arthropod vector
Dotaz
Zobrazit nápovědu
The olfactory response of insect vectors such as phlebotomine sand flies is a key facet for investigating their interactions with vertebrate hosts and associated vector-borne pathogens. Such studies are mainly performed by assessing the electrophysiological response and the olfactory behaviour of these arthropods towards volatile organic compounds (VOCs) produced by hosts. Nonetheless, few studies are available for species of the subgenera Lutzomyia and Nyssomyia in South America, leaving a void for Old World sand fly species of the genus Phlebotomus. In this study, we evaluated the olfactory responses of Phlebotomus perniciosus, one of the most important vectors of Leishmania infantum in the Old World. To test the P. perniciosus behavioural response to VOCs, 28 compounds isolated from humans and dogs were assessed using electrophysiological (i.e., electroantennogram, EAG) and behavioural assays (i.e., Y-tube olfactometer). In the EAG trials, 14 compounds (i.e., acetic acid, nonanoic acid, 2-propanol, 2-butanol, pentanal, hexanal, nonanal, trans-2-nonenal, decanal, myrcene, p-cymene, verbenone, 2-ethyl-1-hexanol, and acetonitrile) elicited high antennal responses (i.e., ≥ 0.30 mV) in female sand flies, being those VOCs selected for the behavioural assays. From the 14 compounds tested in the Y-tube olfactometer, nonanal was significantly attractive for P. perniciosus females, whereas myrcene and p-cymene were significantly repellents (p < 0.05). The attraction indexes varied from 0.53 for nonanal (i.e., most attractive) to -0.47 to p-cymene (i.e., most repellent). Overall, our results shed light on the role of olfactory cues routing host seeking behaviour in P. perniciosus, with implications to develop sustainable sand fly monitoring as well as control in leishmaniasis endemic areas.
- MeSH
- chování zvířat účinky léků MeSH
- hmyz - vektory fyziologie účinky léků MeSH
- Leishmania infantum účinky léků fyziologie MeSH
- lidé MeSH
- Phlebotomus * fyziologie účinky léků MeSH
- psi MeSH
- těkavé organické sloučeniny * farmakologie chemie analýza MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- psi MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Tularemie je zoonóza, jejíž původcem je Francisella tularensis, gramnegativní aerobní bakterie patřící do třídy Gammaproteobacteria a čeledi Francisellaceae. Navzdory skutečnosti, že F. tularensis může mít významný dopad na zdraví člověka, existuje o aktuálním výskytu tohoto patogenu v různých hematofágních členovcích pouze velmi málo údajů. Cílem studie bylo provést rozsáhlý molekulární screening různých potenciálních hematofágních vektorů: klíšťat (4348 jedinců druhů Ixodes ricinus, Dermacentor reticulatus a Haemaphysalis concinna), komárů (4100 jedinců druhu Aedes vexans) a muchniček (6900 jedinců Simulium spp.) na přítomnost F. tularensis na Břeclavsku v roce 2022. Pozitivní byly pouze 2 vzorky, které obsahovaly DNA specifickou pro F. tularensis subsp. holarctica. Oba vzorky pocházely z klíštěte D. reticulatus a to jak po infestaci srnce, tak jednoho směsného vzorku nasbíraných klíšťat (n = 10). Oba pozitivní vzorky byly sekvenovány a byla potvrzena přítomnost F. tularensis subsp. holarctica. Přítomnost
Tularemia is a zoonosis caused by Francisella tularensis, a gram-negative aerobic bacterium belonging to the class of Gammaproteobacteria and the family Francisellaceae. Despite its undeniable importance for human health, there is little data on the current distribution of F. tularensis in various hematophagous arthropods. The aim of this study was to perform a mass molecular screening of different possible hematophagous vectors: ticks (4348 ticks of the species Ixodes ricinus, Dermacentor reticulatus, and Haemaphysalis concinna), mosquitoes (4100 specimens of Aedes vexans), and blackflies (6900 specimens of the Simulium spp.) for the presence of F. tularensis in the Břeclav district in 2022. Only two specimens were positive for the specific DNA of Francisella tularensis subsp. holarctica. Both samples originated from D. reticulatus, one collected from infested roe deer and the other included in a pooled sample (n = 10). Both positive samples were sequenced, and the presence of F. tularensis subsp. holarctica was confirmed. In addition, the absence of F. tularensis in mosquitoes and black flies was documented.
