Diese Arbeit wurde vom NCI R01 CA120659 (RS) unterstützt.

1. Ein Matrigel-Based Rohr Formation Assay zur vaskulären Aktivität von Tumorzellen Beurteilen <ol><li> Vorbereitung der Tumorzellen und mikrovaskulären Endothelzellen: Hirntumor-Zellen wie U87-Zellen, Melanomzellen B16F1, Brustkrebs MDA-MB-435, und die Zellen des Darms HCT116 wurden in DMEM ergänzt mit 10% FBS und Penicillin / Streptomycin (alle von Invitrogen ). Endothelial Zelllinie humanen mikrovaskulären Endothelzellen (HMVECs) wurden in EBM2 Medium (Lonza) mit 1 pg / ml Hydrocortison und 1 ng / ml epidermal growth factor, 10% FBS und Penicillin / Streptomycin kultiviert. Die Zellen wurden mit PBS dreimal gewaschen und getrennt mit 0,05% Trypsin / EDTA (Invitrogen). Nach Zentrifugation mit 2.000 rpm für 5 min wurden Zellpellets erneut mit PBS gewaschen. Dann wurden die pelletierten Zellen mit einer Zählkammer gezählt. </li><li> Matrigel Zubereitung: Ein Aliquot von Wachstumsfaktor-reduzierten Matrigel (BD Bioscience) bis bei Raumtemperatur erwärmt. Bevor vollständig aufgetaut war es auf Eis überführt und seine Flüssigkeit wurde auf Eis für mindestens 10 min gehalten. Dann wurden 50 ul der Matrigel wurde 96-Well-Platten auf horizontaler Ebene, dass die Matrigel gleichmäßig zu verteilen ermöglicht ausplattiert und inkubiert für 30 min bei 37 ° C. </li><li> Rohr Bildung: Cells (1-2 x 10 4) wurden mit serumfreiem DMEM für Tumorzellen oder EBM-2 für Endothelzellen resuspendiert und lud auf der Oberseite des Matrigel. Wenn dieser Test zur Messung der Wirkung von einigen Agenten auf Tubulus Entwicklung verwendet wurde, wurden diese Mittel (Stimulatoren oder Inhibitoren), die Serum-freiem Medium aufgenommen. Jede bedingte Gruppe enthalten 4-6 Brunnen. </li><li> Bild-und Daten-Analyse: Nach der Inkubation bei 37 ° C über Nacht, wurde jede Vertiefung direkt unter dem Mikroskop analysiert. Wenn Tubuli zur Fixierung benötigt wurden, wurden 100 ul 10% igem Formalin Kochsalzlösung-basierte Lösung vorsichtig hinzugefügt und zehn Minuten später war es soweit für die Analyse. Unter einem Mikroskop mit 10x Phasenkontrast, wurden Tubuli in jedes Feld abgebildet und einem Durchschnitt von Tubuli 3 bis 5 zufälligen Feldern in jeder Vertiefung wurde gezählt. </li></ol> 2. Repräsentative Ergebnisse: HMVECs wurden als positive Kontrolle verwendet, da diese Röhren aus klarem längliche Zellkörper, die Polygon-Netzwerk zu bilden verbinden entwickelt wurden. B16F1, U87 und MDA-MB-435 Zellen entwickelt vaskulären Tubuli ähnlich denen von HMVECs gebildet, aber HCT116 Zellen nicht (Abbildung 1). Eine Zelle dosisabhängig tube formation wurde in U87-Zellen getestet. Wie in Abbildung 2 gezeigt, gebildet 10.000 Zellen abgesetzt Tubuli. Sobald die Zellen wurden verdoppelt, war eine solide Gefäßnetz vergleichbar mit denen in HMVECs gesehen. Im Gegensatz dazu konnte Zellen weniger als 5.000 bis eine vaskuläre Phänotyp zu bilden. <img src="/files/ftp_upload/3040/3040fig1.jpg" alt="Abbildung 1"/> Abbildung 1. Rohr-Bildung durch HMVECs, U87, MDA-MB-435 und B16F1 Zellen induziert, aber nicht HCT116-Zellen. Alle Zellen (2 x 10 4) wurden auf Matrigel geladen und über Nacht inkubiert. Tubuli wurden aufgenommen mit Phasenkontrast. HMVECs wurden als positive Kontrolle verwendet. Ein Vertreter von 3-5 Felder zu sehen war. Bar: 100 um. <img src="/files/ftp_upload/3040/3040fig2.jpg" alt="Abbildung 2"/> Abbildung 2. U87-Zell-induzierte Tubuli in einer Zellzahl-abhängigen Weise. Verschiedene Zahlen von U87-Zellen als in den Ecken angegeben wurden tube formation verwendet. HMVECs wurden für eine positive Kontrolle verwendet. Bar: 100 mm.

