We would like to thank Jia Li Liu for their support in creation of Figure 1. This study was supported by the German Federal Ministry of Education and Research (BMBF) project Virtual Liver: 0315741.

Note: All cells were isolated from resected non-tumorous human liver tissue, which remained after partial liver resection with primary or secondary liver tumors. Informed consent of the patients was obtained according to the ethical guidelines of the Charit&#233; - Universit&#228;tsmedizin Berlin.
1. Preparation of Materials and Solutions
<ol>
	<li>Sterilize all instruments and the materials in advance to avoid bacterial contamination during the isolation process.</li>
	<li>Prepare the solut...

<ol>
	<li>Pfeiffer, 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=Isolation,+characterization,+and+cultivation+of+human+hepatocytes+and+non-parenchymal+liver+cells.">Isolation, characterization, and cultivation of human hepatocytes and non-parenchymal liver cells.</a> Exp Biol Med. , (2014).</li><li>Si-Tayeb, K., Lemaigre, F. P., Duncan, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organogenesis+and+development+of+the+liver.">Organogenesis and development of the liver.</a> Dev Cell. 18 (2), 175-189 (2010).</li><li>Alpini, G., Phillips, J. O., Vroman, B., LaRusso, N. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+the+isolation+of+liver+cells.">Recent advances in the isolation of liver cells.</a> Hepatology. 20 (2), 494-514 (1994).</li><li>Godoy, 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=Recent+advances+in+2D+and+3D+in+vitro+systems+using+primary+hepatocytes,+alternative+hepatocyte+sources+and+non-parenchymal+liver+cells+and+their+use+in+investigating+mechanisms+of+hepatotoxicity,+cell+signaling+and+ADME.">Recent advances in 2D and 3D in vitro systems using primary hepatocytes, alternative hepatocyte sources and non-parenchymal liver cells and their use in investigating mechanisms of hepatotoxicity, cell signaling and ADME.</a> Arch Toxicol. 87 (8), 1315-1530 (2013).</li><li>G&#243;mez-Lech&#243;n, M. J., Castell, J. V., Donato, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hepatocytes--the+choice+to+investigate+drug+metabolism+and+toxicity+in+man:+in+vitro+variability+as+a+reflection+of+in+vivo.">Hepatocytes--the choice to investigate drug metabolism and toxicity in man: in vitro variability as a reflection of in vivo.</a> Chem Biol Interact. 168 (1), 30-50 (2007).</li><li>Ginai, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+bioreactors+as+in+vitro+models+in+pharmaceutical+research.">The use of bioreactors as in vitro models in pharmaceutical research.</a> Drug Discov Today. 18 (19-20), 922-935 (2013).</li><li>Schyschka, L., 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=Hepatic+3D+cultures+but+not+2D+cultures+preserve+specific+transporter+activity+for+acetaminophen-induced+hepatotoxicity.">Hepatic 3D cultures but not 2D cultures preserve specific transporter activity for acetaminophen-induced hepatotoxicity.</a> Arch Toxicol. 87 (8), 1581-1593 (2013).</li><li>Kostadinova, R., 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=A+long-term+three+dimensional+liver+co-culture+system+for+improved+prediction+of+clinically+relevant+drug-induced+hepatotoxicity.">A long-term three dimensional liver co-culture system for improved prediction of clinically relevant drug-induced hepatotoxicity.</a> Toxicol Appl Pharmacol. 268 (1), 1-16 (2013).</li><li>Messner, S., Agarkova, I., Moritz, W., Kelm, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multi-cell+type+human+liver+microtissues+for+hepatotoxicity+testing.">Multi-cell type human liver microtissues for hepatotoxicity testing.</a> Arch Toxicol. 87 (1), 209-213 (2013).</li><li>Nussler, A. K., Nussler, N. C., Merk, V., Brulport, M., Schormann, W., Yao, P., Hengstler, J. G., Santin, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Holy+Grail+of+Hepatocyte+Culturing+and+Therapeutic+Use.">The Holy Grail of Hepatocyte Culturing and Therapeutic Use.</a> Strategies in Regenerative Medicine. , 1-38 (2009).</li><li>Friedman, S. L., Roll, F. J. <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+lipocytes,+Kupffer+cells,+and+sinusoidal+endothelial+cells+by+density+gradient+centrifugation+with+Stractan.">Isolation and culture of hepatic lipocytes, Kupffer cells, and sinusoidal endothelial cells by density gradient centrifugation with Stractan.