Etichettatura di manganese di cellule staminali embrionali umane <ol><li> Trypsinize i gambi embrionali umane che sono state coltivate in alimentazione priva di condizioni per 5 minuti. Neutralizzare la tripsina aggiungendo terreni di coltura. </li><li> Spin giù le cellule per centrifugazione a 800 rpm per 5 minuti a 20 ° Celsius. Dopo aver ri-sospendere il pellet di cellule, contare il numero di celle trypan colorazione blu. Sulla base della conta delle cellule ottenute, dividere le cellule in quattro aliquote di 3 milioni di cellule in provette coniche. Agglomerare le cellule di nuovo per centrifugazione. </li><li> Appena prima di iniziare l&#39;etichettatura manganese, sciogliere fresco con una soluzione di cloruro di manganese, sodio cloruro 0,9% per ottenere una soluzione di cloruro di manganese 0,1 mm. </li><li> Al fine di osservare l&#39;attività dei canali del calcio, quattro campioni sono stati preparati. Il primo esempio è il nostro controllo che contiene le cellule incubate nello 0,9% di cloruro di sodio da solo. Il secondo campione contiene cellule incubate in 0,1 mM MnCl 2. Esempio 3 e 4 contengono cellule incubate in mM MnCl 0,1 2 sia con 5 micron di Ca 2 + canali agonista, (s )-(-)- Bay K8644, o 250 mM di Ca 2 + canali antagonista, verapamil. Incubare i quattro campioni a 37 ° C con 5% di CO 2 per 30 minuti. </li><li> Dopo 30 minuti, centrifugare le cellule a 800 rpm per 5 minuti a 20 ° Celsius. Poi aspirare il surnatante e lavare le cellule marcate due volte con PBS. Dopo il lavaggio, risospendere ogni pellet con 200 l di PBS e trasferimento in provette PCR. Questi granuli sono generalmente bianchi. </li></ol> Etichettatura di ferro di cellule staminali embrionali umane <ol><li> Mix clinico-grade solfato di protamina con acqua distillata per ottenere un 1 mg / ml soluzione madre. </li><li> In una provetta contenente staminali embrionali umane terreni di coltura di cellule, aggiungere ferumoxides a 100 mg / ml seguito da aggiunta di 12 mg / ml di solfato di protamina. Miscelare la soluzione vigorosamente per cinque minuti. </li><li> Aggiungi soluzione mista alla quantità uguale di terreni di coltura della cellula di raggiungere una concentrazione finale di 50 mg / ml di ferumoxides e 6 mg / mL di solfato di protamina alle cellule etichetta. Incubare le cellule in questa soluzione per 12 ore. </li><li> Lavare le cellule due volte con PBS, con l&#39;ultimo lavaggio contenenti eparina 10U/ml di sciogliere la extracellulare ferumoxides-protamina solfato complesso. Dopo il lavaggio, trypsinize cellule per ottenere una sospensione singola cellula. </li><li> Contare le celle e aliquota nel numero di campioni. Dopo il lavaggio, risospendere ogni pellet con 200 l di PBS e trasferimento in provette PCR. Questi pellet dovrebbe essere arancione scuro di colore marrone. </li></ol> Esecuzione di Cellular risonanza magnetica <ol><li> Fai un fantasma al fine di stabilizzare i tubi contenenti il ​​pellet cellulare e anche per evitare artefatti da l&#39;aria circostante durante la scansione. Per farlo, mescolare 0,8% di agar e l&#39;1% di solfato di rame in acqua distillata e portare ad ebollizione per microonde per 5-7 minuti. Raffreddare il composto per almeno 1 ora prima della scansione per ottenere un gel. </li><li> I tubi contenenti i pellet cella etichettata vengono inseriti nella fantasma per la scansione. In vitro cellulare risonanza magnetica viene eseguita a 3T MRI Signa HDx (GE Medical Systems) utilizzando bobina clinico del ginocchio. </li><li> Scansione le cellule manganese etichettati per ciascuno dei tre campioni utilizzando una sequenza spin echo: TR, tempo di ripetizione = 800 msec. TE; tempo Echo = minimo, FOV, campo di vista = 12 x 12 cm; matrice = 256x256, NEX 1. </li><li> Scansione le cellule ferro etichettati utilizzando un gradiente-echo. Noi utilizzare i seguenti parametri per questo l&#39;imaging: TR = 100 msec; = 30 ° angolo di vibrazione;; FOV = 12 x 12 cm; matrice = 256 x 256, NEX 1 TE = 10 msec, FA. </li></ol> Analisi dei risultati MRI <ol><li> Analizzare le immagini di risonanza magnetica da 4 diversi campioni di cellule manganese marcato: <ul><li> Esempio # 1 è il nostro controllo che contiene cellule incubate nello 0,9% di cloruro di sodio da solo. </li><li> Esempio # 2 contiene cellule incubate in 0,1 mM MnCl 2. </li><li> Esempio # 3 contiene cellule incubate in mM MnCl 0,1 2 con 5 mM di Ca 2 + canali agonista, (s )-(-)- Bay K8644. </li><li> Esempio # 4 contiene cellule incubate in mM MnCl 0,1 2 con 250 mM di Ca 2 + canali antagonista, verapamil. </li></ul></li><li> Come previsto, le differenze di intensità di segnale da manganese cellule marcate sono visibili. Rispetto alle cellule etichettate esclusivamente con manganese, l&#39;intensità del segnale aumenta chiaramente in presenza di agonisti dei canali del calcio e diminuisce in presenza di antagonista dei canali del calcio. L&#39;area in cui l&#39;intensità del segnale è aumentata per il manganese cellule marcate sono misurati utilizzando immagini J (NIH, Bethesda, MD, USA). Lo stesso software viene utilizzato per analizzare la zona di buio fuori risonanza segnale dal ferro cellule marcate. La dimensione del segnale scuro dal ferro marcato le cellule dipende dal numero di cellule o il numero di particelle di ferro contenuta da parte delle cellule. In questo caso, Un milione di cellule mostra un&#39;area più piccola di segnale scuro rispetto al segnale dai tre milioni di celle. </li></ol>

