Ce travail a été rendu possible par la Fondation Human Tissue et recherche sur les cellules, ce qui rend les tissus humains disponibles pour la recherche. Le soutien financier pour ce travail a été reçu par le ministère fédéral de l&#39;éducation et de la recherche (nom de subvention: Virtual foie réseau, le numéro de subvention: 0315759) et Hepacult GmbH. Nos remerciements vont également aux assistants techniques de la banque de tissus Hôpital Grosshadern pour la collecte des échantillons de foie et les assistants techniques de la cellule d&#39;isolement de base Facilité pour la réalisation de la perfusion du foie et de l&#39;isolement des hépatocytes. En particulier, nous tenons à remercier Natalja Löwen pour démontrer cette procédure dans la vidéo. Enfin, nous tenons à remercier Natalja Löwen et Edeltraud Hanesch pour créer des illustrations de la Figure 1 et les chiffres dans la vue d&#39;ensemble schématique de la vidéo.

Une. Préparation de la perfusion et l&#39;isolement Solutions <ol><li> Préparer les solutions nécessaires pour la perfusion de la pièce de foie et de l&#39;isolement des hépatocytes, conformément au tableau 1. Les solutions peuvent être stockées à 4 ° C jusqu&#39;à utilisation. </li><li> Filtre stérile toutes les solutions en utilisant un filtre de 0,22 um. </li><li> Toutes les solutions qui viennent en contact avec le foie doivent être stériles. </li></ol> 2. Préparation de l&#39;équipement et des solutions de perfusion <ol><li> L&#39;équipement pour la perfusion de la pièce de foie doit être mis en place comme représenté sur la figure 1. </li><li> Le bain d&#39;eau doit être réglée à une température appropriée, qui est différent dans chaque montage expérimental particulier, tel que les solutions sont à la température de 37 ° C quand ils atteignent la pièce de foie. Dans ce cas, le bain d&#39;eau est réglée à 41 ° C pour chauffer les solutions 1, 2 et 3 et le condenseur en verre à double enveloppe. Solution 4 doit être réchauffé à37 ° C dans un bain d&#39;eau séparée pour utilisation pour réduire la perte d&#39;activité de la collagénase. </li><li> Peu de temps avant la perfusion du foie, mettez le régulateur du réservoir de gaz contenant 95% d&#39;O 2/5% de CO 2 au gaz de l&#39;appareil d&#39;oxygénation (figure 1E). </li></ol> 3. Perfusion du foie <ol><li> Un morceau de foie avec autant capsule intacte de Glisson que possible et idéalement avec une surface de seulement 1 coupe doit être obtenue à partir d&#39;un pathologiste pour perfusion. </li><li> Placer cette pièce de foie sur l&#39;entonnoir Büchner qui contient un disque de filtre perforé (figure 1B). </li><li> Le système de perfusion doit être amorcée avec la solution 1. </li><li> Avec une vitesse d&#39;écoulement faible, incurvée canules d&#39;irrigation avec des embouts d&#39;olive doit être inséré dans les vaisseaux sanguins plus grands sur la surface de la pièce de foie de coupe. Comme le sang évacue par le foie, le tissu devient plus léger dans les zones avec une bonne perfusion. Le nombre de canules utilisées pour différentes taillesdes foies est représenté sur la figure 2A. La taille de la jauge choisie devrait se traduire par un ajustement confortable qui tiendra les canules à la place. Les vaisseaux sanguins plus petits doivent être laissés ouverts pour le tampon de perfusion à s&#39;écouler hors de la pièce de foie. </li><li> Augmenter le débit de la pompe péristaltique à entre 110 à 460 ml / min selon la taille du foie (Figure 2B). Il en résulte un débit moyen de 44 ± 16 ml / min par la canule (figure 2C). La vitesse choisie est fonction de la pièce de foie et devrait se traduire par une légère repulpant place de la pièce de foie. Dans certains cas, il peut être nécessaire de serrer fermer certains des récipients ouverts avec des micro clamps vasculaires pour atteindre la légère repulpant mentionné ci-dessus. Une bonne perfusion peut être observé lorsque la pièce de foie est une couleur plus claire partout. </li><li> Gardez la pièce humide du foie pendant la perfusion en le recouvrant d&#39;un morceau de gaze trempé dans une solution saline. </li><li> Perfuser avec 1 L de solution 1 pour débusquer tout remaining sang dans la pièce du foie. </li><li> Changer le liquide de perfusion à la solution 2 et perfuser pendant 10 min. </li><li> Commuter le liquide de perfusion pour perfuser la solution 3 et avec 0,5 L. </li><li> Changer le liquide de perfusion de la solution 4, qui contient de 0,1 à 0,15% de collagénase (Tableau 2). </li><li> Pour cette étape, la perfusion doit être effectuée de manière à recirculation pour 9-12 minutes ou jusqu&#39;à ce que le foie est suffisamment digéré, le tissu du foie devrait apparaître à briser un peu moins de la capsule de Glisson et sentir ramolli lorsque sondé avec le côté émoussé d&#39;un scalpel. </li></ol> 4. Isolement des hépatocytes <ol><li> Arrêter la pompe péristaltique et retirer les canules de la pièce de foie. </li><li> Placez le morceau de foie dans un cristallisoir contenant 100-200 ml de solution 5. </li><li> Retirez la capsule de Glisson soigneusement et secouez doucement les cellules. Si il ya des régions qui ne sont pas bien perfusés, un scalpel peut être utilisé pour couper à traversces régions pour libérer les cellules contenues à l&#39;intérieur. Ajouter plus de solutions 5 au besoin pendant le processus. </li><li> Ajouter plus de solution 5 jusqu&#39;à un volume final de 500 ml est atteinte. </li><li> Filtrer la suspension de cellules à deux reprises, d&#39;abord à travers une maille de 210 um de nylon suivi d&#39;un filet de nylon de 70 um. Ensuite, versez la suspension de cellules dans 200 ml tubes de centrifugation. </li><li> Centrifuger la suspension cellulaire à 72 g pendant 5 min à 4 ° C. Aspirer le surnageant et le culot de cellules doucement remis en suspension doucement dans 200 ml de Solution 5. </li><li> Répéter le lavage numéro de l&#39;étape 4.6 à trois reprises. Sur l&#39;étape de centrifugation finale, les cellules remettre en suspension dans une solution de stockage à froid (voir la liste des matériaux). Les cellules doivent être d&#39;environ 2,5 millions hépatocytes par millilitre pour l&#39;évaluation du rendement et la viabilité en utilisant un trypan test d&#39;exclusion au bleu en fonction de hématimètre. </li><li> Pour effectuer un test d&#39;exclusion au bleu trypan, ajouter 0,1 ml de cellules diluées de manière appropriée (≈ 2-5 millions / ml) dans un tube de centrifugeuse contenant 0,5 ml de soluti bleu trypanle (0,4% de bleu trypan dissous dans une solution saline tamponnée au phosphate (PBS)) et 0,4 ml de PBS. Après avoir mélangé la suspension de cellules à fond, charger un hémocytomètre avec la suspension et examiner au microscope à un grossissement de 100X. En microscopie, les cellules mortes seront colorées en bleu tandis que les cellules vivantes apparaissent sans tache. Compter le nombre de cellules vivantes et totales dans chacun des 1 mm 2 grilles marquées sur la hématimètre. Viabilité (%), le rendement des cellules vivantes (en millions hépatocytes par une solution de stockage à froid ml (CSS) ou million hépatocytes par g de foie) peut être calculé en utilisant les formules ci-dessous. </li></ol><img alt="Equation 1" fo:src="/files/ftp_upload/50615/50615eq1highres.jpg" src="/files/ftp_upload/50615/50615eq1.jpg" /> Remarque: Dans ce cas, le bleu trypan facteur de dilution est de 10 et le facteur de hématimètre est 10000.

