PWD wird von einem kanadischen Institutes of Health Research Fellowship (CIHR) und einen Zuschuss für CIHR Gerald M. Kidder bei Western University unterstützt. Der Autor möchte auch Julang Li an der University of Guelph bestätigen für die Hilfe bei der Entwicklung des hier vorgestellten Protokoll.

1. Nährmedienzubereitung <ol><li> Bereiten Medien 2-3 Stunden im Voraus über die Verwendung und Ort mit einem gelockerten Kappe in der Zellkulturbrutschrank wo das Experiment stattfindet. Medien in der vorliegenden Protokoll verwendet: <ol><li> Bereiten Stammzellen, das aus DMEM/F12 mit 1 x B27, 40 ng / ml bFGF und 20 ng / ml EGF ergänzt. </li><li> Bereiten Keim Zelldifferenzierungsmedium bestehend aus M199 mit 0,05 IU FSH, LH 0,03 IU, 3 mg / ml BSA, 5 ul / ml ITS, 0,23 mM Natriumpyruvat, 1 mg / ml Fetuin und 1 ng / ml EGF ergänzt. Eine Basis, das aus allen Zusatzstoffen, jedoch unter Weglassen FSH, LH und EGF kann hergestellt und gelagert bei 4 ° C für bis zu einer Woche. </li></ol></li></ol> 2. Stem Cell Culture Vorbereitung <ol><li> Isolieren Stammzellen aus neugeborenen Maus Welpen wie zuvor beschrieben 12. Nutzen Stammzellen bei Passage 2-4 für die in vitro Differenzierung Keimzelle. Der WirkungsgradOLC Bildung direkt mit der Qualität der Ausgangsstoffe Stammzellen verbunden. Am besten ist es, die Differenzierung, sobald die Bevölkerung sauber und gesund erscheint, das ist in der Regel bei rund Durchgang 2 zu starten. Weitere Kultivierung der Stammzellen letzten Durchgang 2 wirkt sich negativ auf die Effizienz OLC Bildung (unveröffentlichte Ergebnisse). </li><li> 48 Stunden vor Beginn der Differenzierung Subkultur die Stammzellen. Entfernen Sie alle suspendiert kugelförmige Zellaggregate und verbrachte Medien aus der Kulturschale mit einer serologischen Pipette und in eine 15 ml Tube. Es ist wichtig zu erfassen nur die suspendierten sphärische Aggregate von Zellen und die Zellen nicht an der Unterseite der Schale, die spontan differenzierenden. </li><li> Pellet die Zellen bei 500 xg für 5 min., Den Überstand verwerfen und Resuspension in 500 ml frisches Stammzell-Medien erwärmt auf 37 ° C. Gently Pipette die Aggregate teilweise distanzieren die Zellen. Nicht aggressiv Pipette in die Zelles, da dies die Lebensfähigkeit der Zellen zu reduzieren. Waschen Sie die teilweise dissoziierten Zellen in 9,5 ml frischem vorgewärmten Stammzell-Medium auf einem niedrigen Aufsatz 10 cm Zellkulturschale. </li><li> Liefert die Zellen auf eine 37 ° C, 5% CO 2 Inkubator für Zellkulturen 48 Stunden vor Beginn der Differenzierung. </li></ol> 3. OLC Differenzierung <ol><li> Mit einer serologischen Pipette entfernen Sie die Stammzellen aus der Kulturschale und in einen 15-ml-Tube, hinter alle angeschlossenen Zellen zu verlassen. Pellet die Zellen bei 500 xg und Resuspendieren in 500 ul sterilem PBS. Kräftige Pipette die Zellen mit einer breiten Bohrung 1.000 ul Spitze in Klumpen nicht größer als 10-20 Zellen. Entfernen Sie regelmäßig eine kleine Menge von Zellen, während Dissoziation, und überprüfen unter einem weißen Lichtmikroskop zu bestätigen aggregierten Zellen sind in Klumpen von 10-20 einzelnen Zellen. Über Dissoziation führt zu verminderter Lebensfähigkeit der Zellen führen. </li><li> In 9,5 ml PBS zu den dissoziierten Zellen und fügen Sie 15 ul dieser Zellsuspension auf eine Zählkammer zur Zellzählung. Pellet die Zellen bei 500 xg für 5 min. </li><li> Resuspendieren der Zellen in einer Konzentration von 1.32X10 6 Zellen / ml in Differenzierungsmedium. </li><li> Platte die Zellen durch Zugabe von 500 ul pro Well in eine 24-Well-Flachboden Suspension Gericht. </li><li> Legen Sie die 24 Well-Platte in einer Zellkultur-Inkubator bei 37 ° C in 5% CO 2 für 48 Stunden. Entfernen 250 ul Medium aus jedem Well entnommen und in einen entsprechend gekennzeichneten 1,5 ml Tube. In 250 ul frisch Differenzierung Medium in jede Vertiefung. Zentrifuge das verbrauchte Medium bei 500 xg für 5 min. und den Überstand verwerfen. Resuspendieren keine pelletierten Zellen in 50 ul frisch Differenzierung Medium und auf die entsprechende Kultur auch auf die Differenzierung Platte. </li><li> Jede 48 Stunden verändern Hälfte des Mediums bis zum Tag 12 der Differenzierung. </li></ol>

