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33370303

RESUMO

Phlebotomine sand flies employ an elaborate system of pheromone communication wherein males produce pheromones that attract other males to leks (thus acting as an aggregation pheromone) and females to the lekking males (sex pheromone). In addition, the type of pheromone produced varies among populations. Despite the numerous studies on sand fly chemical communication, little is known of their chemosensory genome. Chemoreceptors interact with chemicals in an organism's environment to elicit essential behaviors such as the identification of suitable mates and food sources. Thus, they play important roles during adaptation and speciation. Major chemoreceptor gene families, odorant receptors (ORs), gustatory receptors (GRs) and ionotropic receptors (IRs) together detect and discriminate the chemical landscape. Here, we annotated the chemoreceptor repertoire in the genomes of Lutzomyia longipalpis and Phlebotomus papatasi, major phlebotomine vectors in the New World and Old World, respectively. Comparison with other sequenced Diptera revealed a large and unique expansion where over 80% of the ~140 ORs belong to a single, taxonomically restricted clade. We next conducted a comprehensive analysis of the chemoreceptors in 63 L. longipalpis individuals from four different locations in Brazil representing allopatric and sympatric populations and three sex-aggregation pheromone types (chemotypes). Population structure based on single nucleotide polymorphisms (SNPs) and gene copy number in the chemoreceptors corresponded with their putative chemotypes, and corroborate previous studies that identified multiple populations. Our work provides genomic insights into the underlying behavioral evolution of sexual communication in the L. longipalpis species complex in Brazil, and highlights the importance of accounting for the ongoing speciation in central and South American Lutzomyia that could have important implications for vectorial capacity.


Assuntos
Células Quimiorreceptoras/metabolismo , Proteínas de Insetos/genética , Leishmaniose/prevenção & controle , Leishmaniose/transmissão , Phlebotomus/parasitologia , Atrativos Sexuais/química , Animais , Brasil , Feminino , Insetos Vetores/parasitologia , Leishmania , Masculino , Phlebotomus/genética , Phlebotomus/fisiologia , Polimorfismo de Nucleotídeo Único/genética
11.
PLoS Negl Trop Dis ; 14(7): e0007489, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32658913

RESUMO

Phlebotomus papatasi sand flies inject their hosts with a myriad of pharmacologically active salivary proteins to assist with blood feeding and to modulate host defenses. In addition, salivary proteins can influence cutaneous leishmaniasis disease outcome, highlighting the potential of the salivary components to be used as a vaccine. Variability of vaccine targets in natural populations influences antigen choice for vaccine development. Therefore, the objective of this study was to investigate the variability in the predicted protein sequences of nine of the most abundantly expressed salivary proteins from field populations, testing the hypothesis that salivary proteins appropriate to target for vaccination strategies will be possible. PpSP12, PpSP14, PpSP28, PpSP29, PpSP30, PpSP32, PpSP36, PpSP42, and PpSP44 mature cDNAs from field collected P. papatasi from three distinct ecotopes in the Middle East and North Africa were amplified, sequenced, and in silico translated to assess the predicted amino acid variability. Two of the predicted sequences, PpSP12 and PpSP14, demonstrated low genetic variability across the three geographic isolated sand fly populations, with conserved multiple predicted MHCII epitope binding sites suggestive of their potential application in vaccination approaches. The other seven predicted salivary proteins revealed greater allelic variation across the same sand fly populations, possibly precluding their use as vaccine targets.


Assuntos
Proteínas de Insetos/genética , Insetos Vetores/genética , Phlebotomus/genética , Proteínas e Peptídeos Salivares/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Egito , Humanos , Proteínas de Insetos/imunologia , Insetos Vetores/imunologia , Jordânia , Phlebotomus/imunologia , Proteínas e Peptídeos Salivares/imunologia , Alinhamento de Sequência
12.
Parasit Vectors ; 12(1): 557, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767025