<ol>
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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-yield+preparation+of+isolated+rat+liver+parenchymal+cells:+a+biochemical+and+fine+structural+study.">High-yield preparation of isolated rat liver parenchymal cells: a biochemical and fine structural study.</a> The Journal of Cell Biology. 43, 506-520 (1969).</li><li>Seglen, P. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+Rat-Liver+Cells+.3.+Enzymatic+Requirements+for+Tissue+Dispersion.">Preparation of Rat-Liver Cells .3. Enzymatic Requirements for Tissue Dispersion.</a> Experimental Cell Research. 82 (73), 391-398 (1973).</li><li>Thasler, W. E., 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=Charitable+State-Controlled+Foundation+Human+Tissue+and+Cell+Research:+Ethic+and+Legal+Aspects+in+the+Supply+of+Surgically+Removed+Human+Tissue+For+Research+in+the+Academic+and+Commercial+Sector+in+Germany.">Charitable State-Controlled Foundation Human Tissue and Cell Research: Ethic and Legal Aspects in the Supply of Surgically Removed Human Tissue For Research in the Academic and Commercial Sector in Germany.</a> Cell and Tissue Banking. 4, 49-56 (2003).</li><li>Queral, A. E., DeAngelo, A. B., Garrett, C. 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Leukocyte Biol. 38, 213-230 (1985).</li><li>Cantrell, E., Bresnick, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Benzpyrene+Hydroxylase-Activity+in+Isolated+Parenchymal+and+Nonparenchymal+Cells+of+Rat-Liver.">Benzpyrene Hydroxylase-Activity in Isolated Parenchymal and Nonparenchymal Cells of Rat-Liver.</a> Journal of Cell Biology. 52, 316-321 (1972).</li><li>Weiskirchen, R., Gressner, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+culture+of+hepatic+stellate+cells.">Isolation and culture of hepatic stellate cells.</a> Methods in Molecular Medicine. 117, 99-113 (2005).</li><li>Baccarani, U., 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=Steatotic+versus+cirrhotic+livers+as+a+source+for+human+hepatocyte+isolation.">Steatotic versus cirrhotic livers as a source for human hepatocyte isolation.</a> Transplant P. 33, 664-665 (2001).</li><li>Renz, J. F., 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=Utilization+of+extended+donor+criteria+liver+allografts+maximizes+donor+use+and+patient+access+to+liver+transplantation.">Utilization of extended donor criteria liver allografts maximizes donor use and patient access to liver transplantation.</a> Annals of Surgery. 242, 556-563 (2005).</li><li>Schemmer, P., 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=Extended+donor+criteria+have+no+negative+impact+on+early+outcome+after+liver+transplantation:+a+single-center+multivariate+analysis.">Extended donor criteria have no negative impact on early outcome after liver transplantation: a single-center multivariate analysis.</a> Transplant Proc. 39, 529-534 (2007).</li><li>Alexandre, E., 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=Influence+of+pre-,+intra-+and+post-operative+parameters+of+donor+liver+on+the+outcome+of+isolated+human+hepatocytes.">Influence of pre-, intra- and post-operative parameters of donor liver on the outcome of isolated human hepatocytes.</a> Cell and Tissue Banking. 3, 223-233 (2002).</li><li>Spotnitz, W. D., Burks, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=State-of-the-art+review:+Hemostats,+sealants,+and+adhesives+II:+Update+as+well+as+how+and+when+to+use+the+components+of+the+surgical+toolbox.">State-of-the-art review: Hemostats, sealants, and adhesives II: Update as well as how and when to use the components of the surgical toolbox.</a> Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/Hemostasis. 16, 497-514 (2010).</li><li>Spotnitz, W. D., Burks, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hemostats,+sealants,+and+adhesives+III:+a+new+update+as+well+as+cost+and+regulatory+considerations+for+components+of+the+surgical+toolbox.">Hemostats, sealants, and adhesives III: a new update as well as cost and regulatory considerations for components of the surgical toolbox.</a> Transfusion. 52, 2243-2255 (2012).</li><li>Toriumi, D. M., Raslan, W. F., Friedman, M., Tardy, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Histotoxicity+of+cyanoacrylate+tissue+adhesives.+A+comparative+study.">Histotoxicity of cyanoacrylate tissue adhesives. A comparative study.</a> Archives of otolaryngology--head &amp; neck surgery. 116, 546-550 (1990).</li><li>Vinters, H. V., Galil, K. A., Lundie, M. J., Kaufmann, J. 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Optimisation de ce protocole a été partiellement financée par une subvention de Hepacult GmbH. Dr. Wolfgang Thasler est l&#39;un des fondateurs de Hepacult GmbH et demeure l&#39;un des membres du conseil d&#39;administration de cette société. L&#39;emploi de Maresa Demmel est partiellement par Hepacult. Maria Hauner est employé par Hepacult GmbH. Hepacult est une société biotechnologique spin-off de l&#39;Université, qui offre des hépatocytes humains avec le consentement et l&#39;accès libre à des fins de recherche.