</a> Anal Biochem. 161 (1), 207-218 (1987).</li><li>Knook, D. L., Blansjaar, N., Sleyster, E. C. <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+characterization+of+Kupffer+and+endothelial+cells+from+the+rat+liver.">Isolation and characterization of Kupffer and endothelial cells from the rat liver.</a> Exp Cell Res. 109 (2), 317-329 (1977).</li><li>Alabraba, E. B., 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=A+new+approach+to+isolation+and+culture+of+human+Kupffer+cells.">A new approach to isolation and culture of human Kupffer cells.</a> J Immunol Methods. 326 (1-2), 139-144 (2007).</li><li>Friedman, S. L., 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=Isolated+hepatic+lipocytes+and+Kupffer+cells+from+normal+human+liver:+morphological+and+functional+characteristics+in+primary+culture.">Isolated hepatic lipocytes and Kupffer cells from normal human liver: morphological and functional characteristics in primary culture.</a> Hepatology. 15 (2), 234-243 (1992).</li><li>Lalor, P. F., Lai, W. K., Curbishley, S. M., Shetty, S., Adams, D. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+hepatic+sinusoidal+endothelial+cells+can+be+distinguished+by+expression+of+phenotypic+markers+related+to+their+specialised+functions+in+vivo.">Human hepatic sinusoidal endothelial cells can be distinguished by expression of phenotypic markers related to their specialised functions in vivo.</a> World J Gastroenterol. 12 (34), 5429-5439 (2006).</li><li>Lee, S. M., Schelcher, C., Demmel, M., Hauner, M., Thasler, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+human+hepatocytes+by+a+two-step+collagenase+perfusion+procedure.">Isolation of human hepatocytes by a two-step collagenase perfusion procedure.</a> J Vis Exp. (79), (2013).</li><li>Rajan, N., Habermehl, J., Cot&#233;, M. F., Doillon, C. J., Mantovani, D. <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+ready-to-use,+storable+and+reconstituted+type+I+collagen+from+rat+tail+tendon+for+tissue+engineering+applications.">Preparation of ready-to-use, storable and reconstituted type I collagen from rat tail tendon for tissue engineering applications.</a> Nat Protoc. 1 (6), 2753-2758 (2006).</li><li>Chang, W., 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=Isolation+and+culture+of+hepatic+stellate+cells+from+mouse+liver.">Isolation and culture of hepatic stellate cells from mouse liver.</a> Acta Biochim Biophys Sin (Shanghai). 46 (4), 291-298 (2014).</li><li>Zeng, W. Q., 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=A+new+method+to+isolate+and+culture+rat+kupffer+cells.">A new method to isolate and culture rat kupffer cells.</a> PLoS One. 8 (8), e70832 (2013).</li><li>Tokairin, T., 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=A+highly+specific+isolation+of+rat+sinusoidal+endothelial+cells+by+the+immunomagnetic+bead+method+using+SE-1+monoclonal+antibody.">A highly specific isolation of rat sinusoidal endothelial cells by the immunomagnetic bead method using SE-1 monoclonal antibody.</a> J Hepatol. 36 (6), 725-733 (2002).</li><li>Damm, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+parenchymal+and+non-parenchymal+liver+cell+isolation,+culture+and+characterization.">Human parenchymal and non-parenchymal liver cell isolation, culture and characterization.</a> Hepatology International. 7, 915-958 (2013).</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=Isolation+of+human+hepatocytes+from+livers+rejected+for+liver+transplantation+on+a+national+basis:+results+of+a+2-year+experience.">Isolation of human hepatocytes from livers rejected for liver transplantation on a national basis: results of a 2-year experience.</a> Liver Transpl. 9 (5), 506-512 (2003).</li><li>Shen, L., Hillebrand, A., Wang, D. Q., Liu, 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+primary+culture+of+rat+hepatic+cells.">Isolation and primary culture of rat hepatic cells.</a> J Vis Exp. (64), (2012).</li><li>Gerlach, J. C., 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=Large-scale+isolation+of+sinusoidal+endothelial+cells+from+pig+and+human+liver.">Large-scale isolation of sinusoidal endothelial cells from pig and human liver.</a> J Surg Res. 100 (1), 39-45 (2001).</li></ol>

