Name: visualization and quantitative analysis of embryonic angiogenesis in xenopus tropicalis
Uploaded: 2017-05-25T14:00:00
Description: Watch this Scientific Journal Video about Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis at JoVE.com

Denne undersøgelse blev inspireret af Levine et al. , Som beskrev denne eksperimentelle metode og gav en omfattende beskrivelse af vaskulær udvikling i Xenopus laevis. Vi takker medlemmerne af vores laboratorium for deres input. Denne undersøgelse blev støttet af Yonsei Universitets Fremtidsforskningsinitiativ fra 2015 (2015-22- 0095) og Biofysisk Udviklingsprogram for National Research Foundation (NRF) finansieret af ministeriet for videnskab, IKT og fremtidig planlægning ( NRF-2013M3A9D5072551)

Alle eksperimenter overholdt protokoller godkendt af Yonsei University College of Medicine Institutionelle Dyrepleje og Brugskomitéer. 1. Fremstilling af xenopus tropicalis embryoer BEMÆRK: Xenopus tropicalis-embryoner blev fremstillet som tidligere beskrevet 10 med let modifikation. Xenopus tropicalis-embryoner blev iscenesat ifølge tabellerne i Nieuwkoop og Faber 11 . <ol><li> Induktion af ægl?...

<ol>
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Protokollen, der præsenteres her, blev først udviklet af Ali H. Brivanlou og kolleger til at undersøge udviklingshændelser under vaskulær dannelse i Xenopus laevis 4 , men som det fremgår af dette manuskript, kan det anvendes til andre små dyr. Farveinjektion i hjertet er let at udføre, og hele det vaskulære netværk kan afbildes under et fluorescensdissektionsmikroskop, såvel som et konfokalt mikroskop. Hvis farvestoffet injiceres i hjertet under skibets udvikling, kan dynamik...

Vasculogenese, dannelsen af ​​nye blodkar fra nyfødte endotelceller og angiogenese, dannelsen af ​​nye fartøjer fra eksisterende skibe, er to forskellige processer, der former embryonisk vaskulatur 1 . Enhver dysregulering i disse processer resulterer i forskellige hjertesygdomme og strukturelle abnormiteter af fartøjer. Endvidere er tumorvækst forbundet med ukontrolleret karvestigning. Som sådan er molekylære mekanismer, der ligger til grund for vaskulogenese og angiogenese, genstand for intens undersøgelse 2 . Xenopus og zebrafisk er attraktive hvirveldyrsmodeller til vaskulogenese og angiogeneseundersøgelser af flere årsager. For det første er deres embryoner små; Derfor er det relativt nemt at se hele vaskulaturen. For det andet er embryonal udvikling hurtig; Det tager kun et par dage for hele vaskulaturen at udvikle, i hvilket tidsrum den udviklende vaskul<html> Ature kan afbildes. For det tredje er genetiske og farmakologiske interventioner før og under karretdannelse nemme at udføre, såsom gennem mikroinjektion af antisense morpholino nukleotider (MOs) i det udviklende embryo eller gennem badapplikationen af ​​lægemidler 3 , 4 , 5 . Den unikke fordel ved Xenopus over zebrafisk er, at embryologiske manipulationer kan udføres, fordi Xenopus følger stereotypiske holoblastiske spaltninger, og det embryonske skæbnekort er veldefineret 6 . For eksempel er det muligt at generere et embryo, hvor kun en lateral side er genetisk manipuleret ved at indsprøjte en antisense MO til en celle i tocellefasen. Det er også muligt at transplantere hjertet primordium fra ét embryo til et andet for at bestemme, om genet udøver sin funktion ved hjælp af en celle-iboende eller -ekstruktiv mekanismeAss = &quot;xref&quot;&gt; 7. Selvom disse teknikker hovedsagelig er blevet udviklet i Xenopus laevis , som er allotetraploid og derfor ikke er ideel til genetiske undersøgelser, kan de anvendes direkte til Xenopus tropicalis , en nært beslægtet diploid art 8 . En måde at visualisere vaskulaturet på i et levende Xenopus embryo er at injicere et fluorescerende farvestof til at mærke blodkarrene. Acetyleret lavdensitetslipoprotein (AcLDL) mærket med et fluorescerende molekyle, såsom DiI, er en meget nyttig probe. I modsætning til ikke-acetyleret LDL binder AcLDL ikke til LDL-receptoren 9, men endocytteres af makrofager og endotelceller. Injektionen af ​​DiI-AcLDL i hjertet af et levende dyr resulterer i den specifikke fluorescerende mærkning af endotelceller, og hele vaskulaturen kan afbildes ved fluorescensmikroskopi i levende eller faste embryoner 4 . Her præsiderer viEnt detaljerede protokoller til visualisering og kvantificering af blodkar ved anvendelse af DiI-AcLDL i Xenopus tropicalis ( Figur 1 ). Vi giver nøgle praktiske punkter, med eksempler på succesfulde og mislykkede forsøg. Derudover giver vi en retfærdig metode til kvantitativ analyse af vaskulær kompleksitet, hvilket kan være nyttigt ved vurdering af virkningerne af genetiske og miljømæssige faktorer ved udformningen af ​​det vaskulære netværk.