Ce protocole conduit à l&#39;isolement d&#39;hépatocytes humains à forte viabilité et de la pureté. Afin de parvenir à ces résultats, il est important de commencer par une pièce appropriée de foie. Le morceau de foie devrait avoir la capsule de Glisson intact sur toutes les surfaces à l&#39;exception de une surface de coupe. Un autre facteur important est le lot particulier de collagénase utilisée, comme différents lots peuvent entraîner des différences marquées dans les viabilités des hépatocytes apr?...

A correction was made to: <a href="http://www.jove.com/video/50615/isolation-human-hepatocytes-two-step-collagenase-perfusion">Isolation of Human Hepatocytes by a Two-step Collagenase Perfusion Procedure </a>
The changes listed below have been made to Table 1.
1). In the recipe for Solution 2, the Final Concentration of EGTA has been changed from:
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td>EGTA&#160;</td>
			<td>0.1mM</td>
		</tr>
	</tbody>
</table>
to:
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td>EGTA&#160;</td>
			<td>1mM</td>
		</tr>
	</tbody>
</table>
2). In the recipes for Solution 3 and 4, the Final Concentration of Calcium chloride dihydrate has been changed from:
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td>Calcium chloride dihydrate&#160;</td>
			<td>0.5&#181;M</td>
		</tr>
	</tbody>
</table>
to:
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td>Calcium chloride dihydrate&#160;</td>
			<td>5mM</td>
		</tr>
	</tbody>
</table>

A correction was made to: Isolation of Human Hepatocytes by a Two-step Collagenase Perfusion Procedure.
The Final Concentration of EGTA in Solution 2 and the Final Concentration of Calcium chloride dihydrate in solutions 3 and 4 have been updated in Table 1.

Erratum: Isolation of Human Hepatocytes by a Two-step Collagenase Perfusion Procedure