- MeSH
- Francisella tularensis * patogenita MeSH
- genetické techniky MeSH
- infekce přenášené vektorem * MeSH
- komáří přenašeči mikrobiologie MeSH
- kontrola infekčních nemocí * metody MeSH
- lidé MeSH
- nemoci přenášené klíšťaty epidemiologie mikrobiologie přenos MeSH
- Simuliidae mikrobiologie MeSH
- tularemie epidemiologie mikrobiologie přenos MeSH
- zdroje nemoci mikrobiologie MeSH
- Check Tag
- lidé MeSH
- Geografické názvy
- Česká republika MeSH
Bartonelloses are neglected emerging infectious diseases caused by facultatively intracellular bacteria transmitted between vertebrate hosts by various arthropod vectors. The highest diversity of Bartonella species has been identified in rodents. Within this study we focused on the edible dormouse (Glis glis), a rodent with unique life-history traits that often enters households and whose possible role in the epidemiology of Bartonella infections had been previously unknown. We identified and cultivated two distinct Bartonella sub(species) significantly diverging from previously described species, which were characterized using growth characteristics, biochemical tests, and various molecular techniques including also proteomics. Two novel (sub)species were described: Bartonella grahamii subsp. shimonis subsp. nov. and Bartonella gliris sp. nov. We sequenced two individual strains per each described (sub)species. During exploratory genomic analyses comparing two genotypes ultimately belonging to the same species, both factually and most importantly even spatiotemporally, we noticed unexpectedly significant structural variation between them. We found that most of the detected structural variants could be explained either by prophage excision or integration. Based on a detailed study of one such event, we argue that prophage deletion represents the most probable explanation of the observed phenomena. Moreover, in one strain of Bartonella grahamii subsp. shimonis subsp. nov. we identified a deletion related to Bartonella Adhesin A, a major pathogenicity factor that modulates bacteria-host interactions. Altogether, our results suggest that even a limited number of passages induced sufficient selective pressure to promote significant changes at the level of the genome.
- Publikační typ
- časopisecké články MeSH
With the current expansion of vector-based research and an increasing number of facilities rearing arthropod vectors and infecting them with pathogens, common measures for containment of arthropods as well as manipulation of pathogens are becoming essential for the design and running of such research facilities to ensure safe work and reproducibility, without compromising experimental feasibility. These guidelines and comments were written by experts of the Infravec2 consortium, a Horizon 2020-funded consortium integrating the most sophisticated European infrastructures for research on arthropod vectors of human and animal diseases. They reflect current good practice across European laboratories with experience of safely handling different mosquito species and the pathogens they transmit. As such, they provide experience-based advice to assess and manage the risks to work safely with mosquitoes and the pathogens they transmit. This document can also form the basis for research with other arthropods, for example, midges, ticks or sandflies, with some modification to reflect specific requirements.
- MeSH
- členovci - vektory MeSH
- členovci * MeSH
- Culicidae * MeSH
- komáří přenašeči MeSH
- lidé MeSH
- reprodukovatelnost výsledků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Evropa MeSH
Sand flies (Diptera: Phlebotominae) are proven vectors of various pathogens of medical and veterinary importance. Although mostly known for their pivotal role in the transmission of parasitic protists of the genus Leishmania that cause leishmaniases, they are also proven or suspected vectors of many arboviruses, some of which threaten human and animal health, causing disorders such as human encephalitis (Chandipura virus) or serious diseases of domestic animals (vesicular stomatitis viruses). We reviewed the literature to summarize the current published information on viruses detected in or isolated from phlebotomine sand flies, excluding the family Phenuiviridae with the genus Phlebovirus, as these have been well investigated and up-to-date reviews are available. Sand fly-borne viruses from four other families (Rhabdoviridae, Flaviviridae, Reoviridae and Peribunyaviridae) and one unclassified group (Negevirus) are reviewed for the first time regarding their distribution in nature, host and vector specificity, and potential natural transmission cycles.
