Autori desiderano ringraziare Frey John e Ben Peterson per l&#39;allevamento di zanzare. Ringraziamo anche Christine Davis e Gary Radice per un aiuto con micrografie hemocyte. Questa ricerca è stata finanziata dalla University of Richmond Arte e Scienza di borsa di studio estiva AA Qayum e docenti concedere ad A. Telang.

1. Preparazione in anticipo della raccolta hemocyte <ol><li> Preparare una soluzione diluente emolinfa che consiste di 60% di media Schneider, 10% di siero fetale bovino (FBS) e tampone citrato 30% (anticoagulante; 98 mM NaOH, 186 mM NaCl, 1,7 mM EDTA, 41 ml Acido citrico, pH 4,5) 11. Fai aliquote 1,0 ml che possono essere conservati a -20 ° C. Utilizzare ciascuna aliquota solo una volta (vedi Materiali). </li><li> Preparare vetrini da microscopio in vetro (75 x 25 x 1 mm) segnando un 1 cm di diametro cerchio ad una estremità con un vetro incisione strumento. In alternativa, vetrini da microscopio con due pre-inciso circoli possono essere acquistati (ad esempio Fisher Scientific o fonti EMS). Una lastra di vetro per le zanzare saranno necessari. </li><li> Preparare un set di aghi di vetro (vedi Materiali) tirato in base alle seguenti impostazioni suggerite (Sutter Instruments, modello P-87): <table border="1"><tbody><tr><td> Rampa di calore 5 </td></tr><tr><td> Pull: 45 </td></tr><tr><td> Vel: 75 </td></tr><tr><td> Tempo: 175 </td></tr><tr><td> Pressione 580 </td></tr></tbody></table> Utilizzando le impostazioni consigliate su questo estrattore, costruiamo aghi che sono circa 500 mm di lunghezza complessiva con gambo lunghezza di circa 3 mm. Pre-tirato aghi possono anche essere acquistati (ad esempio Tritech Ricerca). </li></ol> 2. Preparazione del microinjector in anticipo della raccolta hemocyte <ol><li> Inserire un ago tirato in porta aghi microinjector secondo le istruzioni del produttore. Backfill il (vedi Materiali) microinjector tubi, siringhe e tirò ago di vetro con olio minerale secondo le istruzioni del produttore. </li></ol> 3. Preparazione di zanzare femmine in anticipo della raccolta hemocyte <ol><li> Aspirare 15 femmine adulte in piccoli contenitori gabbia solido che può essere in contatto con il ghiaccio. Gabbia immergere con le zanzare nel ghiaccio abbastanza profondo in modo che l&#39;intera altezza della gabbia e da tutte le parti sono in contatto con il ghiaccio. Questo farà sì che tutte le zanzare saranno esposti al freddo. Freddo zanzare anestetizzare per circa 8 minuti o fino a quando non sono più mobili. </li><li> Mettere una zanzara in una diapositiva depressione. Questa diapositiva servirà come sito per preparazioni iniettabili. </li></ol> 4. Raccolta Hemocyte <ol><li> Impostare il microinjector a raccogliere 12 ml di diluente emolinfa in ago di vetro tirato e iniettare la soluzione nella zanzara tra i segmenti settima e l&#39;ottava addominale. Circa 3 zanzare possono essere iniettati con 3-3,5 l di totale 12 microlitri di volume occupato. La zanzara deve essere delicatamente tenuta in posizione con una pinza, mentre l&#39;iniezione viene eseguita. Una piccola quantità di diluente deve rimanere alla punta dell&#39;ago in modo da evitare l&#39;olio minerale venga iniettato. Dopo l&#39;iniezione l&#39;addome dovrebbe essere &quot;riempita&quot; o gonfio. </li><li> Luogo iniettato zanzare in un contenitore separato pulito sul ghiaccio per recuperare per 5 min. L&#39;incubazione della soluzione diluente anticoagulante all&#39;interno della zanzara aiuterà sloggiare ematociti concentrati aderendo ai tessuti interni. In media 3-5 zanzare fresca può essere iniettato durante ogni periodo di 5 minuti di recupero. </li><li> Dopo 5 minuti di recupero, snip fuori le gambe, le ali e la punta dell&#39;addome (al segmento ottavo) di ciascuno zanzara in un momento con le forbici micro. Questo dovrebbe essere fatto nella coppa di recupero posti su ghiaccio. Tagliare le gambe e le ali riduce la probabilità di scale di essere trasferito a raccolta diapositive. Nota: non tagliare le gambe e le ali troppo vicino ai siti attaccamento toracica o si rischia di creare altre aperture per emolinfa di scappare. Emolinfa devono essere raccolti attraverso l&#39;apertura creata sulla punta del ventre. </li><li> Lavarsi vetrino da microscopio in vetro inciso con il 70% etanolo e asciugare con un kimwipe. Una posizione iniettato e recuperato zanzara sulla diapositiva sul bordo esterno del cerchio inciso. Impostare microinjector per raccogliere 12 ml di diluente emolinfa fresca e iniettare in questo volume la zanzara nella parte laterale della sua mesotorace. Fornire la maggior parte ma non l&#39;intero volume di diluente (circa 8 - 10 mL) in modo da evitare l&#39;olio minerale venga iniettato. Una piccola quantità di diluente deve rimanere alla punta dell&#39;ago. </li><li> Posizionare la zanzara in modo che l&#39;apertura taglio addominale è al bordo del cerchio di 1 cm. Dopo l&#39;iniezione l&#39;emolinfa diluita deve essere raccolti all&#39;interno dell&#39;area contrassegnata. Una volta che l&#39;ago viene rimosso dal sito di iniezione mesothoracic, riprendere tenendo la zanzara tra i due bracci della pinza e spremere delicatamente l&#39;addome con le pinze per dirigere l&#39;emolinfa sulla zona cerchio inciso. </li><li> Lasciare emolinfa diluita ad asciugare su slitta per circa 10 minuti o fino a quando è visibilmente asciutto. </li></ol> 5. Hemocyte fissazione e colorazione <ol><li> Macchia ogni diapositiva separatamente con HEMA3 7 (vedi Materiali): Dip slide in fissativo 5 volte per 1 secondo ogni volta; Dipslide in soluzione I 3 volte per 1 secondo ciascuna, e, infine, dip scivolare in soluzione II, 3 volte per 1 secondo ciascuna. Lavare la parte posteriore del vetrino con acqua deionizzata. La parte anteriore della slitta non deve essere risciacquato. Blot-asciugare la parte anteriore della slitta fuori cerchio inciso contenenti tessuto colorato. </li><li> Applicare mezzo di montaggio (ad esempio Sur / o Monte Polymount) intorno al centro inciso e mettere un coperchio scivolare su di esso. Premere leggermente sul vetrino (25 x 25 mm) in modo che gli spread medio di montaggio per l&#39;intera area coperta dal vetrino (compresi cerchio inciso contenenti tessuto colorate). Lasciare i vetrini si asciughino per un minimo di 3 ore o durante la notte. Ematociti concentrati deve essere considerato entro 2 settimane dopo la raccolta per la visualizzazione ottimale e di imaging. </li></ol> 6. Rappresentante Risultati Esempi di ematociti concentrati colorati fissi e HEMA3 raccolti da una femmina di Aedes aegypti adulti sono mostrati nella Figura 1A-C. La figura 1A mostra un hemocyte che abbiamo identificato come un prohemocyte in base alla sua piccola dimensione, forma sferica-sferoidale e di alta nucleare rapporto citoplasma (ingrandimento 550X) 11. Figura 1B mostra un hemocyte classificata come oenocytoid in base alla sua forma sferoidale e citoplasma elevato rapporto nucleare (ingrandimento 550X). Infine, la Figura 1C mostra un tipo di granulociti-hemocyte (ingrandimento 550X). Granulociti sono più granulari in natura e tendono ad essere più ameboide in forma e il comportamento che aderiscano alle superfici di vetro. Impiegando criteri pubblicati per la tipizzazione hemocyte e recupero 11, il nostro metodo di raccolta ha prodotto un numero simile di ematociti concentrati totali e abbiamo anche scoperto che i granulociti costituiscono la più alta percentuale di ematociti concentrati totale 11 (Fig. 2). <img src="/files/ftp_upload/2772/2772fig1.jpg" alt="Figura 1" /> Figura 1. Immagini al microscopio luce di un rappresentante HEMA3 fisso, prohemocyte macchiato (A), oenocytoid (B), e dei granulociti (C) da un Ae. aegypti femmina adulta. C = citoplasma, nucleo N = G = granuli. <img src="/files/ftp_upload/2772/2772fig2.jpg" alt="Figura 2"/> Figura 2. Conta totale ± SE di tutti ematociti concentrati e granulociti ottenuta per zanzara femmina dal nostro diluizione emolinfa e metodo di raccolta.