RESUMO

BACKGROUND: Transmission of malaria in the highlands of Ethiopia is poorly understood and usually attributed to importation by mobile populations or local transmission by Anopheles arabiensis. To characterize and identify Anopheles species present in a highland area of northern Ethiopia, adult and larval collections were performed in Gondar town and the neighboring Senbet Debir village (Dembia district, > 2000 meters above sea level, masl), in addition to Bahir Dar town (capital of Amhara region) and Kumer Aftit village (Metema district, < 2000 masl). METHODS: CDC-light traps were used to collect adult mosquitoes and larval collections were performed from rain pools for rearing into adults for species identification. Collections were made September-March 2016-2018. Adult mosquitoes were identified morphologically and a subset of randomly chosen specimens were identified to species by sequencing the ribosomal DNA internal transcribed spacer region 2 (ITS2) and mitochondrial DNA cytochrome c oxidase subunit 1 (cox1). RESULTS: The primary species of Anopheles identified at elevations higher than 2000 masl was An. cinereus, which was confirmed molecularly by ITS2 and cox1 sequencing. Interestingly, two unknown species were also sequenced, in addition to two specimens of An. pretoriensis. The species collected at sites with elevations less than 2000 masl (Bahir Dar town and Kumer Aftit village) was An. arabiensis. Three Plasmodium falciparum-positive specimens were identified molecularly as An. cinereus. CONCLUSIONS: The presence of Plasmodium-positive An. cinereus in areas greater than 2000 masl incriminates this species as a potential vector contributing to non-peak malaria transmission in Ethiopian highland areas.


Assuntos
Anopheles/parasitologia , Malária/transmissão , Mosquitos Vetores/parasitologia , Animais , Etiópia , Feminino , Larva/parasitologia , Malária/prevenção & controle , Plasmodium falciparum , Chuva
13.
Int J Antimicrob Agents ; 54(4): 496-501, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323307

RESUMO

Leishmania parasites are the causative agents of a wide spectrum of human diseases. The clinical manifestations of leishmaniasis range from self-healing skin lesions to fatality. The World Health Organization has classed leishmaniasis as a category 1 neglected tropical disease. Leishmaniasis represents a major international health challenge, affecting 12 million people per year and with nearly 310 million people at risk. The first-line chemotherapies used to treat leishmaniasis are intravenous pentavalent antimonials; however, these drugs are highly toxic. As the use of oral treatment options such as paromomycin and miltefosine has increased, the incidence of disease relapse has increased and drug resistance to antimonials has developed, emphasizing the importance of identifying new chemotherapies. A novel, target-free fluorometric high-throughput screen with an average Z-score of 0.73 +/- 0.13 has been developed to identify small molecules with antileishmanial activity. Screening of 10,000 small molecules from the ChemBridge DIVER-set™ library cassette #5 yielded 210 compounds that killed 80% of parasites, resulting in a hit rate of 2.1%. One hundred and nine molecular scaffolds were represented within the hit compounds, and one scaffold that exhibited potent antileishmanial activity was 2,4-diaminoquinazoline. Host cell toxicity was determined prior to in-vitro infection of human THP-1 macrophages with Leishmania donovani mCherry expressing promastigotes; successful drug treatment was considered when the half maximal inhibitory concentration was <10 µM. BALB/c mice were infected with Leishmania major mCherry promastigotes and treated with small molecules that were successful during in-vitro infections. Several small molecules tested were as efficacious at resolving cutaneous leishmaniasis lesions in mice as known antimonial treatments.


Assuntos
Antiprotozoários/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala , Leishmania donovani/efeitos dos fármacos , Leishmania major/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Animais , Antiprotozoários/administração & dosagem , Antiprotozoários/farmacologia , Modelos Animais de Doenças , Feminino , Fluorometria/métodos , Humanos , Camundongos Endogâmicos BALB C , Recidiva , Células THP-1/parasitologia , Resultado do Tratamento
14.
Sci Rep ; 9(1): 4421, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-30872615

RESUMO

Aedes aegypti and Anopheles gambiae harbor the causative agents of diseases such as dengue fever and malaria, afflicting human morbidity and mortality worldwide. Given the worldwide emergence of resistance to insecticides, the current mainstay for vector control, identification of alternative modes of action for future insecticides is paramount. The serotonergic (5-HT) system has been documented to impact physiological mechanisms involved in disease transmission, suggesting its potential as a new mode of action target for future insecticide development. Target 5-HT receptors were cloned and expressed in the HEK293 cell line for functional and pharmacological characterization. Manipulation of the 5-HT system through microinjection of compounds suggests its involvement in the modulation of flight performance and blood-feeding behavior. By attenuating these two determinants of vectorial capacity, transmission and burden of disease could effectively be reduced. Considering these positive global health implications, the 5-HT system is a compelling target for the novel insecticide pipeline.