<table border="0" cellpadding="0" cellspacing="0" width="539">
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	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">35mm Petri dish</td>
			<td style="width:113px;">SPL</td>
			<td style="width:93px;">10035</td>
			<td style="width:180px;">Sylgard mold frame</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">60mm Petri dish</td>
			<td style="width:113px;">SPL</td>
			<td style="width:93px;">10060</td>
			<td>Embryo raising tray</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Borosilicate Glass</td>
			<td style="width:113px;">Sutter instrument</td>
			<td style="width:93px;">B100-50-10</td>
			<td>Needle for injection</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">BSA</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">A3059-10G</td>
			<td>Coating reagent</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">CaCl2</td>
			<td style="width:113px;">D.S.P.GR Reagent</td>
			<td style="width:93px;"></td>
			<td>0.1X MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Coverslip</td>
			<td style="width:113px;">Superior</td>
			<td style="width:93px;">HSU-0111520</td>
			<td>For confocal imaging</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">DiI-AcLDL</td>
			<td style="width:113px;">Thermo Fisher Scientific</td>
			<td style="width:93px;">L3484</td>
			<td>Vessel staining solution</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">FBS</td>
			<td style="width:113px;">Hyclone</td>
			<td style="width:93px;">SH.30919.02</td>
			<td>For storage of testis</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Fiber Optical Illuminator</td>
			<td style="width:113px;">World Precision Instruments</td>
			<td style="width:93px;">Z-LITE-Z</td>
			<td>Light</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Ficoll</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">F4375</td>
			<td>Injection buffer</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Flaming/Brown Micropipette Puller</td>
			<td style="width:113px;">Sutter instrument</td>
			<td style="width:93px;">P-97</td>
			<td>Injection needle puller</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Forcep</td>
			<td style="width:113px;">Fine Science Tool</td>
			<td style="width:93px;">11255-20</td>
			<td style="width:180px;">For embryo hatching and 
			needle tip cutting</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Glass Bottom dish</td>
			<td style="width:113px;">SPL</td>
			<td style="width:93px;">100350</td>
			<td>For confocal imaging</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">hCG</td>
			<td style="width:113px;">MNS Korea</td>
			<td style="width:93px;"></td>
			<td>For priming of frogs</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">HEPES</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">H3375</td>
			<td>Buffering agent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Incubator</td>
			<td style="width:113px;">Lab. Companion</td>
			<td style="width:93px;">ILP-02</td>
			<td>For raising embryos</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">KCl</td>
			<td style="width:113px;">DAEJUNG</td>
			<td style="width:93px;">6566-4400</td>
			<td>MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">L15 medium</td>
			<td style="width:113px;">Gibco</td>
			<td style="width:93px;">11415-114</td>
			<td>For storage of testis</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">L-cysteine</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">168149-100G</td>
			<td>De-jellying reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">MgSO4</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">M7506</td>
			<td>MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Microtube</td>
			<td style="width:113px;">Axygen</td>
			<td style="width:93px;">MCT-175-C-S</td>
			<td>For storage of testis</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">MS222</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">E10521</td>
			<td>Anesthetic powder</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">NaCl</td>
			<td style="width:113px;">DAEJUNG</td>
			<td style="width:93px;">7647-14-5</td>
			<td>MBS component</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">NaOH</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">S-0899</td>
			<td>pH adjusting reagent</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Paraformaldehyde</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">P6148</td>
			<td>Fixatives</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">PBS</td>
			<td style="width:113px;">BIOSESANG</td>
			<td style="width:93px;">P2007</td>
			<td>Buffer for imaging</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">pH paper</td>
			<td style="width:113px;">Sigma</td>
			<td style="width:93px;">P4536-100EA</td>
			<td>For confirming pH</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">PICO-LITER INJECTOR</td>
			<td style="width:113px;">Waner instruments</td>
			<td style="width:93px;">PLI-100A</td>
			<td>For injection</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Pin</td>
			<td style="width:113px;">Pinservice</td>
			<td style="width:93px;">26002-10</td>
			<td>For incision</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">Pinholder</td>
			<td style="width:113px;">Scitech Korea</td>
			<td style="width:93px;">26016-12</td>
			<td>For incision</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Precision Stereo Zoom Binocular Microscope</td>
			<td style="width:113px;">World Precision Instruments</td>
			<td style="width:93px;">PZMIII</td>
			<td>For visual screening</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:153px;">Standard Manual Control Micromanipulator&#160;</td>
			<td style="width:113px;">Waner instruments</td>
			<td style="width:93px;">W4 64-0056</td>
			<td>For microinjection</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:153px;">SYLGARD 184 Kit</td>
			<td style="width:113px;">Dow Corning</td>
			<td style="width:93px;"></td>
			<td>For DiI injection</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:153px;">Transfer pipette</td>
			<td style="width:113px;">Korea Ace Scientific Co.</td>
			<td style="width:93px;">YM.B78-400</td>
			<td>For eggs and 
			embryo collection</td>
		</tr>
	</tbody>
</table>

