General Wir empfehlen dem Auftauen nicht mehr als eine Probe zu einem bestimmten Zeitpunkt auf eine einfache Handhabung zu gewährleisten. Der Hundeführer sollte darauf achten, dass Kulturen bei Raumtemperatur und niedrigen CO2-Urlaub für längere Zeit. Alle Zentrifugation von lebenden Zellen ist bei 500-600 xg für 5 min bei Raumtemperatur. MEFs (embryonalen Feeder-Zellen) <ol><li> Pre-warm MEF Medien bis 37 ° C. Entfernen Sie MEF Fläschchen von -80 ° C und sofort tauchen die untere Hälfte der Röhre in einem 37 ° C Wasserbad. Es sollte ca. 30-45 Sekunden dauern, bevor die Zellen 80% aufgetaut (kleine gefrorene Teil links). </li><li> Bringt schnell das Rohr auf die Laminarströmungshaube, abspritzen mit 70% Alkohol und Transfer Zellen vorgewärmte Medien. </li><li> Saugen Sie die Gelatine-Lösung von Platten hergestellt früher. </li><li> Aliquot von 2 ml MEF-Lösung in einem tropfenweise Weise in jeder der sechs Brunnen. Achten Sie darauf, die MEFs gleichmäßig zu verteilen über den Brunnen. Datum der MEF Platte und in einem 37 ° C Inkubator über Nacht zu ermöglichen MEFs auf Platte befestigen. </li><li> Nach 6 Stunden MEFs wird an der Platte befestigt werden. Es ist am besten zu nutzen MEF Platten 24-48 Stunden nach dem Ausplattieren. NICHT in der MEF Platte, die über 4 Tage alt ist. </li><li> Pre-warmen Farbtönen Medien und 0,05% Trypsin / EDTA auf 37 ° C Unter der Haube prelabel ein steriles 50 ml konischen Rohr. </li><li> Vorsichtig absaugen Die Farbtöne Medien aus der Kultur, die geteilt werden. Vorsichtig waschen die Vertiefungen mit 2 ml 1X Phosphat-gepufferter Lösung (PBS) pro Vertiefung. Saugen Sie das PBS. Add 0,75 ml 0,05% Trypsin / EDTA zum Brunnen. </li><li> Ersetzen Deckel, und beobachten Sie die Zellen unter 4x Vergrößerung. Die MEFs umliegenden Die Farbtöne Kolonien beginnen sich zurückzuziehen. Wenn die MEFs ausreichend sind gerundet und die Grenzen der Farbtöne Kolonien sind rau, Rückkehr der Platte an der Kapuze. Dieser Prozess dauert ca. 5 Minuten, absolut nicht länger als 10 Minuten oder Ihre Zellen nicht wieder wachsen. </li><li> Gently Pipette auf und ab, das Waschen der Grund des Brunnens, bis die MEF Monoschicht völlig losgelöst hat (Monolayer ist klebrig und kann in einem Stück bleiben). </li><li> Übertragen Sie die Zellsuspension auf eine 50 ml konische Röhrchen mit zusätzlichen FARBEN Medien. Drehen Sie das Rohr von Zellen 500 xg für 5 Minuten, Absaugen der Medien, darauf achten, nicht das Zellpellet zu stören. </li><li> Um Platte auf eine neue Platte von MEFs, fügen Sie den entsprechend bestimmten Volumen der Zellen, um zusätzliche FARBEN Medien und Pipette die Lösung 5-7 mal mit einem automatisierten Pipette. </li><li> Entfernen Sie die MEF Druckmedien aus einem neuen Platte von MEFs. </li><li> Aliquot der Farbtöne Lösung tropfenweise in jede Vertiefung, so dass Sie die Tropfen gleichmäßig über die gut zu verteilen. Ohne Schütteln der Platte vorsichtig wieder die Zellen zu einer 37 ° C Inkubator über Nacht zu lassen FARBEN Kolonien Samen. </li><li> FARBEN Zellen kommen aus einem geteilten sollte sich ähnlich wie diejenigen, die aus einem Tauwetter. </li></ol>