<ol>
	<li>van den Hurk, R., Zhao, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+mammalian+oocytes+and+their+growth,+differentiation+and+maturation+within+ovarian+follicles.">Formation of mammalian oocytes and their growth, differentiation and maturation within ovarian follicles.</a> Theriogenology. 63, 1717-1751 (2005).</li><li>Molyneaux, K. A., Stallock, J., Schaible, K., Wylie, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time-lapse+analysis+of+living+mouse+germ+cell+migration.">Time-lapse analysis of living mouse germ cell migration.</a> Dev. Biol. 240, 488-498 (2001).</li><li>Lawson, K. A., Hage, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clonal+analysis+of+the+origin+of+primordial+germ+cells+in+the+mouse.">Clonal analysis of the origin of primordial germ cells in the mouse.</a> Ciba Found Symp. 182, 68-91 (1994).</li><li>Ginsburg, M., Snow, M. H., McLaren, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Primordial+germ+cells+in+the+mouse+embryo+during+gastrulation.">Primordial germ cells in the mouse embryo during gastrulation.</a> Development. 110, 521-528 (1990).</li><li>Hubner, K., Fuhrmann, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Derivation+of+oocytes+from+mouse+embryonic+stem+cells.">Derivation of oocytes from mouse embryonic stem cells.</a> Science. 300, 1251-1256 (2003).</li><li>Toyooka, Y., Tsunekawa, N., Akasu, R., Noce, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Embryonic+stem+cells+can+form+germ+cells+in+vitro.">Embryonic stem cells can form germ cells in vitro.</a> Proc. Natl. Acad. Sci. U.S.A. 100, 11457-11462 (2003).</li><li>Wang, L., Cao, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oocyte-like+Cells+Induced+from+Mouse+Spermatogonial+Stem+Cells.">Oocyte-like Cells Induced from Mouse Spermatogonial Stem Cells.</a> Cell Biosci. 2, 27 (2012).</li><li>Dyce, P. W., Wen, L., Li, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+germline+potential+of+stem+cells+derived+from+fetal+porcine+skin.">In vitro germline potential of stem cells derived from fetal porcine skin.</a> Nat. Cell Biol. 8, 384-390 (2006).</li><li>Danner, S., Kajahn, J., Geismann, C., Klink, E., Kruse, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Derivation+of+oocyte-like+cells+from+a+clonal+pancreatic+stem+cell+line.">Derivation of oocyte-like cells from a clonal pancreatic stem cell line.</a> Mol. Hum. Reprod. 13, 11-20 (2007).</li><li>Cheng, X., Chen, S., Yu, X., Zheng, P., Wang, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=BMP15+gene+is+activated+during+human+amniotic+fluid+stem+cell+differentiation+into+oocyte-like+cells.">BMP15 gene is activated during human amniotic fluid stem cell differentiation into oocyte-like cells.</a> DNA Cell Biol. 31, 1198-1204 (2012).</li><li>Song, S. H., Kumar, B. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+porcine+multipotent+stem/stromal+cells+derived+from+skin,+adipose,+and+ovarian+tissues+and+their+differentiation+in+vitro+into+putative+oocyte-like+cells.">Characterization of porcine multipotent stem/stromal cells derived from skin, adipose, and ovarian tissues and their differentiation in vitro into putative oocyte-like cells.</a> Stem Cells Dev. 20, 1359-1370 (2011).</li><li>Dyce, P. W., Liu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+and+in+vivo+germ+line+potential+of+stem+cells+derived+from+newborn+mouse+skin.">In vitro and in vivo germ line potential of stem cells derived from newborn mouse skin.</a> PLoS One. 6, e20339 (2011).</li><li>Linher, K., Dyce, P., Li, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Primordial+germ+cell-like+cells+differentiated+in+vitro+from+skin-derived+stem+cells.">Primordial germ cell-like cells differentiated in vitro from skin-derived stem cells.</a> PLoS One. 4, e8263 (2009).</li><li>Hayashi, K., Ogushi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Offspring+from+Oocytes+Derived+from+in+Vitro+Primordial+Germ+Cell-Like+Cells+in+Mice.">Offspring from Oocytes Derived from in Vitro Primordial Germ Cell-Like Cells in Mice.</a> Science. , (2012).</li></ol>