<ol>
	<li>Bruvold, M., Nordhoy, W., Anthonsen, H. W., Brurok, H., Jynge, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Manganese-calcium+interactions+with+contrast+media+for+cardiac+magnetic+resonance+imaging:+a+study+of+manganese+chloride+supplemented+with+calcium+gluconate+in+isolated+Guinea+pig+hearts.">Manganese-calcium interactions with contrast media for cardiac magnetic resonance imaging: a study of manganese chloride supplemented with calcium gluconate in isolated Guinea pig hearts.</a> Invest Radiol. 40, 117-125 (2005).</li><li>Aoki, I., 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=Cell+labeling+for+magnetic+resonance+imaging+with+the+T1+agent+manganese+chloride.">Cell labeling for magnetic resonance imaging with the T1 agent manganese chloride.</a> NMR Biomed. 19, 50-59 (2006).</li><li>Arbab, A. 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=Efficient+magnetic+cell+labeling+with+protamine+sulfate+complexed+to+ferumoxides+for+cellular+MRI.">Efficient magnetic cell labeling with protamine sulfate complexed to ferumoxides for cellular MRI.</a> Blood. 104, 1217-1223 (2004).</li><li>Arbab, A. S., Frank, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+MRI+and+its+role+in+stem+cell+therapy.">Cellular MRI and its role in stem cell therapy.</a> Regen Med. 3, 199-215 (2008).</li></ol>

Questi risultati indicano che il manganese si entra attraverso il voltaggio-dipendente dei canali del calcio, manganese e può essere usato come agente di contrasto per risonanza magnetica, che può anche mostrare la vitalità cellulare. Pertanto, si consiglia di manganese-guidata risonanza magnetica può essere utile per monitorare la vitalità cellulare dopo il trapianto di cellule staminali embrionali umane nel miocardio.