<ol>
	<li>Shao, R., Guo, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+microvascular+endothelial+cells+immortalized+with+human+telomerase+catalytic+protein:+a+model+for+the+study+of+in+vitro+angiogenesis.">Human microvascular endothelial cells immortalized with human telomerase catalytic protein: a model for the study of in vitro angiogenesis.</a> Biochemical &#38; Biophysical Research Communications. 321, 788-794 (2004).</li><li>Ribeiro, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemostatic+properties+of+the+SV-40+transfected+human+microvascular+endothelial+cell+line+(HMEC-1).+A+representative+in+vitro+model+for+microvascular+endothelium.">Hemostatic properties of the SV-40 transfected human microvascular endothelial cell line (HMEC-1). A representative in vitro model for microvascular endothelium.</a> Thromb Res. 79, 153-1561 (1995).</li><li>Ades, E. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HMEC-1:+establishment+of+an+immortalized+human+microvascular+endothelial+cell+line.">HMEC-1: establishment of an immortalized human microvascular endothelial cell line.</a> J Invest Dermatol. 99, 683-690 (1992).</li><li>Shao, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acquired+expression+of+periostin+by+human+breast+cancers+promotes+tumor+angiogenesis+through+up-regulation+of+vascular+endothelial+growth+factor+receptor+2+expression.">Acquired expression of periostin by human breast cancers promotes tumor angiogenesis through up-regulation of vascular endothelial growth factor receptor 2 expression.</a> Molecular &#38; Cellular Biology. 24, 3992-4003 (2004).</li><li>Shao, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=YKL-40,+a+secreted+glycoprotein,+promotes+tumor+angiogenesis.">YKL-40, a secreted glycoprotein, promotes tumor angiogenesis.</a> Oncogene. 28, 4456-4468 (2009).</li><li>Basu, G. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+role+for+cyclooxygenase-2+in+regulating+vascular+channel+formation+by+human+breast+cancer+cells.">A novel role for cyclooxygenase-2 in regulating vascular channel formation by human breast cancer cells.</a> Breast Cancer Research. 8, R69-R69 (2006).</li><li>Scavelli, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasculogenic+mimicry+by+bone+marrow+macrophages+in+patients+with+multiple+myeloma.">Vasculogenic mimicry by bone marrow macrophages in patients with multiple myeloma.</a> Oncogene. 27, 663-674 (2008).</li><li>El Hallani, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+alternative+mechanism+in+glioblastoma+vascularization:+tubular+vasculogenic+mimicry.">A new alternative mechanism in glioblastoma vascularization: tubular vasculogenic mimicry.</a> Brain. 133, 973-982 (2010).</li><li>Maniotis, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vascular+channel+formation+by+human+melanoma+cells+in+vivo+and+in+vitro:+vasculogenic+mimicry.">Vascular channel formation by human melanoma cells in vivo and in vitro: vasculogenic mimicry.</a> American Journal of Pathology. 155, 739-752 (1999).</li><li>Hendrix, M. J., Seftor, E. A., Hess, A. R., Seftor, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasculogenic+mimicry+and+tumour-cell+plasticity:+lessons+from+melanoma.">Vasculogenic mimicry and tumour-cell plasticity: lessons from melanoma.</a> Nature Reviews Cancer. 3, 411-421 (2003).</li><li>Folberg, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+cell+plasticity+in+uveal+melanoma:+microenvironment+directed+dampening+of+the+invasive+and+metastatic+genotype+and+phenotype+accompanies+the+generation+of+vasculogenic+mimicry+patterns.">Tumor cell plasticity in uveal melanoma: microenvironment directed dampening of the invasive and metastatic genotype and phenotype accompanies the generation of vasculogenic mimicry patterns.</a> American Journal of Pathology. 169, 1376-1389 (2006).</li><li>Liu, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prostate-specific+membrane+antigen+directed+selective+thrombotic+infarction+of+tumors.">Prostate-specific membrane antigen directed selective thrombotic infarction of tumors.</a> Cancer Research. 62, 5470-5475 (2002).</li><li>Sood, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+clinical+significance+of+tumor+cell-lined+vasculature+in+ovarian+carcinoma:+implications+for+anti-vasculogenic+therapy.">The clinical significance of tumor cell-lined vasculature in ovarian carcinoma: implications for anti-vasculogenic therapy.</a> Cancer Biology &#38; Therapy. 1, 661-664 (2002).</li><li>Shirakawa, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemodynamics+in+vasculogenic+mimicry+and+angiogenesis+of+inflammatory+breast+cancer+xenograft.">Hemodynamics in vasculogenic mimicry and angiogenesis of inflammatory breast cancer xenograft.</a> Cancer Research. 62, 560-566 (2002).</li><li>Ruf, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+role+of+tissue+factor+pathway+inhibitors+1+and+2+in+melanoma+vasculogenic+mimicry.">Differential role of tissue factor pathway inhibitors 1 and 2 in melanoma vasculogenic mimicry.</a> Cancer Research. 63, 5381-5389 (2003).</li><li>Seftor, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cooperative+interactions+of+laminin+5+gamma2+chain,+matrix+metalloproteinase-2,+and+membrane+type-1-matrix/metalloproteinase+are+required+for+mimicry+of+embryonic+vasculogenesis+by+aggressive+melanoma.">Cooperative interactions of laminin 5 gamma2 chain, matrix metalloproteinase-2, and membrane type-1-matrix/metalloproteinase are required for mimicry of embryonic vasculogenesis by aggressive melanoma.</a> Cancer Research. 61, 6322-6327 (2001).</li><li>Shirakawa, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vasculogenic+mimicry+and+pseudo-comedo+formation+in+breast+cancer.">Vasculogenic mimicry and pseudo-comedo formation in breast cancer.</a> International Journal of Cancer. 99, 821-828 (2002).</li></ol>