Keine Interessenskonflikte erklärt.

Um funktionelle OLCs bisher nicht entwickelt worden, mit einer komplett in-vitro-Assay. Vor kurzem wurde eine Studie von Hayashi et al. Konnte Nachkommen von PGC-ähnlichen Zellen in vitro gebildet und übertragen in vivo für die weitere Entwicklung 14 produzieren. Beginnend mit ES-Zellen oder induzierten pluripotenten Zellen konnten sie PGC wie Zellen, die, wenn nach in vivo Transplantation erholt bilden konnten gereift, befruchtet werden, und verwendet werden, u...

Während der frühen Embryogenese kommt Gametogenese durch eine Reihe von Stufen einschließlich Urkeimzelle (PGC) Bildung, Migration und schließlich Kolonisierung der Gonaden Grate. Während dieser Zeit PGCs unterziehen Proliferation und Differenzierung in immer mehr reifen Gameten 1. Die Tatsache, dass PGCs von der Basis der Allantois in den Embryo Enddarm und schließlich entlang der dorsalen Wand schließlich Kolonisierung der Gonaden Grate migrieren macht sie außerordentlich schwierig, 2 studieren. Trotz der Fortschritte in diesem Bereich, haben Studien versuchen, PGC Bildung und Differenzierung zu verstehen durch ihre begrenzte Anzahl, Lage und wandernde 3,4 behindert worden. In den letzten Jahren embryonalen Stammzellen haben gezeigt, dass das Potential, Keimzellen in vitro 5,6 bilden. In ähnlicher Weise wurden verschiedene somatische Stammzellen auch gezeigt, dass das Potential zur Bildung von Keimzellen foll habenwegen in vitro Kultivierung 7-11. Kürzlich Stammzellen aus der Haut von Mäusen isoliert Neugeborenen wurden in vitro in Keim-ähnlichen Zellen und frühen Oozyten 12 differenziert. Während der Differenzierung die Teilmenge der Stammzellen exprimiert Oct4 erhöht und ähnlichen Strukturen Cumulus-Oozyten-Komplexe gebildet wurden. Die Oozyten-ähnliche Zellen (OLC) aus den Kulturen aufgenommen und im Vergleich zu natürlichen Oozyten. Mit dieser Kultur Verfahren OLCs Messung 40-45 um erhalten, dass express ähnliche Markierungen, um Eizellen wie Gdf9b, VASA und DAZL. Bis heute bleiben die resultierenden OLCs nicht fällig oder befruchtete 12. Obwohl die OLCs bleiben nicht in der Lage zu funktionieren, das Protokoll verwendet, um diese OLCs bilden können noch Nutzen als Test, um die Entstehung und Entwicklung des früheren Stadium Keimzellen innerhalb studieren ein in vitro System geschlossen. Die ursprüngliche Veröffentlichung diskutieren die Bildung von so OLCsmatic Stammzellen genutzt fetalen Schweinehaut als Stammzell-Quelle 8. Aufbauend auf dieser Studie die PGC-ähnlichen Zellen früh während induzierte Differenzierung gebildet wurde gezeigt, dass die Vorstufen der OLCs und Eil wie PGC Marker als OCT4, VASA, STELLA, C-KIT und DAZL 13. Diese Daten unterstützen das Potenzial der Verwendung dieses Systems zu Keimzellbildung und Differenzierung in vitro zu untersuchen. Das Protokoll verwendet werden, um OLCs aus neugeborenen Maus Haut bilden wird in diesem Video-Artikel gezeigt werden. Dieses Protokoll bietet ein in vitro Modell zur Keimzelle Entwicklung, die ein Mittel zur Aufklärung wichtige Faktoren für die Proliferation und Differenzierung bieten kann studieren.