Une suspension de cellules de foie peut être préparé à partir du foie par des méthodes mécaniques ou enzymatiques. Les méthodes mécaniques utilisées pour préparer les cellules du foie entier comprennent forcer le foie à travers une étamine 2, secouant un morceau de foie avec des perles de verre dans un shaker Kahn 3, en utilisant des homogénéisateurs de verre avec des pilons en vrac 4,5 etc Au fil des ans, les méthodes mécaniques ont baissé de favoriser raison des dommages à la membrane cellulaire et la perte de la fonction des hépatocytes isolés 6,7. Par conséquent, l&#39;utilisation d&#39;un procédé enzymatique est actuellement la principale méthode pour l&#39;isolement d&#39;hépatocytes. L&#39;isolement des hépatocytes en utilisant une méthode enzymatique a été considérablement améliorée lorsque Berry et Friend 8 perfusées la collagénase et la hyaluronidase dans le foie via la veine porte chez des rats. Ce processus de perfusion utilisé le système vasculaire pour permettre aux enzymes de venir en contact étroit avec la majorité des cellules, conduisant àune augmentation de 6 fois le rendement des hépatocytes 8. En outre, cette méthode a donné des cellules qui ont conservé leur intégrité structurelle, avec pratiquement aucune transformation de réticulum endoplasmique dans des vésicules isolées et aucun dommage mitochondrial 8. Cette méthode a été modifiée par une Seglen, pionnier une procédure de perfusion en deux étapes pour l&#39;isolation des cellules du foie. Dans cette procédure, le foie de rat est perfusé avec un tampon 2 + Ca libre suivie d&#39;une perfusion avec un tampon contenant de la collagénase de Ca 2 + 1. L&#39;élimination de Ca 2 + dans la première étape permet de perturber les desmosomes, tandis que l&#39;addition de Ca 2 + dans la deuxième étape est requise pour l&#39;activité de la collagénase 1,9 optimum. Étant donné que les travaux publiés décrite ci-dessus a été réalisée chez le rat, cet article vise à démontrer une procédure modifiée qui peut être utilisé pour l&#39;isolement des hépatocytes avec une grande viabilité de bourdonnementun foie. L&#39;utilisation d&#39;hépatocytes humains reste important pour la recherche de translation et de validation des expériences utilisant des modèles animaux. Les morceaux de foie humain utilisés dans cette étude ont été acquis avec le consentement de la gouvernance à travers la Fondation de tissus humains et de cellules de recherche, une fondation contrôlée par l&#39;État à but non lucratif 10. Après un pathologiste supprimé ce qui était nécessaire pour le diagnostic, des morceaux de foie ont été prélevés dans le tissu restant. Le tissu sectionnée par le pathologiste était morphologiquement tissus sains obtenus à partir des marges de résection après résection hépatique.

<table border="1">
	<tbody>
		<tr>
			<td>Name of Reagent/Material</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Bubble trap</td>
			<td>Ga&szlig;ner Glastechnik</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Glass jacketed condenser</td>
			<td>Ga&szlig;ner Glastechnik</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>41 &deg;C Water bath</td>
			<td>Julabo</td>
			<td>35723-H24/EG</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>37 &deg;C Water bath</td>
			<td>GFL</td>
			<td>1083</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Compressed gas cylinder (95 % O2/5 % CO2)</td>
			<td>Linde</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Gas permeable tubing</td>
			<td>Neolab</td>
			<td>2-4440</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Peristaltic pump</td>
			<td>Ismatec</td>
			<td>IP65</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Scalpel</td>
			<td>Feather</td>
			<td>320010</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Forceps</td>
			<td>Omnilab</td>
			<td>5171014</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Conical flasks 1 L</td>
			<td>Schott Duran</td>
			<td>2121654</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Conical flasks 5 L</td>
			<td>Schott Duran</td>
			<td>2121673</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Beakers</td>
			<td>Schott Duran</td>
			<td>2110654</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>200 ml centrifuge tubes</td>
			<td>Becton Dickinson</td>
			<td>352075</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Crystallizing dish</td>
			<td>Omnilab</td>
			<td>5144063</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Curved irrigation cannulae with ball tips</td>
			<td>Ernst Kratz GmbH</td>
			<td>1464LL/ 1465LL A+B/ 1472LL</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Micro vascular clamps</td>
			<td>Ernst Kratz GmbH</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>B&uuml;chner funnel</td>
			<td>Carl Roth</td>
			<td>HT38.1</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Nylon mesh 210 &mu;m</td>
			<td>Neolab</td>
			<td>4-1413</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Nylon mesh 70 &mu;m</td>
			<td>Neolab</td>
			<td>4-1419</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>0.22 &mu;m sterile filters</td>
			<td>Peske</td>
			<td>99505</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>500 ml bottles</td>
			<td>Schott Duran</td>
			<td>2180144</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>1 L bottles</td>
			<td>Schott Duran</td>
			<td>2180154</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Hemocytometer</td>
			<td>Peske</td>
			<td>06-0001</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>1.5 ml tubes</td>
			<td>Eppendorf</td>
			<td>0030 120,086</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>50 ml conical tubes</td>
			<td>BD Biosciences</td>
			<td>352070</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Ice bucket</td>
			<td>Neolab</td>
			<td>1508454</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Sterile Pasteur pipettes</td>
			<td>Brand</td>
			<td>747715</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Motorised pipette filler (Pipette boy acu)</td>
			<td>Integra</td>
			<td>155017</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Refridgerated centrifuge</td>
			<td>Eppendorf</td>
			<td>5810R</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Laminar flow</td>
			<td>Kendro</td>
			<td>Hera safe-KS9</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Aspirator (Low-flow surgical suction pump)</td>
			<td>Atmos</td>
			<td>C361</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Laboratory Gas Burner</td>
			<td>Integra</td>
			<td>Fire Boy eco</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Disposable laboratory coat</td>
			<td>Paperlynen GmbH</td>
			<td>MD0202414</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Surgical mask with visor</td>
			<td>Kimberly-Clark</td>
			<td>48247</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Surgical hood</td>
			<td>Barrier</td>
			<td>42072</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Latex gloves</td>
			<td>Semper Care</td>
			<td>CE0321</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Collagenase (Batch number NB 4G)</td>
			<td>Serva</td>
			<td>17465</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Calcium chloride dihydrate</td>
			<td>Merck</td>
			<td>2382</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>EGTA</td>
			<td>Sigma</td>
			<td>E4378</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Sodium chloride</td>
			<td>Roth</td>
			<td>9265.2</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Hepes</td>
			<td>Roth</td>
			<td>9105.3</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Potassium chloride</td>
			<td>Serva</td>
			<td>26868</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Albumin</td>
			<td>Biomol</td>
			<td>01400-2</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Glucose</td>
			<td>Serva</td>
			<td>22700</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Sodium hydrogen carbonate</td>
			<td>Serva</td>
			<td>30180</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>0.4% Trypan blue solution</td>
			<td>Lonza</td>
			<td>17-942E</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Cold storage solution</td>
			<td>Hepacult GmbH</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