Keine Interessenskonflikte erklärt.

Um für diesen Test erfolgreich zu sein, sollte die Qualität der Matrigel zuerst getestet werden. Eine kleine Probe von BD Bioscience erhalten werden, um Vorlauf der Test unter Verwendung von HMVECs. Verschiedene Produkte können Batch-Display ungleichen Qualitäten, in denen einige viel nicht bieten eine optimale Voraussetzung für tube formation. Zweitens sollten alle Blasen vermieden werden, wenn ein Aliquot von Matrigel in 96-Well-Platten geladen werden, da Blasen Tubulus Bildung stören können. Wenn kleine Bläsc...

<table border="1"><tbody><tr><th> Name des Reagenzes </th><th> Firma </th><th> Katalog-Nummer </th></tr><tr><td> DMEM </td><td> Invitrogen </td><td> 11995 </td></tr><tr><td> FBS </td><td> Invitrogen </td><td> 16000-044 </td></tr><tr><td> Growth factor-reduziert Matrigel </td><td> BD Bioscience </td><td> 47743-720 </td></tr><tr><td> EBM2 kit </td><td> Lonza </td><td> CC-3156 </td></tr><tr><td> Nikon ECLIPSE TS100 Mikroskop </td><td> Nikon </td><td></td></tr></tbody></table>

a matrigel-based tube formation assay to assess the vasculogenic activity of tumor cells