<table border="1">
		<tbody>
		 <tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		 </tr>
		 <tr>
			<td>DMEM/F12</td>
			<td>Invitrogen</td>
			<td>12500</td>
			<td></td>
		 </tr>
		 <tr>
			<td>B27</td>
			<td>Invitrogen</td>
			<td>17504044</td>
			<td></td>
		 </tr>
		 <tr>
			<td>EGF</td>
			<td>Invitrogen</td>
			<td>PHG0311</td>
			<td></td>
		 </tr>
		 <tr>
			<td>bFGF</td>
			<td>Invitrogen</td>
			<td>PHG0266</td>
			<td></td>
		 </tr>
		 <tr>
			<td>ITS</td>
			<td>Invitrogen</td>
			<td>41400-045</td>
			<td></td>
		 </tr>
		 <tr>
			<td>BSA</td>
			<td>Sigma</td>
			<td>A-6003</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Sodium Pyruvate</td>
			<td>Invitrogen</td>
			<td>11360-070</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Fetuin</td>
			<td>Sigma</td>
			<td>F3385</td>
			<td></td>
		 </tr>
		 <tr>
			<td>FSH</td>
			<td>Sioux Biochemicals</td>
			<td>915</td>
			<td></td>
		 </tr>
		 <tr>
			<td>LH</td>
			<td>Sioux Biochemicals</td>
			<td>925</td>
			<td></td>
		 </tr>
		 <tr>
			<td>M199</td>
			<td>Invitrogen</td>
			<td>31100-035</td>
			<td></td>
		 </tr>
		 <tr>
			<td>24 well plates</td>
			<td>Nunc</td>
			<td>144530</td>
			<td></td>
		 </tr>
		 <tr>
			<td>10 cm dishes</td>
			<td>VWR</td>
			<td>25384-088</td>
			<td></td>
		 </tr>
		 <tr>
			<td>15 ml tubes</td>
			<td>BD</td>
			<td>352095</td>
			<td></td>
		 </tr>
		</tbody>
 </table>

differentiation of newborn mouse skin derived stem cells into germ-like cells in vitro

Studieren Keimzellbildung und Differenzierung ist traditionell sehr schwierig aufgrund der geringen Zellzahlen und ihre Lage tief in sich entwickelnden Embryonen. Die Verfügbarkeit eines &quot;geschlossenen&quot; in vitro System könnte von unschätzbarem Wert für unser Verständnis der Gametogenese. Die Bildung der Eizelle-ähnlichen Zellen (OLC) von somatischen Stammzellen, aus neugeborenen Maus Haut isoliert, hat sich gezeigt und visualisiert werden in diesem Video-Protokoll. Die resultierenden OLCs auszudrücken verschiedenen Markern im Einklang mit Eizellen wie Oct4, Vasa, BMP15 und SCP3. Allerdings bleiben sie nicht in der Lage, um die Reifung oder Befruchtung aufgrund eines Fehlers zu vervollständigen Meiose durchlaufen. Dieses Protokoll wird ein System, das nützlich für die Untersuchung der frühen Bildung und Differenzierung von Keimzellen in reifer Keimzellen ist. Während der frühen Differenzierung die Anzahl der Zellen, die Oct4 (potentiellen Keim-ähnlichen Zellen) erreicht ~ 5%, jedoch derzeit die formation von OLCs bleibt relativ ineffizient. Das Protokoll ist relativ geradlinig, aber auch besondere Vorsicht geboten, um sicherzustellen, dass die ab-Zell-Population ist gesund und in einer frühen Passage werden.