<ol>
	<li>Edmond, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nosocomial+bloodstream+infections+in+United+States+hospitals:+a+three-year+analysis.">Nosocomial bloodstream infections in United States hospitals: a three-year analysis.</a> Clin. Infect. Dis. 29, 239-244 (1999).</li><li>Ramage, G., Bachmann, S., Patterson, T. F., Wickes, B. L., Lopez-Ribot, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+of+multidrug+efflux+pumps+in+relation+to+fluconazole+resistance+in+Candida+albicans+biofilms.">Investigation of multidrug efflux pumps in relation to fluconazole resistance in Candida albicans biofilms.</a> J. Antimicrob. Chemother. 49, 973-980 (2002).</li><li>Srinivasan, A., Uppuluri, P., Lopez-Ribot, J., Ramasubramanian, 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=Development+of+a+High-Throughput+Candida+albicans+Biofilm+Chip.">Development of a High-Throughput Candida albicans Biofilm Chip.</a> PLoS ONE. 6, 19036-19036 (2011).</li><li>Ramage, G., Vandewalle, K., Wickes, B. L., Lopez-Ribot, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characteristics+of+biofilm+formation+by+Candida+albicans.">Characteristics of biofilm formation by Candida albicans.</a> Rev. Iberoam. Micol. 18, 163-170 (2001).</li><li>Pierce, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+and+reproducible+96-well+plate-based+method+for+the+formation+of+fungal+biofilms+and+its+application+to+antifungal+susceptibility+testing.">A simple and reproducible 96-well plate-based method for the formation of fungal biofilms and its application to antifungal susceptibility testing.</a> Nat. Protoc. 3, 1494-1500 (2008).</li><li>Lee, M. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+cellular+microarray+for+high-throughput+toxicology+assays.">Three-dimensional cellular microarray for high-throughput toxicology assays.</a> Proc. Natl. Acad. Sci. U.S.A. 105, 59-63 (2008).</li><li>Meyerhofer, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characteristics+of+resist+films+produced+by+spinning.">Characteristics of resist films produced by spinning.</a> Journal of Applied Physics. 49, (1978).</li><li>Ramage, G., Vande Walle, K., Wickes, B. L., Lopez-Ribot, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Standardized+method+for+in+vitro+antifungal+susceptibility+testing+of+Candida+albicans+biofilms.">Standardized method for in vitro antifungal susceptibility testing of Candida albicans biofilms.</a> Antimicrob. Agents Chemother. 45, 2475-2479 (2001).</li><li>Chandra, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biofilm+formation+by+the+fungal+pathogen+Candida+albicans:+Development,+architecture,+and+drug+resistance.">Biofilm formation by the fungal pathogen Candida albicans: Development, architecture, and drug resistance.</a> Journal of Bacteriology. 183, 5385-5394 (2001).</li><li>Jabra-Rizk, M. A., Falkler, W. A., Meiller, T. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fungal+biofilms+and+drug+resistance.">Fungal biofilms and drug resistance.</a> Emerg. Infect. Dis. 10, 14-19 (2004).</li><li>Tobudic, S., Lassnigg, A., Kratzer, C., Graninger, W., Presterl, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antifungal+activity+of+amphotericin+B,+caspofungin+and+posaconazole+on+Candida+albicans+biofilms+in+intermediate+and+mature+development+phases.">Antifungal activity of amphotericin B, caspofungin and posaconazole on Candida albicans biofilms in intermediate and mature development phases.</a> Mycoses. 53, 208-214 (2010).</li></ol>

In diesem Video demonstriert, wie wir routinemäßig Durchgang FARBEN humanen embryonalen Stammzelllinien in unserem Labor. Effiziente und regelmäßige Aufteilung und Passagieren ist essentiell für die Aufrechterhaltung einer gesunden menschlichen embryonalen Stammzell-Linie. Trypsin-vermittelten Passage ist ein wesentlicher Vorteil von Farbtönen Zelllinien, ist es jedoch wichtig, nicht über trypsinize Kulturen oder zu einem großen Anteil der einzelnen Zellen während des Wiedereintritts Flechten haben.

