Diese Arbeit wurde nacheinander von einem NFS Frontiers in Genetics Pilot Auszeichnung, Juvenile Diabetes Research Foundation Grants 41-2009-775 und Grant 12-126875 von Det Frie forskningsråd / Sundhed og Sygdom finanziert. Die Autoren danken der Spagnoli Labor für die Ausrichtung der Videoaufnahmen.

Dieses Protokoll zielt darauf ab, zu wachsen Bauchspeicheldrüsen Organoide aus murinen E10.5 abgeleitet dissoziiert epithelialen Zellen der Bauchspeicheldrüse. Das Protokoll erfordert ethische Genehmigung für Tierversuche. 1. Präparation der dorsalen Pankreas-Knospe von E10.5 Maus Embryonen <ol><li> Sacrifice timed-schwangeren Mäusen an embryonalen Tag (E) 10.5, öffnen Sie den Bauch mit einer Schere entfernen Sie die beiden Uterushörner und legen Sie sie in einem 10-cm-Petrischale mit kaltem Phosphat-Pufferlösung (PBS) gefüllt oder Dulbecco modifiziertem essentiellen Medium (DMEM) auf Eis gehalten. Die Gesamt Experiment aus dem Opfer zu Zellaussaat ist in 60-90 Minuten durchgeführt, um Zellschäden zu verhindern. </li><li> Trennen Sie die Gebärmutter in einzelne Segmente Embryo mit einer kleinen Schere. Übertragen eines Embryos auf eine 35 mm Petrischale mit kaltem PBS und visualisieren sie unter einem Binokular mit Beleuchtung von oben. Mit einer Pinzette entfernen Dissektion der umliegenden Muskeln, decidua und Dotter sac und setzen den Embryo. Setzen Sie den Embryo wieder in kaltem DMEM Medium. Embryonen kann leicht mit Hilfe eines 3-ml-Plastiktransferpipette / Dropper übertragen werden. Isolieren jedes einzelnen Embryos in ähnlicher Weise vor dem Fortfahren. </li><li> Legen Sie einen Embryo in eine saubere 35-mm-Petrischale in PBS. <ol><li> Verwenden dünnen Pinzette (0,05 mm Breite), um die Vordergliedmaße zu entfernen. Sanft die Zange im Öffnungseinsatz um den Verdauungstrakt aus dem Rückenmark Region (Fig. 1) zu lösen. Optional: Um bequemer sehen den Magen, entfernen Sie den Oberkörper des Embryos, bis hin zu Herz-und Heckbereich unterhalb des Dotter Stiel. </li><li> Suchen Sie den Magen, Leber und Darm. Mit den Zangen, isolieren die Magen-Darmtrakt aus dem Magen in den Darm und legen Sie sie in kaltem DMEM auf Eis (Abbildung 1). Die dorsale Pankreas Knospe dorsal angebracht, hinter dem Magen (Abbildung 1). </li><li> Isolieren Sie jeden einzelnen Magen-Darm-Trakt in einer ähnlar Weise, bevor Sie fortfahren. Wenn die Embryonen müssen genotypisierende, sammeln den Schwanz zum Zeitpunkt der Präparation und halten jeden einzelnen Magen-Darm-Trakt in einem anderen auch in einer 24-Well-Platte mit kaltem DMEM auf Eis. </li></ol></li><li> Legen Sie ein Magen-Darm-Trakt in einem sauberen 35 mm Petrischale in kaltem PBS. Jetzt benutze Beleuchtung von unten in Hellfeld unter der Dissektionsmikroskop visualisieren und sezieren die dorsalen Pankreas Knospe. Diese Bedingungen werden die Visualisierung von Volumen zu optimieren. Mit elektrolytisch geschärften Wolfram Nadeln oder 20 G Spritzennadeln, isolieren das Pankreas Knospe mit so wenig wie möglich um Mesenchym des Epithels (Abbildung 1). <ol><li> Übertragen der isolierten Knospe in eine Petrischale mit einem kalten Dispase-Lösung (1,25 mg / ml) für 2-3 min. Von diesem Punkt kann die Übertragung am einfachsten mit flamm gezogen 50 ul Glaskapillaren mit einem Mund-gesteuerten flexiblen Schlauch befestigt erfolgen. Alternativ, aber mit mehr risk verlieren die Knospe, verwenden Sie eine 10 ul automatischen Pipette (Pipetman) mit entsprechenden Kunststoffspitzen. </li><li> Führen Pankreas Knospe Aspiration und Ausstoß unter mikroskopischer Kontrolle. Setzen Sie den Pankreas Knospe zurück in PBS. Weitere aus dem Mesenchym mit den Nadeln und leichtes Ansaugen mit der Glaskapillare (Abbildung 1) reinigen die isolierte Pankreasknospe. </li><li> Wenn das gesamte Mesenchym entfernt ist, spülen Sie die Pankreas Knospe in