The published protocol describes a technique to isolate pure PHH and NPC, namely KC, HSC and LEC, simultaneously in high quality and purity from the same sample of human liver tissue. The majority of publications dealing with liver cell isolations cover only one of those cell populations18-20 and isolation procedures performed with human tissue are rare (reviewed by Damm et al.)21. Adaption of methods established with animal tissue (e.g., rat liver) to human liver revealed several ...

Human liver tissue is highly complex and consists of two different cell entities, parenchymal cells and non-parenchymal cells (NPC). Parenchymal liver cells include hepatocytes and cholangiocytes. Hepatocytes represent 60 to 70% of total liver cells and account for most of the metabolic liver functions,&#160;e.g., bile acid and complement factor synthesis, biotransformation and energy metabolism2,3.
The smaller NPC fraction constitutes 30-40% of total liver cells. NPC include different cell populations, namely Kupffer cells (KC), liver endothelial cells (LEC) and the hepatic stellate cells (HSC). This heterogenic cell fraction plays a central role in physiological processes of the liver. Additionally, NPC participate in mediating acute liver damage,&#160;e.g., drug-induced liver injury (DILI) as well as in chronic liver injuries, such as cirrhosis4.
In recent years, human liver cells have become more and more essential in research and development of drug testing, drug development and identification of new biochemical pathways in liver diseases. For in vitro testing PHH monocultures are still considered as the &#34;gold standard&#34;5. The main limitation of current homotypic liver models is dedifferentiation and loss of function of the hepatocytes within a few days4. The establishment of 3-dimensional (3D) culture techniques has shown that these limitations can be compensated4,6. However, even modern 3D culture techniques are not able to display all hepatotoxic modes of actions7. Missing NPC populations in the existing in vitro models are discussed as a possible reason for this discrepancy to the in vivo situation. It has been shown that the cell-cell communication between the different liver cell populations plays a central role in physiological homeostasis but also in pathophysiologic processes8. Therefore the scientific attention focuses more and more on NPC and their cell-cell interactions. Their purposeful use in co-culture and tissue engineered systems could be a solution for the high demand of in vitro liver models8,9 which are as close to the in vivo situation as possible.
Currently the main challenge is the development of a standardized human liver co-culture model, which contains clearly defined portions of PHH and NPC. In consequence, isolation techniques for the very heterogenic liver cells are needed and those have to be optimized to gain pure cell populations. While standardized protocols for PHH isolation exist10, the standardized isolation of human NPC is still under development. Most published NPC isolation protocols are based on experiments with non-human cells11,12. Only a few publications describe the isolation process of human NPC and most cover only methods for the isolation of a single cell type11-16. The most important cell characteristics that have been harnessed for cell separation are size, density, attachment behavior, and the expression of surface proteins. On the basis of these characteristics we developed a simplified protocol to isolate PHH, KC, LEC and HSC, which was published previously in Experimental Biology and Medicine1. Because of 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 reproducing the technique more easily. The protocol also includes quality control methods for evaluation of yield and viability as well as for identification and purity evaluation using specific immunostainings.