Im Laufe der letzten Jahrzehnte, mit einem Rohr-Assay growth factor-reduzierten Matrigel wurde in der Regel eingesetzt, um die angiogene Aktivität des vaskulären endothelialen Zellen in vitro 1-5 demonstrieren. Allerdings hat vor kurzem immer mehr Belege dafür ergeben, dass dieser Test nicht beschränkt auf vaskuläre Verhalten für Endothelzellen zu testen. Stattdessen hat sie auch benutzt worden, um die Fähigkeit einer Reihe von Tumorzellen zu einer vaskulären Phänotyp 6-8 Entwicklung zu testen. Diese Fähigkeit wurde in Übereinstimmung mit ihren vaskulogene Verhalten in xenotransplantierten Tiere, ein Verfahren, wie vaskulogene Mimikry (VM) 9 bekannt sind, identifiziert. Es gibt eine Vielzahl von Nachweisen dafür, dass Tumor-Zell-vermittelten VM spielt eine wichtige Rolle bei der Tumorentwicklung, unabhängig von Endothelzellen Angiogenese 6, 10-13. So wurden zum Beispiel Tumorzellen im Blut durchströmt, vaskuläre Kanalbildung in Gewebeproben aus Melanomen und Glioblastom-Patienten 8, 10, 11 zu beteiligen. Hier haben wir beschrieben, diese röhrenförmigen Netz-Assay als ein nützliches Instrument bei der Auswertung von vaskulären Aktivität von Tumorzellen. Wir fanden, dass einige Tumorzelllinien wie Melanom B16F1 Zellen, Glioblastom U87-Zellen, und Brustkrebs MDA-MB-435 Zellen in der Lage, vaskuläre Tubuli bilden; einige aber auch nicht wie Darmkrebs HCT116-Zellen. Darüber hinaus ist dieses vaskulären Phänotyp abhängig Zellzahlen auf dem Matrigel beschichtet. Daher kann dieser Test als leistungsstarkes Dienstprogramm für die vaskuläre Potenzial einer Vielzahl von Zelltypen einschließlich vaskulärer Zellen, Tumorzellen sowie anderen Zellen Bildschirm dienen.

Watch this Scientific Journal Video about A Matrigel-Based Tube Formation Assay to Assess the Vasculogenic Activity of Tumor Cells at JoVE.com

A Matrigel-Based Tube Formation Assay to Assess the Vasculogenic Activity of Tumor Cells

Ein Rohr-Assay wird verwendet, um vaskuläre Aktivität von Tumorzellen zu bewerten.

Ein Matrigel-Based Rohr Formation Assay zur vaskulären Aktivität von Tumorzellen Beurteilen

Over the past several decades, a tube formation assay using growth factor-reduced Matrigel has been typically employed to demonstrate the angiogenic ...

a-matrigel-based-tube-formation-assay-to-assess-vasculogenic-activity

Research

JoVE Journal

Biology

66.0K Aufrufe.  University of Massachusetts. Ein Rohr-Assay wird verwendet, um vaskuläre Aktivität von Tumorzellen zu bewerten.

Serie: A Matrigel-Based Tube Formation Assay to Assess the Vasculogenic Activity of Tumor Cells

Optimized Fibrin Gel Bead Assay for the Study of Angiogenesis

Angiogenesis is a complex multi-step process, where, in response to angiogenic stimuli, new vessels are created from the existing vasculature.  These steps include: degradation of the basement membrane, proliferation and migration (sprouting) of endothelial cells (EC) into the extracellular matrix, alignment of EC into cords, branching, lumen formation, anastomosis, and formation of a new basement membrane.  Many in vitro assays have been developed to study this process, but most only mimic certain stages of angiogenesis, and morphologically the vessels within the assays often do not resemble vessels in vivo.  Based on earlier work by Nehls and Drenckhahn, we have optimized an in vitro angiogenesis assay that utilizes human umbilical vein EC and fibroblasts.  This model recapitulates all of the key early stages of angiogenesis and, importantly, the vessels display patent intercellular lumens surrounded by polarized EC. EC are coated onto cytodex microcarriers and embedded into a fibrin gel.  Fibroblasts are layered on top of the gel where they provide necessary soluble factors that promote EC sprouting from the surface of the beads.  After several days, numerous vessels are present that can easily be observed under phase-contrast and time-lapse microscopy. This video demonstrates the key steps in setting up these cultures.