<ol>
	<li>Enayati, A., Hemingway, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Malaria+management:+past,+present,+and+future.">Malaria management: past, present, and future.</a> Annu. Rev. Entomol. 55, 569-569 (2010).</li><li>Medlock, J., Luz, P. M., Struchiner, C. J., Galvani, A. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+transgenic+mosquitoes+on+dengue+virulence+to+humans+and+mosquitoes.">The impact of transgenic mosquitoes on dengue virulence to humans and mosquitoes.</a> The American Naturalist. 174, 565-565 (2009).</li><li>Baton, L. A., Garver, L., Xi, Z., Dimopoulos, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+genomics+studies+on+the+innate+immunity+of+disease+vectors.">Functional genomics studies on the innate immunity of disease vectors.</a> Insect Sci. 15, 15-15 (2008).</li><li>Thomas, R. E., Wu, W. K., Verleye, D., Rai, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Midgut+basal+lamina+thickness+and+dengue-1+virus+dissemination+rates+in+laboratory+strains+of+Aedes+albopictus+(Diptera:+Culicidae).">Midgut basal lamina thickness and dengue-1 virus dissemination rates in laboratory strains of Aedes albopictus (Diptera: Culicidae).</a> J. Med. Entomol. 30, 326-326 (1993).</li><li>Bartholomay, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Profiling+infection+responses+in+the+haemocytes+of+the+mosquito,+Aedes+aegypti.">Profiling infection responses in the haemocytes of the mosquito, Aedes aegypti.</a> Insect Mol. Biol. 16, 761-761 (2007).</li><li>Strand, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+insect+cellular+immune+response.">The insect cellular immune response.</a> Insect Sci. 15, 1-1 (2008).</li><li>Hillyer, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age-associated+mortality+in+immune+challenged+mosquitoes+(Aedes+aegypti)+correlates+with+a+decrease+in+haemocyte+numbers.">Age-associated mortality in immune challenged mosquitoes (Aedes aegypti) correlates with a decrease in haemocyte numbers.</a> Cell. Microbiol. 7, 39-39 (2005).</li><li>Chen, C. C., Laurence, B. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+study+on+humoral+encapsulation+of+microfilariae:+establishment+of+technique+and+description+of+reaction.">In vitro study on humoral encapsulation of microfilariae: establishment of technique and description of reaction.</a> International Journal for Parasitology. 17, 781-781 (1987).</li><li>Beerntsen, B. T., Christensen, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dirofilaria+immitis:+effects+on+hemolymph+polypeptide+synthesis+in+Aedes+aegypti+during+melanotic+encapsulation+reactions+against+Microfilariae.">Dirofilaria immitis: effects on hemolymph polypeptide synthesis in Aedes aegypti during melanotic encapsulation reactions against Microfilariae.</a> Exp. Parasitol. 71, 406-406 (1990).</li><li>Hillyer, J. F., Schmidt, S. L., Christensen, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+antibacterial+innate+immune+response+by+the+mosquito+Aedes+aegypti+is+mediated+by+hemocytes+and+independent+of+Gram+type+and+pathogenicity.">The antibacterial innate immune response by the mosquito Aedes aegypti is mediated by hemocytes and independent of Gram type and pathogenicity.</a> Microb. Infect. 6, 448-448 (2004).</li><li>Castillo, J. C., Robertson, A. E., Strand, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+hemocytes+from+the+mosquitoes+Anopheles+gambiae+and+Aedes+aegypti.">Characterization of hemocytes from the mosquitoes Anopheles gambiae and Aedes aegypti.</a> Insect Biochem. Mol. Biol. 36, 891-891 (2006).</li></ol>

