Autoren möchten John Frey und Ben Peterson für Moskito Aufzucht danken. Wir danken auch Christine Davis und Gary Radice für die Hilfe bei hemocyte Aufnahmen. Diese Arbeit wurde von der University of Richmond Arts &amp; Science Sommer Stipendium für AA Qayum und Dozenten zu gewähren A. Telang finanziert.

1. Vorbereitung im Vorfeld der hemocyte Sammlung <ol><li> Bereiten Sie eine Hämolymphe Verdünnungsmittel Lösung, die von 60% Schneider-Medium, 10% fötalem Rinderserum (FBS), und 30% Citratpuffer besteht (Antikoagulans, 98 mM NaOH, 186 mM NaCl, 1,7 mM EDTA, 41 mM Zitronensäure, pH 4,5) 11. Machen Sie 1,0 ml Aliquots, die bei -20 ° C gelagert werden können Verwenden Sie jedes Aliquot nur einmal (siehe Materialien). </li><li> Bereiten Objektträger aus Glas (75 x 25 x 1 mm) durch Scoring ein 1 cm Durchmesser-Kreis an einem Ende mit einem Glas-Ätz-Tool. Alternativ können Objektträger mit zwei vorgeätzt Kreisen erworben (z. B. Fisher Scientific oder EMS Quellen) werden. Ein Glas Folie pro Moskito benötigt werden. </li><li> Einen Satz von Glas-Nadeln (siehe Materialien) zog nach dem folgenden vorgeschlagenen Einstellungen (Sutter Instruments, Modell P-87): <table border="1"><tbody><tr><td> Hitze Ramp 5 </td></tr><tr><td> Pull: 45 </td></tr><tr><td> Vel: 75 </td></tr><tr><td> Zeit: 175 </td></tr><tr><td> Pressure 580 </td></tr></tbody></table> Unter den empfohlenen Einstellungen auf dieser Abzieher, konstruieren wir Nadeln, die sich um 500 mm sind in der gesamten Länge mit Schaft Längen von ca. 3 mm. Pre-gezogen Nadeln können auch gekauft (zB Tritech Research) werden. </li></ol> 2. Vorbereitung der Mikroinjektor im Vorfeld der hemocyte Sammlung <ol><li> Legen Sie eine gezogen Nadel in die Mikroinjektor Nadelhalter nach den Anweisungen des Herstellers. Backfill die Mikroinjektor (siehe Materialien) Schlauch, Spritze und zog Glasnadel mit Mineralöl nach den Anweisungen des Herstellers. </li></ol> 3. Vorbereitung der weiblichen Mücken im Vorfeld der hemocyte Sammlung <ol><li> Saugen Sie 15 erwachsene Weibchen in kleine Massivkäfig Containern, die in Kontakt mit dem Eis werden können. Tauchen Käfig mit Stechmücken in Eis tief genug, so dass gesamte Höhe des Käfigs und alle Seiten sind in Kontakt mit dem Eis. Dadurch wird sichergestellt, dass alle Mücken auf die Kälte ausgesetzt werden. Kalte betäuben Mücken für ca. 8 Minuten oder bis sie nicht mehr mobil. </li><li> Legen Sie eine Mücke auf eine Depression gleiten. Diese Folie wird als Standort für Injektionen dienen. </li></ol> 4. Hemocyte Sammlung <ol><li> Stellen Sie die Mikroinjektor aufnehmen 12 ul Hämolymphe Verdünnungsmittel in gezapftes Nadel und Injektion Lösung in der Mücke zwischen der siebten und achten Abdominalsegmente. Etwa 3 Mücken können mit 3-3,5 ul der insgesamt 12 ul Volumen aufgenommen injiziert werden. Die Mücke sollte vorsichtig vorhanden sein, mit einer Pinzette gehalten, während Injektion durchgeführt wird. Ein kleines Volumen des Lösungsmittels sollte an der Spitze der Nadel bleiben, so dass Mineralöl aus der Injektion zu verhindern. Nach der Injektion der Bauch aussehen sollte &quot;gefüllt&quot; oder aufgedunsen. </li><li> Legen Sie injizierten Moskitos in einem separaten sauberen Behälter auf Eis für 5 min zu erholen. Die Inkubationszeit des Antikoagulans Verdünnungslösung innerhalb der Mücke wird dazu beitragen, zu vertreiben Haemocyten Einhaltung interner Gewebe. Im Durchschnitt 3 bis 5 frische Mücken können während jeweils 5 min Erholungszeit injiziert werden. </li><li> Nach 5 Minuten der Erholung, snip off Beine, Flügel und die Spitze des Bauches (an der achten Segment) jeder Mücke ein zu einer Zeit mit Mikro Schere. Dies sollte in der Erholung Tasse auf Eis gelegt, durchgeführt werden. Das Abschneiden der Beine und Flügel reduziert die Wahrscheinlichkeit von Skalen wird die Sammlung Dias übertragen. Achtung: nicht die Beine