Name: in vitro three-dimensional sprouting assay of angiogenesis using mouse embryonic stem cells for vascular disease modeling and drug testing
Uploaded: 2021-05-11T14:30:00
Description: Watch this Scientific Journal Video about In Vitro Three-Dimensional Sprouting Assay of Angiogenesis Using Mouse Embryonic Stem Cells for Vascular Disease Modeling and Drug Testing at JoVE.com

This work was supported by grants from the Nederlandse organisatie voor gezondheidsonderzoek en zorginnovatie (ZonMW 446002501), Health Holland (LSHM19057-H040), Leading Fellows Programme Marie Sk&#322;odowska-Curie COFUND, and by the Association Maladie de Rendu-Osler (AMRO).

1. Media preparation and culture of mESC
<ol>
	<li>Prepare conditioned medium +/- (CM+/-) using the supplement 1x Glasgow MEM (G-MEM BHK-21) medium with 10% (vol/vol) heat-inactivated Fetal Bovine Serum (FBS), 0.05 mM &#946;-mercaptoethanol, 1x non-essential amino acids (NEAA 1x), 2 mM L-glutamine, and 1 mM sodium pyruvate.</li>
	<li>Prepare conditioned medium +/+ (CM+/+) using the supplement CM+/- medium with Leukemia Inhibitory Factor (LIF) (1,500 U/mL) and 0.1 mM &#946;-mercaptoethanol.</li>
	<li>Prepare conditioned...

<ol>
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This protocol describes an unbiased, robust, and reproducible 3D EB-based vascular sprouting assay that is amenable to screening for drugs and genes modulating angiogenesis. This method offers advantages over many widely used two dimensional (2D) assays using endothelial cell cultures such as Human Umbilical Vein Endothelial Cells (HUVECs) to monitor migration (lateral scratch assay or the Boyden chamber assay)22,23&#160;or proliferation (counting cell number, de...