visualization and quantitative analysis of embryonic angiogenesis in xenopus tropicalis

Blodkar leverer ilt og næringsstoffer i hele kroppen, og dannelsen af ​​det vaskulære netværk er under tæt udviklingskontrol. Den effektive in vivo visualisering af blodkar og den pålidelige kvantificering af deres kompleksitet er nøglen til forståelsen af ​​biologi og sygdom i det vaskulære netværk. Her giver vi en detaljeret metode til visualisering af blodkar med et kommercielt tilgængeligt fluorescerende farvestof, humanplasmaacetyleret lavdensitetslipoprotein DiI-kompleks (DiI-AcLDL) og kvantificering af deres kompleksitet i Xenopus tropicalis . Blodkar kan mærkes ved en simpel injektion af DiI-AcLDL ind i et embryos slagende hjerte, og blodkar i hele embryoet kan afbildes i levende eller faste embryoner. Kombineret med genforstyrrelse ved målrettet mikroinjektion af nukleinsyrer og / eller badapplikationen af ​​farmakologiske reagenser kan et gens eller en signalvejsstats rolle på vaskulær udvikling være invektetSteget inden for en uge uden at ty til sofistikerede genetisk manipulerede dyr. På grund af det veldefinerede venesystem af Xenopus og dets stereotype angiogenese kan spiring af allerede eksisterende skibe, fartøjskompleksitet kvantificeres effektivt efter perturbationsforsøg. Denne relativt enkle protokol skal fungere som et let tilgængeligt værktøj inden for forskellige områder inden for kardiovaskulær forskning.

Tidslinje for eksperimenter (figur 1 og 2) Kort efter befrugtning kan målrettet mikroinjektion udføres for at modulere genekspression. For eksempel kan en antisense MO, der specifikt binder til initieringskodonet af det endogene Tie2-mRNA, injiceres, hæmme oversættelsen af ​​Tie2-målmRNA ved sterisk hindring. En MO kan konjugeres til fluorescein til den nemme visuelle screening af vellykkede injicerede embryoner. Alterna...