<table border="0" cellpadding="0" cellspacing="0" width="886">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:268px;">General Equipment</td>
			<td style="width:147px;"></td>
			<td style="width:293px;"></td>
			<td style="width:179px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">PIPETBOY</td>
			<td>Eppendorf</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pipettes</td>
			<td>Eppendorf</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">microscope</td>
			<td>Carl Zeiss</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">microscope</td>
			<td>Olympus</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CO2-incubator</td>
			<td>Binder</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Lamin Air</td>
			<td>Heraeus</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Centrifuge Varifuge 3.0R</td>
			<td>Heraeus</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Urine Beaker</td>
			<td>Sarstedt</td>
			<td>2041101</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">perfusor syringe 50 ml</td>
			<td>B.Braun</td>
			<td>12F0482022</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Bottle Top Filter</td>
			<td>Nalgene</td>
			<td>1058787</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Falcon 50 ml Polypropylene Conical Tube</td>
			<td>BD Biosciences</td>
			<td>352070</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Falcon 15 ml Polypropylene Conical Tube</td>
			<td>BD Biosciences</td>
			<td>352096</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tissue Culture plate</td>
			<td>BD Biosciences</td>
			<td>533047</td>
			<td>24 well</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">serological pipettes</td>
			<td>BD Biosciences</td>
			<td>357525, 357551, 357543</td>
			<td>25 ml, 10 ml, 5 ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pipette tips</td>
			<td>SARSTEDT</td>
			<td>0220/2278014, 0005/2242011, 0817/2222011</td>
			<td>100 &#181;l, 200 &#181;l, 1000 &#181;l</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Isolation Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">water bath</td>
			<td>Lauda</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">peristaltic pump</td>
			<td>Carl Roth</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">circulation thermostat</td>
			<td>Lauda</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">pH meter</td>
			<td>Schott</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">fine scales</td>
			<td>Sartorius</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">stand</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">B&#252;chner funnel</td>
			<td>Haldenwanger</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">plastic funnel</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">silicone tube</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">cannulae with olive tips</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">glass dish</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">forceps</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">scalpel</td>
			<td>Feather</td>
			<td>12068760</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Neubauer counting chamber</td>
			<td>Optic Labor</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">cell lifter</td>
			<td>Costar</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Surgical Drape</td>
			<td>Charit&#233; Universit&#228;tsmedizin Berlin</td>
			<td>A2013027</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">compress</td>
			<td>Fuhrmann</td>
			<td>40013331</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">sterile surgical gloves</td>
			<td>Gammex PF</td>
			<td>1203441104</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Tissue glue</td>
			<td>B. Braun</td>
			<td>1050052</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">glass bottle</td>
			<td>VWR</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Collagenase P</td>
			<td>Roche</td>
			<td>13349524</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Percoll Separating Solution</td>
			<td>Biochrom</td>
			<td>L6145</td>
			<td>Density 1.124 g/ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hank&#8217;s BSS</td>
			<td>PAA</td>
			<td>H00911-3938</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Dulbecco&#8217;s PBS</td>
			<td>PAA</td>
			<td>H15 - 002</td>
			<td>without Mg/Ca</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ampuwa</td>
			<td>Plastipur&#160;</td>
			<td>13CKP151&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Albumin</td>
			<td>Sigma-Aldrich</td>
			<td>A7906</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">NaCl</td>
			<td>Merck</td>
			<td>1,064,041,000</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">KCl</td>
			<td>Merck</td>
			<td>49,361,000</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hepes Pufferan&#160;</td>
			<td>Roth</td>
			<td>133196836</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">EDTA</td>
			<td>Sigma</td>
			<td>E-5134</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Media Equipment&#160;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DMEM</td>
			<td>PAA</td>
			<td>E15-005</td>
			<td>Low Glucose (1 g/l) (without L-Glutamine)</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HEPES Buffer Solution 1M</td>
			<td>GIBCO</td>
			<td>1135546</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">L-Glutamine</td>
			<td>GIBCO</td>
			<td>25030-024</td>
			<td>200 mM</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">MEM NEAA</td>
			<td>GIBCO</td>
			<td>11140-035</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">penicillin/streptomycin</td>
			<td>GIBCO</td>
			<td>15140-122</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">RPMI 1640</td>
			<td>PAA</td>
			<td>E15 - 039</td>
			<td>without L-Glutamine</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sodium Pyruvate</td>
			<td>GIBCO</td>
			<td>1137663</td>
			<td>100 mM</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Trypan Blue Solution</td>
			<td>Sigma-Aldrich</td>
			<td>T8154</td>
			<td>0.4%</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">William&#8217;s E&#160;&#160;</td>
			<td>GIBCO</td>
			<td>32551-020</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">with GlutaMAX&#8482;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">EGTA</td>
			<td>Sigma-Aldrich</td>
			<td>03780-50G</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fortecortin</td>
			<td>Merck</td>
			<td>49367</td>
			<td>8 mg/2 ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Human-Insulin</td>
			<td>Lilly</td>
			<td>HI0210</td>
			<td>100 I.E./ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">N-Acetyl cysteine</td>
			<td>Sigma-Aldrich</td>
			<td>A9165-5G</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fetal calf serum (FCS)</td>
			<td>PAA</td>
			<td>A15-101</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Equipment for Immunostainings</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CD 68</td>
			<td>R&#38;D Systems, USA</td>
			<td></td>
			<td>monoclonal</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CK 19</td>
			<td>Santa Cruz</td>
			<td>D2309</td>
			<td>polyclonal</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">CK18</td>
			<td>Santa Cruz</td>
			<td>K2105</td>
			<td>monoclonal</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Vimentin</td>
			<td>Santa Cruz</td>
			<td></td>
			<td>monoclonal</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">GFAP</td>
			<td>Sigma Aldrich</td>
			<td></td>
			<td>monoclonal</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Triton X-100</td>
			<td>Sigma Aldrich</td>
			<td>23.472-9</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Goat anti-Mouse IgG1-PE</td>
			<td>Santa Cruz</td>
			<td>C0712</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Goat anti-rabbit IgG-FITC</td>
			<td>Santa Cruz</td>
			<td>L0412</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Methanol</td>
			<td>J.T.Baker</td>
			<td>1104509006</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Formaldehyde 4%</td>
			<td>Herbeta Arzneimittel</td>
			<td>200-001-8</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Bovine serum albumin (BSA)</td>
			<td>Sigma Aldrich</td>
			<td>A7906-100G</td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