In the past three decades, target-based drug discovery (TDD) has been widely employed in drug discovery by the pharmaceutical industry. TDD incorporates a defined molecular target playing an important role in a disease and relies on the development of relatively simple cell culture systems and readouts for drug screening1. Most typical disease models used in TDD programs include traditional cell culture methods such as cancer cells or immortalized cell lines grown within artificial environments and non-physiological substrates. Although many of these models have provided viable tools for identifying successful drug candidates, the use of such systems can be questionable owing to their poor disease relevance2.
For most diseases, the underlying mechanisms are indeed complex and various cell types, independent signaling pathways, and multiple sets of genes are often found to contribute to a specific disease phenotype. This is also true for inherited diseases where the primary cause is a mutation in one single gene. With the recent advent of human induced pluripotent stem cell (iPSC) technologies and gene editing tools, it is now possible to generate 3D organoids and organ-on-chip disease models that could better recapitulate the in vivo human complexity3,4. The development of such technologies is associated with a resurgence in interest in phenotypic drug discovery (PDD) programs1. PDD can be compared to empirical screening, as they do not rely on knowledge of the identity of a specific drug target or a hypothesis about its role in disease. The PDD approach is now increasingly recognized to strongly contribute to the discovery of first-in-class drugs5. Because the development of human organoid and organ-on-chip technologies is still in its infancy, it is expected that iPSC models (complemented with innovative imaging and machine-learning tools6,7) will provide, in the near future, multiple novel complex cell-based disease models for drug screening and associated PDD programs to overcome the poor productivity of the TDD approach8,9.
While human organoid and organ-on-chip models can provide important insights into disease complexity and to the identification of novel drugs, bringing drugs into new clinical practice also strongly relies on data from animal models to assess their efficacy and safety. Among them, genetically modified mice are certainly the most preferred mammalian models. They have many advantages as they have a relatively short generation time for mammals, have many similar phenotypes to human diseases, and can be easily genetically manipulated. They are therefore extensively used in drug discovery programs10. However, bridging the gap between mice and humans remains an important challenge11. The development of in vitro mouse models equivalent to human organoid and organ-on-chip models could at least partially fill this gap as it will allow direct drug efficacy and safety comparisons between in vivo mouse and in vitro human data.
Here, a vascular sprouting assay in mouse embryoid bodies (EBs) is described. Blood vessels are composed of endothelial cells (inner lining of vessel walls), mural cells (vascular smooth muscle cells&#160;and pericytes)12. This protocol is based on the differentiation of mouse embryonic stem cells (mESCs) into vascularized EBs using hanging droplets that recapitulate de novo endothelial cell and mural cell differentiation13,14. Mouse ESCs can be easily established in culture from isolated day 3.5 mouse blastocysts having different genetic backgrounds15. They also provide possibilities for clonal analysis, lineage tracing, and can be easily genetically manipulated to generate disease models13,16.
As blood vessels nourish all organs, it is not surprising that many diseases if not all, are associated with changes in the microvasculature. In pathological conditions, endothelial cells can adopt an activated state or can become dysfunctional resulting in mural cell death or migration away from blood vessels. These can result in excessive angiogenesis or in vessel rarefaction, can induce abnormal blood flow and defective blood vessel barrier leading to immune cell extravasation, and inflammation12,17,18,19. Research for the development of drugs modulating blood vessels is, therefore&#160;high, and multiple molecular players and concepts have already been identified for therapeutic targeting. In this context, the protocol described is particularly suitable for building disease models and for drug testing as it recapitulates key features of in vivo sprouting angiogenesis, including endothelial tip and stalk cell selection, endothelial cell migration and proliferation, endothelial cell guidance, tube formation, and mural cell recruitment. It also shows similarities with recently described 3D vascular assays based on human iPSC technologies20.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>2-mercaptoethanol</td>
			<td>Milipore, Merck</td>
			<td>805740</td>
			<td>Biohazard: adequate safety instructions should be taken when handling</td>
		</tr>
		<tr>
			<td>Agar Noble</td>
			<td>Difco, BD Pharmigen</td>
			<td>214220</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa Fluo 555 goat anti rat IgG</td>
			<td>Life technologies</td>
			<td>A21434</td>
			<td></td>
		</tr>
		<tr>
			<td>APC conjugated rat anti-mouse PECAM-1 antibody (clone MEC13.3)</td>
			<td>BD Biosciences</td>
			<td>551262</td>
			<td></td>
		</tr>
		<tr>
			<td>APC Rat IgG2a &#954; Isotype Control (Clone&#160; R35-95)</td>
			<td>BD Biosciences</td>
			<td>553932</td>
			<td></td>
		</tr>
		<tr>
			<td>Axiovert 25 inverted phase contrast tissue culture microscope</td>
			<td>ZEISS</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Basic Fibroblast Growth Factor-2 (bFGF)</td>
			<td>Peprotech</td>
			<td>450-33</td>
			<td></td>
		</tr>
		<tr>
			<td>Benchtop Centrifuge, Allegra X-15R</td>
			<td>Beckman Coulter</td>