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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>Manganese chloride tetrahydrate</td>
<td>Reagent</td>
<td>Sigma</td>
<td>M8054</td>
<td>&nbsp;</td>
<tr>
<td>(S)-(-)-Bay K8644 </td>
<td>Reagent</td>
<td>Sigma</td>
<td>B133</td>
<td>&nbsp;</td>
<tr>
<td>(+)-Verapamil hydrochloride, minimum 99.0% titration </td>
<td>Reagent</td>
<td>Sigma</td>
<td>V4629</td>
<td>&nbsp;</td>
<tr>
<td>Sodium Chloride 0.85-0.90% W/V</td>
<td>Reagent</td>
<td>VWR</td>
<td>VW 3257-1</td>
<td>&nbsp;</td>
<tr>
<td>Feridex I.V. </td>
<td>Reagent</td>
<td>Berlex Laboratories</td>
<td>NDC 59338-7035-5</td>
<td>ferumoxides injectable solution 11.2mg iron/mL</td>
</tr>
<tr>
<td>Protamine sulfate</td>
<td>Reagent</td>
<td>American Pharmaceutical Partners</td>
<td>NDC 63323-229-05 </td>
<td>50 mg (10 mg/mL)</td>
</tr>
<tr>
<td>Knockout SR (Serum replacement for ES cells)</td>
<td>Reagent</td>
<td>Gibco</td>
<td>10828</td>
<td>&nbsp;</td>
<tr>
<td>DMEM/F12 (1:1)</td>
<td>Reagent</td>
<td>Gibco</td>
<td>11330</td>
<td>&nbsp;</td>
<tr>
<td>2- mercaptoethanol 98+%</td>
<td>Reagent</td>
<td>Sigma</td>
<td>M 3148</td>
<td>&nbsp;</td>
<tr>
<td>L-Glutamine 200mM 100x</td>
<td>Reagent</td>
<td>Gibco</td>
<td>25030</td>
<td>&nbsp;</td>
<tr>
<td>Penicillin-Streptomyocin 10,000 units/ml</td>
<td>Reagent</td>
<td>Gibco</td>
<td>15140-122</td>
<td>&nbsp;</td>
<tr>
<td>MEM Non-Essential Amino Acids 100x solution</td>
<td>Reagent</td>
<td>Gibco </td>
<td>11140</td>
<td>&nbsp;</td>
<tr>
<td>Signa HDx 3T MRI</td>
<td>Tool</td>
<td>GE Medical Systems</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>clinical Knee coil</td>
<td>Tool</td>
<td>GE Medical Systems</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>DPBS</td>
<td>Reagent</td>
<td>Gibco</td>
<td>14190</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

in vitro labeling of human embryonic stem cells for magnetic resonance imaging

Cellule staminali embrionali umane (hESC) hanno dimostrato la capacità di ripristinare i feriti miocardio. Risonanza magnetica (MRI) è emerso come una delle modalità di imaging predominante per valutare il restauro dei feriti miocardio. Inoltre, ex-vivo agenti etichettatura, come ad esempio nanoparticelle di ossido di ferro, sono stati impiegati per tracciare e localizzare le cellule staminali trapiantate. Tuttavia, questo metodo non controlla una proprietà fondamentale della biologia cellulare per quanto riguarda la vitalità delle cellule trapiantate. È noto che il cloruro di manganese (MnCl 2) entra nelle cellule attraverso voltaggio-dipendenti del calcio (Ca 2 +) canali quando le cellule sono biologicamente attivi e si accumula nelle cellule per generare T 1 effetto accorciamento. Pertanto, si consiglia di manganese-guidata risonanza magnetica può essere utile per monitorare la vitalità cellulare dopo il trapianto di hESC nel miocardio. In questo video, ci mostrerà come etichetta hESC con MnCl 2 e come queste cellule può essere vista chiaramente utilizzando la risonanza magnetica in vitro. Allo stesso tempo, l&#39;attività biologica di Ca 2 +-canali saranno modulati utilizzando sia Ca 2 + canali agonista e antagonista per valutare le variazioni del segnale concomitanti.