Assuntos
Aedes/metabolismo , Anopheles/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Voo Animal/efeitos dos fármacos , Inseticidas/farmacologia , Mosquitos Vetores/metabolismo , Receptores de Serotonina/metabolismo , Aedes/efeitos dos fármacos , Aedes/parasitologia , Animais , Anopheles/efeitos dos fármacos , Anopheles/parasitologia , Feminino , Resistência a Inseticidas , Malária/tratamento farmacológico , Malária/metabolismo , Malária/parasitologia , Mosquitos Vetores/efeitos dos fármacos , Mosquitos Vetores/parasitologia , Plasmodium malariae/isolamento & purificação , Receptores de Serotonina/genética
15.
Parasit Vectors ; 11(1): 160, 2018 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-29523212

RESUMO

BACKGROUND: Phlebotomus papatasi is a widely distributed sand fly species in different tropical and sub-tropical regions including the Middle East and North Africa. It is considered an important vector that transmits Leishmania major parasites, the causative agents of cutaneous leishmaniasis. The development of microsatellite markers for this sand fly vector is of high interest to understand its population structure and to monitor its geographic dispersal. RESULTS: Fourteen polymorphic microsatellite markers were developed with simple di-, tri- and tetra-nucleotide repeats. The F statistics calculated for the 14 markers revealed high genetic diversity; expected heterozygosity (He) ranged from 0.407 to 0.767, while observed heterozygosity (Ho) was lower and ranged from 0.083 to 0.514. The number of alleles sampled fall in the range of 9-29. Three out of 14 markers deviated from Hardy-Weinberg expectations, no significant linkage disequilibrium was detected and high values for inbreeding coefficient (FIS) were likely due to inbreeding. CONCLUSIONS: The development of these functional microsatellites enable a high resolution of P. papatasi populations. It opens a path for researchers to perform multi locus-based population genetic structure analyses, and comparative mapping, a part of the efforts to uncover the population dynamics of this vector, which is an important global strategy for understanding the epidemiology and control of leishmaniasis.


Assuntos
Distribuição Animal , Etiquetas de Sequências Expressas , Insetos Vetores/classificação , Insetos Vetores/crescimento & desenvolvimento , Repetições de Microssatélites , Phlebotomus/classificação , Phlebotomus/crescimento & desenvolvimento , África do Norte , Alelos , Animais , Variação Genética , Genótipo , Heterozigoto , Insetos Vetores/genética , Oriente Médio , Phlebotomus/genética
16.
Parasit Vectors ; 11(1): 214, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29587873

RESUMO

BACKGROUND: Phlebotomus papatasi sand flies are major vectors of Leishmania major and phlebovirus infection in North Africa and across the Middle East to the Indian subcontinent. Population genetics is a valuable tool in understanding the level of genetic variability present in vector populations, vector competence, and the development of novel control strategies. This study investigated the genetic differentiation between P. papatasi populations in Egypt and Jordan that inhabit distinct ecotopes and compared this structure to P. papatasi populations from a broader geographical range. METHODS: A 461 base pair (bp) fragment from the mtDNA cytochrome b (cyt b) gene was PCR amplified and sequenced from 116 individual female sand flies from Aswan and North Sinai, Egypt, as well as Swaimeh and Malka, Jordan. Haplotypes were identified and used to generate a median-joining network, F ST values and isolation-by-distance were also evaluated. Additional sand fly individuals from Afghanistan, Iran, Israel, Jordan, Libya, Tunisia and Turkey were included as well as previously published haplotypes to provide a geographically broad genetic variation analysis. RESULTS: Thirteen haplotypes displaying nine variant sites were identified from P. papatasi collected in Egypt and Jordan. No private haplotypes were identified from samples in North Sinai, Egypt, two were observed in Aswan, Egypt, four from Swaimeh, Jordan and two in Malka, Jordan. The Jordan populations clustered separately from the Egypt populations and produced more private haplotypes than those from Egypt. Pairwise F ST values fall in the range 0.024-0.648. CONCLUSION: The clustering patterns and pairwise F ST values indicate a strong differentiation between Egyptian and Jordanian populations, although this population structure is not due to isolation-by-distance. Other factors, such as environmental influences and the genetic variability in the circulating Le. major parasites, could possibly contribute to this heterogeneity. The present study aligns with previous reports in that pockets of genetic differentiation exists between populations of this widely dispersed species but, overall, the species remains relatively homogeneous.