isolation of human hepatocytes by a two-step collagenase perfusion procedure

Le foie, un organe d&#39;une capacité de régénération exceptionnelle, effectue un large éventail de fonctions, telles que la désintoxication, le métabolisme et l&#39;homéostasie. En tant que tel, les hépatocytes sont un modèle important pour une grande variété de questions de recherche. En particulier, l&#39;utilisation d&#39;hépatocytes humains est particulièrement important dans les domaines de la pharmacocinétique, la toxicologie, la régénération du foie et de la recherche de translation. Ainsi, ce procédé présente une version modifiée d&#39;une procédure de perfusion de collagénase en deux étapes pour isoler les hépatocytes, comme décrit par une Seglen. Auparavant, les hépatocytes ont été isolés par des méthodes mécaniques. Cependant, les méthodes enzymatiques ont été montré supérieur hépatocytes conservent leur intégrité et leur fonction structurale après isolement. Cette méthode présentée ici adapte le procédé précédemment conçu pour les foies de rats à des pièces et des résultats de foie humain dans un grand rendement des hépatocytes avec une viabilité de 77 ± 10%. Le principaldifférence de ce procédé est le processus de cannulization des vaisseaux sanguins. En outre, le procédé décrit ici peut également être appliquée à des foies provenant d&#39;autres espèces avec foie ou des vaisseaux sanguins de tailles comparables.

Configuration de perfusion L&#39;équipement requis pour la perfusion du foie doit être mis en place selon la figure 1. Viabilité et le rendement des hépatocytes humains isolés La viabilité moyenne des hépatocytes humains isolés était de 77 ± 10% et le rendement moyen des hépatocytes était de 13 ± 11 millions hépatocytes / g de foie, avec des valeurs exprimées en moyenne ± écart-type. Le nombre d&#39;isoleme...

Watch this Scientific Journal Video about Isolation of Human Hepatocytes by a Two-step Collagenase Perfusion Procedure at JoVE.com

Isolation of Human Hepatocytes by a Two-step Collagenase Perfusion Procedure

Une procédure en deux étapes de la collagénase de perfusion modifié pour l&#39;isolement d&#39;hépatocytes humains est décrit. Cette méthode peut également être appliquée à d&#39;autres foies de mammifères. Les hépatocytes isolés sont disponibles en haute rendement et la viabilité, les un modèle approprié pour la recherche scientifique dans des domaines tels que la régénération du foie, la pharmacocinétique et la toxicologie faire.

Isolement des hépatocytes humains par un deux-étape collagénase procédure de perfusion

The liver, an organ with an exceptional regeneration capacity, carries out a wide range of functions, such as detoxification, metabolism and homeostasis. ...

isolation-human-hepatocytes-two-step-collagenase-perfusion

Research

JoVE Journal

Biology

30.8K vues.  Grosshadern Hospital, Munich.  Une procédure en deux étapes de la collagénase de perfusion modifié pour l'isolement d'hépatocytes humains est décrit. Cette méthode peut également être appliquée à d'autres foies de mammifères. Les hépatocytes isolés sont disponibles en haute rendement et la viabilité, les un modèle approprié pour la recherche scientifique dans des domaines tels que la régénération du foie, la pharmacocinétique et la toxicologie faire. 

Vidéo: Isolation of Human Hepatocytes by a Two-step Collagenase Perfusion Procedure

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.

Dérivation des cellules souches embryonnaires humaines par 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 ...

Recherche

Biologie

Isolation of Rat Portal Fibroblasts by In situ Liver Perfusion

Liver fibrosis is defined by the excessive deposition of extracellular matrix by activated myofibroblasts. There are multiple precursors of hepatic myofibroblasts, including hepatic stellate cells, portal fibroblasts and bone marrow derived fibroblasts 1. Hepatic stellate cells have been the best studied, but portal fibroblasts are increasingly recognized as important contributors to the myofibroblast pool, particularly in biliary fibrosis 2. Portal fibroblasts undergo proliferation in response to biliary epithelial injury, potentially playing a key role in the early stages of biliary scarring 3-5. A method of isolating portal fibroblasts would allow in vitro study of this cell population and lead to greater understanding of the role portal fibroblasts play in biliary fibrosis.
Portal fibroblasts have been isolated using various techniques including outgrowth 6, 7 and liver perfusion with enzymatic digestion followed by size selection 8. The advantage of the digestion and size selection technique compared to the outgrowth technique is that cells can be studied without the necessity of passage in culture. Here, we describe a modified version of the original technique described by Kruglov and Dranoff 8 for isolation of portal fibroblasts from rat liver that results in a relatively pure population of primary cells.

Isolation of Rat Portal Fibroblasts by In situ Liver Perfusion

A technique for isolating portal fibroblasts from rat liver is described. Livers are perfused and digested in situ with collagenase, followed by ex vivo digestion of the liver slurry and size selection of cells. This method provides a pure population of portal fibroblasts without the need for passage in culture.