Nessun conflitto di interessi dichiarati.

Il metodo di raccolta hemocyte qui descritto è stato modificato dai metodi precedentemente pubblicato e permette di isolare i preparativi pulita di ematociti concentrati da zanzare Aedes con meno passaggi. Mentre il nostro particolare interesse risiede nel caratterizzare popolazioni hemocyte in zanzare Aedes, crediamo che questa tecnica può essere applicata a gruppi di altre zanzare, dopo gli studi iniziali condotti per determinare il volume d&#39;iniezione appropriate. Il nostro protocollo utilizza ...

<table border="1"><tbody><tr><th> Nome del reagente </th><th> Azienda </th><th> Numero di catalogo </th><th> Commenti (opzionale) </th></tr><tr><td> Media Schneider </td><td> Sigma-Aldrich </td><td> S0146 </td><td></td></tr><tr><td> Siero fetale bovino </td><td> Sigma-Aldrich </td><td> F0643 </td><td></td></tr><tr><td> Hema3 kit macchia </td><td> Pescatore </td><td> 123-869 </td><td></td></tr><tr><td> Vetro aghi (Borosilicato con filamento) </td><td> Sutter strumento </td><td> BF100-78-10 </td><td> 1,0 millimetri OD e 0,78 millimetri ID </td></tr><tr><td> Ago estrattore </td><td> Sutter Instruments </td><td> Modello P-87 </td><td></td></tr><tr><td> MicroInjector </td><td> Tritech di ricerca </td><td> Minj-PD </td><td></td></tr><tr><td> Porta aghi </td><td> Tritech di ricerca </td><td> Minj-4 </td><td></td></tr></tbody></table>

a protocol for collecting and staining hemocytes from the yellow fever mosquito aedes aegypti