Assuntos
Citocromos b/genética , Variação Genética , Genética Populacional , Haplótipos , Phlebotomus/classificação , Phlebotomus/crescimento & desenvolvimento , Filogeografia , Animais , Egito , Insetos Vetores/classificação , Insetos Vetores/genética , Insetos Vetores/crescimento & desenvolvimento , Jordânia , Phlebotomus/genética
17.
Mem Inst Oswaldo Cruz ; 112(1): 1-7, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28076467

RESUMO

Insects are considered pests globally, implicated in the destruction of agricultural fields and transmission of pathogens that cause deadly human diseases, such as dengue, Zika and malaria. The diversity of the insecticide arsenal has remained stagnant for decades, but the recent rise of insecticide resistance fueled the discovery of novel modes of action, and the power of genomics has reinvigorated this search. This review discusses the importance of comparative and functional insect genomics in the identification of potential gene targets for an insecticidal mode of action with low off-target toxicity. Due to the global participation in the sequencing and annotation of insect genomes, the targeting of specific genes with molecular tools like RNAi and CRISPR/Cas9 for genome engineering and consequent functional identification and validation has become more efficient. While there are multiple avenues to explore for insecticidal candidates, this review identifies G-protein coupled receptors as attractive targets, and hones in on the octopamine and dopamine receptors due to their potential.


Assuntos
Marcação de Genes/métodos , Genoma de Inseto , Insetos , Inseticidas , Receptores Acoplados a Proteínas G/genética , Animais , Controle de Insetos/métodos , Resistência a Inseticidas/genética , Interferência de RNA/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo
18.
Mem. Inst. Oswaldo Cruz ; 112(1): 1-7, Jan. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-841758

RESUMO

Insects are considered pests globally, implicated in the destruction of agricultural fields and transmission of pathogens that cause deadly human diseases, such as dengue, Zika and malaria. The diversity of the insecticide arsenal has remained stagnant for decades, but the recent rise of insecticide resistance fueled the discovery of novel modes of action, and the power of genomics has reinvigorated this search. This review discusses the importance of comparative and functional insect genomics in the identification of potential gene targets for an insecticidal mode of action with low off-target toxicity. Due to the global participation in the sequencing and annotation of insect genomes, the targeting of specific genes with molecular tools like RNAi and CRISPR/Cas9 for genome engineering and consequent functional identification and validation has become more efficient. While there are multiple avenues to explore for insecticidal candidates, this review identifies G-protein coupled receptors as attractive targets, and hones in on the octopamine and dopamine receptors due to their potential.


Assuntos
Animais , Marcação de Genes/métodos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Resistência a Inseticidas , Controle de Insetos/métodos , Interferência de RNA , Genoma de Inseto , Inseticidas
19.
Parasitol Res ; 115(9): 3345-55, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27160331