The separation into a parenchymal and non-parenchymal fraction, using density gradient centrifugation as a clean-up procedure combined with the use of adherence properties and MACS leads to successful PHH and NPC isolation. PHH and NPC can be isolated in high quality and quantity. Figure 1 shows the representative setup of the equipment for liver perfusion and digestion. 10% FCS was added to the collagenase P containing Perfusion - Solution II to reduce proteolytic activi...

Watch this Scientific Journal Video about Protocol for Isolation of Primary Human Hepatocytes and Corresponding Major Populations of Non-parenchymal Liver Cells at JoVE.com

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

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.

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

This method can help to answer key questions in the field of hepatology and toxicology and offer us the opportunity for development of new in vitro co-culture and tissue engineered liver models. The advantage of this new technique is to isolate all liver cell populations from the same donor and the same small piece of liver tissue. To begin this procedure, weigh the freshly dissected liver tissue under stile conditions and place the liver tissue sample in the laminar airflow hood.Then clean the blood away from the surface of the tissue sample. Next, flush the cannulas using 1X perfusion solution one. Use the tissue glue to fix the olives of the cannulas in the larger blood vessels.Then, test the perfusion and check for leakages of the cannulas. Subsequently, close all blood vessels leaking clear 1X perfusion solution one with tissue glue. After that, place the cannulated liver tissue sample into the Buchner funnel.Then, set the flow rate of the peristaltic pump between 7.5 and 14.6 milliters per minute, depending on the number of cannulas used and the resistance of the liver tissue. Perfuse the tissue until the whole blood is flushed out for at least 20 minutes and for a maximum of 30 minutes. In some cases, it may be necessary to clamp one of the cannulas with plastic clamps or to increase the inner pressure of an area by pressing softly against the liver capsule with a spatula in order to optimize the perfusion.A complete color change from brownish red to light brown or light yellow indicates a good perfusion. Afterward, change the perfusion fluid to digestion solution containing collagenase P.Then, rearrange the setup for the digestion step. Subsequently, perform a circular flow of digestion solution for up to 15 minutes.Periodically stop the perfusion and check the degree of digestion. It is essential that the perfusion with digestion solution is stopped immediately when the liver tissue sample is digested sufficiently. Take the liver out of the device when ready and put it in a glass dish.Rinse the outside of the tissue sample with ice cold Stop Solution. Remove the cannulas from the liver tissue sample. Then, use a scalpel to open the liver tissue sample by incising the middle of the area where the cannulas were attached and be sure the Glisson's capsule stays intact.Rinse the inside of the tissue sample and then cover the whole tissue sample with Stop Solution. Next, shake the tissue gently in order to release the cells out of it. Then, collect the cell suspension and filter it through a gauze funnel into 10 50-milliliter plastic tubes.Add more Stop Solution to the liver tissue sample until a final volume of 500 milliliters is consumed. Afterward, centrifuge the cell suspension, collect the supernatant for NPC isolation later, and pool the cell pellets into 250-milliliters plastic tubes. Subsequently, wash the cell pellets with PBS.For that, centrifuge the cell suspension. Collect the supernatant, pool the pellets, and resuspend the pellet in hepatocyte incubation medium. Then, determine the cell number and viability in the resulting cell suspension using Trypan blue staining.To isolate the non-parenchymal liver cells, centrifuge the collected supernatant to eliminate the remaining erythrocytes and hepatocytes. Collect the