Watch this Scientific Journal Video about Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis at JoVE.com

Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis

Denne protokol demonstrerer en fluorescensbaseret metode til visualisering af vaskulaturen og kvantificering af dets kompleksitet i Xenopus tropicalis . Blodkar kan billedbehandles minutter efter injektion af et fluorescerende farvestof i et embryos slaghalve efter genetisk og / eller farmakologisk manipulation for at studere kardiovaskulær udvikling in vivo .

Visualisering og kvantitativ analyse af embryonisk angiogenese i<em&gt; Xenopus tropicalis</em

Blood vessels supply oxygen and nutrients throughout the body, and the formation of the vascular network is under tight developmental control. The ...

The overall goal of this procedure is to visualize the vasculature of Xenopus tropicalis tadpoles. This method can help answer key questions in the field of cardiovascular biology such as how angiogenesis is regulated. The main advantage of this technique is that blood vessels in an intact well type embryo can be visualized by a simple fluorescent dye injection.Begin by using a micro loader to fill a tapered glass micro pipette with approximately five microliters of clear diI acetylated LDL solution taking care that no precipitated particles are loaded. Under a dissecting microscope use a fine pair of number 55 forceps to clip the tip of the pipette to adjust the volume of the uploaded complex and set the pressure controlled injection system to eject approximately five nano liters of solution per injection. Then submerge the pipette tip in 0.04%MS-222 in 0.1X modified Barth's saline or MBS in a custom made Sylgard mold.Next transfer Xenopus tropicalis embryo to the Sylgard mold and confirm complete sedation with a lack of response to dorsal fin stimulation. Under the dissecting microscope load the embryo ventral side up into the V shaped indentation of the mold in a slightly oblique position. Tightly fit two 0.1 millimeter minutian pins to a pin holder and use one pin to puncture the skin over the heart which should be visibly pulsing.Insert the pin through the hole in the space between the heart and the skin without puncturing the heart and position the inserted tip within the region where the incision will be made. Then rub the second pin against the inserted pin to make a linear incision and use both pins together to gently widen the incision, exposing the heart. To inject the DiI acetylated LDL solution, insert the glass pipette tip into the heart and inject 50 to 60 nano liters of the DiI acetylated LDL in approximately 10 ejection pulses.When all of the dye solution has been delivered confirm that the heart is still beating and transfer the embryo into a new Petri dish containing 0.1X MBS. After five to 10 minutes the tadpole should recover from anesthesia and begin to move. After an appropriate number of embryos have been injected, visually screen the correctly labeled anesthetized embryos under a fluorescence microscope discarding any animals that have other organs labeled.Embryos that have been insufficiently labeled can be injected again. Then capture images of the correctly labeled embryos. For a more thorough imaging of the blood vessels, fix re anesthetized embryos in 4%paraformaldehyde for one hour at room temperature protected from light for visualization by confocal microscopy.If a sufficient amount of diI acetylated LDL is injected into the heart, the posterior cardinal vein, or PCV, should be immediately visible under a fluorescence microscope. The intersomitic veins, or ISV's, emerge dorsally from the PCV in an anterior to posterior wave beginning at stage 36 and ending around stage 40 to 41 becoming lightly branched around stage 43. The PCV and ISV's grow in a stereotypical angiogenic pattern that is under tight developmental control.Interestingly, the knockdown of TIE-2 signaling by antisense morphalinos decreases the length and the complexity of the ISV's whereas expression of the constitutively active form of TIE-2 induces excessive ISV branching. A Vein Complexity Index can be calculated to assess the complexity of the ISV's and rendered paths can be generated to visualize the overall architecture of the embryonic Xenopus tropicalis vasculature. The original protocol was described for using Xenopus laevis by Levin and Colics and we adapted it for Xenopus tropicalis.Once mastered, this technique can be completed in one hour if it is performed properly. Before this procedure, genetic and pharmacological manipulations can be performed to answer additional questions such as which genes and signaling pathways regulate vascular development. Using this procedure the labeled vasculature can be imaged in an intact animal in real time providing a powerful tool for investigating the dynamics of vascular development.After watching this video you should have a good understanding of how to inject diI acetylated LDL into the heart of a Xenopus tropicalis tadpole to visualize it's vasculature.