Isolement des fibroblastes de rat par portail<em&gt; In situ</emPerfusion du foie&gt;

Liver fibrosis is defined  by the excessive deposition of extracellular matrix by activated  myofibroblasts. There are multiple precursors of hepatic ...

Mouse Islet of Langerhans Isolation using a Combination of Purified Collagenase and Neutral Protease

The interrogation of beta cell gene expression and function in vitro has squarely shifted over the years from the study of rodent tumorigenic cell lines to the study of isolated rodent islets. Primary islets offer the distinct advantage that they more faithfully reflect the biology of intracellular signaling pathways and secretory responses. Whereas the method of islet isolation using tissue dissociating enzyme (TDE) preparations has been well established in many laboratories1-4, variations in the consistency of islet yield and quality from any given rodent strain limit the extent and feasibility of primary islet studies. These variations often occur as a result of the crude partially purified TDEs used in the islet isolation procedure; TDEs frequently exhibit lot-to-lot variations in activity and often require adjustments to the dose of enzyme used. A small number of reports have used purified TDEs for rodent cell isolations5, 6, but the practice is not widespread despite the routine use and advantages of purified TDEs for human islet isolations. In collaboration with VitaCyte, LLC (Indianapolis, IN), we developed a modified mouse islet isolation protocol based on that described by Gotoh7, 8, in which the TDEs are perfused directly into the pancreatic duct of mice, followed by crude tissue fractionation through a Histopaque gradient9, and isolation of purified islets. A significant difference in our protocol is the use of purified collagenase (CIzyme MA) and neutral protease (CIzyme BP) combination. The collagenase was characterized by the use of a6 fluorescence collagen degrading activity (CDA) assay that utilized fluorescently labeled soluble calf skin fibrils as substrate6. This substrate is more predictive of the kinetics of collagen degradation in the tissue matrix because it relies on native collagen as the substrate. The protease was characterized with a sensitive fluorescent kinetic assay10. Utilizing these improved assays along with more traditional biochemical analysis enable the TDE to be manufactured more consistently, leading to improved performance consistency between lots. The protocol described in here was optimized for maximal islet yield and optimal islet morphology using C57BL/6 mice. During the development of this protocol, several combinations of collagenase and neutral proteases were evaluated at different concentrations, and the final ratio of collagenase:neutral protease of 35:10 represents enzyme performance comparable to Sigma Type XI. Because significant variability in average islet yields from different strains of rats and mice have been reported, additional modifications of the TDE composition should be made to improve the yield and quality of islets recovered from different species and strains.

A detailed description of mouse islet isolation is described using the technique of in situ pancreatic ductal cannulation and perfusion of a combination of purified collagenase and neutral protease.

Souris îlot de Langerhans isolement à l&#39;aide d&#39;une combinaison de la collagénase purifiée et protéase neutre

The interrogation of beta cell gene expression and function in vitro has squarely shifted over the years from the study of rodent tumorigenic cell lines ...

GST-His purification: A Two-step Affinity Purification Protocol Yielding Full-length Purified Proteins

Key assays in enzymology for the biochemical characterization of proteins in vitro necessitate high concentrations of the purified protein of interest. Protein purification protocols should combine efficiency, simplicity and cost effectiveness1. Here, we describe the GST-His method as a new small-scale affinity purification system for recombinant proteins, based on a N-terminal Glutathione Sepharose Tag (GST)2,3 and a C-terminal 10xHis tag4, which are both fused to the protein of interest. The latter construct is used to generate baculoviruses, for infection of Sf9 infected cells for protein expression5. GST is a rather long tag (29 kDa) which serves to ensure purification efficiency. However, it might influence physiological properties of the protein. Hence, it is subsequently cleaved off the protein using the PreScission enzyme6. In order to ensure maximum purity and to remove the cleaved GST, we added a second affinity purification step based on the comparatively small His-Tag. Importantly, our technique is based on two different tags flanking the two ends of the protein, which is an efficient tool to remove degraded proteins and, therefore, enriches full-length proteins. The method presented here does not require an expensive instrumental setup, such as FPLC. Additionally, we incorporated MgCl2 and ATP washes to remove heat shock protein impurities and nuclease treatment to abolish contaminating nucleic acids. In summary, the combination of two different tags flanking the N- and the C-terminal and the capability to cleave off one of the tags, guaranties the recovery of a highly purified and full-length protein of interest.

In the present protocol, we demonstrate a highly efficient and cost-effective small-scale protein purification method, which allows purification of recombinant proteins by uniquely combining a cleavable GST-tag and a small His-tag.

TPS-Sa purification: A deux pas d&#39;affinité Protocole Purification Cédant longs protéines purifiées

Key assays in enzymology for the biochemical characterization of proteins in vitro necessitate high concentrations of the purified protein of interest. ...

Examination of Drosophila Larval Tracheal Terminal Cells by Light Microscopy

Cell shape is critical for cell function. However, despite the importance of cell morphology, little is known about how individual cells generate specific shapes. Drosophila tracheal terminal cells have become a powerful genetic model to identify and elucidate the roles of genes required for generating cellular morphologies. Terminal cells are a component of a branched tubular network, the tracheal system that functions to supply oxygen to internal tissues. Terminal cells are an excellent model for investigating questions of cell shape as they possess two distinct cellular architectures. First, terminal cells have an elaborate branched morphology, similar to complex neurons; second, terminal cell branches are formed as thin tubes and contain a membrane-bound intracellular lumen. Quantitative analysis of terminal cell branch number, branch organization and individual branch shape, can be used to provide information about the role of specific genetic mechanisms in the making of a branched cell. Analysis of tube formation in these cells can reveal conserved mechanisms of tubulogenesis common to other tubular networks, such as the vertebrate vasculature. Here we describe techniques that can be used to rapidly fix, image, and analyze both branching patterns and tube formation in terminal cells within Drosophila larvae. These techniques can be used to analyze terminal cells in wild-type and mutant animals, or genetic mosaics. Because of the high efficiency of this protocol, it is also well suited for genetic, RNAi-based, or drug screens in the Drosophila tracheal system.