- MeSH
- arboviry * MeSH
- hospodářská zvířata MeSH
- lidé MeSH
- Phlebovirus * MeSH
- Psychodidae * MeSH
- Rhabdoviridae * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
BACKGROUND: Salivary glands from blood-feeding arthropods secrete several molecules that inhibit mammalian hemostasis and facilitate blood feeding and pathogen transmission. The salivary functions from Simulium guianense, the main vector of Onchocerciasis in South America, remain largely understudied. Here, we have characterized a salivary protease inhibitor (Guianensin) from the blackfly Simulium guianense. MATERIALS AND METHODS: A combination of bioinformatic and biophysical analyses, recombinant protein production, in vitro and in vivo experiments were utilized to characterize the molecula mechanism of action of Guianensin. Kinetics of Guianensin interaction with proteases involved in vertebrate inflammation and coagulation were carried out by surface plasmon resonance and isothermal titration calorimetry. Plasma recalcification and coagulometry and tail bleeding assays were performed to understand the role of Guianensin in coagulation. RESULTS: Guianensin was identified in the sialotranscriptome of adult S. guianense flies and belongs to the Kunitz domain of protease inhibitors. It targets various serine proteases involved in hemostasis and inflammation. Binding to these enzymes is highly specific to the catalytic site and is not detectable for their zymogens, the catalytic site-blocked human coagulation factor Xa (FXa), or thrombin. Accordingly, Guianensin significantly increased both PT (Prothrombin time) and aPTT (Activated partial thromboplastin time) in human plasma and consequently increased blood clotting time ex vivo. Guianensin also inhibited prothrombinase activity on endothelial cells. We show that Guianensin acts as a potent anti-inflammatory molecule on FXa-induced paw edema formation in mice. CONCLUSION: The information generated by this work highlights the biological functionality of Guianensin as an antithrombotic and anti-inflammatory protein that may play significant roles in blood feeding and pathogen transmission.
- MeSH
- antiflogistika farmakologie MeSH
- endoteliální buňky MeSH
- hemostatika * MeSH
- hemostáza MeSH
- lidé MeSH
- myši MeSH
- savci MeSH
- Simuliidae * MeSH
- slinné proteiny a peptidy farmakologie MeSH
- zánět MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Research Support, N.I.H., Intramural MeSH
Compounds isolated from botanical sources represent innovative and promising alternatives to conventional insecticides. Carlina oxide is a compound isolated from Carlina acaulis L. (Asteraceae) essential oil (EO) with great potential as bioinsecticide, being effective on various arthropod vectors and agricultural pests, with moderate toxicity on non-target species. Since the production from the wild source is limited, there is the need of exploring new synthetic routes for obtaining this compound and analogues with improved bioactivity and lower toxicity. Herein, the chemical synthesis of carlina oxide analogues was developed. Their insecticidal activity was assessed on the vectors Musca domestica L. and Culex quinquefasciatus Say, and their cytotoxicity was evaluated on a human keratinocyte cell line (HaCaT). The compounds' activity was compared with that of the natural counterparts EO and carlina oxide. In housefly tests, the analogues were comparably effective to purified carlina oxide. In Cx. quinquefasciatus assays, the meta-chloro analogue provided a significantly higher efficacy (LC50 of 0.71 μg mL-1) than the EO and carlina oxide (LC50 1.21 and 1.31 μg mL-1, respectively) and a better safety profile than carlina oxide on keratinocytes. Overall, this study can open the way to an agrochemical production of carlina oxide analogues employable as nature-inspired insecticides.
