A.E.C. is a fellow of the Jane Coffin Childs Memorial Fund for Medical Research and Merck Research Laboratories. We thank D. Egli and C. Cowan for experimental advice and discussion.

Frozen human embryos used for human embryonic stem (hES) cell derivation were donated for research following proper informed consent under research protocols that were reviewed and approved by both the committee on the use of human subjects and the embryonic stem cell research oversight committee at Harvard University.
Written protocol below is based on published parameters reported by Cowan et al. 2004, with slight modifications.
Embryo Culture
Thaw human embryos using Quinn's Advantage Thaw Kit and culture in drops of Global medium supplemented with 15% Plasmanate until development to the expanded blastocyst stage.
Immunosurgery-based isolation of the inner cell mass
Preparation:
<ol>
<li>Prepare plates for removal of the zona pellucida and immunosurgery (see below) by setting up drops of each solution in 10cm plates. Overlay with mineral oil to prevent evaporation. Prepare a single row per embryo intended for derivation. 
<ul>
<li>EmbryoMax Acidic Tyrodes, use as is.</li>
<li>hES cell derivation media: 75% KO-DMEM, 10% KO-Serum Replacement, 10% Plasmanate, 2.5% ES cell-tested fetal bovine serum (FBS), 2mM Glutamax-I, 1% non-essential amino acids, 50 units/ml penicillin, 50&micro;g/ml streptomycin, 0.055mM b-mercaptoethanol, 5ng/ml bFGF.</li>
<li>Rabbit anti-human red blood cell primary antibody, reconstituted according to manufacturer's suggestion, diluted at 1:10 with hES cell derivation media.</li>
<li>Guinea-pig complement serum, reconstituted according to manufacturer's suggestion, diluted at 1:10 with hES cell derivation media. <img src="/files/ftp_upload/old/574_2008_9_18_6/574_Figure-01.png" alt="574_Figure-01" width="600" height="166" /> </li>
</ul>
</li>
<li>Equilibrate all plates to 37&deg;C in tissue culture incubator before use.</li>
<li>Pull 50&micro;l-100&micro;l capillary pipettes (VWR) for use in transferring embryos. Cut ends with diamond pen and use with mouth pipette tubing equipped with a 0.2&micro;m filter.</li>
</ol>
Immunosurgery Procedure:
Notes:
<ul>
<li>In this procedure, cells of the trophectoderm are destroyed by brief exposure to antibodies directed against human cells in tandem with complement activity. Therefore, protocol works best with high-quality embryos with an intact trophectoderm, as only the structural integrity of the blastocyst prevents the ICM from also being susceptible to the immunological reaction.</li>
<li>All procedures performed using a dissection scope equipped with heated stage.</li>
</ul>
Steps:
<ol>
<li>Rinse mouth pipette to be used for embryo transfer with FBS to prevent embryos from sticking.</li>
<li>Transfer blastocyst from culture dish to hES holding drop of AT dish.</li>
<li>Begin procedure by transferring blastocyst from hES drop through series of AT drops. In third drop, watch for dissolution of zona pellucida (usually 5-30 seconds). Be careful not to over-treat or embryo integrity may be compromised. <img src="/files/ftp_upload/old/574_2008_7_21_2/574_Figure-02.png" alt="574_Figure-02" width="551" height="273" /> </li>