Le zanzare sono vettori di una serie di agenti patogeni che causano malattie come il virus della febbre gialla, malaria, parassiti e vermi filarial. Laboratori stanno studiando anti-patogeno componenti del sistema immunitario innato nella specie dei vettori di malattie, nella speranza di generare zanzare transgeniche che sono refrattari agli agenti patogeni quali 1, 2. Il sistema immunitario innato di zanzare è composto da diverse linee di difesa 3. Agenti patogeni che riescono a sfuggire alla barriera imposta dalla epitelio-allineata zanzara midgut 4 Inserire il emolinfa e di incontro ematociti concentrati in circolazione, importanti componenti cellulari che incapsulano e patogeni fagocitare 5, 6. I ricercatori non hanno trovato prove per i tessuti emopoietici in zanzare e fatti suggeriscono che il numero di ematociti concentrati è fissato a emergere per adulti e numeri può effettivamente diminuire con l&#39;invecchiamento della zanzara 7. La capacità di raccogliere correttamente e identificare ematociti concentrati dagli insetti medicalmente importante è un passo essenziale per gli studi di immunità cellulare. Tuttavia, la dimensione piccola delle zanzare e il volume limitato di emolinfa rappresentano una sfida a raccogliere le cellule immunitarie. Due metodi per la raccolta di ematociti concentrati zanzara comprendono espulsione di emolinfa da un taglio proboscide 8, e lo spostamento del volume (perfusione), in cui viene iniettato soluzione salina nella regione membranosa necklike tra la testa e torace (cioè, cervice) e la perfusione emolinfa viene raccolta da un&#39;apertura strappato in una regione distale dell&#39;addome 9, 10. Queste tecniche, tuttavia, sono limitate da basso recupero di ematociti concentrati e di possibile contaminazione da parte delle cellule di grasso corporeo, rispettivamente 11. Più recentemente un metodo denominato di iniezione ad alta / recupero di un migliore recupero immunocytes mediante l&#39;uso di tamponi anticoagulanti, riducendo i livelli di contaminanti scale e tessuti interni 11. Anche se questo metodo permette un metodo migliorato di raccolta e di conservazione ematociti concentrati per la cultura primaria, che comporta un certo numero di iniezione e fasi di raccolta che non sono necessari se l&#39;obiettivo a valle è quello di raccogliere, fissare e macchia ematociti concentrati per la diagnostica. Qui, dimostriamo il nostro metodo di raccolta emolinfa zanzara che unisce la semplicità di perfusione, utilizzando tamponi anticoagulante al posto della soluzione fisiologica, con la precisione delle tecniche di iniezione ad alta isolare i preparativi pulita di ematociti concentrati in Aedes zanzare.

Watch this Scientific Journal Video about A Protocol for Collecting and Staining Hemocytes from the Yellow Fever Mosquito Aedes aegypti at JoVE.com

A Protocol for Collecting and Staining Hemocytes from the Yellow Fever Mosquito Aedes aegypti

Un semplice ma accurato metodo per raccogliere e macchia ematociti concentrati zanzara è descritto. Il nostro metodo combina la semplicità di perfusione con la precisione delle tecniche di iniezione ad alta isolare i preparativi pulita di ematociti concentrati in Aedes zanzare. Questo metodo facilita la conoscenza di studi che richiedono i tipi di ematociti concentrati e la loro abbondanza.

Un protocollo per la raccolta e la colorazione ematociti concentrati dal Mosquito febbre gialla Aedes aegypti</em

 Mosquitoes are vectors for a number  of disease-causing pathogens such as the yellow fever virus, malaria parasites  and filarial worms. Laboratories are ...

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Research

JoVE Journal

Immunology and Infection

A Protocol for Collecting and Staining Hemocytes from the Yellow Fever Mosquito Aedes aegypti

15.2K Views.  University of Richmond. Un semplice ma accurato metodo per raccogliere e macchia ematociti concentrati zanzara è descritto. Il nostro metodo combina la semplicità di perfusione con la precisione delle tecniche di iniezione ad alta isolare i preparativi pulita di ematociti concentrati in Aedes zanzare. Questo metodo facilita la conoscenza di studi che richiedono i tipi di ematociti concentrati e la loro abbondanza.

Video: A Protocol for Collecting and Staining Hemocytes from the Yellow Fever Mosquito Aedes aegypti

Protocol for Production of a Genetic Cross of the Rodent Malaria Parasites

Variation in response to antimalarial drugs and in pathogenicity of malaria parasites is of biologic and medical importance. Linkage mapping has led to successful identification of genes or loci underlying various traits in malaria parasites of rodents1-3 and humans4-6. The malaria parasite Plasmodium yoelii is one of many malaria species isolated from wild African rodents and has been adapted to grow in laboratories. This species reproduces many of the biologic characteristics of the human malaria parasites; genetic markers such as microsatellite and amplified fragment length polymorphism (AFLP) markers have also been developed for the parasite7-9. Thus, genetic studies in rodent malaria parasites can be performed to complement research on Plasmodium falciparum. Here, we demonstrate the techniques for producing a genetic cross in P. yoelii that were first pioneered by Drs. David Walliker, Richard Carter, and colleagues at the University of Edinburgh10.