kaltem PBS; Übertragen Sie jede Knospe zu kalt DMEM in einzelnen Vertiefungen (60-well Mini-Trays mit 10 ul kalten DMEM gefüllt). Es ist wichtig, das Mesenchym in Dispase zu entfernen, die das Gewebe sehr klebrig macht. </li></ol></li></ol> 2. Überzug und Kultur der dispergierten Zellen <ol><li> Übertragen Sie die seziert Epithelien aus allen Embryonen mit einem flamm gezogen Glaskapillare in konische Vertiefungen der 60-Well-Mini-Trays mit 10 ul PBS gefüllt zum Spülen. <ol><li> Übertragen Sie die Knospe in 10 ul Trypsin 0,05% einnd lassen Sie es bei 37 ° C inkubieren 4 min. Inaktivierung des Trypsins durch Übertragen der Keim in einem gut mit 10 &amp;mgr; l DMEM + 10% fötales Kälberserum (FCS). </li><li> Distanzieren Sie die Zellsuspension durch Aspiration durch eine dünne Kapillare mit einer Pipette Puller gezogen. Es ist wichtig, um Blasen zu vermeiden, in dieser Phase, während und Abpipettieren, um die Zellen zu distanzieren. Bauchspeicheldrüse Organoide optimal vor kleinen Gruppen von 5-15 Zellen beginnen und deshalb teilweise Dissoziation empfohlen (Abbildung 1). </li></ol></li><li> Pool der Zellen aus mehreren Embryonen in ein Eppendorf-Röhrchen, um die Unterschiede aufgrund der individuellen Verarbeitung zu minimieren. Verdünnen Sie die Zellsuspension in gekühlten Matrigel bei einem Verhältnis von 1:3. Aliquote dieser Mischung in eine 96-Well-Platte, 8 &amp;mgr; l / Vertiefung in einer Platte oder für die Abbildung optimiert (siehe unten). </li><li> Inkubieren der Platte bei 37 ° C für 5 Minuten, so dass die Matrigel zu verdicken. Füllen Sie die Vertiefungen mit 70 ul Medium der Wahl (Organoid oder Kugel, siehe Tab.les 1 und 2) und lassen in einer befeuchteten Umgebung mit 5% CO 2 und 95% Luft bei 37 ° C. </li><li> Jeden 4. Tag Ersetzen Sie das Medium. Überwachen Sie die wachsenden Kolonien Bauchspeicheldrüsen täglich und dokumentieren den Prozess durch Bildgebung. </li><li> Kleine Moleküle oder Proteine ​​von Interesse können dem Medium zu diesem Zeitpunkt für Interferenzexperimente hinzugefügt werden, wie vorher 28 gemeldet. </li></ol> Tabelle 1: Organoide Medium. <table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td> Name des Materials </td><td> Auf Konzentration </td><td> Konzentration in endgültige Medium </td><td> Volumen der Stamm </td></tr><tr><td> Penicillin-Streptomycin </td><td> 100% </td><td> 1% </td><td> 50 ul </td></tr><tr><td> KnockOut Serum Ersatz (Ergänzung) </td><td> 100% </td><td> 10% </td><td> 500 ul </td></tr><tr><td> 2-Mercaptoethanol </td><td> 14,3 M </td&gt; <td> 0,1 mM </td><td> 1 ul </td></tr><tr><td> Phorbol-Myristat-Acetat (PMA) </td><td> 16 uM </td><td> 16 nM </td><td> 5 ul </td></tr><tr><td> Y-27632 (ROCK-Inhibitor) </td><td> 50 mM </td><td> 10 uM </td><td> 1 ul </td></tr><tr><td> EGF </td><td> 50 &amp;mgr; g / ml </td><td> 25 ng / ml </td><td> 2,5 ul </td></tr><tr><td> Rekombinantem humanem R-1 Spondin </td><td> 250 &amp;mgr; g / ml </td><td> 500 ng / ml </td><td> 10 ul </td></tr><tr><td> - Oder - </td><td></td><td></td><td></td></tr><tr><td> Recombinant Mouse R-1 Spondin </td><td> 250 &amp;mgr; g / ml </td><td> 500 ng / ml </td><td> 10 ul </td></tr><tr><td> Rekombinantem humanem FGF1 (aFGF) </td><td> 100 &amp;mgr; g / ml </td><td> 25 &amp;mgr; g / ml </td><td> 1,25 ul </td></tr><tr><td> Heparin (Liquemin) </td><td> 2500 U / ml </td><td> 2,5 U / ml </td><td> 2 ul </td></tr><tr><td> Recomnante Menschen FGF10 </td><td> 100 &amp;mgr; g / ml </td><td> 100 ng / ml </td><td> 5 ul </td></tr><tr><td> DMEM/F-12 </td><td></td><td></td><td> 4,412.25 ul </td></tr><tr><td> Gesamt </td><td></td><td></td><td> 5000 ul </td></tr></tbody></table> Tabelle 2: Sphere Medium. <table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td> Name des Materials </td><td> Auf Konzentration </td><td> Konzentration in endgültige Medium </td><td> Volumen der Stamm </td></tr><tr><td> Penicillin-Streptomycin </td><td> 100% </td><td> 1% </td><td> 50 ul </td></tr><tr><td> B27 x50 (Ergänzung) </td><td> 100% </td><td> 10% </td><td> 100 ul </td></tr><tr><td> Recombinant Human FGF2 (bFGF) </td><td> 100 &amp;mgr; g / ml </td><td> 64 ng / ml </td><td> 3.2 ul </td></tr><tr><td> Y-27632 (ROCK-Inhibitor) </td><td> 50 mM </td><td> 10 uM </td><td> 1 ul </td></tr><tr><td> DMEM/F-12 </td><td></td><td></td><td> 4845,8 ul </td></tr><tr><td> Gesamt </td><td></td><td></td><td> 5000 ul </td></tr></tbody></table> 3. Imaging der Progression der Organoide Entwicklung <ol><li> Bild Organoide mit einem fluoreszierenden Zeitraffer-Mikroskop entweder täglich oder Zeitraffer-Mikroskopie. Für Zeitreihen-Aufnahmen, verwenden Sie ein XY (Z) automatisierte invertierten Fluoreszenzmikroskop. </li><li> Kaution kleine Tröpfchen von 3 ul in 4-Well-Platten oder Glasbodenplatten mit 2-5 ml Medium gefüllt ist. Bild mit einem 10-fach Fernziel. Hinweis: Transgene Mäuse, die fluoreszierenden Indikatoren verwendet werden. Film 1 zeigt zum Beispiel die anfängliche Expansion Organoide von Pdx1-Ngn3-ER TM-IRES-nGFP + 4 Mäuse. Die Kern GFP ermöglicht dem Benutzer, Zellen zu verfolgen als einzelne Objekte aber ähnliche Prinzipien angewendet werden, um Zellen mit Membran Fluoreszenz verfolgt werden,als mT / mg Mäuse 29. </li><li> Starten Zeitraffer-Bildgebung 3 Stunden nach dem Aussäen der Zellen, um den Fokus Verwehungen zu vermeiden und setzen die Software die Steuerung Automatisierung, um ein Bild / h für 3 oder mehr Tage bei manuell definierten Positionen zu nehmen. Für jede Position, erwerben eine Differentialinterferenzkontrast (DIC), als auch die GFP-Signal, Reporting Fluoreszenzmarker Ausdruck. </li></ol> 4. Wiederherstellung von Organoide für Histologie <ol><li> Legen Sie die 96-Well-Platte auf Eis und entfernen Sie das Medium, mit eiskaltem PBS ersetzt. Diese teilweise depolymerisiert Matrigel. </li><li> Vorsichtig absaugen jedes einzelne OBs, das Entfernen der umgebenden Matrigel mit einem 1000 ul Spitze, um die Gesamtarchitektur nicht zu stören. Übertragen Sie jede Organoid zu einem gut mit eiskaltem PBS. Halten Sie die Platte auf Eis. Direktbefestigung in Matrigel ist ebenfalls möglich. </li><li> Befestigen Sie die Organoid für 15 min in 4% Paraformaldehyd (PFA), Kryokonservierung in Saccharose und binde sie in Gelatine. An jederorganoiden für Kryoschneiden und Histologie wie zuvor beschrieben (Johansson et al., 2007) 4. </li></ol> 5. Organoide Erholung der für die PCR und Biochemie <ol><li> Legen Sie die 96-Well-Platte auf Eis und entfernen Sie das Medium. In 60 ul pro RNAlater auch zur Stabilisierung und zum Schutz zellulärer RNA. </li><li> Stört Sie das Gel in jedem gut mechanisch durch teilweise Depolymerisation es auf Eis. Entweder erholen einzelnen Organoide mit einem 1000 ul Spitze, um die Gesamtarchitektur nicht stören oder Wiederherstellung der kompletten gut (mit Matrigel) durch Unterbrechung der Gel mechanisch mit einer 200 ul Spitze. Verwenden Sie ein 1.000 ul Spitze, die auch Inhalt in ein RNase-frei nicht klebrig Eppendorf-Röhrchen übertragen auf Eis gehalten. </li><li> Waschen Sie die Vertiefungen mit 60 ul RNAlater und das restliche Inhalt zum gleichen Eppendorf-Röhrchen. </li><li> Dreh die Röhrchen für 5 min bei 500-1.000 x g bei 4 ° C. </li><li> Entfernen Sie den Überstand, so dass nur 20-30 ulRNAlater in das Rohr zusammen mit dem Pellet. Für Biochemie, speichern Sie die Proben so trocken wie möglich. </li><li> Proben in RNAlater sofort nicht einfrieren; bei 4 ° CO / N (damit RNAlater, um das Gewebe gründlich zu durchdringen). Das Gewebe kann bei -20 ° C zur Langzeitspeicher gespeichert werden und können später zur Gewebezerstörung und Extraktion von kleinen Mengen von RNA verarbeitet werden. </li></ol>