			<td>392932</td>
			<td></td>
		</tr>
		<tr>
			<td>Biosafety cabinet BioVanguard (Green Line)</td>
			<td>Telstar</td>
			<td>133H401001</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin (BSA)</td>
			<td>Sigma-Aldrich</td>
			<td>A9418</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell counting chamber, Buerker, 0.100mm</td>
			<td>Marienfeld</td>
			<td>640211</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture dishes 60 x 15mm</td>
			<td>Corning</td>
			<td>353802</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture dishes, 35 x 10 mm</td>
			<td>Corning</td>
			<td>353801</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture plates 12-well</td>
			<td>Corning</td>
			<td>3512</td>
			<td></td>
		</tr>
		<tr>
			<td>CFX96 Touch Real-Time PCR Detection System</td>
			<td>Biorad</td>
			<td>1855196</td>
			<td></td>
		</tr>
		<tr>
			<td>Chicken serum</td>
			<td>Sigma-Aldrich</td>
			<td>C5405</td>
			<td></td>
		</tr>
		<tr>
			<td>CHIR-99021 (CT99021) HCl</td>
			<td>Selleckchem</td>
			<td>S2924</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagen I, High Concentration, Rat Tail, 100mg</td>
			<td>Corning</td>
			<td>354249</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase A</td>
			<td>Roche</td>
			<td>10103586001</td>
			<td></td>
		</tr>
		<tr>
			<td>Confocal Laser Scanning Microscope, TCS SP5</td>
			<td>Leica</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Cover glasses, 24 &#215; 50 mm</td>
			<td>Vwr</td>
			<td>631-0146</td>
			<td></td>
		</tr>
		<tr>
			<td>DAPT &#947;&#8209;secretase inhibitor</td>
			<td>Sigma Aldrich</td>
			<td>D5942</td>
			<td></td>
		</tr>
		<tr>
			<td>DC101 anti mouse VEGFR-2 Clone</td>
			<td>BioXcell</td>
			<td>BP0060</td>
			<td></td>
		</tr>
		<tr>
			<td>DC101 isotype rat IgG1</td>
			<td>BioXcell</td>
			<td>BP0290</td>
			<td></td>
		</tr>
		<tr>
			<td>Dimethyl sulfoxide (DMSO)</td>
			<td>Sigma-Aldrich</td>
			<td>D2438-5X</td>
			<td>Biohazard: adequate safety instructions should be taken when handling</td>
		</tr>
		<tr>
			<td>DPBS (10x), no calcium, no magnesium</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>14200067</td>
			<td></td>
		</tr>
		<tr>
			<td>EDTA 40 mM</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>15575-038</td>
			<td></td>
		</tr>
		<tr>
			<td>Embryonic stem-cell Fetal Bovine Serum</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>16141-079</td>
			<td>Should be lot-tested for maximum ES cell viability and growth. Heat inactivate at 60&#176;C and store at &#8722;20 &#176;C for up to 1 year</td>
		</tr>
		<tr>
			<td>Eppendorf Microcentrifuge 5415R</td>
			<td>Eppendorf AG</td>
			<td>&#160;Z605212</td>
			<td></td>
		</tr>
		<tr>
			<td>Erythropoietin, human (hEPO), 250 U (2.5 &#181;g) (1 mL)</td>
			<td>Roche</td>
			<td>11120166001</td>
			<td></td>
		</tr>
		<tr>
			<td>ESGRO Recombinant Mouse LIF Protein (10&#8311; units&#160;&#160;1 mL)</td>
			<td>Milipore, Merck</td>
			<td>ESG1107</td>
			<td></td>
		</tr>
		<tr>
			<td>Falcon tubes 15 mL</td>
			<td>Greiner Bio-One</td>
			<td>188271</td>
			<td></td>
		</tr>
		<tr>
			<td>Falcon tubes 50 mL</td>
			<td>Greiner Bio-0ne</td>
			<td>227270</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter tip ,clear ,sterile F.Gilson, P-200</td>
			<td>Greiner Bio-One</td>
			<td>739288</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter tip ,clear ,sterile F.Gilson, P10</td>
			<td>Greiner Bio-One</td>
			<td>771288</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter tip ,clear ,sterile F.Gilson, P1000</td>
			<td>Greiner Bio-One</td>
			<td>740288</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC conjugated anti-&#945; Smooth Muscle Actin (SMA) (clone 1A4)</td>
			<td>Sigma Aldrich</td>
			<td>F3777</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC conjugated rat anti-mouse CD45 (clone 30-F11)</td>
			<td>Biolegend</td>
			<td>103107</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC Rat IgG2b, &#954; Isotype Ctrl Antibody (clone RTK4530)</td>
			<td>Biolegend</td>
			<td>400605</td>
			<td></td>
		</tr>
		<tr>
			<td>Fluorscent mounting media</td>
			<td>DAKO</td>
			<td>S3023</td>
			<td></td>
		</tr>
		<tr>
			<td>Gascompress</td>
			<td>Cutisoft</td>
			<td>45846</td>
			<td></td>
		</tr>
		<tr>
			<td>Gauze Cutisoft 10 x 10 cm</td>
			<td>Bsn Medical</td>
			<td>45844_00</td>
			<td></td>
		</tr>
		<tr>
			<td>Gel blotting paper, Grade GB003</td>
			<td>Whatman</td>
			<td>WHA10547922</td>
			<td></td>
		</tr>
		<tr>
			<td>Gelatin solution, type B</td>
			<td>Sigma-Aldrich</td>
			<td>G1393-100 ml</td>
			<td></td>
		</tr>
		<tr>
			<td>Glasgow&#39;s MEM (GMEM)</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>21710082</td>
			<td></td>
		</tr>
		<tr>
			<td>IHC Zinc Fixative</td>
			<td>BD Pharmigen</td>
			<td>550523</td>
			<td></td>
		</tr>
		<tr>
			<td>IncuSafe CO2 Incubator</td>
			<td>PHCBi</td>
			<td>MCO-170AICUV-PE</td>
			<td></td>
		</tr>
		<tr>
			<td>Interleukin-6, human (hIL-6)</td>
			<td>Roche</td>
			<td>11138600001</td>
			<td></td>
		</tr>
		<tr>
			<td>L-Glutamine 200 mM</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>25030-024</td>
			<td></td>
		</tr>
		<tr>
			<td>MEM Non-Essential Amino Acids Solution (100x)</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>11140035</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope slide box</td>
			<td>Kartell Labware</td>
			<td>278</td>
			<td></td>
		</tr>
		<tr>
			<td>Microscope slide, Starfrost</td>
			<td>Knittel glass</td>