abgeschnitten und Flügeln zu nah an Brust-Bindungsstellen in der Nähe, oder Sie das Risiko einer weiteren Öffnungen für Hämolymphe zu entkommen. Hämolymphe sollte nur durch die Öffnung an der Spitze des Bauches geschaffen gesammelt werden. </li><li> Wash ein Glas geätzt Objektträger mit 70% Ethanol und trocknen Sie sie mit einem Kimwipe. Positionieren Sie eine injiziert und Mücke wieder auf der Folie auf dem äußeren Rand der geätzten Kreis. Set Mikroinjektor abholen 12 ul frisches Hämolymphe Verdünnungsmittel und injizieren dieses Volumen in der Mücke in der lateralen Seite der Mesothorax. Deliver meisten, aber nicht das gesamte Volumen des Lösungsmittels (ca. 8 bis 10 ul), so dass Mineralöl aus der Injektion zu verhindern. Ein kleines Volumen des Lösungsmittels sollte an der Spitze der Nadel bleiben. </li><li> Position der Mücke, so dass der Schnitt abdominale Öffnung am Rand der 1-cm-Kreis ist. Nach der Injektion der verdünnten Hämolymphe sollte innerhalb der markierten Fläche gesammelt werden. Sobald die Nadel aus der mesothoracic Injektionsstelle entfernt wird, wieder hält der Mücke zwischen den beiden Armen der Zange und drücken Sie leicht den Bauch mit den Zangen der Hämolymphe auf die geätzte Kreisfläche zu lenken. </li><li> Lassen verdünnt Hämolymphe auf Folie für ca. 10 Minuten oder bis sie sichtbar trocken trocken. </li></ol> 5. Hemocyte Fixierung und Färbung <ol><li> Stain jede Folie einzeln mit HEMA3 7 (siehe Materialien): Dip slide in Fixativ 5 Mal für jeweils 1 Sekunde Zeit, Dipslide in Lösung, die ich 3 mal für jeweils 1 Sekunde, und schließlich, dip slide in Lösung II 3-mal für jeweils 1 Sekunde. Spülen Sie die Rückseite der Folie mit DI-Wasser. Die Vorderseite der Folie sollte nicht gespült werden. Blot-dry der Vorderseite der Folie außerhalb geätzt Kreis mit gefärbten Gewebeschnitten. </li><li> Bewerben Eindeckmedium (z. B. Shur / Mount oder Polymount) rund um die geätzten Zentrum und Ort ein Deckglas darauf. Drücken Sie leicht auf das Deckglas (25 x 25 mm), so dass die Montage Medium breitet sich der gesamte Bereich durch das Deckglas (einschließlich geätzt Kreis mit gefärbten Gewebeschnitten) abgedeckt. Lassen Sie die Objektträger für mindestens 3 Stunden oder über Nacht trocknen lassen. Blutzellen sollten innerhalb von 2 Wochen nach der Entnahme für eine optimale Visualisierung und Bildgebung betrachtet werden. </li></ol> 6. Repräsentative Ergebnisse Beispiele für feste und HEMA3 gefärbten Blutzellen aus einer Aedes aegypti erwachsenen weiblichen gesammelt sind in Abbildung 1A-C gezeigt. Abbildung 1A zeigt eine hemocyte, dass wir als prohemocyte auf seine geringe Größe, kugelig-runde Form und hohe nukleare um Zytoplasma-Verhältnis (550x Vergrößerung) 11 Basis identifiziert. Abbildung 1B zeigt eine hemocyte als oenocytoid auf seiner Kugelform und hohe Zytoplasma der nuklearen Verhältnis (550x Vergrößerung) klassifiziert. Schließlich zeigt Abbildung 1C ein Granulozyten-type hemocyte (550x Vergrößerung). Granulozyten sind detailliertere in der Natur und sind eher amöboiden in Gestalt und Verhalten als sie sich an Glasflächen. Mit bisher veröffentlichten Kriterien für hemocyte Eingabe-und Recovery-11, ergab unsere Sammlung Methode eine ähnliche Zahl von insgesamt Blutzellen und wir ebenfalls festgestellt, dass Granulozyten bilden den größten Anteil der insgesamt Haemocyten 11 (Abb. 2). <img src="/files/ftp_upload/2772/2772fig1.jpg" alt="Abbildung 1" /> Abbildung 1. Lichtmikroskopische Aufnahmen einer repräsentativen HEMA3 fixiert, gefärbt prohemocyte (A), oenocytoid (B) und Granulozyten (C) aus einer Ae. aegypti erwachsenen Weibchen. C = Cytoplasma, N = Kern G = Granulat. <img src="/files/ftp_upload/2772/2772fig2.jpg" alt="Abbildung 2"/> Abbildung 2. Insgesamt zählt ± SE aller Blutzellen und Granulozyten pro Weibchen Mücke durch unsere Hämolymphe Verdünnung und Erhebungsmethode erhalten.