FARBEN Medien 651,5 ml KO-DMEM 500 ml PenStrep 6,5 ml GlutaMAXTM 6,5 ml NEAA 6,5 ml 2-Mercaptoethanol 0.5ul KO Serum Replacement 65 ml Plasmanate 65 ml bFGF2 (10 ng / mL Finale) 0,65 ml

passaging hues human embryonic stem cell-lines with trypsin.

In diesem Video zeigen wir, wie unser Labor routinemäßig Passagen FARBEN humanen embryonalen Stammzell-Linien mit Trypsin. Menschliche embryonale Stammzellen sind Artefakte der Zellkultur, und neigen dazu, karyotypischen Anomalien mit hoher Populationsverdopplungen erwerben. Proper Passagieren ist essentiell für die Aufrechterhaltung einer gesunden, undifferenziert, karyotypisch normalen FARBEN menschlichen embryonalen Stammzellen Kultur. Erstens, eine expandierende Kultur in PBS gewaschen, um restliches Medium und Zelltrümmer zu entfernen, dann Zellen werden mit einem minimalen Volumen von warmen 0,05% Trypsin-EDTA überlagert. Trypsin auf die Zellen für bis zu fünf Minuten nach links, dann Zellen werden vorsichtig mit einer 2-ml-serologischen Pipette verdrängt. Die Zellsuspension gesammelt und mit einem großen Volumen von Farbtönen Medien vermischt, dann Zellen werden durch sanfte Zentrifugation gesammelt. Das inaktivierte Trypsin Medien Gemisch entfernt und die Zellen in vorgewärmten FARBEN Medien resuspendiert. Eine entsprechende Teilungsverhältnis wird berechnet (in der Regel von 1.10 bis 01.20 Uhr), und die Zellen auf eine 1-2 Tage alten Platte mit einer Monoschicht von bestrahlten embryonalen Maus-Fibroblasten-Feeder-Zellen re-vernickelt. Die neu ausgesät FARBEN Kultur Platte links ungestört ist für 48 Uhr, dann werden die Medien wird jeden Tag danach. Es ist wichtig, nicht zu trpsinize auf eine einzige Zellsuspension, wie dies erhöht die Gefahr der Einschleppung von karyotypischen Anomalien.

Watch this Scientific Journal Video about Passaging HuES Human Embryonic Stem Cell-lines with Trypsin. at JoVE.com

Passaging HuES Human Embryonic Stem Cell-lines with Trypsin.

In diesem Video zeigen wir, wie unser Labor routinemäßig Passagen FARBEN humanen embryonalen Stammzell-Linien mit Trypsin.

Passagierung FARBEN humanen embryonalen Stammzellen-Linien mit Trypsin

In this video we demonstrate how our lab routinely passages HuES human embryonic stem cell lines with trypsin.  Human embryonic stem cells are artifacts ...

This is, where did you run The techniques? Oh, where did I teach you? Belcher.Yeah.The first time I did teach you Bel, I spent the summer at my T.Yeah.And that was like, we did like cartilage stuff there. And so I did like social culture there. And then at Hopkins my senior year I worked with different, so I, for like the engineering thing, it was much more about trying, we engineer three dimensional that.

passaging-hues-human-embryonic-stem-cell-lines-with-trypsin

Research

JoVE Journal

Biology

252.0K Aufrufe.  Harvard. This is, where did you run The techniques? Oh, where did I teach you? Belcher.Yeah.The first time I did teach you Bel, I spent the summer at my T.Yeah.And that was like, we did like cartilage stuff there. And so I did like social culture there. And then at Hopkins my senior year I worked with different, so I, for like the engineering thing, it was much more about trying, we engineer three dimensional that.