<li>Transfer blastocyst through series of hES cell derivation media drops to rinse off AT. Preloading pipette with media is recommended to immediately neutralize AT reaction. Blastocysts can be held here until all have been AT-processed.</li>
<li>Transfer blastocyst through series of primary antibody drops, leaving in third drop for 30 minutes of incubation at 37&deg;C in a tissue culture incubator.</li>
<li>Transfer blastocyst through series of hES cell derivation media drops to rinse off primary.</li>
<li>Transfer blastocyst through series of complement drops, leaving in third drop to watch for lysis of trophectoderm cells. Observe blastocyst for the first 30 seconds on stage for "bubbling" of trophectoderm cells as they lyse. If lysis is observed within this time frame, keep dish on microscope stage to monitor the reaction until completion. If no bubbling is observed during the first 30 seconds, return to incubator, checking every 5 minutes until most of the trophectoderm has lysed. This can take 5-15 minutes. Monitor reaction closely to minimize reaction time and potential damage to the inner cell mass. <img src="/files/ftp_upload/old/574_2008_7_21_3/574_Figure-03.png" alt="574_Figure-03" width="571" height="273" /> </li>
<li>Transfer blastocyst through series of hES cell derivation media drops to wash off complement activity.</li>
<li>Using glass pipette with a diameter that is slightly smaller than the blastocyst (pulled from 10&micro;l VWR capillary tubes), draw the blastocyst up and down to strip away most of the lysed trophectoderm. <img src="/files/ftp_upload/old/574_2008_7_21_4/574_Figure-04.png" alt="574_Figure-0" width="577" height="270" /> </li>
<li>Plate ICM isolate onto feeder cells of mitotically inactivated mouse embryo fibroblasts (MEFs). MEFs should be prepared the day before derivation and switched to hES cell derivation media day of. 4-well NUNC dishes work well for initial steps of derivation.</li>
<li>Do not disturb plate for first 1-2 days. Thereafter, check daily for outgrowth of embryonic stem cell colonies (usually apparent within 1-2 weeks). Media should be changed in half volumes every other day beginning on day 3.</li>
</ol>
ES cell outgrowth and passaging
When the hES cell outgrowth has reached approximately 0.5mm or more, it is ready for expansion by mechanical picking.
<ol>
<li>Mechanically disperse half of the outgrowth and transfer to new plates containing fresh feeders. Embryonic stem cell clumps should be approximately 30-50 cells each. Leave other half of outgrowth as a back-up for the first passage (p1). The outgrowth (p0) can be picked from several times as it continues to expand. <img src="/files/ftp_upload/old/574_2008_7_21_5/574_Figure-05.png" alt="574_Figure" width="639" height="219" /> </li>
<li>Secondary colonies can be similarly dispersed and expanded across bigger culture dishes until passages 3-5, at which time the new cell lines can be adapted to enzymatic passaging with trypsin. The serum content of the culture media should also be gradually reduced to 1% and 0% during these initial passages to minimize ES cell differentiation.</li>
<li>All established embryonic stem cell lines should be banked by freezing down a portion of early passages for future expansions.</li>
<li>In addition, each cell line should be characterized by karyotype analysis and validated by pluripotency and differentiation studies in vitro and in vivo. </li>
</ol>