- MeSH
- Asteraceae * chemie MeSH
- Culex * MeSH
- insekticidy * farmakologie MeSH
- komáří přenašeči MeSH
- larva MeSH
- lidé MeSH
- oleje prchavé * farmakologie chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Toscana virus (TOSV) (Bunyavirales, Phenuiviridae, Phlebovirus, Toscana phlebovirus) and other related human pathogenic arboviruses are transmitted by phlebotomine sand flies. TOSV has been reported in nations bordering the Mediterranean Sea among other regions. Infection can result in febrile illness as well as meningitis and encephalitis. Understanding vector-arbovirus interactions is crucial to improving our knowledge of how arboviruses spread, and in this context, immune responses that control viral replication play a significant role. Extensive research has been conducted on mosquito vector immunity against arboviruses, with RNA interference (RNAi) and specifically the exogenous siRNA (exo-siRNA) pathway playing a critical role. However, the antiviral immunity of phlebotomine sand flies is less well understood. Here we were able to show that the exo-siRNA pathway is active in a Phlebotomus papatasi-derived cell line. Following TOSV infection, distinctive 21 nucleotide virus-derived small interfering RNAs (vsiRNAs) were detected. We also identified the exo-siRNA effector Ago2 in this cell line, and silencing its expression rendered the exo-siRNA pathway largely inactive. Thus, our data show that this pathway is active as an antiviral response against a sand fly transmitted bunyavirus, TOSV.
- MeSH
- arboviry * genetika MeSH
- lidé MeSH
- malá interferující RNA genetika MeSH
- Phlebotomus * genetika MeSH
- Phlebovirus * genetika MeSH
- Psychodidae * genetika MeSH
- RNA interference MeSH
- virus horečky pappataci * genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
INTRODUCTION: Borrelia burgdorferi sensu lato, the causative agents of Lyme borreliosis, are transmitted by Ixodes ticks. Tick saliva proteins are instrumental for survival of both the vector and spirochete and have been investigated as targets for vaccine targeting the vector. In Europe, the main vector for Lyme borreliosis is Ixodes ricinus, which predominantly transmits Borrelia afzelii. We here investigated the differential production of I. ricinus tick saliva proteins in response to feeding and B. afzelii infection. METHOD: Label-free Quantitative Proteomics and Progenesis QI software was used to identify, compare, and select tick salivary gland proteins differentially produced during tick feeding and in response to B. afzelii infection. Tick saliva proteins were selected for validation, recombinantly expressed and used in both mouse and guinea pig vaccination and tick-challenge studies. RESULTS: We identified 870 I. ricinus proteins from which 68 were overrepresented upon 24-hours of feeding and B. afzelii infection. Selected tick proteins were successfully validated by confirming their expression at the RNA and native protein level in independent tick pools. When used in a recombinant vaccine formulation, these tick proteins significantly reduced the post-engorgement weights of I. ricinus nymphs in two experimental animal models. Despite the reduced ability of ticks to feed on vaccinated animals, we observed efficient transmission of B. afzelii to the murine host. CONCLUSION: Using quantitative proteomics, we identified differential protein production in I. ricinus salivary glands in response to B. afzelii infection and different feeding conditions. These results provide novel insights into the process of I. ricinus feeding and B. afzelii transmission and revealed novel candidates for an anti-tick vaccine.
- MeSH
- arachnida jako vektory MeSH
- klíště * MeSH
- lymeská nemoc * prevence a kontrola MeSH
- morčata MeSH
- myši MeSH
- proteiny členovců MeSH
- proteom MeSH
- slinné žlázy MeSH
- vakcíny * MeSH
- zvířata MeSH
- Check Tag
- morčata MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Arthropod disease vectors not only transmit malaria but many other serious diseases, many of which are, to a greater or lesser degree, neglected [...].