Serie: Passaging HuES Human Embryonic Stem Cell-lines with Trypsin.

Propagation of Human Embryonic Stem (ES) Cells

Propagation of Human Embryonic Stem ES Cells

Yeah, so I'm Lauren Deon. I'm in charge of the Human Amgen stem cell co facility at MGH. Yeah, so I'm Lauren, I'm in charge of the Human AM stem cell co facility at MGH.So I've been working with human Amgen stem cells for years now since I was a postdoc in George De Lab before, from four, four years. And so right now we have two cell lines, H one and H nine, which are both from Y cell. And so the way we are expanding or maintaining these cells in culture is by, at least the way we are splitting these cells is by using collagenous.So what I usually do is for the first few passage after throwing the cells, I use a technical, the picking colonies. So in this case, I can check under the microscope which colonies are good and differentiate and nice shape, and I will collect only these colonies and I will cut them in few pieces and put them back in, in a fresh flat. And the, the colonies that look kind of differentiate it are just left them alone.The other way to pass the cells is by using trypsin. So I don't use this technique here. I think collagenase is a little bit safer because human being stem cells don't like to be individualized or they don't like to be alone.So if you do trypsin, if you use trypsin for a little bit too long, if you use it for like three to four minutes, which is the way we use strips in for other type of cells, human stem cells will be individualized and most of them will die or just differentiate or will not attach to the myth. So the idea is you have to keep the cells as clumps. You don't want them to be alone in the in, in the flask.So using collagenase, the advantage is to keep cells as plants. Using chipsy, you just select for cells that will survive this very, very harsh process of g opsonization. So these cells are usually very highly proliferative.So you get, you can adapt your cells to this tripsin process. The problem is that you have cells that they behave differently, they go much faster. And one risk is that you can get some commercial abnormality to, to this, to this very high division process.So you say that ization can cause selection of cells in culture for most proliferative cells.Right. More ative and probably also higher survival rates than other cells. So after proliferation, basically culture after proliferation in tripsin, after several passages become a different culture, these different properties.So it's, it's hard to figure out if they are exactly identical. If you do the test, the usual test, let's say you check markers, regular markers of end differentiated cells like OC four, nano one 60 SC four C, C3, all this molecule might still be expressed. If you do TER formation, this cells might still differentiate and be formed like al like normal cells.If you look at the karyotype, you might have some abnormality, but you might still have a normal karyotype. The, the, the selective advantage might be due to just a mutation that you cannot see by doing a karyotype. So the fact that they grow much faster is by itself I think a little bit worser.And if we want to use these cells for transplantation at some point, I would definitely not use this type of cells.Okay. So would you like to tell me what are the main technical problems with using this technique for, for passages of cells? So using S, yes.It's just a little bit longer and also it's, since the cells are not going as fast, it's just much longer to get a high number of cells to do some experiment. So it's just less convenient I would say. Would you like to tell me about few words about the goals of your experiment?How do you use CS cells? Okay, so my main project here is to get endothelial cells from human AB stem cells. And the idea is to be able to make blood.And we are working a lot with tissue bioengineering labs and one of their goal is to make tissue in vitro. But one of the limitation to this is the lack of blood vessels going through this tissues. So if we can bring endothelial cells or put endothelial cells in this tissue, we would have better growth of this tissue.So the idea few sources of cells are known for endothelial cells like cold blood or pressure blood, but it would be interesting to have another source of cells like human years. And the advantage is since human years can be expanded and most infinitely, you could modify these cells, make some inducible system and be able to use it. Then in your final product, your material cells, in this case.