<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>

Die hemocyte Sammlung hier beschriebene Methode ist aus bisher publizierten Methoden modifiziert und erlaubt es, saubere Vorbereitung der Blutzellen von Aedes Moskitos mit weniger Schritten zu isolieren. Während unser besonderes Interesse liegt in der Charakterisierung hemocyte Populationen in Aedes Mücken, glauben wir, diese Technik auf andere Mücke Gruppen angewendet werden kann, nachdem erste Versuche durchgeführt werden, um eine ordnungsgemäße Injektionsvolumina zu bestimmen. Unser Protokoll ...

<table border="1"><tbody><tr><th> Name des Reagenzes </th><th> Firma </th><th> Katalog-Nummer </th><th> Kommentare (optional) </th></tr><tr><td> Schneider-Medium </td><td> Sigma-Aldrich </td><td> S0146 </td><td></td></tr><tr><td> Rinderfötenserum </td><td> Sigma-Aldrich </td><td> F0643 </td><td></td></tr><tr><td> Hema3 Fleck-Kit </td><td> Fischer </td><td> 123-869 </td><td></td></tr><tr><td> Glasnadeln (Borosilikatglas mit Filament) </td><td> Sutter Instrument </td><td> BF100-78 bis 10 </td><td> 1,0 OD und 0.78mm ID </td></tr><tr><td> Needle Puller </td><td> Sutter Instruments </td><td> Modell P-87 </td><td></td></tr><tr><td> Mikroinjektor </td><td> Tritech Forschung </td><td> Minj-PD </td><td></td></tr><tr><td> Nadelhalter </td><td> Tritech Forschung </td><td> Minj-4 </td><td></td></tr></tbody></table>

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

Moskitos sind Vektoren für eine Reihe von Krankheitserregern wie das Gelbfieber-Virus, Malaria Parasiten und Filarien. Laboratories untersuchen anti-Erreger Bestandteile des angeborenen Immunsystems in Krankheitsüberträgern Arten in der Hoffnung, von transgenen Mücken, die refraktär gegenüber solchen Pathogenen 1, 2 sind. Das angeborene Immunsystem der Moskitos besteht aus mehreren Zeilen Defense 3. Erreger, die die Barriere durch das Epithel ausgekleideten Moskito Mitteldarm 4 verhängten entkommen geben Sie die Hämolymphe und Begegnung zirkulierenden Blutzellen, wichtige zelluläre Komponenten kapseln und zu verschlingen Krankheitserreger 5, 6. Forscher haben keine Beweise für hämatopoetische Gewebe in Mücken gefunden und aktuelle Hinweise darauf, dass die Anzahl der Blutzellen bei Erwachsenen Entstehung ist fest und Zahlen können tatsächlich als die Mücke im Alter von 7 zurück. Die Fähigkeit, richtig zu sammeln und zu identifizieren Blutzellen von medizinisch wichtigen Insekten ist ein wesentlicher Schritt für das Studium der zellulären Immunität. Allerdings stellen die geringe Größe der Mücken und der begrenzten Volumen von Hämolymphe eine Herausforderung für das Sammeln Immunzellen. Zwei etablierte Methoden für die Erfassung Mücke Blutzellen gehören Vertreibung der Hämolymphe von einem Schnitt Rüssel 8, und das Volumen Verschiebung (Perfusion), in der Salzlösung in die membranöse necklike Region zwischen dem Kopf und Thorax (dh, Gebärmutterhals) und der perfundierten Hämolymphe gesammelt injiziert aus einem zerrissenen Öffnung in einem distalen Bereich des Bauches 9, 10. Diese Techniken sind jedoch durch eine geringe Erholung der Blutzellen und mögliche Verunreinigungen durch Fett Körperzellen bzw. 11 begrenzt. In jüngerer Zeit eine Methode bezeichnet als hohe Einspritzdruck / Recovery verbesserte Rückgewinnung von Immunzellen durch die Verwendung von gerinnungshemmenden Puffer bei gleichzeitiger Reduzierung Ebenen kontaminierender Skalen und inneren Geweben 11. Während diese Methode ermöglicht ein verbessertes Verfahren zur Sammlung und Aufbewahrung Blutzellen für Primär-Kultur, bringt es eine Reihe von Einspritzung und Sammeln Schritte, die nicht notwendig sind, wenn der nachgeschaltete Ziel ist es, zu sammeln, zu fixieren und färben Blutzellen für die Diagnostik. Hier zeigen wir unsere Methode der Erhebung Moskito Hämolymphe, dass die Einfachheit der Durchblutung kombiniert mit gerinnungshemmenden Pufferlösungen anstelle von Kochsalzlösung, mit der Genauigkeit der hohe Einspritzdruck Techniken zur sauberen Vorbereitung der Blutzellen in Aedes Moskitos zu isolieren.