<ol>
	<li>Cowan, C. A., Klimanskaya, I., McMahon, J., Atienza, J., Whitmyer, J., Zucker, J. P., Wang, S. P., Morton, C. C., McMahon, A. P., Powers, D., Melton, D. A. <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+embryonic+stem-cell+lines+from+human+blastocysts.">Derivation of embryonic stem-cell lines from human blastocysts.</a> N ENGL J MED. 350 (13), 1353-1356 (2004).</li></ol>

The authors have nothing to disclose.

The protocol presented here provides researchers with a concise, easy-to-follow outline of how to derive human embryonic stem cell lines by immunosurgical isolation of the inner cell mass.

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Quinn's Advantage Thaw Kit </td>
<td>&nbsp;</td>
<td>Sage</td>
<td>ART-8016</td>
<td>&nbsp;</td>
<tr>
<td>Global medium</td>
<td>&nbsp;</td>
<td>Life Global</td>
<td>GMGB-050</td>
<td>&nbsp;</td>
<tr>
<td>Plasmanate</td>
<td>&nbsp;</td>
<td>Talecris</td>
<td>61325</td>
<td>&nbsp;</td>
<tr>
<td>EmbryoMax Acidic Tyrodes</td>
<td>&nbsp;</td>
<td>Chemicon/Millipore</td>
<td>MR-004-D</td>
<td>&nbsp;</td>
<tr>
<td>KO-DMEM</td>
<td>&nbsp;</td>
<td>Invitrogen/Gibco</td>
<td>10829-018</td>
<td>&nbsp;</td>
<tr>
<td>KO-Serum Replacement</td>
<td>&nbsp;</td>
<td>Invitrogen/Gibco</td>
<td>10828-028</td>
<td>&nbsp;</td>
<tr>
<td>ES cell-tested fetal bovine serum, Defined</td>
<td>&nbsp;</td>
<td>Hyclone</td>
<td>SH30070.03</td>
<td>&nbsp;</td>
<tr>
<td>Glutamax-I</td>
<td>&nbsp;</td>
<td>Invitrogen/Gibco</td>
<td>35050-079</td>
<td>&nbsp;</td>
<tr>
<td>Non-essential amino acids</td>
<td>&nbsp;</td>
<td>Invitrogen/Gibco</td>
<td>11140-076</td>
<td>&nbsp;</td>
<tr>
<td>Penicillin/Streptomycin</td>
<td>&nbsp;</td>
<td>Invitrogen/Gibco</td>
<td>15070-063</td>
<td>&nbsp;</td>
<tr>
<td>Recombinant human basic fibroblast growth factor</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>13256-029</td>
<td>&nbsp;</td>
<tr>
<td>Beta-mercaptoethanol </td>
<td>&nbsp;</td>
<td>Invitrogen/Gibco</td>
<td>21985-023</td>
<td>&nbsp;</td>
<tr>
<td>Rabbit anti-human red blood cell primary antibody</td>
<td>&nbsp;</td>
<td>Rockland</td>
<td>109-4139</td>
<td>&nbsp;</td>
<tr>
<td>Guinea-pig complement serum</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S-1639</td>
<td>&nbsp;</td>
<tr>
<td>Capillary pipettes in 10 microL, 50 microL, 100 microL sizes</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Mouth pipettes with tubing</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>&nbsp;</td>
<td>supplied with capillary pipettes from VWR</td>
</tr>
<tr>
<td>0.2 microm Acrodisc syringe filter </td>
<td>&nbsp;</td>
<td>Pall Life Sciences</td>
<td>PN4192</td>
<td>&nbsp;</td>
<tr>
<td>0.5% Trypsin-EDTA</td>
<td>&nbsp;</td>
<td>Invitrogen/Gibco</td>
<td>25300-120</td>
<td>&nbsp;</td>
<tr>
<td>Tissue culture dishes</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Tissue culture dishes</td>
<td>&nbsp;</td>
<td>NUNC</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Nikon SMZ1500 dissection scope equipped with Nikon Tokai Hit ThermoPlate warming stage </td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Mouse embryonic fibroblasts (E12.5)</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

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. 


Watch this Scientific Journal Video about Derivation of Human Embryonic Stem Cells by Immunosurgery at JoVE.com

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 ...

derivation-of-human-embryonic-stem-cells-by-immunosurgery

Research

JoVE Journal

Biology

33.6K Views.  Harvard. 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.

Video: Derivation of Human Embryonic Stem Cells by Immunosurgery

Propagation of Human Embryonic Stem (ES) Cells

Propagation of Human Embryonic Stem ES Cells

Derivation of Hematopoietic Stem Cells from Murine Embryonic Stem Cells

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are derived from the blastocyst of the early embryo and are pluripotent in differentiative ability.  Their vast differentiative potential has made them the focus of much research centered on deducing how to coax them to generate clinically useful cell types.  The successful derivation of hematopoietic stem cells (HSC) from mouse ESC has recently been accomplished and can be visualized in this video protocol.  HSC, arguably the most clinically exploited cell population, are used to treat a myriad of hematopoietic malignancies and disorders.  However, many patients that might benefit from HSC therapy lack access to suitable donors.  ESC could provide an alternative source of HSC for these patients.  The following protocol establishes a baseline from which ESC-HSC can be studied and inform efforts to isolate HSC from human ESC.  In this protocol, ESC are differentiated as embryoid bodies (EBs) for 6 days in commercially available serum pre-screened for optimal hematopoietic differentiation.  EBs are then dissociated and infected with retroviral HoxB4.  Infected EB-derived cells are plated on OP9 stroma, a bone marrow stromal cell line derived from the calvaria of  M-CSF-/- mice, and co-cultured in the presence of hematopoiesis promoting cytokines for ten days.  During this co-culture, the infected cells expand greatly, resulting in the generation a heterogeneous pool of 100s of millions of cells.  These cells can then be used to rescue and reconstitute lethally irradiated mice.