This video demonstrates the protocol of an in vitro angiogenesis assay that recapitulates several stages of angiogenesis. Time-lapse images of sprouting, lumen formation, branching and anastomosis - key features of angiogenesis - are shown.

Optimierte Fibringel Bead Assay für das Studium der Angiogenese

Angiogenesis is a complex multi-step process, where, in response to angiogenic stimuli, new vessels are created from the existing vasculature.  These ...

Forschung

Biologie

A Comprehensive Procedure to Evaluate the In Vitro Performance of the Putative Hemangioblastoma Neovascularization Using the Spheroid Sprouting Assay

The inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene plays a crucial role in the development of hemangioblastomas (HBs) within the human central nervous system (CNS). However, both the cytological origin and the evolutionary process of HBs (including neovascularization) remain controversial, and anti-angiogenesis for VHL-HBs, based on classic HB angiogenesis, have produced disappointing results in clinical trials. One major obstacle to the successful clinical translation of anti-vascular treatment is the lack of a thorough understanding of neovascularization in this vascular tumor. In this article, we present a comprehensive procedure to evaluate in vitro whether classic tumor angiogenesis exists in HBs, as well as its role in HBs. With this procedure, researchers can accurately understand the complexity of HB neovascularization and identify the function of this common form of angiogenesis in HBs. These protocols can be used to evaluate the most promising anti-vascular therapy for tumors, which has high translational potential either for tumors treatment or for aiding in the optimization of the anti-angiogenic treatment for HBs in future translations. The results highlight the complexity of HB neovascularization and suggest that this common form angiogenesis is only a complementary mechanism in HB neovascularization.

A Comprehensive Procedure to Evaluate the In Vitro Performance of the Putative Hemangioblastoma Neovascularization Using the Spheroid Sprouting Assay

This paper presents a comprehensive procedure to evaluate in vitro whether classic tumor angiogenesis exists in hemangioblastomas (HBs) and its role in HBs. The results highlight the complexity of HB-neovascularization and suggest that this common form of angiogenesis is only a complementary mechanism in the HB-neovascularization.

Ein umfassendes Verfahren zur Bewertung der In-vitro- Leistung von der vermeintlichen Hämangioblastom Neovaskularisation mit den Sphäroid sprießen Assay

The inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene plays a crucial role in the development of hemangioblastomas (HBs) within the human ...

Krebsforschung

Fibroblast-Derived 3D Matrix System Applicable to Endothelial Tube Formation Assay

The extracellular matrix (ECM) is a three-dimensional scaffold that acts as the main support for cells in tissues. Besides its structural function, the ECM also participates in cell migration, proliferation, and differentiation. Fibroblasts are the main type of cells modifying ECM fiber arrangement and production. In cancer, CAFs (cancer associated fibroblasts) are in permanent activation status, participating in ECM remodeling, facilitating tumor cell migration, and stimulating tumor-associated angiogenesis, among other pro-tumorigenic roles. The objective of this method is to create a three-dimensional matrix with a fiber composition that is similar to in vivo matrices, using immortalized fibroblasts or human primary CAFs. Fibroblasts are cultured in pre-treated cell culture plates and grown under ascorbic acid stimulation. Then, fibroblasts are removed and matrices are blocked for further cell seeding. In this ECM model, fibroblasts can be activated or modified to generate different kinds of matrix, whose effects can be studied in cell culture. 3D matrices are also shaped by cell signals, like degradation or cross-linking enzymes that might modify fiber distribution. In this context, angiogenesis can be studied, along with other cell types such as epithelial tumor cells.

The aim of this method is to obtain fibroblast-derived 3D matrices as a natural scaffold for subsequent cellular assays. Fibroblasts are seeded in a pre-treated culture plate and stimulated with ascorbic acid for matrix generation. Matrices are decellularized and blocked to culture relevant cells (e.g., endothelial cells).