Research

JoVE Journal

Developmental Biology

Visualization and Quantitative Analysis of Embryonic Angiogenesis in Xenopus tropicalis

Manipulation and In Vitro Maturation of Xenopus laevis Oocytes, Followed by Intracytoplasmic Sperm Injection, to Study Embryonic Development

Manipulation and In Vitro Maturation of Xenopus laevis Oocytes, Followed by Intracytoplasmic Sperm Injection, to Study Embryonic Development

Manipulation og<em&gt; In vitro</em&gt; Modning af<em&gt; Xenopus laevis</em&gt; Oocytter, efterfulgt af ICSI, for at studere fosterudviklingen

Amphibian eggs have been widely used to study embryonic development. Early embryonic development is driven by maternally stored factors accumulated during ...

Analysis of Cardiomyocyte Development using Immunofluorescence in Embryonic Mouse Heart

Analyse af Cardiomyocyte Development hjælp Immunofluorescens i embryonale Mouse Hjerte

During heart development, the generation of myocardial-specific structural and functional units including sarcomeres, contractile myofibrils, intercalated ...

Visualization of Chondrocyte Intercalation and Directional Proliferation via Zebrabow Clonal Cell Analysis in the Embryonic Meckel&#8217;s Cartilage

Visualisering af Chondrocyt Intercalation og Directional spredning via Zebrabow Klonal Cell Analysis i Embryonale Meckel s Brusk

Development of the vertebrate craniofacial structures requires precise coordination of cell migration, proliferation, adhesion and differentiation. ...

Stem cell-like Xenopus Embryonic Explants to Study Early Neural Developmental Features In Vitro and In Vivo

Stem cell-like Xenopus Embryonic Explants to Study Early Neural Developmental Features In Vitro and In Vivo

Stamcelle-lignende<em&gt; Xenopus</em&gt; Embryonale Eksplantater at studere Tidlig Neural Udviklingsmæssige Egenskaber<em&gt; In vitro</em&gt; Og<em&gt; In vivo</em

Understanding the genetic programs underlying neural development is an important goal of developmental and stem cell biology. In the amphibian blastula, ...

Transcriptome Profiling of In-Vivo Produced Bovine Pre-implantation Embryos Using Two-color Microarray Platform

Transcriptome Profiling of In-Vivo Produced Bovine Pre-implantation Embryos Using Two-color Microarray Platform

Transkriptom profilering<em&gt; In-vivo</em&gt; Produceret Bovine præimplantationsembryoner Brug To farve Microarray Platform

Early embryonic loss is a large contributor to infertility in cattle. Moreover, bovine becomes an interesting model to study human preimplantation embryo ...

Technique to Target Microinjection to the Developing Xenopus Kidney

Technique to Target Microinjection to the Developing Xenopus Kidney

Teknik Target Mikroinjektion til udviklingslandene<em&gt; Xenopus</em&gt; Nyre

The embryonic kidney of Xenopus&#160;laevis (frog), the pronephros, consists of a single nephron, and can be used as a model for kidney disease. Xenopus ...

Analysis of Coronary Vessels in Cleared Embryonic Hearts

Analyse af koronarkar i Cleared Embryonale hjerter

Whole mount visualization of the embryonic coronary plexus from which the capillary and arterial networks will form is rendered problematic using standard ...

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development

Lysmedieret reversibel modulering af den mitogenaktiverede proteinkinasevej under celledifferentiering og<em&gt; Xenopus</em&gt; Embryonudvikling

Kinase activity is crucial for a plethora of cellular functions, including cell proliferation, differentiation, migration, and apoptosis. During early ...

Quantitative Whole-mount Immunofluorescence Analysis of Cardiac Progenitor Populations in Mouse Embryos

Kvantitative hele-mount immunofluorescens analyse af Cardiac stamfader populationer i mus embryoner

The use of ever-advancing imaging techniques has contributed broadly to our increased understanding of embryonic development. Pre-implantation development ...