Examination of Drosophila Larval Tracheal Terminal Cells by Light Microscopy

Here, we present a method for light microscopy analysis of tracheal terminal cells in Drosophila larvae. This method allows for quick examination of branch and lumen morphology in whole animals and would be useful for analysis of individual mutants or screens for mutations affecting terminal cell development.

Examen de<em&gt; Drosophila</em&gt; Larvaires cellules terminales trachéales par microscopie optique

Cell shape is critical for cell function. However, despite the importance of cell morphology, little is known about how individual cells generate specific ...

Protocol for Isolation of Primary Human Hepatocytes and Corresponding Major Populations of Non-parenchymal Liver Cells

Beside parenchymal hepatocytes, the liver consists of non-parenchymal cells (NPC) namely Kupffer cells (KC), liver endothelial cells (LEC) and hepatic Stellate cells (HSC). Two-dimensional (2D) culture of primary human hepatocyte (PHH) is still considered as the &#34;gold standard&#34; for in vitro testing of drug metabolism and hepatotoxicity. It is well-known that the 2D monoculture of PHH suffers from dedifferentiation and loss of function. Recently it was shown that hepatic NPC play a central role in liver (patho-) physiology and the maintenance of PHH functions. Current research focuses on the reconstruction of in vivo tissue architecture by 3D- and co-culture models to overcome the limitations of 2D monocultures. Previously we published a method to isolate human liver cells and investigated the suitability of these cells for their use in cell cultures in Experimental Biology and Medicine1. Based on the broad interest in this technique the aim of this article was to provide a more detailed protocol for the liver cell isolation process including a video, which will allow an easy reproduction of this technique.
Human liver cells were isolated from human liver tissue samples of surgical interventions by a two-step EGTA/collagenase P perfusion technique. PHH were separated from the NPC by an initial centrifugation at 50 x g. Density gradient centrifugation steps were used for removal of dead cells. Individual liver cell populations were isolated from the enriched NPC fraction using specific cell properties and cell sorting procedures. Beside the PHH isolation we were able to separate KC, LEC and HSC for further cultivation.
Taken together, the presented protocol allows the isolation of PHH and NPC in high quality and quantity from one donor tissue sample. The access to purified liver cell populations could allow the creation of in vivo like human liver models.

A technique to isolate human hepatocytes and non-parenchymal liver cells from the same donor is described. The different liver cell types build the basis for functional liver models and tissue engineering. This new method aims to isolate liver cells in a high yield and viability.

Protocole pour l&#39;isolement des hépatocytes humains primaires et correspondant Principales populations de cellules hépatiques non parenchymateuses

Beside parenchymal hepatocytes, the liver consists of non-parenchymal cells (NPC) namely Kupffer cells (KC), liver endothelial cells (LEC) and hepatic ...

Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing

The human gut is colonized by trillions of bacteria that support physiologic functions such as food metabolism, energy harvesting, and regulation of the immune system. Perturbation of the healthy gut microbiome has been suggested to play a role in the development of inflammatory diseases, including multiple sclerosis (MS). Environmental and genetic factors can influence the composition of the microbiome; therefore, identification of microbial communities linked with a disease phenotype has become the first step towards defining the microbiome&#8217;s role in health and disease. Use of 16S rRNA metagenomic sequencing for profiling bacterial community has helped in advancing microbiome research. Despite its wide use, there is no uniform protocol for 16S rRNA-based taxonomic profiling analysis. Another limitation is the low resolution of taxonomic assignment due to technical difficulties such as smaller sequencing reads, as well as use of only forward (R1) reads in the final analysis due to low quality of reverse (R2) reads. There is need for a simplified method with high resolution to characterize bacterial diversity in a given biospecimen. Advancements in sequencing technology with the ability to sequence longer reads at high resolution have helped to overcome some of these challenges. Present sequencing technology combined with a publicly available metagenomic analysis pipeline such as R-based Divisive Amplicon Denoising Algorithm-2 (DADA2) has helped advance microbial profiling at high resolution, as DADA2 can assign sequence at the genus and species levels. Described here is a guide for performing bacterial profiling using two-step amplification of the V3-V4 region of the 16S rRNA gene, followed by analysis using freely available analysis tools (i.e., DADA2, Phyloseq, and METAGENassist). It is believed that this simple and complete workflow will serve as an excellent tool for researchers interested in performing microbiome profiling studies.

Described here is a simplified standard operating procedure for microbiome profiling using 16S rRNA metagenomic sequencing and analysis using freely available tools. This protocol will help researchers who are new to the microbiome field as well as those requiring updates on methods to achieve bacterial profiling at a higher resolution.

Analyse du microbiote à l'aide de PCR en deux étapes et de la prochaine génération 16S rRNA Gene Sequencing

The human gut is colonized by trillions of bacteria that support physiologic functions such as food metabolism, energy harvesting, and regulation of the ...