Fibroblast-Derived 3D Matrix System anwendbar auf Endothel Tube Formation Assay

The extracellular matrix (ECM) is a three-dimensional scaffold that acts as the main support for cells in tissues. Besides its structural function, the ...

HUVEC Tube-formation Assay to Evaluate the Impact of Natural Products on Angiogenesis

Angiogenesis is a phenomenon that includes different processes, such as endothelial cell proliferation, differentiation, and migration, that lead to the formation of new blood vessels and involve several signal transduction pathways. Here we show that the tube formation assay is a simple in vitro method to evaluate the impact of natural products on angiogenesis and to investigate the molecular mechanisms involved. In particular, in the presence of the water extract of Ruta graveolens (RGWE), endothelial cells are no longer able to form a cell-cell network and that the RGWE effects on human umbilical vein endothelial cell (HUVEC) tube formation is abolished by the constitutive activation of MEK.

Here, we evaluate the effects of the water extract of Ruta graveolens on vessel network formation by using a tube formation assay on a gelled basement matrix.

HUVEC Tube-Formation Assay zur Bewertung der Auswirkungen natürlicher Produkte auf die Angiogenese

Angiogenesis is a phenomenon that includes different processes, such as endothelial cell proliferation, differentiation, and migration, that lead to the ...

Entwicklungsbiologie

An In Vitro 3D Model and Computational Pipeline to Quantify the Vasculogenic Potential of iPSC-Derived Endothelial Progenitors

Induced pluripotent stem cells (iPSCs) are a patient-specific, proliferative cell source that can differentiate into any somatic cell type. Bipotent endothelial progenitors (EPs), which can differentiate into the cell types necessary to assemble mature, functional vasculature, have been derived from both embryonic and induced pluripotent stem cells. However, these cells have not been rigorously evaluated in three-dimensional environments, and a quantitative measure of their vasculogenic potential remains elusive. Here, the generation and isolation of iPSC-EPs via fluorescent-activated cell sorting are first outlined, followed by a description of the encapsulation and culture of iPSC-EPs in collagen hydrogels. This extracellular matrix (ECM)-mimicking microenvironment encourages a robust vasculogenic response; vascular networks form after a week of culture. The creation of a computational pipeline that utilizes open-source software to quantify this vasculogenic response is delineated. This pipeline is specifically designed to preserve the 3D architecture of the capillary plexus to robustly identify the number of branches, branching points, and the total network length with minimal user input.

Endothelial progenitors derived from induced pluripotent stem cells (iPSC-EPs) have the potential to revolutionize cardiovascular disease treatments and to enable the creation of more faithful cardiovascular disease models. Herein, the encapsulation of iPSC-EPs in three-dimensional (3D) collagen microenvironments and a quantitative analysis of these cells&#8217; vasculogenic potential are described.

Ein In-Vitro-3D-Modell und eine Computational Pipeline zur Quantifizierung des vaskulogenen Potenzials von iPSC-derived endotheliaalen Vorläufern

Induced pluripotent stem cells (iPSCs) are a patient-specific, proliferative cell source that can differentiate into any somatic cell type. Bipotent ...

Strategic Endothelial Cell Tube Formation Assay: Comparing Extracellular Matrix and Growth Factor Reduced Extracellular Matrix

Malignant tumors require a blood supply in order to survive and spread. These tumors obtain their needed blood from the patient's blood stream by hijacking the process of angiogenesis, in which new blood vessels are formed from existing blood vessels. The CXCR2 (chemokine (C-X-C motif) receptor 2) receptor is a transmembrane G-protein-linked molecule found in many cells that is closely associated with angiogenesis1. Specific blockade of the CXCR2 receptor inhibits angiogenesis, as measured by several assays such as the endothelial tube formation assay. The tube formation assay is useful for studying angiogenesis because it is an excellent method of studying the effects that any given compound or environmental condition may have on angiogenesis. It is a simple and quick in vitro assay that generates quantifiable data and requires relatively few components. Unlike in vivo assays, it does not require animals and can be carried out in less than two days. This protocol describes a variation of the extracellular matrix supporting endothelial tube formation assay, which tests the CXCR2 receptor.