Zunächst werden die Zellen auf der Kulturschale Boden anlagern und ausbreiten. Bei 42-72 h in Differenzierung kleine suspendiert OCT4 positive Zellen zu bilden und vermehren (Abbildung 1A). Kurz nach der Visualisierung dieser Zellen die Mehrheit wird verschwinden und die anhaftenden Zellen entsteht dichter Kolonie Aggregate auf die Kultur Boden zu bilden. Nach ein paar Tagen wird diese Aggregate aus der Kultur Oberfläche lösen. In einigen dieser Aggregate eine große Zelle zu beobachten (Abb....

Watch this Scientific Journal Video about Differentiation of Newborn Mouse Skin Derived Stem Cells into Germ-like Cells In vitro at JoVE.com

Differentiation of Newborn Mouse Skin Derived Stem Cells into Germ-like Cells In vitro

In den letzten Jahren ist die Bildung von Keimzellen mit in-vitro-Kultur Methoden nachgewiesen wurde mit mehreren verschiedenen Arten von somatischen Stammzellen. Dieser Artikel wird visuell präsentieren die Differenzierung der neugeborenen Maus-Stammzellen zu frühen Oozyten-ähnlichen Zellen.

Differenzierung von Newborn Mäusehaut Derived Stem Cells in Germ-like Cells<em&gt; In-vitro-</em

Studying  germ cell formation and differentiation has traditionally been very difficult  due to low cell numbers and their location deep within developing ...

differentiation-newborn-mouse-skin-derived-stem-cells-into-germ-like

Research

JoVE Journal

Biology

Differentiation of Newborn Mouse Skin Derived Stem Cells into Germ-like Cells In vitro

9.2K Aufrufe.  The University of Western Ontario. In den letzten Jahren ist die Bildung von Keimzellen mit in-vitro-Kultur Methoden nachgewiesen wurde mit mehreren verschiedenen Arten von somatischen Stammzellen. Dieser Artikel wird visuell präsentieren die Differenzierung der neugeborenen Maus-Stammzellen zu frühen Oozyten-ähnlichen Zellen.

Serie: Differentiation of Newborn Mouse Skin Derived Stem Cells into Germ-like Cells In vitro

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

Differentiation of Embryonic Stem Cells into Oligodendrocyte Precursors

Oligodendrocytes are the myelinating cells of the central nervous system. For regenerative cell therapy in demyelinating diseases, there is significant interest in deriving a pure population of lineage-committed oligodendrocyte precursor cells (OPCs) for transplantation. OPCs are characterized by the activity of the transcription factor Olig2 and surface expression of a proteoglycan NG2. Using the GFP-Olig2 (G-Olig2) mouse embryonic stem cell (mESC) reporter line, we optimized conditions for the differentiation of mESCs into GFP+Olig2+NG2+ OPCs. In our protocol, we first describe the generation of embryoid bodies (EBs) from mESCs. Second, we describe treatment of mESC-derived EBs with small molecules: (1) retinoic acid (RA) and (2) a sonic hedgehog (Shh) agonist purmorphamine (Pur) under defined culture conditions to direct EB differentiation into the oligodendroglial lineage. By this approach, OPCs can be obtained with high efficiency (&gt;80%) in a time period of 30 days. Cells derived from mESCs in this protocol are phenotypically similar to OPCs derived from primary tissue culture. The mESC-derived OPCs do not show the spiking property described for a subpopulation of brain OPCs in situ. To study this electrophysiological property, we describe the generation of spiking mESC-derived OPCs by ectopically expressing NaV1.2 subunit. The spiking and nonspiking cells obtained from this protocol will help advance functional studies on the two subpopulations of OPCs.