Watch this Scientific Journal Video about In vitro Labeling of Human Embryonic Stem Cells for Magnetic Resonance Imaging at JoVE.com

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

In questo video, ci mostra come etichetta cellule staminali embrionali umane (hESC) con cloruro di manganese (MnCl<sub&gt; 2</sub&gt;), Che possono entrare nelle cellule attraverso i canali voltaggio-dipendenti del calcio quando le cellule sono biologicamente attivi. Inoltre, ci mostrano l&#39;uso di MnCl<sub&gt; 2</sub&gt; Cellulare come agente di contrasto per risonanza magnetica per determinare la fattibilità in vitro di hESC.

Etichettatura in vitro di cellule staminali embrionali umane per la Risonanza Magnetica

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

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10.1K Views.  Stanford University. In questo video, ci mostra come etichetta cellule staminali embrionali umane (hESC) con cloruro di manganese (MnCl 2), Che possono entrare nelle cellule attraverso i canali voltaggio-dipendenti del calcio quando le cellule sono biologicamente attivi. Inoltre, ci mostrano l'uso di MnCl 2 Cellulare come agente di contrasto per risonanza magnetica per determinare la fattibilità in vitro di hESC.

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

Propagation of Human Embryonic Stem (ES) Cells

Propagation of Human Embryonic Stem ES Cells

Propagazione di staminali embrionali umane (ES) Cellule

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Biologia

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.

Derivazione di cellule staminali embrionali umane da 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 ...

Labeling Stem Cells with Fluorescent Dyes for non-invasive Detection with Optical Imaging

Optical imaging (OI) is an easy, fast and inexpensive tool for in vivo monitoring of new stem cell based therapies. The technique is based on ex vivo labeling of stem cells with a fluorescent dye, subsequent intravenous injection of the labeled cells and visualization of their accumulation in specific target organs or pathologies. The presented technique demonstrates how we label human mesenchymal stem cells (hMSC) by simple incubation with the lipophilic fluorescent dye DiD (C67H103CIN2O3S) and how we label human embryonic stem cells (hESC) with the FDA approved fluorescent dye Indocyanine Green (ICG). The uptake mechanism is via adherence and diffusion of the lypophilic dye across the phospholipid cell membrane bilayer. The labeling efficiency is usually improved if the cells are incubated with the dye in serum-free media as opposed to incubation in serum-containing media. Furthermore, the addition of the transfection agent Protamine Sulfate significantly improves contrast agent uptake.

This video shows techniques for labeling of human embryonic stem cells and mesenchymal stem cells with fluorescent dyes. This technique can be used for an in vivo tracking of transplanted stem cells with optical imaging and for histopathological correlations with fluorescence microscopy.

Etichettatura Cellule staminali con le tinture fluorescenti per la rilevazione non invasiva con Optical Imaging

Optical imaging (OI) is an easy, fast and inexpensive tool for in vivo monitoring of new stem cell based therapies. The technique is based on ex vivo ...

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.

Sondaggio per mitocondriale complessa attività di cellule staminali embrionali umane

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

In vitro and in vivo Bioluminescence Reporter Gene Imaging of Human Embryonic Stem Cells

The discovery of human embryonic stem cells (hESCs) has dramatically increased the tools available to medical scientists interested in regenerative medicine. However, direct injection of hESCs, and cells differentiated from hESCs, into living organisms has thus far been hampered by significant cell death, teratoma formation, and host immune rejection. Understanding the in vivo hESC behavior after transplantation requires novel imaging techniques to longitudinally monitor hESC localization, proliferation, and viability. Molecular imaging has given investigators a high-throughput, inexpensive, and sensitive means for tracking in vivo cell proliferation over days, weeks, and even months. This advancement has significantly increased the understanding of the spatio-temporal kinetics of hESC engraftment, proliferation, and teratoma-formation in living subjects.