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D., Tasic, B., Miyamichi, K., Li, L., Luo, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+global+double-fluorescent+Cre+reporter+mouse.">A global double-fluorescent Cre reporter mouse.</a> Genesis. 45, 593-605 (2007).</li></ol>

The authors have nothing to disclose.

Großtechnische Produktion von Funktions Beta-Zellen in vitro ist immer noch ineffektiv ein. In diesem schwierigen Kontext kann der Entwicklungsbiologie Studien helfen, die Entschlüsselung der Signale, die exakte für die Differenzierung von funktionellen Beta-Zellen benötigt werden. Dieses Protokoll ermöglicht die Erhaltung, Expansion und Differenzierung der Pankreas-Vorläuferzellen in embryonalen vitro. Dazu gehören die Bildung von Insulin-produzierenden Beta-Zellen, die nich...

Orgelkultur bietet ein nützliches Modell, das die Lücken zwischen der komplexen, aber sehr relevant in-vivo-Untersuchungen und die bequeme, aber ungefähre Simulation von Zelllinie Modelle überbrückt. Im Falle der Bauchspeicheldrüse, gibt es keine Zelllinie perfekt entspricht Pankreas-Vorläufer, obwohl es sind transformierte Zellinien Simulation endokrine und exokrine Zellen. Die erwachsenen ganze Bauchspeicheldrüse kann nicht kultiviert werden; endokrinologischen Inseln können für einige Wochen beibehalten werden, ohne die Zellproliferation und Gewebeschnitten können in vitro für einige Stunden 5 gehalten werden. Embryonale Bauchspeicheldrüse Kultur ist weit verbreitet, nicht nur ihre Entwicklung zu studieren, sondern auch epitheliale-mesenchymale Interaktionen 4,6,7 untersuchen, Bild verarbeitet 8 oder 9, um mit ihnen chemisch stören. Zwei Orgelkultur Methoden werden hauptsächlich verwendet: Die erste besteht in der Kultivierung von Bauchspeicheldrüsenknospen auf Fibronektin-beschichtete Platten 2, das ist komfortabler zur Bildgebung; Die zweite Möglichkeit ist die Kultur die Organe über Filter an der Luft-Flüssigkeit-Grenzfläche, die 3,4 am besten bewahrt Morphogenese. Obwohl sehr nützlich führen diese Verfahren zu einem gewissen Grad der Abflachung; der Ausbau der Vorläufer sehr begrenzt im Vergleich zu der normalen Entwicklung und der Ausgangspopulation Komplex, alle Typen von pankreatischen Zellen und mesenchymalen Zellen. Die Fähigkeit, Kultur und erweitern verteilten Primärzellen ist wertvoll für Linie Beziehungen zu studieren und entdecken Sie die intrinsischen Eigenschaften von isolierten Zelltypen 10. Sugiyama et al 11. Könnte Pankreas-Vorläufern und endokrine Vorläuferzellen, die einige funktionale Zeichen für 3-5 Tage in Kultur auf Feeder-Schichten beibehalten zu halten. Pancreatospheres, ähnlich Neurosphären mammospheres 12 und 13 sind aus adulten Inseln und duktalen Zellen erweitert worden, obwohl die Art der Vorläufer / Stammzellen, die diese Kugeln zu erzeugen, ist nicht klar. Darüber hinaus im Gegensatz physiologische Entwicklung enthielten die pancreatospheres einige Neuronen 14,15. Kugeln wurden vor kurzem auch aus embryonalen Vorläuferzellen der Bauchspeicheldrüse 16,17 und regenerierende Bauchspeicheldrüsen 18 mit guten Vorläufer Expansion und nachfolgende Differenzierung produziert aber nicht Morphogenese rekapitulieren. 3D-Modelle aus dispergierten, oft definierte Zellen, die durch Selbstorganisation miniaturisierten Organen mit blühten und simulieren die Entwicklung oder Erwachsener Umsatz von mehreren Organen, wie dem Darm 19,20, dem Magen 21, Leber 22, die Prostata 23 und die Trachea 24. In einigen Fällen wurden Entwicklungs Morphogenese und Differenzierung von ES-Zellen 3D rekapituliert wurde, wie im Fall der Augenbecher 25, 26 Darm, Gehirn 27. Hier haben wir describe eine Methode, um multi dissoziierten Pankreas-Vorläuferzellen in einer 3D-Matrigel Gerüst, wo sie differenzieren können und selbst zu organisieren, zu erweitern.

<table border="0" cellpadding="0" cellspacing="0">
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		<tr>
			<td>Penicillin-Streptomycin</td>
			<td>Gibco</td>
			<td>15070-063</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>KnockOut Serum replacement (supplement)</td>
			<td>Gibco</td>
			<td>10828-028</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>2-mercaptoethanol</td>
			<td>Sigma Aldrich</td>
			<td>3148-25ML</td>
			<td>Stock keept at 4&#176;C</td>
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		<tr>
			<td>Phorbol Myristate Acetate (PMA)</td>
			<td>Calbiotech</td>
			<td>524400-1MG</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>Y-27632 (ROCK inhibitor)</td>
			<td>Sigma Aldrich</td>
			<td>ab120129</td>
			<td>Stock keept at -20&#176;C- Attention! Stability/source is a frequent source of problems</td>
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		<tr>
			<td>EGF</td>
			<td>Sigma Aldrich</td>
			<td>E9644-2MG</td>
			<td>Stock keept at -80&#176;C</td>
		</tr>
		<tr>
			<td>Recombinant Human R-spondin 1</td>
			<td>R&#38;D</td>
			<td>4645-RS-025/CF</td>
			<td>Stock keept at -80&#176;C</td>
		</tr>
		<tr>
			<td>&#160;- or -&#160;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant Mouse R-spondin 1</td>
			<td>R&#38;D</td>
			<td>3474-RS-050</td>
			<td>Stock keept at -80&#176;C</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant Human FGF1 (aFGF)</td>
			<td>R&#38;D</td>
			<td>232-FA-025</td>
			<td>Stock keept at -80&#176;C- do not include to increase beta cell production</td>
		</tr>
		<tr>
			<td>Heparin (Liquemin)</td>
			<td>Drossapharm</td>
			<td></td>
			<td>Stock keept at 4&#176;C</td>
		</tr>
		<tr>
			<td>Recombinant Human FGF10</td>
			<td>R&#38;D</td>
			<td>345-FG-025</td>
			<td>Stock keept at -80&#176;C</td>
		</tr>
		<tr>
			<td>DMEM/F-12</td>
			<td>Gibco</td>
			<td>21331-020</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin</td>
			<td>Gibco</td>
			<td>15070-063</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>B27 x50 (supplement)</td>
			<td>Gibco</td>
			<td>17504-044</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>Recombinant Human FGF2 (bFGF)</td>
			<td>R&#38;D</td>
			<td>233-FB-025</td>
			<td>Stock keept at -80&#176;C</td>
		</tr>
		<tr>
			<td>Y-27632 (ROCK inhibitor)</td>
			<td>Sigma Aldrich</td>
			<td>ab120129</td>
			<td>Stock keept at -20&#176;C- Attention! Stability/source is a frequent source of problems</td>
		</tr>
		<tr>
			<td>DMEM/F-12</td>
			<td>Gibco</td>
			<td>21331-020</td>
			<td></td>
		</tr>
		<tr>
			<td>Matrigel</td>
			<td>Corning</td>
			<td>356231</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>Trypsin 0.05%</td>
			<td>Gibco</td>
			<td>25300-054</td>
			<td>Stock keept at 4&#176;C</td>
		</tr>
		<tr>
			<td>RNAlater - RNA stabilizing reagent</td>
			<td>Qiagen</td>
			<td>76104</td>
			<td>Store at room temperature</td>
		</tr>
		<tr>
			<td>Dispase&#160;</td>
			<td>Sigma Aldrich</td>
			<td>D4818-2MG</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>BSA for reconstitution</td>
			<td>Milipore</td>
			<td><a href="http://www.millipore.com/catalogue/item/81-068-3">81-068</a></td>
			<td>For reconstituition of cytokines&#160; - Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>Fetal calf serum (FCS)</td>
			<td>Gibco</td>
			<td>16141079</td>
			<td>Stock keept at -20&#176;C</td>
		</tr>
		<tr>
			<td>60 well MicroWell trays</td>
			<td>Sigma Aldrich</td>
			<td>M0815-100EA</td>
			<td></td>
		</tr>
		<tr>
			<td>4-well plates</td>
			<td>Thermo Scientific</td>
			<td>176740</td>
			<td></td>
		</tr>
		<tr>
			<td>95-well plates F bottom</td>
			<td>Greiner Bio</td>
			<td>6555180</td>
			<td></td>
		</tr>
		<tr>
			<td>Glas bottom plates</td>
			<td>Ibidi</td>
			<td>81158</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposal micropittes</td>
			<td>Blaubrand</td>
			<td>708745</td>
			<td></td>
		</tr>
	</tbody>
</table>