We describe a small molecule-based protocol for differentiation of mouse embryonic stem cells into oligodendrocyte precursor cells (OPCs). This protocol generates Olig2+NG2+ OPCs with high efficiency by 30 days of differentiation. We also describe a method to generate "spiking" OPCs that can fire action potentials.

Differenzierung von embryonalen Stammzellen in Oligodendrozyten Precursors

Oligodendrocytes are the myelinating cells of the central nervous system. For regenerative cell therapy in demyelinating diseases, there is significant ...

Reprogramming Human Somatic Cells into Induced Pluripotent Stem Cells (iPSCs) Using Retroviral Vector with GFP

Human embryonic stem cells (hESCs) are pluripotent and an invaluable cellular sources for in vitro disease modeling and regenerative medicine1. It has been previously shown that human somatic cells can be reprogrammed to pluripotency by ectopic expression of four transcription factors (Oct4, Sox2, Klf4 and Myc) and become induced pluripotent stem cells (iPSCs)2-4 . Like hESCs, human iPSCs are pluripotent and a potential source for autologous cells. Here we describe the protocol to reprogram human fibroblast cells with the four reprogramming factors cloned into GFP-containing retroviral backbone4. Using the following protocol, we generate human iPSCs in 3-4 weeks under human ESC culture condition. Human iPSC colonies closely resemble hESCs in morphology and display the loss of GFP fluorescence as a result of retroviral transgene silencing. iPSC colonies isolated mechanically under a fluorescence microscope behave in a similar fashion as hESCs. In these cells, we detect the expression of multiple pluripotency genes and surface markers.

Reprogramming Human Somatic Cells into Induced Pluripotent Stem Cells iPSCs Using Retroviral Vector with GFP

A method to generate human induced pluripotent stem cells (iPSCs) via retrovirus-mediated ectopic expression of OCT4, SOX2, KLF4 and MYC is described. A practical way to identify human iPSC colonies based on GFP expression is also discussed.

Reprogrammierung menschlichen Körperzellen in induzierte pluripotente Stammzellen (IPSCs) mit retroviralen Vektoren mit GFP

Human embryonic stem cells (hESCs) are pluripotent and an invaluable cellular sources for in vitro disease modeling and regenerative medicine1. It has ...

Efficient Differentiation of Mouse Embryonic Stem Cells into Motor Neurons

Direct differentiation of embryonic stem (ES) cells into functional motor neurons represents a promising resource to study disease mechanisms, to screen new drug compounds, and to develop new therapies for motor neuron diseases such as spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS). Many current protocols use a combination of retinoic acid (RA) and sonic hedgehog (Shh) to differentiate mouse embryonic stem (mES) cells into motor neurons1-4. However, the differentiation efficiency of mES cells into motor neurons has only met with moderate success. We have developed a two-step differentiation protocol5 that significantly improves the differentiation efficiency compared with currently established protocols. The first step is to enhance the neuralization process by adding Noggin and fibroblast growth factors (FGFs). Noggin is a bone morphogenetic protein (BMP) antagonist and is implicated in neural induction according to the default model of neurogenesis and results in the formation of anterior neural patterning6. FGF signaling acts synergistically with Noggin in inducing neural tissue formation by promoting a posterior neural identity7-9. In this step, mES cells were primed with Noggin, bFGF, and FGF-8 for two days to promote differentiation towards neural lineages. The second step is to induce motor neuron specification. Noggin/FGFs exposed mES cells were incubated with RA and a Shh agonist, Smoothened agonist (SAG), for another 5 days to facilitate motor neuron generation. To monitor the differentiation of mESs into motor neurons, we used an ES cell line derived from a transgenic mouse expressing eGFP under the control of the motor neuron specific promoter Hb91. Using this robust protocol, we achieved 51&plusmn;0.8% of differentiation efficiency (n = 3; p &lt; 0.01, Student's t-test)5. Results from immunofluorescent staining showed that GFP+ cells express the motor neuron specific markers, Islet-1 and choline acetyltransferase (ChAT). Our two-step differentiation protocol provides an efficient way to differentiate mES cells into spinal motor neurons.