RESUMO

Phlebotomine sand flies are the known vectors of Leishmania parasites. New approaches in vaccination against Leishmania have investigated the possibility of integrating Phlebotomus papatasi salivary proteins to enhance the immune response and protect against the transmission of the infection. The aim of the present study was to screen human immune responses to wild sand fly saliva and evaluate immunogenic salivary proteins. Blood samples were collected from donors in control and sand fly infested areas. Antibodies specific for sand fly antigens in donor plasma were probed using immunoblotting. In addition, recall proliferation capability of peripheral blood mononuclear cells (PBMC) was tested after sand fly salivary homogenates stimulation. The significant immunogenic salivary proteins (SPs) identified by immunoblotting were SP28, SP32, and SP36. A specific proliferative response of PBMC after stimulation with sand fly salivary homogenates was evident in donors that have antibody responses against sand fly salivary proteins. Individuals with antibody recognition to a higher number of salivary proteins (i.e., 3 or more SP bands) showed lower PBMC proliferative responses after in vitro stimulation with salivary gland homogenates (SGH) only in the sand fly infested, leishmaniasis free area. Interestingly, the presence of a humoral immune response to many SP antigens inversely correlates with a strong cell-mediated immune response (CMI). It was also noticed that some other heavily expressed antigens, in sand fly salivary homogenate, lack or have weak humoral immune reactivity in exposed individuals. Therefore, considering these antigens alone as CMI activators, without including the immunodominant humoral immune response proteins, needs future investigation.


Assuntos
Formação de Anticorpos , Proteínas de Insetos/imunologia , Leishmaniose/imunologia , Phlebotomus/imunologia , Proteínas e Peptídeos Salivares/imunologia , Adulto , Animais , Feminino , Humanos , Proteínas de Insetos/genética , Leishmania/imunologia , Leishmaniose/parasitologia , Leishmaniose/prevenção & controle , Leishmaniose/transmissão , Leucócitos Mononucleares/imunologia , Masculino , Phlebotomus/genética , Phlebotomus/parasitologia , Proteínas e Peptídeos Salivares/genética , Vacinas/genética , Vacinas/imunologia , Adulto Jovem
20.
J Leukoc Biol ; 100(4): 665-677, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27084569

RESUMO

Ablation of microRNA synthesis by deletion of the microRNA-processing enzyme Dicer has demonstrated that microRNAs are necessary for normal hematopoietic differentiation and function. However, it is still unclear which specific microRNAs are required for hematopoiesis and at what developmental stages they are necessary. This is especially true for immune cell development. We previously observed that overexpression of the products of the mirn23a gene (microRNA-23a, -24-2, and 27a) in hematopoietic progenitors increased myelopoiesis with a reciprocal decrease in B lymphopoiesis, both in vivo and in vitro. In this study, we generated a microRNA-23a, -24-2, and 27a germline knockout mouse to determine whether microRNA-23a, -24-2, and 27a expression was essential for immune cell development. Characterization of hematopoiesis in microRNA-23a, -24-2, and 27a-/- mice revealed a significant increase in B lymphocytes in both the bone marrow and the spleen, with a concomitant decrease in myeloid cells (monocytes/granulocytes). Analysis of the bone marrow progenitor populations revealed a significant increase in common lymphoid progenitors and a significant decrease in both bone marrow common myeloid progenitors and granulocyte monocyte progenitors. Gene-expression analysis of primary hematopoietic progenitors and multipotent erythroid myeloid lymphoid cells showed that microRNA-23a, -24-2, and 27a regulates essential B cell gene-expression networks. Overexpression of microRNA-24-2 target Tribbles homolog 3 can recapitulate the microRNA-23a, -24-2, and 27a-/- phenotype in vitro, suggesting that increased B cell development in microRNA-23a, -24-2, and 27a null mice can be partially explained by a Tribbles homolog 3-dependent mechanism. Data from microRNA-23a, -24-2, and 27a-/- mice support a critical role for this microRNA cluster in regulating immune cell populations through repression of B lymphopoiesis.


Assuntos
Linfócitos B/patologia , Linfopoese/fisiologia , MicroRNAs/fisiologia , Animais , Antígenos de Diferenciação de Linfócitos B/análise , Células da Medula Óssea/patologia , Proteínas de Ciclo Celular/fisiologia , Linhagem Celular , Redes Reguladoras de Genes , Imunoglobulina G/biossíntese , Ativação Linfocitária , Contagem de Linfócitos , Linfopoese/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , MicroRNAs/genética , Células Mieloides/patologia , Plasmócitos/imunologia
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