Genetic crosses in P. yoelii and other rodent malaria parasites are conducted by infecting mice Mus musculus with an inoculum containing gametocytes of two genetically distinct clones that differ in phenotypes of interest and by allowing mosquitoes to feed on the infected mice 4 days after infection. The presence of male and female gametocytes in the mouse blood is microscopically confirmed before feeding. Within 48 hrs after feeding, in the midgut of the mosquito, the haploid gametocytes differentiate into male and female gametes, fertilize, and form a diploid zygote (Fig. 1). During development of a zygote into an ookinete, meiosis appears to occur11. If the zygote is derived through cross-fertilization between gametes of the two genetically distinct parasites, genetic exchanges (chromosomal reassortment and cross-overs between the non-sister chromatids of a pair of homologous chromosomes; Fig. 2) may occur, resulting in recombination of genetic material at homologous loci. Each zygote undergoes two successive nuclear divisions, leading to four haploid nuclei. An ookinete further develops into an oocyst. Once the oocyst matures, thousands of sporozoites (the progeny of the cross) are formed and released into mosquito hemoceal. Sporozoites are harvested from the salivary glands and injected into a new murine host, where pre-erythrocytic and erythrocytic stage development takes place. Erythrocytic forms are cloned and classified with regard to the characters distinguishing the parental lines prior to genetic linkage mapping. Control infections of individual parental clones are performed in the same way as the production of a genetic cross.

Genetic crosses of rodent malaria parasites are performed by feeding two genetically distinct parasites to mosquitoes. Recombinant progeny are cloned from mouse blood after allowing mosquitoes to bite infected mice. This video shows how to produce genetic crosses of Plasmodium yoelii and is applicable to other rodent malaria parasites.

Protocollo per la produzione di un incrocio fra i roditori parassiti della malaria

Variation in response to antimalarial drugs and in pathogenicity of malaria parasites is of biologic and medical importance. Linkage mapping has led to ...

Ricerca

Immunologia e infezioni

A Calcium Bioluminescence Assay for Functional Analysis of Mosquito (Aedes aegypti) and Tick (Rhipicephalus microplus) G Protein-coupled Receptors

Arthropod hormone receptors are potential targets for novel pesticides as they regulate many essential physiological and behavioral processes. The majority of them belong to the superfamily of G protein-coupled receptors (GPCRs). We have focused on characterizing arthropod kinin receptors from the tick and mosquito. Arthropod kinins are multifunctional neuropeptides with myotropic, diuretic, and neurotransmitter function. Here, a method for systematic analyses of structure-activity relationships of insect kinins on two heterologous kinin receptor-expressing systems is described. We provide important information relevant to the development of biostable kinin analogs with the potential to disrupt the diuretic, myotropic, and/or digestive processes in ticks and mosquitoes.
The kinin receptors from the southern cattle tick, Boophilus microplus (Canestrini), and the mosquito Aedes aegypti (Linnaeus), were stably expressed in the mammalian cell line CHO-K1. Functional analyses of these receptors were completed using a calcium bioluminescence plate assay that measures intracellular bioluminescence to determine cytoplasmic calcium levels upon peptide application to these recombinant cells. This method takes advantage of the aequorin protein, a photoprotein isolated from luminescent jellyfish. We transiently transfected the aequorin plasmid (mtAEQ/pcDNA1) in cell lines that stably expressed the kinin receptors. These cells were then treated with the cofactor coelenterazine, which complexes with intracellular aequorin. This bond breaks in the presence of calcium, emitting luminescence levels indicative of the calcium concentration. As the kinin receptor signals through the release of intracellular calcium, the intensity of the signal is related to the potency of the peptide.
This protocol is a synthesis of several previously described protocols with modifications; it presents step-by-step instructions for the stable expression of GPCRs in a mammalian cell line through functional plate assays (Staubly et al., 2002 and Stables et al., 1997). Using this methodology, we were able to establish stable cell lines expressing the mosquito and the tick kinin receptors, compare the potency of three mosquito kinins, identify critical amino acid positions for the ligand-receptor interaction, and perform semi-throughput screening of a peptide library. Because insect kinins are susceptible to fast enzymatic degradation by endogenous peptidases, they are severely limited in use as tools for pest control or endocrinological studies. Therefore, we also tested kinin analogs containing amino isobutyric acid (Aib) to enhance their potency and biostability. This peptidase-resistant analog represents an important lead in the development of biostable insect kinin analogs and may aid in the development of neuropeptide-based arthropod control strategies.

A Calcium Bioluminescence Assay for Functional Analysis of Mosquito Aedes aegypti and Tick Rhipicephalus microplus G Protein-coupled Receptors

This protocol provides instructions for clonal-cell line selection and a calcium bioluminescence assay to analyze the structure-activity relationships of synthesized arthropod neuropeptides on their cognate GPCRs. This assay can be used for receptor deorphanization and structure-activity relationship studies for synthetic analog design and peptide/drug-lead discovery.

Un saggio di calcio bioluminescenza di analisi funzionale del Mosquito ( Aedes aegypti) E Tick ( Rhipicephalus Microplus) G recettori accoppiati alla proteina

Arthropod hormone receptors are potential targets for novel pesticides as they regulate many essential physiological and behavioral processes.  The ...

A Simple Chelex Protocol for DNA Extraction from Anopheles spp.