in vitro pancreas organogenesis from dispersed mouse embryonic progenitors

The pancreas is an essential organ that regulates glucose homeostasis and secretes digestive enzymes. Research on pancreas embryogenesis has led to the development of protocols to produce pancreatic cells from stem cells 1. The whole embryonic organ can be cultured at multiple stages of development 2-4. These culture methods have been useful to test drugs and to image developmental processes. However the expansion of the organ is very limited and morphogenesis is not faithfully recapitulated since the organ flattens. 
We propose three-dimensional (3D) culture conditions that enable the efficient expansion of dissociated mouse embryonic pancreatic progenitors. By manipulating the composition of the culture medium it is possible to generate either hollow spheres, mainly composed of pancreatic progenitors expanding in their initial state, or, complex organoids which progress to more mature expanding progenitors and differentiate into endocrine, acinar and ductal cells and which spontaneously self-organize to resemble the embryonic pancreas. 
We show here that the in vitro process recapitulates many aspects of natural pancreas development. This culture system is suitable to investigate how cells cooperate to form an organ by reducing its initial complexity to few progenitors. It is a model that reproduces the 3D architecture of the pancreas and that is therefore useful to study morphogenesis, including polarization of epithelial structures and branching. It is also appropriate to assess the response to mechanical cues of the niche such as stiffness and the effects on cell&#180;s tensegrity.

E10.5 dorsalen Pankreasvorläuferzellen dissoziiert und in 3D Matrigel ausgesät rekapitulieren Bauchspeicheldrüse Entwicklung. Vorläufer lassen sich am einfachsten mit fluoreszierenden Reporter verfolgt werden. In unserem Fall haben wir eine transgene Maus, die ein Kernprotein mit GFP Pdx1 Promotor (Pdx1-Ngn3-ER-nGFP TM) (Film 1) in Abwesenheit von Tamoxifen und so gesteuert ohne Aktivierung NEUROG3 4 (Fig. 2) drückt. Mit dem organ...

Watch this Scientific Journal Video about In Vitro Pancreas Organogenesis from Dispersed Mouse Embryonic Progenitors at JoVE.com

In Vitro Pancreas Organogenesis from Dispersed Mouse Embryonic Progenitors

Die in diesem Protokoll beschriebenen dreidimensionalen Kulturverfahren rekapituliert Bauchspeicheldrüse Entwicklung von verteilten embryonalen Maus-Pankreasvorläuferzellen, einschließlich ihrer erheblichen Ausweitung, Differenzierung und Morphogenese in einem verzweigten Organ. Dieses Verfahren ist zugänglich Bildgebung, funktionelle Störungen und Manipulationen der Nische.

In-vitro-Pankreas Organogenese von Dispersed embryonalen Maus-Vorläufer

The pancreas is an essential organ that regulates glucose homeostasis and secretes digestive enzymes. Research on pancreas embryogenesis has led to the ...

in-vitro-pancreas-organogenesis-from-dispersed-mouse-embryonic

Research

JoVE Journal

Biology

In Vitro Pancreas Organogenesis from Dispersed Mouse Embryonic Progenitors

13.7K Aufrufe.  Swiss Institute for Experimental Cancer Research.  Die in diesem Protokoll beschriebenen dreidimensionalen Kulturverfahren rekapituliert Bauchspeicheldrüse Entwicklung von verteilten embryonalen Maus-Pankreasvorläuferzellen, einschließlich ihrer erheblichen Ausweitung, Differenzierung und Morphogenese in einem verzweigten Organ. Dieses Verfahren ist zugänglich Bildgebung, funktionelle Störungen und Manipulationen der Nische. 

Serie: In Vitro Pancreas Organogenesis from Dispersed Mouse Embryonic Progenitors

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 remain a stem cell or become another type of cell with a more specialized function, This promising of science is leading scientists to investigate the possibility of cell-based therapies to treat disease.