supernatants and centrifuge them twice to gain the cell pellets for the sedimentation of HCS, LEC, partly KC, and the remaining KC.Next, re-suspend the pellets in HBSS. Then, prepare a 25%and a 50%density gradient by mixing the density-gradient solution and PBS for density-gradient centrifugation.Place the 25%density gradient solution carefully on top of the 50%density gradient solution layer. Subsequently, put the NPC suspension carefully and slowly on top of the 25%density gradient solution layer to achieve a clear separation of both layers. Centrifuge the cell suspension on the density gradient without break.The NPC are located in the interphase between the 25%and 50%density gradient layers. Aspirate the dead cells and cell debris from the uppermost layer and collect the interphase carefully. After dual centrifugation, perform a cell count for the KC and the MPC fraction.Then, centrifuge the NPC fraction with the previously described dual centrifugation step and resuspend the NPC in Kupffer Cell seeding medium. Seed the KC-containing fraction on the plastic cell culture vessels at a density of five times 10 to the 5th KC per square centimeter. Incubate the KC cultures for 20 minutes in a humidified incubator at 37 degrees Celsius 5%carbon dioxide.Primary KC should adhere on the cell culture plastics within a short period of time. Then, collect the supernatant containing the non-adhered NPC consisting mainly of LEC and HSC. To separate LEC from HSC, start with a centrifugation of the supernatant.Then, wash the pellet with PBS. After the second centrifugation, re-suspend the cells in stellate cell endothelial cell separation medium and perform a cell count for all remaining cells. Next, re-suspend 10 million cells in one milliliter of stellate cell endothelial cell separation medium.Then, add 20 microliters of blocking solution from the MAX kit and 20 microliters of the CD31 microbeads for immuno-labeling and incubate the resulting suspension for 15 minutes at four degrees Celsius temperature. Subsequently, separate LEC from HSC as described in the manufacturer's protocol for the magnetically activated cell sorting system max and collect the HSC fraction. Elute the magnetically retained CD31 positive LEC and suspend them in stellate cell endothelial cell culture medium.Here, these images show the different isolate liver cell populations directly after the isolation process in phase contrast microscopy view. This set of images presents the isolated and cultivated cells after 24 hours of cultivation. The immunofluorescence-based characterization of different cell fractions is shown here.PHH showed positive signals for the hepatocyte marker CK18 24 hours after isolation, KC were positive for the marker CD68 24 hours after isolation, LEC showed positive signals for vimentin 72 hours after isolation, and HSC were positive for GFAP 72 hours after isolation. While attempting this procedure, it's important to remember that a successful isolation depends on optimal digestion of the liver tissue sample. After watching this video, you should have a good understanding of how to control the digestion and how to perform the density gradient separation, which are the critical steps of this procedure.After its development, this technique paved the way for researchers in the field of medical research to explore hepatic functions and diseases in newly-created in vitro cell cultures and tissue engineered liver models.

protocol-for-isolation-primary-human-hepatocytes-corresponding-major

Research

JoVE Journal

Biology

36.4K visualizações.  Charité University Medicine Berlin. This method can help to answer key questions in the field of hepatology and toxicology and offer us the opportunity for development of new in vitro co-culture and tissue engineered liver models. The advantage of this new technique is to isolate all liver cell populations from the same donor and the same small piece of liver tissue. To begin this procedure, weigh the freshly dissected liver tissue under stile conditions and place the liver tissue sample in the laminar airflow hood.Then ...