We developed a new protocol to improve efficiency of in vitro differentiation of mouse embryonic stem cells into motor neurons. The differentiated ES cells acquired motor neurons features as evidenced by expression of neuronal and motor neuron markers using immunohistochemical techniques.

Effiziente Differenzierung von embryonalen Stammzellen der Maus in Motoneuronen

Direct differentiation of embryonic stem (ES) cells into functional  motor neurons represents a promising resource to study disease mechanisms, to  screen ...

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 ...

Induction and Analysis of Epithelial to Mesenchymal Transition

Epithelial to mesenchymal transition (EMT) is essential for proper morphogenesis during development. Misregulation of this process has been implicated as a key event in fibrosis and the progression of carcinomas to a metastatic state. Understanding the processes that underlie EMT is imperative for the early diagnosis and clinical control of these disease states. Reliable induction of EMT in vitro is a useful tool for drug discovery as well as to identify common gene expression signatures for diagnostic purposes. Here we demonstrate a straightforward method for the induction of EMT in a variety of cell types. Methods for the analysis of cells pre- and post-EMT induction by immunocytochemistry are also included. Additionally, we demonstrate the effectiveness of this method through antibody-based array analysis and migration/invasion assays.

A straightforward method is described for the induction of epithelial to mesenchymal transition (EMT) in a variety of cell types. Methods for the analysis of cells in EMT states by immunocytochemistry are included.

Induktion und Analyse von epithelialen zu mesenchymalen Transition

Epithelial  to mesenchymal transition (EMT) is essential for proper morphogenesis during  development. Misregulation of this  process has been implicated ...

Nephrotoxin Microinjection in Zebrafish to Model Acute Kidney Injury

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid decline in renal function and development of the clinical syndrome known as acute kidney injury (AKI). Pharmacological agents used to treat medical circumstances ranging from bacterial infection to cancer, when administered individually or in combination with other drugs, can initiate AKI. Zebrafish are a useful animal model to study the chemical effects on renal function in vivo, as they form an embryonic kidney comprised of nephron functional units that are conserved with higher vertebrates, including humans. Further, zebrafish can be utilized to perform genetic and chemical screens, which provide opportunities to elucidate the cellular and molecular facets of AKI and develop therapeutic strategies such as the identification of nephroprotective molecules. Here, we demonstrate how microinjection into the zebrafish embryo can be utilized as a paradigm for nephrotoxin studies.

Renal injuries incurred from nephrotoxins, which include drugs ranging from antibiotics to chemotherapeutics, can result in complex disorders whose pathogenesis remains incompletely understood. This protocol demonstrates how zebrafish can be used for disease modeling of these conditions, which can be applied to the identification of renoprotective measures.

Nephrotoxin Mikroinjektion in Zebrabärbling akuten Nierenschädigung zu Modell

The kidneys are susceptible to harm from exposure to chemicals they filter from the bloodstream. This can lead to organ injury associated with a rapid ...

A Graphical User Interface for Software-assisted Tracking of Protein Concentration in Dynamic Cellular Protrusions

Filopodia are dynamic, finger-like cellular protrusions associated with migration and cell-cell communication. In order to better understand the complex signaling mechanisms underlying filopodial initiation, elongation and subsequent stabilization or retraction, it is crucial to determine the spatio-temporal protein activity in these dynamic structures. To analyze protein function in filopodia, we recently developed a semi-automated tracking algorithm that adapts to filopodial shape-changes, thus allowing parallel analysis of protrusion dynamics and relative protein concentration along the whole filopodial length. Here, we present a detailed step-by-step protocol for optimized cell handling, image acquisition and software analysis. We further provide instructions for the use of optional features during image analysis and data representation, as well as troubleshooting guidelines for all critical steps along the way. Finally, we also include a comparison of the described image analysis software with other programs available for filopodia quantification. Together, the presented protocol provides a framework for accurate analysis of protein dynamics in filopodial protrusions using image analysis software.