When culture in suspension without antidifferentiation factors, embryonic stem cells spontaneously differentiate and form three-dimensional multicellular aggregates. These cell aggregates are called embryoid bodies(EB). Hanging drop culture is a widely used EB formation induction method. The rounded bottom of hanging drop allows the aggregation of ES cells which can provide mES cells a good environment for forming EBs. The number of ES cells aggregatied in a hanging drop can be controlled by varying the number of cells in the initial cell suspension to be hung as a drop from the lid of Petri dish. Using this method we can reproducibly form homogeneous EBs from a predetermined number of ES cells. 

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

This video demonstrates how to conduct in vitro differentiation of mouse embryonic stem cells to embryoid bodies using the hanging drop method.

In-vitro-Differenzierung von embryonalen Stammzellen der Maus (mES) Zellen unter Verwendung des Hanging-Drop-Methode

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 ...

Forschung

Biologie

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

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of the predominant imaging modalities to assess the restoration of the injured myocardium. Furthermore, ex-vivo labeling agents, such as iron-oxide nanoparticles, have been employed to track and localize the transplanted stem cells. However, this method does not monitor a fundamental cellular biology property regarding the viability of transplanted cells. It has been known that manganese chloride (MnCl2) enters the cells via voltage-gated calcium (Ca2+) channels when the cells are biologically active, and accumulates intracellularly to generate T1 shortening effect. Therefore, we suggest that manganese-guided MRI can be useful to monitor cell viability after the transplantation of hESC into the myocardium.
In this video, we will show how to label hESC with MnCl2 and how those cells can be clearly seen by using MRI in vitro. At the same time, biological activity of Ca2+-channels will be modulated utilizing both Ca2+-channel agonist and antagonist to evaluate concomitant signal changes.

In this video, we are showing how to label human embryonic stem cells (hESC) with manganese chloride (MnCl2) which can enter cells via voltage-gated calcium channels when the cells are biologically active. Additionally, we show the use of MnCl2 as cellular MRI contrast agent to determine the in vitro viability of hESC.

In-vitro-Markierung von humanen embryonalen Stammzellen für Magnetic Resonance Imaging

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of ...

Single-cell Suction Recordings from Mouse Cone Photoreceptors

Rod and cone photoreceptors in the retina are responsible for light detection. In darkness, cyclic nucleotide-gated (CNG) channels in the outer segment are open and allow cations to flow steadily inwards across the membrane, depolarizing the cell. Light exposure triggers the closure of the CNG channels, blocks the inward cation current flow, and thus results in cell hyperpolarization. Based on the polarity of photoreceptors, a suction recording method was developed in 1970s that, unlike the classic patch-clamp technique, does not require penetrating the plasma membrane 1. Drawing the outer segment into a tightly-fitting glass pipette filled with extracellular solution allows recording the current changes in individual cells upon test-flash exposure. However, this well-established "outer-segment-in (OS-in)" suction recording is not suitable for mouse cone recordings, because of the low percentage of cones in the mouse retina (3%) and the difficulties in identifying the cone outer segments. Recently, an inner-segment-in (IS-in) recording configuration was developed to draw the inner segment/nuclear region of the photoreceptor into the recording pipette 2,3. In this video, we will show how to record from individual mouse cone photoresponses using single-cell suction electrode.

We will show how to record flash responses from single mouse cones using a suction electrode.

Einzel-Zell-Saug-Recordings aus Maus Zapfen-Photorezeptoren

Rod and cone photoreceptors in the retina are responsible for light detection. In darkness, cyclic nucleotide-gated (CNG) channels in the outer segment ...

In vivo Imaging and Therapeutic Treatments in an Orthotopic Mouse Model of Ovarian Cancer

Human cancer and response to therapy is better represented in orthotopic animal models. This paper describes the development of an orthotopic mouse model of ovarian cancer, treatment of cancer via oral delivery of drugs, and monitoring of tumor cell behavior in response to drug treatment in real time using in vivo imaging system. In this orthotopic model, ovarian tumor cells expressing luciferase are applied topically by injecting them directly into the mouse bursa where each ovary is enclosed. Upon injection of D-luciferin, a substrate of firefly luciferase, luciferase-expressing cells generate bioluminescence signals. This signal is detected by the in vivo imaging system and allows for a non-invasive means of monitoring tumor growth, distribution, and regression in individual animals. Drug administration via oral gavage allows for a maximum dosing volume of 10 mL/kg body weight to be delivered directly to the stomach and closely resembles delivery of drugs in clinical treatments. Therefore, techniques described here, development of an orthotopic mouse model of ovarian cancer, oral delivery of drugs, and in vivo imaging, are useful for better understanding of human ovarian cancer and treatment and will improve targeting this disease.

In vivo Imaging and Therapeutic Treatments in an Orthotopic Mouse Model of Ovarian Cancer

Orthotopic animal models of ovarian cancer replicate better human disease and therefore enhance our understanding of cancer progression and tumor response to therapy. A mouse model receives an intrabursal injection of luciferase-expressing ovarian tumor cells. Treatment is administered via oral gavage. Tumor growth is monitored by in vivo imaging system.

In-vivo-Imaging und therapeutische Behandlungen in einem orthotopen Mausmodell des Eierstockkrebs

Human cancer and response to therapy is better represented in orthotopic animal models.  This paper describes the development of an orthotopic mouse model ...