Vermehrung von humanen embryonalen Stammzellen (ES-Zellen)

Forschung

Biologie

Passaging Human Neural Stem Cells

The ability to manipulate human neural stem/precursor cells (hNSPCs) in vitro provides a means to investigate their utility as cell transplants for therapeutic purposes as well as to explore many fundamental processes of human neural development and pathology.  This protocol presents a simple method of culturing and passaging hNSPCs in hopes of standardizing this technique and increasing reproducibility of human stem cell research.  The hNSPCs we use were isolated from cadaveric postnatal brain cortices by the National Human Neural Stem Cell Resource and grown as adherent cultures on flasks coated with fibronectin (Palmer et al., 2001; Schwartz et al., 2003).  We culture our hNSPCs in a DMEM:F12 serum-free media supplemented with EGF, FGF, and PDGF and passage them 1:2 approximately every seven days.  Using these conditions, the majority of the cells in the culture maintain a bipolar morphology and express markers of undifferentiated neural stem cells (such as nestin and sox2).

The ability to manipulate human neural stem/precursor cells (hNSPCs) in vitro allows to investigate their utility as cell transplants for therapeutic purposes and to explore human neural development. This protocol presents a method of culturing and passaging hNSPCs in hopes of increasing reproducibility of human stem cell research.

Passagierung humaner neuraler Stammzellen

The ability to manipulate human neural stem/precursor cells (hNSPCs) in vitro provides a means to investigate their utility as cell transplants for ...

Derivation of Human Embryonic Stem Cells by Immunosurgery

The ability of human embryonic stem cells to self-renew and differentiate into all cell types of 
the body suggests that they hold great promise for both medical applications and as a research 
tool for addressing fundamental questions in development and disease. Here, we provide a 
concise, step-by-step protocol for the derivation of human embryonic stem cells from embryos 
by immunosurgical isolation of the inner cell mass. 


The ability of human embryonic stem cells to self-renew and differentiate into all cell types of 
the body suggests that they hold great promise for both medical applications and as a research 
tool for addressing fundamental questions in development and disease. Here, we provide a 
concise, step-by-step protocol for the derivation of human embryonic stem cells from embryos 
by immunosurgical isolation of the inner cell mass.

Gewinnung menschlicher embryonaler Stammzellen durch Immunosurgery

The ability of human embryonic stem cells to self-renew and differentiate into all cell types of 
the body suggests that they hold great promise for both ...

Probing for Mitochondrial Complex Activity in Human Embryonic Stem Cells

Mitochondria are cytoplasmic organelles that have a primary role in cellular metabolism and homeostasis, regulation of the cell signaling network, and programmed cell death. Mitochondria produce ATP, regulate the cytoplasmic redox state and Ca2+ balance, catabolize fatty acids, synthesize heme, nucleotides, steroid hormones, amino acids, and help assemble iron-sulfur clusters in proteins. Mitochondria also have an essential role in heat production. Mutations of the mitochondrial genome cause several types of human disorder. The accumulation of mtDNA mutations correlates with aging and is suspected to have an important role in the development of cancer. Due to their vitally important role in all cell types, the function of mitochondria must also be critical for stem cells. Key advances have been made in our understanding of stem cell viability, proliferation, and differentiation capacity. But the functional activity of stem cells, in particular their energy status, was not yet been studied in detail. Almost nothing is known about the mitochondrial properties of human embryonic stem cells (hESCs) and their differentiated precursor progeny. One way to understand and evaluate the role of mitochondria in hESC function and developmental potential is to directly measure the activity of mitochondrial respiratory complexes. Here, we describe high resolution clear native gel electrophoresis and subsequent in gel activity visualization as a method for analyzing the five respiratory chain complexes of hESCs.

In this video, we will show you how the mitochondrial respiratory chain complexes of human embryonic stem cells can be analyzed using in gel activity assays.