We present a software solution for semi-automated tracking of relative protein concentration along the length of dynamic cellular protrusions.

Eine grafische Benutzeroberfläche für die softwaregestützte Verfolgung der Proteinkonzentration in dynamischen zellulären Vorsprüngen

Filopodia are dynamic, finger-like cellular protrusions associated with migration and cell-cell communication. In order to better understand the complex ...

Trans-inner Cell Mass Injection of Embryonic Stem Cells Leads to Higher Chimerism Rates

In an effort to increase efficiency in the creation of genetically modified mice via ES Cell methodologies, we present an adaptation to the current blastocyst injection protocol. Here we report that a simple rotation of the embryo, and injection through Trans-Inner cell mass (TICM) increased the percentage of chimeric mice from 31% to 50%, with no additional equipment or further specialized training. 26 different inbred clones, and 35 total clones were injected over a period of 9 months. There was no significant difference in either pregnancy rate or recovery rate of embryos between traditional injection techniques and TICM. Therefore, without any major alteration in the injection process and a simple positioning of the blastocyst and injecting through the ICM, releasing the ES cells into the blastocoel cavity can potentially improve the quantity of chimeric production and subsequent germline transmission.

Here we present a protocol to increase chimera production without the use of new equipment. A simple orientation change of the embryo for injection can increase the number of embryos produced, and potentially reduce the timeline to germline transmission.

Trans-innere Zelle Masse Injektion von embryonalen Stammzellen führt zu höheren Chimerism Raten

In an effort to increase efficiency in the creation of genetically modified mice via ES Cell methodologies, we present an adaptation to the current ...

Isolation, Proliferation and Differentiation of Rhesus Macaque Adipose-Derived Stem Cells

Adipose tissue provides a rich and accessible source of multipotent stem cells, which are able to self-renew. These adipose-derived stem cells (ADSCs) provide a consistent ex vivo cellular system that are functionally like that of in vivo adipocytes. Use of ADSCs in biomedical research allows for cellular investigation of adipose tissue metabolic regulation and function. ADSC differentiation is necessary for adequate adipocyte expansion, and suboptimal differentiation is a major mechanism of adipose dysfunction. Understanding changes in ADSC differentiation is crucial to understanding the development of metabolic dysfunction and disease. The protocols described in this manuscript, when followed, will yield mature adipocytes that can be used for several in vitro functional tests to assess ADSC metabolic function, including but not limited to assays measuring glucose uptake, lipolysis, lipogenesis, and secretion. Rhesus macaques (Macaca mulatta) are physiologically, anatomically, and evolutionarily similar to humans and as such, their tissues and cells have been used extensively in biomedical research and for development of treatments. Here, we describe ADSC isolation using fresh subcutaneous and omental adipose tissue obtained from 4&#8211;9-year old rhesus macaques. Adipose tissue samples are enzymatically digested in collagenase followed by filtration and centrifugation to isolate ADSCs from the stromal vascular fraction. Isolated ADSCs are proliferated in stromal media followed by approximately 14&#8211;21 days of differentiation using a cocktail of 0.5 &#956;g/mL dexamethasone, 0.5 mM isobutyl methylxanthine, and 50 &#956;M indomethacin in stromal media. Mature adipocytes are observed at approximately 14 days of differentiation. In this manuscript, we describe protocols for ADSC isolation, proliferation, and differentiation in vitro. Although, we have focused on ADSCs from rhesus macaque adipose tissue, these protocols can be utilized for adipose tissue obtained from other animals with minimal adjustments.

In this article, we describe isolation of rhesus macaque derived adipose-derived stem cells (ADSCs) using an enzymatic tissue digestion protocol. Next, we describe ADSC proliferation which includes cell detachment, counting and plating. Lastly, ADSC differentiation is described using specific adipogenic inducing agents. Additionally, we describe staining techniques to confirm differentiation.

Isolierung, Proliferation und Differenzierung von Rhesusaffen-Fettstammzellen

Adipose tissue provides a rich and accessible source of multipotent stem cells, which are able to self-renew. These adipose-derived stem cells (ADSCs) ...