Purification of Progenitors from Skeletal Muscle

Skeletal muscle contains multiple progenitor populations of distinct embryonic origins and developmental potential. Myogenic progenitors, usually residing in a "satellite cell position" between the myofiber plasma membrane and the laminin-rich basement membrane that ensheaths it, are self-renewing cells that are solely committed to the myogenic lineage1,2. We have recently described a second class of vessel associated progenitors that can generate myofibroblasts and white adipocytes, which responds to damage by efficiently entering proliferation and provides trophic support to myogenic cells during tissue regeneration3,4. One of the most trusted assays to determine the developmental and regenerative potential of a given cell population relies on their isolation and transplantation5-7. To this end we have optimized protocols for their purification by flow cytometry from enzymatically dissociated muscle, which we will outline in this article. The populations obtained using this method will contain either myogenic or fibro/adipogenic colony forming cells: no other cell types are capable of expanding in vitro or surviving in vivo delivery. However, when these populations are used immediately after the sort for molecular analysis (e.g qRT-PCR) one must keep in mind that the freshly sorted subsets may contain other contaminant cells that lack the ability of forming colonies or engrafting recipients.

Method for the enzymatic dissociation, surface labeling and purification by flow cytometry of fibro/adipogenic and myogenic progenitors from murine skeletal muscle.

Reinigung von Vorläufern aus Skelettmuskeln

Skeletal muscle contains multiple progenitor populations of distinct embryonic origins and developmental potential. Myogenic progenitors, usually residing ...

A System for ex vivo Culturing of Embryonic Pancreas

The pancreas controls vital functions of our body, including the production of digestive enzymes and regulation of blood sugar levels1. Although in the past decade many studies have contributed to a solid foundation for understanding pancreatic organogenesis, important gaps persist in our knowledge of early pancreas formation2. A complete understanding of these early events will provide insight into the development of this organ, but also into incurable diseases that target the pancreas, such as diabetes or pancreatic cancer. Finally, this information will generate a blueprint for developing cell-replacement therapies in the context of diabetes.
 During embryogenesis, the pancreas originates from distinct embryonic outgrowths of the dorsal and ventral foregut endoderm at embryonic day (E) 9.5 in the mouse embryo3,4. Both outgrowths evaginate into the surrounding mesenchyme as solid epithelial buds, which undergo proliferation, branching and differentiation to generate a fully mature organ2,5,6. Recent evidences have suggested that growth and differentiation of pancreatic cell lineages, including the insulin-producing &beta;-cells, depends on proper tissue-architecture, epithelial remodeling and cell positioning within the branching pancreatic epithelium7,8. However, how branching morphogenesis occurs and is coordinated with proliferation and differentiation in the pancreas is largely unknown. This is in part due to the fact that current knowledge about these developmental processes has relied almost exclusively on analysis of fixed specimens, while morphogenetic events are highly dynamic.
 Here, we report a method for dissecting and culturing mouse embryonic pancreatic buds ex vivo on glass bottom dishes, which allow direct visualization of the developing pancreas (Figure 1). This culture system is ideally devised for confocal laser scanning microscopy and, in particular, live-cell imaging. Pancreatic explants can be prepared not only from wild-type mouse embryos, but also from genetically engineered mouse strains (e.g. transgenic or knockout), allowing real-time studies of mutant phenotypes. Moreover, this ex vivo culture system is valuable to study the effects of chemical compounds on pancreatic development, enabling to obtain quantitative data about proliferation and growth, elongation, branching, tubulogenesis and differentiation. In conclusion, the development of an ex vivo pancreatic explant culture method combined with high-resolution imaging provides a strong platform for observing morphogenetic and differentiation events as they occur within the developing mouse embryo.

A System for ex vivo Culturing of Embryonic Pancreas

Here, we describe a method for isolation, culture and manipulation of mouse embryonic pancreas. This represents an excellent ex vivo system for studying various aspects of pancreatic development, including morphogenesis, differentiation and growth. Pancreatic bud explants can be cultured for several days and used in a range of different applications, including whole-mount immunofluorescence and live imaging.

Ein System für<em&gt; Ex vivo</em&gt; Kultivierung von embryonalen Pankreas

The pancreas controls vital functions of our body,  including the production of digestive enzymes and regulation of blood sugar  levels1. Although in the ...

Generation of Mice Derived from Induced Pluripotent Stem Cells

The production of induced pluripotent stem cells (iPSCs) from somatic cells provides a means to create valuable tools for basic research and may also produce a source of patient-matched cells for regenerative therapies. iPSCs may be generated using multiple protocols and derived from multiple cell sources. Once generated, iPSCs are tested using a variety of assays including immunostaining for pluripotency markers, generation of three germ layers in embryoid bodies and teratomas, comparisons of gene expression with embryonic stem cells (ESCs) and production of chimeric mice with or without germline contribution2. Importantly, iPSC lines that pass these tests still vary in their capacity to produce different differentiated cell types2. This has made it difficult to establish which iPSC derivation protocols, donor cell sources or selection methods are most useful for different applications.
The most stringent test of whether a stem cell line has sufficient developmental potential to generate all tissues required for survival of an organism (termed full pluripotency) is tetraploid embryo complementation (TEC)3-5. Technically, TEC involves electrofusion of two-cell embryos to generate tetraploid (4n) one-cell embryos that can be cultured in vitro to the blastocyst stage6. Diploid (2n) pluripotent stem cells (e.g. ESCs or iPSCs) are then injected into the blastocoel cavity of the tetraploid blastocyst and transferred to a recipient female for gestation (see Figure 1). The tetraploid component of the complemented embryo contributes almost exclusively to the extraembryonic tissues (placenta, yolk sac), whereas the diploid cells constitute the embryo proper, resulting in a fetus derived entirely from the injected stem cell line.
Recently, we reported the derivation of iPSC lines that reproducibly generate adult mice via TEC1. These iPSC lines give rise to viable pups with efficiencies of 5-13%, which is comparable to ESCs3,4,7 and higher than that reported for most other iPSC lines8-12. These reports show that direct reprogramming can produce fully pluripotent iPSCs that match ESCs in their developmental potential and efficiency of generating pups in TEC tests. At present, it is not clear what distinguishes between fully pluripotent iPSCs and less potent lines13-15. Nor is it clear which reprogramming methods will produce these lines with the highest efficiency. Here we describe one method that produces fully pluripotent iPSCs and "all- iPSC" mice, which may be helpful for investigators wishing to compare the pluripotency of iPSC lines or establish the equivalence of different reprogramming methods.