			<td>VS113711FKB.0</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Cdh5_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00110467</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Eng_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00148981</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Epha4_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00093576</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Ephb2_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00154014</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Flt1_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00096292</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Flt4_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00099064</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Gapdh_3_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT01658692</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Kdr_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00097020</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Notch1_1_SG QuantiTect Primer</td>
			<td>Qiagen</td>
			<td>QT00156982</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Nr2f2_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00153104</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Pecam1_1_SG QuantiTect Primer</td>
			<td>Qiagen</td>
			<td>QT01052044</td>
			<td></td>
		</tr>
		<tr>
			<td>Mm_Tek_1_SG QuantiTect Primer Assay</td>
			<td>Qiagen</td>
			<td>QT00114576</td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse (ICR) Inactivated Embryonic Fibroblasts&#160; (2 M)</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>A24903</td>
			<td>Store vials in liquid nitrogen (195.79 &#176;C) indefinitely</td>
		</tr>
		<tr>
			<td>Mouse embryonic stem cell line 7AC5/EYFP (ATCC SCRC-1033)</td>
			<td>ATCC</td>
			<td>SCRC-1033</td>
			<td>Generated by Dr A Nagy, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Ave, Toronto, Ontario, M5G 1X5, Canada. [Hadjantonakis, A. K., et al. Mechanisms of Development. 76 (1&#8211;2), 79&#8211;90 (1998)].</td>
		</tr>
		<tr>
			<td>Mouse embryonic stem cell lines Acvrl1 +/- and Acvrl1 +/+</td>
			<td></td>
			<td></td>
			<td>Generated at Leiden University Medical Centre [Thalgott, J.H. et al. Circulation. 138 (23), 2698&#8211;2712 (2018)].</td>
		</tr>
		<tr>
			<td>Mouse embryonic stem cells line E14</td>
			<td></td>
			<td></td>
			<td>Provided by M Letarte laboratory and generated according to Cho, S. K., et al. Blood. 98 (13), 3635&#8211;3642 (2001).</td>
		</tr>
		<tr>
			<td>Mouse embryonic stem cells line R1 (ATCC SCRC-1011)</td>
			<td>ATCC</td>
			<td>SCRC-1011</td>
			<td>Generated by Dr A Nagy, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Ave, Toronto, Ontario, M5G 1X5, Canada. [Nagy, A., et al. Procedings of the National Academy of Sciences of the United States of America. 90 (18), 8424&#8211;8428 (1993)].</td>
		</tr>
		<tr>
			<td>Mouse embryonic stem cells line Z/Red (strain 129/Ola)</td>
			<td></td>
			<td></td>
			<td>Generated by Dr A Nagy, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Ave, Toronto, Ontario, M5G 1X5, Canada [Vintersten, K., et al. Genesis. 40 (4), 241&#8211;246 (2004)].</td>
		</tr>
		<tr>
			<td>NanoDrop 1000 UV/VIS Spectrophotometer</td>
			<td>Thermo Fischer Scientific</td>
			<td>ND-1000</td>
			<td></td>
		</tr>
		<tr>
			<td>PD0325901</td>
			<td>Selleckchem</td>
			<td>S1036</td>
			<td></td>
		</tr>
		<tr>
			<td>PDGF-BB, Recombinant Human</td>
			<td>Peprotech</td>
			<td>100-14B</td>
			<td></td>
		</tr>
		<tr>
			<td>Pecam-1 antibody, Rat Anti-Mouse</td>
			<td>BD Biosciences</td>
			<td>550274</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-streptomycin (10,000 U/mL)</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>15140122</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dish, PS, 94/16 mm, standard ,with vents, sterile</td>
			<td>Greiner Bio-One</td>
			<td>633181</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipetboy acu 2</td>
			<td>Integra-Biosciences</td>
			<td>155 019</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipetman G Multichannel P8 x 200G</td>
			<td>Gilson</td>
			<td>F144072</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipetman G Starter Kit, 4 Pipette Kit, P2G, P20G, P200G, P1000G</td>
			<td>Gilson</td>
			<td>F167360</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant Human BMP-4 Protein</td>
			<td>R&#38;D Systems</td>
			<td>314-BP</td>
			<td></td>
		</tr>
		<tr>
			<td>RNeasy Plus mini Kit</td>
			<td>QIAGEN</td>
			<td>74134</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipettes, 10 mL</td>
			<td>Greiner Bio-One</td>
			<td>607 180</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipettes, 25 mL</td>
			<td>Greiner Bio-One</td>
			<td>760 180</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological pipettes, 5 mL</td>
			<td>Greiner Bio-One</td>
			<td>606 180</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium hydroxide (NaOH)</td>
			<td>Merck</td>
			<td>106498</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium pyruvate 100 mM</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>11360039</td>
			<td></td>
		</tr>
		<tr>
			<td>Test tubes 5ml round-bottom with cell-strainer cap</td>
			<td>Corning</td>
			<td>352235</td>
			<td></td>
		</tr>
		<tr>
			<td>Thermal cycler, T100</td>
			<td>Biorad</td>
			<td>1861096</td>
			<td></td>
		</tr>
		<tr>
			<td>Triton X-100 (BioXtra)</td>
			<td>Sigma Aldrich</td>
			<td>T9284</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue Solution, 0.4%</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>15250061</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin (2.5%)</td>
			<td>Gibco, Thermofisher scientific</td>
			<td>15090046</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum Filter/Storage Bottle System, 500 mL</td>
			<td>Corning</td>
			<td>430758</td>
			<td></td>
		</tr>
		<tr>
			<td>VEGFA165 , recombinant murine</td>
			<td>Peprotech</td>
			<td>450-32</td>
			<td></td>
		</tr>
		<tr>
			<td>Water, Sterile</td>
			<td>Fresenius-Kabi</td>
			<td>B230531</td>
			<td></td>
		</tr>
		<tr>
			<td>Waterbath, Lab-Line Digital</td>
			<td>Thermo Fischer Scientific</td>
			<td>18052A</td>
			<td></td>
		</tr>
	</tbody>
</table>