Endemic countries are increasingly adopting molecular tools for efficient typing, identification and surveillance against malaria parasites and vector mosquitoes, as an integral part of their control programs1,2,3,4,5. For sustainable establishment of these accurate approaches in operations research to strengthen malaria control and elimination efforts, simple and affordable methods, with parsimonious reagent and equipment requirements are essential6,7,8. Here we present a simple Chelex-based technique for extracting malaria parasite and vector DNA from field collected mosquito specimens.
We morphologically identified 72 Anopheles gambiae sl. from 156 mosquitoes captured by pyrethrum spray catches in sleeping rooms of households within a 2,000 km2 vicinity of the Malaria Institute at Macha. After dissection to separate the head and thorax from the abdomen for all 72 Anopheles gambiae sl. mosquitoes, the two sections were individually placed in 1.5 ml microcentrifuge tubes and submerged in 20 &mu;l of deionized water. Using a sterile pipette tip, each mosquito section was separately homogenized to a uniform suspension in the deionized water. Of the ensuing homogenate from each mosquito section, 10 &mu;l was retained while the other 10 &mu;l was transferred to a separate autoclaved 1.5 ml tube. The separate aliquots were subjected to DNA extraction by either the simplified Chelex or the standard salting out extraction protocol9,10. The salting out protocol is so-called and widely used because it employs high salt concentrations in lieu of hazardous organic solvents (such as phenol and chloroform) for the protein precipitation step during DNA extraction9.
Extracts were used as templates for PCR amplification using primers targeting arthropod mitochondrial nicotinamide adenine dinucleotide dehydrogenase (NADH) subunit 4 gene (ND4) to check DNA quality11, a PCR for identification of Anopheles gambiae sibling species10 and a nested PCR for typing of Plasmodium falciparum infection12. Comparison using DNA quality (ND4) PCR showed 93% sensitivity and 82% specificity for the Chelex approach relative to the established salting out protocol. Corresponding values of sensitivity and specificity were 100% and 78%, respectively, using sibling species identification PCR and 92% and 80%, respectively for P. falciparum detection PCR. There were no significant differences in proportion of samples giving amplicon signal with the Chelex or the regular salting out protocol across all three PCR applications. The Chelex approach required three simple reagents and 37 min to complete, while the salting out protocol entailed 10 different reagents and 2 hr and 47 min' processing time, including an overnight step. Our results show that the Chelex method is comparable to the existing salting out extraction and can be substituted as a simple and sustainable approach in resource-limited settings where a constant reagent supply chain is often difficult to maintain.

A Simple Chelex Protocol for DNA Extraction from Anopheles spp.

A rapid and affordable way to extract quality malaria parasite and vector DNA from mosquito specimens is described. Capitalizing on chelating properties of Chelex resin, the simple method enables genotyping of malaria parasites in mosquito mid-gut and salivary gland phases, as well as molecular identification of the Anopheles sibling species by PCR.

Un protocollo Chelex semplice per l&#39;estrazione del DNA da<em&gt; Anopheles</em&gt; Spp.

Endemic countries are increasingly adopting molecular tools for  efficient typing, identification and surveillance against malaria parasites and  vector ...

A Protocol for Analyzing Hepatitis C Virus Replication

Hepatitis C Virus (HCV) affects 3% of the world&#8217;s population and causes serious liver ailments including&#160;chronic hepatitis, cirrhosis, and hepatocellular carcinoma. HCV is an enveloped RNA virus belonging to the family Flaviviridae. Current treatment is not fully effective and causes adverse side effects. There is no HCV vaccine available. Thus, continued effort is required for developing a vaccine and better therapy. An HCV cell culture system is critical for studying various stages of HCV growth including viral entry, genome replication, packaging, and egress. In the current procedure presented, we used a wild-type intragenotype 2a chimeric virus, FNX-HCV, and a recombinant FNX-Rluc virus carrying a Renilla luciferase reporter gene to study the virus replication. A human hepatoma cell line (Huh-7 based) was used for transfection of in vitro transcribed HCV genomic RNAs. Cell-free culture supernatants, protein lysates and total RNA were harvested at various time points post-transfection to assess HCV growth. HCV genome replication status was evaluated by quantitative RT-PCR and visualizing the presence of HCV double-stranded RNA. The HCV protein expression was verified by Western blot and immunofluorescence assays using antibodies specific for HCV NS3 and NS5A proteins. HCV RNA transfected cells released infectious particles into culture supernatant and the viral titer was measured. Luciferase assays were utilized to assess the replication level and infectivity of reporter HCV. In conclusion, we present various virological assays for characterizing different stages of the HCV replication cycle.

Hepatitis C Virus (HCV) is a major human pathogen that causes liver disorders, including cirrhosis and cancer. An HCV infectious cell culture system is essential for understanding the molecular mechanism of HCV replication and developing new therapeutic approaches. Here we describe a protocol to investigate various stages of the HCV replication cycle.

Un protocollo per l&#39;analisi dell&#39;epatite C replicazione del virus

Hepatitis C Virus (HCV) affects 3% of the world&#8217;s population and causes serious liver ailments including&#160;chronic hepatitis, cirrhosis, and ...