A Two-Step Strategy that Combines Epigenetic Modification and Biomechanical Cues to Generate Mammalian Pluripotent Cells

Cell phenotype can be reversed or modified with different methods, with advantages and limitations that are specific for each technique. Here we describe a new strategy that combines the use of chemical epigenetic erasing with mechanosensing-related cues, to generate mammalian pluripotent cells. Two main steps are required. In the first step, adult mature (terminally differentiated) cells are exposed to the epigenetic eraser 5-aza-cytidine to drive them into a pluripotent state. This part of the protocol was developed, based on the increasing understanding of the epigenetic mechanisms controlling cell fate and differentiation, and involves the use of the epigenetic modifier to erase cell differentiated state and then drive into a transient high plasticity window.
In the second step, erased cells are encapsulated in polytetrafluoroethylene (PTFE) micro-bioreactors, also known as Liquid Marbles, to promote 3D cell rearrangement to extend and stably maintain the acquired high plasticity. PTFE is a non-reactive hydrophobic synthetic compound and its use permits the creation of a cellular microenvironment, which cannot be achieved in traditional 2D culture systems. This system encourages and boosts the maintenance of pluripotency though bio-mechanosensing-related cues.
The technical procedures described here are simple strategies to allow for the induction and maintenance of a high plasticity state in adult somatic cells. The protocol allowed the derivation of high plasticity cells in all mammalian species tested. Since it does not involve the use of gene transfection and is free of viral vectors, it may represent a notable technological advance for translational medicine applications. Furthermore, the micro-bioreactor system provides a notable advancement in stem cell organoid technology by in vitro re-creating a specific micro-environment that allows for the long-term culture of high plasticity cells, namely as ESCs, iPSCs, epigenetically erased cells and MSCs.

We here present a method that combines the use of chemical epigenetic erasing with mechanosensing-related cues to efficiently generate mammalian pluripotent cells, without the need of gene transfection or retroviral vectors. This strategy is, therefore, promising for translational medicine and represents a notable advancement in stem cell organoid technology.

Une stratégie en deux étapes qui combine la modification épigénétique et les indices biomécaniques pour générer des cellules pluripotentes de mammifères

Cell phenotype can be reversed or modified with different methods, with advantages and limitations that are specific for each technique. Here we describe ...

Isolation of Primary Rat Hepatocytes with Multiparameter Perfusion Control

Primary hepatocytes are widely used in basic research on liver diseases and for toxicity testing in vitro. The two-step collagenase perfusion procedure for primary hepatocyte isolation is technically challenging, especially in portal vein cannulation. The procedure is also prone to occasional contamination and variations in perfusion conditions due to difficulties in the assembly, optimization, or maintenance of the perfusion setup. Here, a detailed protocol for an improved two-step collagenase perfusion procedure with multiparameter perfusion control is presented. Primary rat hepatocytes were successfully and reliably isolated by taking the necessary technical precautions at critical steps of the procedure, and by reducing the operational difficulty and mitigating the variability of perfusion parameters through the adoption of a special intravenous catheter, standardized sterile disposable tubing, temperature control, and real-time monitoring and alarm system. The isolated primary rat hepatocytes consistently exhibit high cell viability (85%-95%), yield (2-5 x 108 cells per 200-300 g rat) and functionality (albumin, urea and CYP activity). The procedure was complemented by an integrated perfusion system, which is compact enough to be set up in the laminar flow hood to ensure aseptic operation.

This protocol details the use of a special intravenous catheter, standardized sterile disposable tubing, temperature control complemented by real-time monitoring, and an alarm system for two-step collagenase perfusion procedure to improve the consistency in the viability, yield, and functionality of isolated primary rat hepatocytes.

Isolement des hépatocytes primaires de rat avec contrôle de perfusion multiparamétrique

Primary hepatocytes are widely used in basic research on liver diseases and for toxicity testing in vitro. The two-step collagenase perfusion procedure ...

Amélioration de la quantification des protéines à l’aide de l’isolement mitochondrial en deux étapes

Two-Step Tag-Free Isolation of Mitochondria for Improved Protein Discovery and Quantification

Most physiological and disease processes, from central metabolism to immune response to neurodegeneration, involve mitochondria. The mitochondrial proteome is composed of more than 1,000 proteins, and the abundance of each can vary dynamically in response to external stimuli or during disease progression. Here, we describe a protocol for isolating high-quality mitochondria from primary cells and tissues. The two-step procedure comprises (1) mechanical homogenization and differential centrifugation to isolate crude mitochondria, and (2) tag-free immune capture of mitochondria to isolate pure organelles and eliminate contaminants. Mitochondrial proteins from each purification stage are analyzed by quantitative mass spectrometry, and enrichment yields are calculated, allowing the discovery of novel mitochondrial proteins by subtractive proteomics. Our protocol provides a sensitive and comprehensive approach to studying mitochondrial content in cell lines, primary cells, and tissues.

Pleins feux sur l’auteur : Isolement des mitochondries en deux étapes sans marquage pour une meilleure découverte et quantification des protéines  

We present a two-step protocol for high-quality mitochondria isolation that is compatible with protein discovery and quantification at a proteome scale. Our protocol does not require genetic engineering and is thus suitable for studying mitochondria from any primary cells and tissues.