in vitro three-dimensional sprouting assay of angiogenesis using mouse embryonic stem cells for vascular disease modeling and drug testing

Recent advances in induced pluripotent stem cells (iPSC) and gene editing technologies enable the development of novel human cell-based disease models for phenotypic drug discovery (PDD) programs. Although these novel devices could predict the safety and efficacy of investigational drugs in humans more accurately, their development to the clinic still strongly rely on mammalian data, notably the use of mouse disease models. In parallel to human organoid or organ-on-chip disease models, the development of relevant in vitro mouse models is therefore an unmet need for evaluating direct drug efficacy and safety comparisons between species and in vivo and in vitro conditions. Here, a vascular sprouting assay that utilizes mouse embryonic stem cells differentiated into embryoid bodies (EBs) is described. Vascularized EBs cultured onto 3D-collagen gel develop new blood vessels that expand, a process called sprouting angiogenesis. This model recapitulates key features of in vivo sprouting angiogenesis-formation of blood vessels from a pre-existing vascular network-including endothelial tip cell selection, endothelial cell migration and proliferation, cell guidance, tube formation, and mural cell recruitment. It is amenable to screening for drugs and genes modulating angiogenesis and shows similarities with recently described three-dimensional (3D) vascular assays based on human iPSC technologies.

The protocol overview of the blood vessel sprouting assay is shown in Figure 1. Nine-day-old EBs derived from three independent 129/Ola mESC lines (Z/Red, R1, and E14) were enzymatically dissociated into single cells using collagenase A. Cells were stained for PECAM-1 and analyzed by Fluorescence-activated cell sorting (FACS) as described. All the cell lines exhibited robust endothelial differentiation, and no differences in their ability to differentiate into endothelial cells were observed...