Extraction of Hemocytes from Drosophila melanogaster Larvae for Microbial Infection and Analysis

During the pathogenic infection of Drosophila melanogaster, hemocytes play an important role in the immune response throughout the infection. Thus, the goal of this protocol is to develop a method to visualize the pathogen invasion in a specific immune compartment of flies, namely hemocytes. Using the method presented here, up to 3 &#215; 106 live hemocytes can be obtained from 200 Drosophila 3rd instar larvae in 30 min for ex vivo infection. Alternatively, hemocytes can be infected in vivo through injection of 3rd instar larvae followed by hemocyte extraction up to 24 h post-infection. These infected primary cells were fixed, stained, and imaged using confocal microscopy. Then, 3D representations were generated from the images to definitively show pathogen invasion. Additionally, high-quality RNA for qRT-PCR can be obtained for the detection of pathogen mRNA following infection, and sufficient protein can be extracted from these cells for Western blot analysis. Taken together, we present a method for definite reconciliation of pathogen invasion and confirmation of infection using bacterial and viral pathogen types and an efficient method for hemocyte extraction to obtain enough live hemocytes from Drosophila larvae for ex vivo and in vivo infection experiments.

Extraction of Hemocytes from Drosophila melanogaster Larvae for Microbial Infection and Analysis

This method demonstrates how to visualize pathogen invasion into insect cells with three-dimensional (3D) models. Hemocytes from Drosophila larvae were infected with viral or bacterial pathogens, either ex vivo or in vivo. Infected hemocytes were then fixed and stained for imaging with a confocal microscope and subsequent 3D cellular reconstruction.

Estrazione di emociti da larve di Drosophila melanogaster per infezione microbica e l'analisi

During the pathogenic infection of Drosophila melanogaster, hemocytes play an important role in the immune response throughout the infection. Thus, the ...

Co-staining Blood Vessels and Nerve Fibers in Adipose Tissue

Recent studies have highlighted the critical role of angiogenesis and sympathetic innervation in adipose tissue remodeling during the development of obesity. Therefore, developing an easy and efficient method to document the dynamic changes in adipose tissue is necessary. Here, we describe a modified immunofluorescent approach that efficiently co-stains blood vessels and nerve fibers in adipose tissues. Compared to traditional and recently developed methods, our approach is relatively easy to follow and more efficient in labeling the blood vessels and nerve fibers with higher densities and less background. Moreover, the higher resolution of the images further allows us to accurately measure the area of the vessels, amount of branching, and length of the fibers by open source software. As a demonstration using our method, we show that brown adipose tissue (BAT) contains higher amounts of blood vessels and nerve fibers compared to white adipose tissue (WAT). We further find that among the WATs, subcutaneous WAT (sWAT) has more blood vessels and nerve fibers compared to epididymal WAT (eWAT). Our method thus provides a useful tool for investigating adipose tissue remodeling.

New blood vessel formation and sympathetic innervation play pivotal roles in adipose tissue remodeling. However, there remain technical issues in visualizing and quantitatively measuring adipose tissue. Here we present a protocol to successfully label and quantitatively compare the densities of blood vessels and nerve fibers in different adipose tissues.

Co-macchiatura dei vasi sanguigni e fibre nervose nel tessuto adiposo

Recent studies have highlighted the critical role of angiogenesis and sympathetic innervation in adipose tissue remodeling during the development of ...

In Vitro ELISA Test to Evaluate Rabies Vaccine Potency

The growing global concern for the animal welfare is encouraging manufacturers and the National Control Laboratories (OMCLs) to follow the 3Rs strategy for the Replacement, Reduction, and Refinement of the laboratory animal testing. The development of in vitro approaches is recommended at the WHO and European levels as alternatives to the NIH test for evaluating the rabies vaccine potency. At the surface of the rabies virus (RABV) particle, trimers of glycoprotein constitute the major immunogen to induce Viral Neutralizing Antibodies (VNAbs). An ELISA test, where Neutralizing Monoclonal Antibodies (mAb-D1) recognize the trimeric form of the glycoprotein, has been developed to determine the contents of the native folded trimeric glycoprotein along with the production of the vaccine batches. This in vitro potency test demonstrated a good concordance with the NIH test and has been found suitable in collaborative trials by RABV vaccine manufacturers and OMCLs. Avoidance of animal use is an achievable objective in the near future.
The method presented is based on an indirect ELISA sandwich immunocapture using the mAb-D1 which recognizes the antigenic sites III (aa 330 to 338) of the trimeric RABV glycoprotein, i.e., the immunogenic RABV antigen. mAb-D1 is used for both coating and detection of glycoprotein trimers present in the vaccine batch. Since the epitope is recognized because of its conformational properties, the potentially denatured glycoprotein (less immunogenic) cannot be captured and detected by the mAb-D1. The vaccine to be tested is incubated in a plate sensitized with the mAb-D1. Bound trimeric RABV glycoproteins are identified by adding the mAb-D1 again, labeled with peroxidase and then revealed in the presence of substrate and chromogen. Comparison of the absorbance measured for the tested vaccine and the reference vaccine allows for the determination of the immunogenic glycoprotein content.