Generating induced pluripotent stem cell (iPSC) lines produces lines of differing developmental potential even when they pass standard tests for pluripotency. Here we describe a protocol to produce mice derived entirely from iPSCs, which defines the iPSC lines as possessing full pluripotency1.

Generation der Mäuse aus induzierten pluripotenten Stammzellen

The production of induced pluripotent stem cells (iPSCs) from somatic cells provides a means to create valuable tools for basic research and may also ...

RNA Isolation from Mouse Pancreas: A Ribonuclease-rich Tissue

Isolation of high-quality RNA from ribonuclease-rich tissue such as mouse pancreas presents a challenge. As a primary function of the pancreas is to aid in digestion, mouse pancreas may contain as much a 75 mg of ribonuclease. We report modifications of standard phenol/guanidine thiocyanate lysis reagent protocols to isolate RNA from mouse pancreas. Guanidine thiocyanate is a strong protein denaturant and will effectively disrupt the activity of ribonuclease under most conditions. However, critical modifications to standard protocols are necessary to successfully isolate RNA from ribonuclease-rich tissues. Key steps include a high lysis reagent to tissue ratio, removal of undigested tissue prior to phase separation and inclusion of a ribonuclease inhibitor to the RNA solution. Using these and other modifications, we routinely isolate RNA with RNA Integrity Number (RIN) greater than 7. The isolated RNA is of suitable quality for routine gene expression analysis. Adaptation of this protocol to isolate RNA from ribonuclease rich tissues besides the pancreas should be readily achievable.

We report a procedure to isolate RNA with high integrity from the ribonuclease rich mouse pancreas.

RNA-Isolierung aus Maus Pankreas: Eine Ribonuklease-reichen Gewebe

Isolation of high-quality RNA from ribonuclease-rich tissue such as mouse pancreas presents a challenge.  As a primary function of the pancreas is to aid ...

Protein Isolation from the Developing Embryonic Mouse Heart Valve Region

Western blot analysis is a commonly employed technique for detecting and quantifying protein levels. However, for small tissue samples, this analysis method may not be sufficiently sensitive to detect a protein of interest. To overcome these difficulties, we examined protocols for obtaining protein from adult human cardiac valves and modified these protocols for the developing early embryonic mouse counterparts. In brief, the mouse embryonic aortic valve regions, including the aortic valve and surrounding aortic wall, are collected in the minimal possible volume of a Tris-based lysis buffer with protease inhibitors. If required based on the breeding strategy, embryos are genotyped prior to pooling four embryonic aortic valve regions for homogenization. After homogenization, an SDS-based sample buffer is used to denature the sample for running on an SDS-PAGE gel and subsequent western blot analysis. Although the protein concentration remains too low to quantify using spectrophotometric protein quantification assays and have sample remaining for subsequent analyses, this technique can be used to successfully detect and semi-quantify phosphorylated proteins via western blot from pooled samples of four embryonic day 13.5 mouse aortic valve regions, each of which yields approximately 1 &#956;g of protein. This technique will be of benefit for studying cell signaling pathway activation and protein expression levels during early embryonic mouse valve development.

The analysis of protein expression in young embryonic mouse valves has been hampered by the limited tissue available. This manuscript provides a protocol for preparing protein from developing embryonic mouse valve regions for western blot analysis.

Proteinisolierung aus den Entwicklungs embryonalen Mäuseherzklappen Region

Western blot analysis is a commonly employed technique for detecting and quantifying protein levels. However, for small tissue samples, this analysis ...

Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used as manufacturing platforms for added-value products such as biopharmaceuticals. In both cases, liquid plant extracts may need to be clarified to remove particulates. Optimal clarification reduces the costs of filtration and centrifugation by increasing capacity and longevity. This can be achieved by introducing charged polymers known as flocculants, which cross-link dispersed particles to facilitate solid-liquid separation. There are no mechanistic flocculation models for complex mixtures such as plant extracts so empirical models are used instead. Here a design-of-experiments procedure is described that allows the rapid screening of different flocculants, optimizing the clarification of plant extracts and significantly reducing turbidity. The resulting predictive models allow the identification of robust process conditions and sets of polymers with complementary properties, e.g. effective flocculation in extracts with specific conductivities. The results presented for tobacco leaf extracts can easily be adapted to other plant species or tissues and will thus facilitate the development of more cost-effective downstream processes for commodities and plant-derived pharmaceuticals.

The design-of-experiments procedure presented here allows the evaluation of different flocculants in terms of their ability to aggregate dispersed particles in plant extracts, thus reducing turbidity and the costs of downstream processing.

Vorgehensweise Um die Effizienz von Flockungsmittel für die Beseitigung von Dispersed Partikel aus Pflanzenextrakten zur Bewertung

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used ...