Watch this Scientific Journal Video about In Vitro Three-Dimensional Sprouting Assay of Angiogenesis Using Mouse Embryonic Stem Cells for Vascular Disease Modeling and Drug Testing at JoVE.com

In Vitro Three-Dimensional Sprouting Assay of Angiogenesis Using Mouse Embryonic Stem Cells for Vascular Disease Modeling and Drug Testing

This assay utilizes mouse embryonic stem cells differentiated into embryoid bodies cultured in 3D-collagen gel to analyze the biological processes that control sprouting angiogenesis in vitro. The technique can be applied for testing drugs, modeling diseases, and for studying specific genes in the context of deletions that are embryonically lethal.

In Vitro Three-Dimensional Sprouting Assay of Angiogenesis Using Mouse Embryonic Stem Cells for Vascular Disease Modeling and Drug Testing

Recent advances in induced pluripotent stem cells (iPSC) and gene editing technologies enable the development of novel human cell-based disease models for ...

Research

JoVE Journal

Biology

In vitro Differentiation of Mouse Embryonic Stem (mES) Cells Using the Hanging Drop Method

In vitro Differentiation of Mouse Embryonic Stem mES Cells Using the Hanging Drop Method

Stem cells have the remarkable potential to develop into many different cell types. When a stem cell divides, each new cell has the potential to either ...

In vitro Labeling of Human Embryonic Stem Cells for Magnetic Resonance Imaging

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Efficient Differentiation of Mouse Embryonic Stem Cells into Motor Neurons

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In general, human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs)1 can be cultured under variable conditions. However, it ...

Endothelial Cell Tube Formation Assay for the In Vitro Study of Angiogenesis

Endothelial Cell Tube Formation Assay for the In Vitro Study of Angiogenesis

Angiogenesis is a vital process for normal tissue development and wound healing, but is also associated with a variety of pathological conditions. Using ...

Profiling Individual Human Embryonic Stem Cells by Quantitative RT-PCR

Heterogeneity of stem cell population hampers detailed understanding of stem cell biology, such as their differentiation propensity toward different ...

Zinc-finger Nuclease Enhanced Gene Targeting in Human Embryonic Stem Cells

One major limitation with current human embryonic stem cell (ESC) differentiation protocols is the generation of heterogeneous cell ...

Isolation and Primary Culture of Mouse Aortic Endothelial Cells

The vascular endothelium is essential to normal vascular homeostasis. Its dysfunction participates in various cardiovascular disorders. The mouse is an ...

Three-dimensional Reconstruction of the Vascular Architecture of the Passive CLARITY-cleared Mouse Ovary

The ovary is the main organ of the female reproductive system and is essential for the production of female gametes and for controlling the endocrine ...