This protocol details the derivation of transplantable hematopoietic stem cells from mouse embryonic stem cells (ESC) and their subsequent injection into lethally irradiated recipient mice. Briefly, ESC are differentiated as embryoid bodies, which are then infected with retroviral HoxB4 and co-cultured with OP9 stromal cells and hematopoietic cytokines.

A stem cell is defined as a cell with the capacity to both self-renew and generate multiple differentiated progeny.  Embryonic stem cells (ESC) are ...

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.

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.

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.

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.

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.

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 ...

Isolation and Derivation of Mouse Embryonic Germinal Cells

The ability of embryonic germinal cells (EG) to differentiate into primordial germinal cells (PGCs) and later into gametes during early developmental stages is a perfect model to address our hypothesis about cancer and infertility. This protocol shows how to isolate primordial germinal cells from developing gonads in 10.5-11.5 days post coitum (dpc) mouse embryos.  Developing gonadal ridges from mouse embryos (C57BL6J) were dissociated by mechanical disruption with collagenase, then plated in a mouse embryo fibroblast feeder layer (MEF-CF1) that was previously mitotically inactivated with mitomycin C in the presence of knockout media and supplemented with Leukemia Inhibitor Factor (LIF), basic Fibroblast Growth Factor (bFGF), and Stem Cell Factor (SCF).  Using these optimized methods for PCG identification, isolation, and establishment of culture conditions permits long term cultures of EG cells for more than 40 days.  The embryonic germinal cell lines showed embryonic phenotype and expression of common used markers of the pluripotent state.  Isolation and derivation of germinal cells in culture provide a tool to understand their development in vitro and offer the opportunity to monitor cumulative damage at genetic and epigenetic levels after exposure to oxidative stress.

The ability of embryonic germinal cells to differentiate into primordial germinal cells during early development stages is a perfect model to address our hypothesis about cancer and infertility. This protocol shows how to isolate primordial germinal cells from developing gonads in 10.5-11.5 days post coitum mouse embryos.

The ability of embryonic germinal cells (EG) to differentiate into primordial germinal cells (PGCs) and later into gametes during early developmental ...

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.

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

Derivation of Mouse Trophoblast Stem Cells from Blastocysts

Specification of the trophectoderm is one of the earliest differentiation events of mammalian development. The trophoblast lineage derived from the trophectoderm mediates implantation and generates the fetal part of the placenta. As a result, the development of this lineage is essential for embryo survival. Derivation of trophoblast stem (TS) cells from mouse blastocysts was first described by Tanaka et al. 1998. The ability of TS cells to preserve the trophoblast specific property and their expression of stage- and cell type-specific markers after proper stimulation provides a valuable model system to investigate trophoblast lineage development whereby recapitulating early placentation events. Furthermore, trophoblast cells are one of the few somatic cell types undergoing natural genome amplification. Although the molecular pathways underlying trophoblast polyploidization have begun to unravel, the physiological role and advantage of trophoblast genome amplification remains largely elusive. The development of diploid stem cells into polyploid trophoblast cells in culture makes this ex vivo system an excellent tool for elucidating the regulatory mechanism of genome replication and instability in health and disease. Here we describe a protocol based on previous reports with modification published in Chiu et al. 2008.

In this video, we demonstrate the isolation of mouse blastocysts and the derivation of trophoblast stem cells from blastocysts. We also describe conditions for maintenance of the stem cell property as well as induction of differentiation in culture.

Specification of the trophectoderm is one of the earliest differentiation events of mammalian development. The trophoblast lineage derived from the ...