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

Eine vereinfachte, aber genaue Methode zu sammeln und zu färben Mücke Blutzellen beschrieben. Unsere Methode kombiniert die Einfachheit der Perfusion mit der Genauigkeit der hohe Einspritzdruck Techniken zur sauberen Vorbereitung der Blutzellen in Aedes Moskitos zu isolieren. Diese Methode erleichtert Studien erfordern Kenntnisse über die Arten von Blutzellen und deren Hülle und Fülle.

Ein Protokoll für die Erfassung und Färbung Blutzellen aus dem Gelbfiebermücke 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

15.3K Aufrufe.  University of Richmond. Eine vereinfachte, aber genaue Methode zu sammeln und zu färben Mücke Blutzellen beschrieben. Unsere Methode kombiniert die Einfachheit der Perfusion mit der Genauigkeit der hohe Einspritzdruck Techniken zur sauberen Vorbereitung der Blutzellen in Aedes Moskitos zu isolieren. Diese Methode erleichtert Studien erfordern Kenntnisse über die Arten von Blutzellen und deren Hülle und Fülle.

Serie: 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.

Protokoll für die Herstellung eines genetischen Kreuz der Nager Malaria-Erregern

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

Forschung

Immunologie und Infektion

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.

Ein Calcium Biolumineszenzassay für die funktionelle Analyse von Mosquito ( Aedes aegypti) Und Tick ( Rhipicephalus microplus) G-Protein gekoppelten Rezeptoren

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.

A Simple Chelex Protokoll zur DNA-Extraktion aus<em&gt; Anopheles</em&gt; Spp.

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

Utilization of Capsules for Negative Staining of Viral Samples within Biocontainment

Transmission electron microscopy (TEM) is used to observe the ultrastructure of viruses and other microbial pathogens with nanometer resolution. Most biological materials do not contain dense elements capable of scattering electrons to create an image; therefore, a negative stain, which places dense heavy metal salts around the sample, is required. In order to visualize viruses in suspension under the TEM they must be applied to small grids coated with a transparent surface only nanometers thick. Due to their small size and fragility, these grids are difficult to handle and easily moved by air currents. The thin surface is easily damaged, leaving the sample difficult or impossible to image. Infectious viruses must be handled in a biosafety cabinet (BSC) and some require a biocontainment laboratory environment. Staining viruses in biosafety levels (BSL)-3 and -4 is especially challenging because these environments are more turbulent and technicians are required to wear personal protective equipment (PPE), which decreases dexterity. 
In this study, we evaluated a new device to assist in negative staining viruses in biocontainment. The device is a capsule that works as a specialized pipette tip. Once grids are loaded into the capsule, the user simply aspirates reagents into the capsule to deliver the virus and stains to the encapsulated grid, thus eliminating user handling of grids. Although this technique was designed specifically for use in BSL-3 or -4 biocontainment, it can ease sample preparation in any lab environment by enabling easy negative staining of virus. This same method can also be applied to prepare negative stained TEM specimens of nanoparticles, macromolecules and similar specimens.

This protocol provides instruction for negative staining virus samples which can easily be used in BSL-2, -3, or -4 laboratories. It includes the use of an innovative processing capsule, which protects the transmission electron microscopy grid and provides the user easier handling in the more turbulent environments within biocontainment.

Verwendung von Kapseln zur Negativfärbung von Virusproben im Biocontainment

Transmission electron microscopy (TEM) is used to observe the ultrastructure of viruses and other microbial pathogens with nanometer resolution. Most ...

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.

Extraktion von Hemocytes aus Drosophila Melanogaster Larven für mikrobielle Infektionen und Analyse

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 Färbung Blutgefäße und Nervenfasern im Fettgewebe

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.

In Vitro ELISA-Test zur Bewertung der Wirksamkeit von Tollwut-Impfstoffen

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.

Vektorkompetenzanalysen an Aedes aegypti Mücken mit Zika-Virus

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.

Ausbreitung des mikrosporiden Parasiten 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 ...

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.

Fütterung und Quantifizierung von Tierblut und künstlichen Mahlzeiten 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 ...

Methods Article

Ein Protokoll für die Erfassung und Färbung Blutzellen aus dem Gelbfiebermücke Aedes aegypti