Here we describe an indirect ELISA sandwich immunocapture to determine the immunogenic glycoprotein contents in rabies vaccines. This test uses a neutralizing Monoclonal Antibody (mAb-D1) recognizing glycoprotein trimers. It is an alternative to the in vivo NIH test to follow the consistency of vaccine potency during production.

Test ELISA in vitro per valutare la potenza del vaccino contro la rabbia

The growing global concern for the animal welfare is encouraging manufacturers and the National Control Laboratories (OMCLs) to follow the 3Rs strategy ...

Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus

The procedures presented describe a generalized methodology to infect Aedes aegypti mosquitoes with Zika virus under laboratory conditions to determine the rate of infection, disseminated infection, and potential transmission of the virus in the mosquito population in question. These procedures are widely utilized with various modifications in vector competence evaluations globally. They are important in determining the potential role that a given mosquito (i.e., species, population, individual) may play in the transmission of a given agent.

Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus

The presented protocol can determine the vector competence of Aedes aegypti mosquito populations for a given virus, such as Zika, in a containment setting.

Analisi di competenza vettoriale sulle zanzare Aedes aegypti utilizzando il virus Zika

The procedures presented describe a generalized methodology to infect Aedes aegypti mosquitoes with Zika virus under laboratory conditions to determine ...

Propagation of the Microsporidian Parasite Edhazardia aedis in Aedes aegypti Mosquitoes

Edhazardia aedis is a microsporidian parasite of Aedes aegypti mosquitoes, a disease vector that transmits multiple arboviruses which cause millions of disease cases each year. E. aedis causes mortality and reduced reproductive fitness in the mosquito vector and has been explored for its potential as a biocontrol agent. The protocol we present for culturing E. aedis is based on its natural infection cycle, which involves both horizontal and vertical transmission at different life stages of the mosquito host. Ae. aegypti mosquitoes are exposed to spores in the larval stage. These infected larvae then mature into adults and transmit the parasite vertically to their offspring. Infected offspring are then used as a source of spores for future horizontal transmission. Culturing E. aedis can be challenging to the uninitiated given the complexities of the parasite&#8217;s life cycle, and this protocol provides detailed guidance and visual aids for clarification.

Propagation of the Microsporidian Parasite Edhazardia aedis in Aedes aegypti Mosquitoes

A protocol to culture the microsporidian parasite Edhazardia aedis. The parasite is passaged from one generation of Aedes aegypti mosquitoes to the next via horizontal transfer at the larval stage followed by vertical transmission at the adult stage. Live sporoplasms survive long-term in infected eggs.

Propagazione del parassita microsporidiano Edhazardia aedis nelle zanzare Aedes aegypti

Edhazardia aedis is a microsporidian parasite of Aedes aegypti mosquitoes, a disease vector that transmits multiple arboviruses which cause millions of ...

Feeding and Quantifying Animal-Derived Blood and Artificial Meals in Aedes aegypti Mosquitoes

Females of certain mosquito species can spread diseases while biting vertebrate hosts to obtain protein-rich blood meals required for egg development. In the laboratory, researchers can deliver animal-derived and artificial blood meals to mosquitoes via membrane feeders, which allow for manipulation of meal composition. Here, we present methods for feeding blood and artificial blood meals to Aedes aegypti mosquitoes and quantifying the volume consumed by individual females.
Targeted feeding and quantification of artificial/blood meals have broad uses, including testing the effects of meal components on mosquito behavior and physiology, delivering pharmacological compounds without injection, and infecting mosquitoes with specific pathogens. Adding fluorescein dye to the meal prior to feeding allows for subsequent meal size quantification. The meal volume consumed by mosquitoes can be measured either by weight, if the females are to be used later for behavioral experiments, or by homogenizing individual females in 96-well plates and measuring fluorescence levels using a plate reader as an endpoint assay. Meal size quantification can be used to determine whether changing the meal components alters the meal volume ingested or if meal consumption differs between mosquito strains. Precise meal size quantification is also critical for downstream assays, such as those measuring effects on host attraction or fecundity. The methods presented here can be further adapted to track meal digestion over the course of days or to include multiple distinguishable markers added to different meals (like nectar and blood) to quantify the consumption of each meal by a single mosquito.
These methods allow researchers to singlehandedly perform high-throughput measurements to compare the meal volume consumed by hundreds of individual mosquitoes. These tools will therefore be broadly useful to the community of mosquito researchers for answering diverse biological questions.

Feeding and Quantifying Animal-Derived Blood and Artificial Meals in Aedes aegypti Mosquitoes

The goal of this protocol is to deliver animal-derived and artificial blood meals to Aedes aegypti mosquitoes through an artificial membrane feeder and precisely quantify the volume of meal ingested.

Alimentazione e quantificazione del sangue di origine animale e dei pasti artificiali nelle zanzare Aedes aegypti

Females of certain mosquito species can spread diseases while biting vertebrate hosts to obtain protein-rich blood meals required for egg development. In ...