Probing für Mitochondriale komplexe Aktivität in humanen embryonalen Stammzellen

Mitochondria are cytoplasmic organelles that have a primary role in cellular metabolism and homeostasis, regulation of the cell signaling network, and ...

Chromatin Immunoprecipitation from Human Embryonic Stem Cells

The functional and structural complexity of the myriad of cells in metazoan organisms arises from a small number of stem cells. Stem cells are characterized by two fundamental properties: self-renewal and multipotency that allows a stem cell to differentiate into virtually any cell type 1. The progression stem cell to differentiated cell is characterized by loss of multipotency, structural and morphological changes and the hierarchic activity of transcription factors and signaling molecules, whose activities establish and maintain cell-type specific gene expression patterns. At the molecular level, cell differentiation involves dynamic changes of the structure and composition of chromatin and the detection of those dynamic changes can provide valuable insights into the functional features of stem cells and the cell differentiation process 2,3. Chromatin is a highly compacted DNA-protein complex that forms when cells package chromosomal DNA with proteins, mainly histones 4. Stemcellness and cell differentiation has been correlated with the presence of specific arrays of regulatory proteins such as epigenetic factors, histone variants, and transcription factors 2,3,5.
 Chromatin immunoprecipitation (ChIP) provides a valuable method to monitor the presence of RNA, proteins, and protein modifications in chromatin 6,7. The comparison of chromatin from different cell types can elucidate dynamic changes in protein-chromatin associations that occur during cell differentiation.
Chromatin immunoprecipitation involves the purification of in vivo cross-linked chromatin. The isolated chromatin is reduced to smaller fragments by enzymatic digestion or mechanical force. Chromatin fragments are precipitated using specific antibodies to target proteins or protein and DNA modifications. The precipitated DNA or RNA is purified and used as a template for PCR or DNA microarray based assays. Prerequisites for a successful ChIP are high quality antibodies to the desired antigen and the availability of chromatin from control cells that do not express the target molecule. ChIP can correlate the presence of proteins, protein and RNA modifications, and RNA with specific target DNA, and depending on the choice of outread tool, detects the association of target molecules at specific target genes or in the context of an entire genome. The comparison of the distribution of proteins in the chromatin of differentiating cells can elucidate the dynamic changes of chromatin composition that coincide with the progression of cells along a cell lineage.

The differentiation of ESC coincides with cell-type specific changes in the structure and composition of chromatin. The detection of those changes provides valuable insights into the mechanisms that define stemcellness and cell differentiation. Chromatin immunoprecipitation (ChIP) represents a valuable method to dissect the molecular mechanisms underlying stem cell differentiation.

Chromatin Immunopräzipitation von humanen embryonalen Stammzellen

The functional and structural complexity of the myriad of cells in metazoan organisms arises from a small number of stem cells. Stem cells are ...

Culture and Maintenance of Human Embryonic Stem Cells  

Human embryonic stem (hES) cells must be monitored and cared for in order to maintain healthy, undifferentiated cultures. At minimum, the cultures must be  fed  every day by performing a complete medium change to replenish lost nutrients and to keep the cultures free of unwanted differentiation factors. Although a small amount of differentiation is normal and expected in stem cell cultures, the culture should be routinely cleaned up by manually removing, or "picking" differentiated areas. Identifying and removing excess differentiation from hES cell cultures are essential techniques in the maintenance of a healthy population of cells.

Culture and Maintenance of Human Embryonic Stem Cells

This protocol demonstrates how to maintain healthy, undifferentiated human embryonic stem (ES) cells.

Kultur und Wartung von humanen embryonalen Stammzellen

Human embryonic stem (hES) cells must be monitored and cared for in order to maintain healthy, undifferentiated cultures. At minimum, the cultures must be ...