A major advance in molecular imaging has been the extension of noninvasive reporter gene assays from molecular and cellular biology into in vivo multi-modality imaging platforms. These reporter genes, under control of engineered promoters and enhancers that take advantage of the host cell s transcriptional machinery, are introduced into cells using a variety of vector and non-vector methods. Once in the cell, reporter genes can be transcribed either constitutively or only under specific biological or cellular conditions, depending on the type of promoter used. Transcription and translation of reporter genes into bioactive proteins is then detected with sensitive, noninvasive instrumentation (e.g., CCD cameras) using signal-generating probes such as D-luciferin.

To avoid the need for excitatory light to track stem cells in vivo as is required for fluorescence imaging, bioluminescence reporter gene imaging systems require only an exogenously administered probe to induce light emission. Firefly luciferase, derived from the firefly Photinus pyralis, encodes an enzyme that catalyzes D-luciferin to the optically active metabolite, oxyluciferin. Optical activity can then be monitored with an external CCD camera. Stably transduced cells that carry the reporter construct within their chromosomal DNA will pass the reporter construct DNA to daughter cells, allowing for longitudinal monitoring of hESC survival and proliferation in vivo. Furthermore, because expression of the reporter gene product is required for signal generation, only viable parent and daughter cells will create bioluminescence signal; apoptotic or dead cells will not. 

In this video, the specific materials and methods needed for tracking stem cell proliferation and teratoma formation with bioluminescence imaging will be described.

With the growing interest in stem cell therapies, molecular imaging techniques are ideal for monitoring stem cell behavior after transplantation. Luciferase reporter genes have enabled non-invasive, repetitive assessment of cell survival, location, and proliferation in vivo. This video will demonstrate how to track hESC proliferation in a living mouse.

In vitro e in Imaging bioluminescenza gene reporter in vivo di cellule staminali embrionali umane

The discovery of human embryonic stem cells (hESCs) has dramatically increased the tools available to medical scientists interested in regenerative ...

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.

Immunoprecipitazione della cromatina di cellule staminali embrionali umane

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.

Cultura e manutenzione di cellule staminali embrionali umane

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.

Preparazione Stendere cromosomiche di cellule staminali embrionali umane per cariotipo

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.

Congelamento e scongelamento cellule staminali embrionali umane

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 ...

Video Bioinformatics Analysis of Human Embryonic Stem Cell Colony Growth

Because video data are complex and are comprised of many images, mining information from video material is difficult to do without the aid of computer software.  Video bioinformatics is a powerful quantitative approach for extracting spatio-temporal data from video images using computer software to perform dating mining and analysis. In this article, we introduce a video bioinformatics method for quantifying the growth of human embryonic stem cells (hESC) by analyzing time-lapse videos collected in a Nikon BioStation CT incubator equipped with a camera for video imaging. In our experiments, hESC colonies that were attached to Matrigel were filmed for 48 hours in the BioStation CT.  To determine the rate of growth of these colonies, recipes were developed using CL-Quant software which enables users to extract various types of data from video images.  To accurately evaluate colony growth, three recipes were created. The first segmented the image into the colony and background, the second enhanced the image to define colonies throughout the video sequence accurately, and the third measured the number of pixels in the colony over time.  The three recipes were run in sequence on video data collected in a BioStation CT to analyze the rate of growth of individual hESC colonies over 48 hours. To verify the truthfulness of the CL-Quant recipes, the same data were analyzed manually using Adobe Photoshop software. When the data obtained using the CL-Quant recipes and Photoshop were compared, results were virtually identical, indicating the CL-Quant recipes were truthful. The method described here could be applied to any video data to measure growth rates of hESC or other cells that grow in colonies. In addition, other video bioinformatics recipes can be developed in the future for other cell processes such as migration, apoptosis, and cell adhesion.  

Video bioinformatics is the automated processing, analysis, understanding, and data mining of biological spatio-temporal data extracted from microscopic videos. The purpose of this article is to demonstrate a method for measuring human embryonic stem cell colony growth using a video bioinformatics method.

Video Bioinformatica Analisi delle embrionali umane crescita Colony cellule staminali

Because video data are complex and are comprised of many images, mining information from video material is difficult to do without the aid of computer ...