This manuscript describes a tube formation assay to quantify the effects of a given compound or condition on angiogenesis by using endothelial cell tube formation in a controlled environment.

Strategische Endothelzell Tubusbildung Assay: Ein Vergleich extrazellulären Matrix und Wachstumsfaktor Reduzierte Extrazellulärmatrix

Malignant tumors require a blood supply in order to survive and spread. These tumors obtain their needed blood from the patient's blood stream by ...

Medizin

Analyzing Angiogenesis: In Vitro Assay for Tube Formation on BM Matrix

Trophoblast Cell Recovery from Angiogenesis-Tube Formation Assay for Differentiation Marker Expression Analysis

During placenta development, extravillous trophoblast (EVT) cells invade the maternal decidua to remodel the uterine spiral arteries by a process of mesenchymal to endothelial-like transition. Traditionally, this process is evaluated by an in vitro tube-formation assay, where the cells organize themselves into tube-like structures when seeded over a polymerized basement membrane preparation. Although several structural features can be measured in photomicrographs of the structures, to assess the real commitment of EVT to the endothelial-type phenotype, biochemical analysis of cell extracts is required. Scraping the cells from the culture dish to obtain RNA and/or protein extracts is not an alternative since the tube-like structures are severely contaminated by the bulk of proteins from the polymerized basement membrane. Thus, a strategy to separate the cells from the basement membrane proteins prior to the preparation of cell extracts is needed. Here, a simple, fast, and cost-effective method to recover the tube-like structures from the in vitro tube-formation assay and the subsequent analysis by biochemical techniques is presented. Tube-like structures formed by HTR8/SVneo cells, an EVT cell line, were liberated from the polymerized basement membrane by a short incubation with PBS supplemented with ethylenediaminetetraacetic acid (EDTA). After serial washes, a ready-to-use pellet of purified tube-like structures can be obtained. This pellet can be subsequently processed to obtain RNA and protein extracts. qPCR analysis evidenced the induced expression of VE-cadherin and alphav-integrin, two endothelial cell markers, in EVT-derived tube-like structures compared to control cells, which was consistent with the induction of the endothelial cell marker, CD31, evaluated by immunofluorescence. Western blot analysis of the tube-like structures' protein extracts revealed the overexpression of RECK in transfected HTR8/SVneo cells. Thus, this simple method allows to obtain cell extracts from the in vitro tube-formation assay for the subsequent analysis of RNAs and protein expression.

The present protocol allows the recovery of tube-like structures formed in the classical in vitro angiogenesis-tube formation assay where cells, such as trophoblast cells, organize in capillary-like structures over a layer of extracellular basement membrane matrix. The recovered structures are used for RNA and protein isolation for various biochemical analyses.

During placenta development, extravillous trophoblast (EVT) cells invade the maternal decidua to remodel the uterine spiral arteries by a process of ...

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 this protocol, angiogenesis may be measured in vitro in a fast, quantifiable manner. Primary or immortalized endothelial cells are mixed with conditioned media and plated on basement membrane matrix. The endothelial cells form capillary like structures in response to angiogenic signals found in conditioned media. The tube formation occurs quickly with endothelial cells beginning to align themselves within 1&#160;hr and lumen-containing tubules beginning to appear within 2 hr. Tubes can be visualized using a phase contrast inverted microscope, or the cells can be treated with calcein AM prior to the assay and tubes visualized through fluorescence or confocal microscopy. The number of branch sites/nodes, loops/meshes, or number or length of tubes formed can be easily quantified as a measure of in vitro angiogenesis. In summary, this assay can be used to identify genes and pathways that are involved in the promotion or inhibition of angiogenesis in a rapid, reproducible, and quantitative manner.

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

The tube formation assay is a fast, quantifiable method for measuring in vitro angiogenesis. Endothelial cells are combined with conditioned media and plated on basement membrane extract. Tube formation occurs within hours and newly formed tubules easily quantified.