Chromosomal Spread Preparation of Human Embryonic Stem Cells for Karyotyping

Although human embryonic stem cells (hESC) have been shown to present a stable diploid karyotype 1, many studies have reported that depending on culture conditions they become prone to acquire chromosomal anomalies such as addition of whole or parts of chromosomes. Indeed, during long-term culture, karyotypic alterations are observed when enzymatic or chemical dissociation are used 2,3,4, while manual dissection of colonies for passaging retains a stable karyotype 5. Besides, changes in the environment such as the removal of feeder cells also seem to compromise the genetic integrity of hESC 3,6. Once chromosomal alterations could affect cellular physiology, the characterization of the genetic integrity of hESC in vitro is crucial considering hESC as an essential tool in embryogenesis studies and drug testing. Furthermore, for future therapeutic purposes chromosomal changes are a real concern as it is frequently associated to carcinogenesis.
Here we show a simple and useful method to obtain high quality chromosome spreads for subsequent analysis of chromosome set by G-banding, FISH, SKY or CGH techniques 7,8. We recommend checking the chromosomal status routinely with intervals of 5 passages in order to monitor the appearance of translocations and aneuploidies
Priscila Britto and Rafaela Sartore contributed equally to the paper.

Karyotyping is a simple and useful technique widely used for detecting genetic alterations. Here we describe a step by step protocol for chromosome spread preparation of human embryonic stem cells for monitoring the chromosomal status of these cells maintained in culture.

Chromosomale Spread-Vorbereitung von humanen embryonalen Stammzellen für die Karyotypisierung

Although human embryonic stem cells (hESC) have been shown to present a stable diploid karyotype 1, many studies have reported that depending on culture ...

Freezing and Thawing Human Embryonic Stem Cells

Since James Thomson et al developed a technique in 1998 to isolate and grow hES in culture, freezing cells for later use and thawing and expanding cells from a frozen stock have become important procedures performed in routine hES cell culture. Since hES cells are very sensitive to the stresses of freezing and thawing, special care must taken. Here we demonstrate the proper technique for rapidly thawing hES cells from liquid nitrogen stocks, plating them on mouse embryonic feeder cells, and slowly freezing them for long-term storage.

Since James Thomson et al developed a technique in 1998 to isolate and grow hES in culture, freezing cells for later use and thawing and expanding cells from a frozen stock have become important procedures performed in routine hES cell culture. Since hES cells are very sensitive to the stresses of freezing and thawing, special care must taken. Here we demonstrate the proper technique for rapidly thawing hES cells from liquid nitrogen stocks, plating them on mouse embryonic feeder cells, and slowly freezing them for long-term storage.

Einfrieren und Auftauen humanen embryonalen Stammzellen

Since James Thomson et al developed a technique in 1998 to isolate and grow hES in culture, freezing cells for later use and thawing and expanding cells ...

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 ...

Fate Mapping of Human Embryonic Stem Cells by Teratoma Formation

Human embryonic stem cells (hESCs) have an unlimited capacity for self-renewal, and the ability to differentiate into cells derived from all three embryonic germ layers (1). Directed differentiation of hESCs into specific cell types has generated much interest in the field of regenerative medicine (e.g., (2-5)), and methods for determining the in vivo fate of selected or manipulated hESCs are essential to this endeavor. We have adapted a highly efficient teratoma formation assay for this purpose. A small number of specifically selected hESCs is mixed with undifferentiated wild type hESCs and Phaseolus vulgaris lectin to form a cell pellet. This is grafted beneath the kidney capsule in an immunodeficient mouse. As few as 2.5 x 105 hESCs are needed to form a 16 cm3 teratoma within 8-12 weeks. The fate of the originally selected hESCs can then be determined by immunohistochemistry. This method provides a valuable tool for characterizing tissue-specific reagents for cell-based therapy.

Directed differentiation of hESCs into specific cells has generated much interest in regenerative medicine. We provide a concise, step-by-step protocol for determining the in vivo fate of selected hESCs that provides a valuable tool for characterizing tissue-specific reagents for cell-based therapy.