Endothelzellen Schlauchbildung Assay für die<em&gt; In-vitro-</em&gt; Studium der Angiogenese

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

Monitoring Functionality and Morphology of Vasculature Recruited by Factors Secreted by Fast-growing Tumor-generating Cells

The subcutaneous matrigel plug assay in mice is a method of choice for the in vivo evaluation of pro- and anti-angiogenic factors. In this method, desired factors are introduced into cold-liquid ECM-mimic gel which, after subcutaneous injection, solidifies to form an environment mimicking the cancer milieu. This matrix permits the penetration of host cells, such as endothelial cells, and therefore, the formation of vasculature.
Herein we propose a new modified matrigel plug assay, which can be exploited to illustrate the angiogenic potential of a pool of factors secreted by cancer cells, as opposed to a specific factor (e.g., bFGF and VEGF) or agent. The plug containing ECM-mimic gel is utilized to introduce the host (i.e., mouse) with a pool of factors secreted to the C.M. of fast-growing tumor-generating glioblastoma cells. We have previously described an extensive comparison of the angiogenic potential of U-87 MG human glioblastoma and its dormant-derived clone, in this system model, showing induced angiogenesis in the U-87 MG parental cells. The C.M. is prepared by filtering collected media from confluent tissue culture plates of either cell line following 48 hr incubation. Hence, it contains only factors secreted by the cells, without the cells themselves. Described here is the combination of two imaging modalities, microbubbles contrast-enhanced ultrasound imaging and intravital fibered-confocal endomicroscopy, for an accurate, real-time characterization of the extent, morphology and functionality of newly-formed blood vessels within the plugs.

We describe a matrigel plug assay to illustrate angiogenic potential of a pool of factors secreted by cancer cells using two complementary imaging modalities, ultrasound and endomicroscopy. The matrigel, an extracellular matrix (ECM)-mimic gel, is utilized to introduce the host (mouse) with angiogenic factors secreted to the conditioned media (C.M.).&#160;

Überwachungsfunktionen und Morphologie der Gefäßversorgung von Faktoren durch schnell wachsende Tumor erzeugende Zellen sezerniert rekrutiert

The subcutaneous matrigel plug assay in mice is a method of choice for the in vivo evaluation of pro- and anti-angiogenic factors. In this method, desired ...

Untersuchung der Angiogenese mit Hilfe von Scratch-Wund-Migration und Sphäroid-Skeim-Assays

Investigating Angiogenesis on a Functional and Molecular Level by Leveraging the Scratch Wound Migration Assay and the Spheroid Sprouting Assay

Angiogenesis plays a crucial role in both physiological and pathological processes within the body including tumor growth or neovascular eye disease. A detailed understanding of the underlying molecular mechanisms and reliable screening models are essential for targeting diseases effectively and developing new therapeutic options. Several in vitro assays have been developed to model angiogenesis, capitalizing on the opportunities a controlled environment provides to elucidate angiogenic drivers at a molecular level and screen for therapeutic targets.
This study presents workflows for investigating angiogenesis in vitro using human umbilical vein endothelial cells (HUVECs). We detail a scratch wound migration assay utilizing a live cell imaging system measuring endothelial cell migration in a 2D setting and the spheroid sprouting assay assessing endothelial cell sprouting in a 3D setting provided by a collagen matrix. Additionally, we outline strategies for sample preparation to enable further molecular analyses such as transcriptomics, particularly in the 3D setting, including RNA extraction as well as immunocytochemistry. Altogether, this framework offers scientists a reliable and versatile toolset to pursue their scientific inquiries in in vitro angiogenesis assays.

Autor im Rampenlicht: Untersuchung der Angiogenese durch Herausforderungen und Innovationen in der Assay-Entwicklung

This study presents the two-dimensional (2D) scratch wound migration assay and the three-dimensional (3D) spheroid sprouting assay, along with their respective downstream analysis methods, including RNA extraction and immunocytochemistry, as suitable assays to study angiogenesis in vitro.

Untersuchung der Angiogenese auf funktioneller und molekularer Ebene durch Nutzung des Scratch Wound Migration Assay und des Spheroid Sprouting Assay

Angiogenesis plays a crucial role in both physiological and pathological processes within the body including tumor growth or neovascular eye disease. A ...