This work was supported by the National Institutes of Health (Grant 5R01HD095512-02 to S.W.).

All procedures were approved by the Johns Hopkins Animal Care and Use Committee. C57BL/6 female mice (8-week old) were used in this study.
1. Preparation:
<ol>
	<li>Mix William&#39;s E Medium (GlutaMAX Supplement) with 10% FBS and 1% antibiotic-antimycotic solution to make the culture medium.</li>
	<li>Filter 25 mL of collagenase-dispase medium (e.g., Liver Digest Medium) through a 0.45 &#181;m syringe filter to remove particle debris.</li>
	<li>Warm 50 mL of double-distille...

<ol>
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Various primary hepatocyte isolation protocols have been developed. They also have been kept optimized and adapted based on different needs (Table 1). Isolation protocols are generally composed of two parts: perfusion (including enzyme digestion) and purification.
The perfusion can be performed with the entire liver in vivo2,20,21,22,</...

The liver serves as one of the most important organs in the vertebrate body due to the vital role it plays in numerous life-supporting functions like food digestion, blood circulation, and detoxification. Usage of mouse primary hepatocyte in vitro culture is increasingly popular in studies of carbohydrate metabolism and hepatic carcinoma. Therefore, it is important to develop a convenient method for mouse primary hepatocyte isolation while maintaining its innate physiological function. Due to its function as a hub of glucose metabolism, the liver is also central to glucose production and storage1. Experiments with primary hepatocytes in vitro are a must to most glucose metabolism studies. Therefore, for years, various research groups have developed protocols for mouse primary hepatocyte isolation.
The general procedure of mouse hepatocyte isolation is to first flush out blood in the liver with an isosmotic liquid such as phosphate-buffered saline (PBS) or Hanks&#39; Balanced Salt Solution (HBSS) and then use collagenase-containing solution to dissociate hepatocytes. These protocols share a general procedure but differ in reagents and steps based on different needs. However, preparing required reagents and performing isolation steps take time. In developing the present protocol, efficiency was set as a priority, with all reagents ready-to-use and available from the market, and as few steps as possible. The overall goal of this protocol is to provide a fast and labor-efficient method to isolate primary hepatocytes from mouse, without jeopardizing the isolated primary hepatocyte purity and viability.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1x PBS</td>
			<td>Gibco</td>
			<td>10010023</td>
			<td></td>
		</tr>
		<tr>
			<td>10x HBSS</td>
			<td>Gibco</td>
			<td>14065-056</td>
			<td></td>
		</tr>
		<tr>
			<td>12-well Plate</td>
			<td>FALCON</td>
			<td>353043</td>
			<td>Coating not required</td>
		</tr>
		<tr>
			<td>6-well Plate</td>
			<td>FALCON</td>
			<td>353046</td>
			<td>Coating not required</td>
		</tr>
		<tr>
			<td>anti-AKT</td>
			<td>Cell Signaling</td>
			<td>2920S</td>
			<td></td>
		</tr>
		<tr>
			<td>Antibiotic Antimycotic Solution (100x), Stabilized</td>
			<td>Sigma-Aldrich</td>
			<td>A5955</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-FOXO1</td>
			<td>Cell Signaling</td>
			<td>97635S</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-GAPDH</td>
			<td>Cell Signaling</td>
			<td>2118S</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-p-AKT (S473)</td>
			<td>Cell Signaling</td>
			<td>9271L</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-PEPCK</td>
			<td>Santa Cruz</td>
			<td>SC-166778</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-p-FOXO1 (S256)</td>
			<td>Cell Signaling</td>
			<td>84192S</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell Strainer, 70 &#181;m</td>
			<td>CELLTREAT</td>
			<td>229483</td>
			<td></td>
		</tr>
		<tr>
			<td>Closed IV Catheter, 24 Gauge 0.75 IN</td>
			<td>Becton Dickinson</td>
			<td>383511</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM, no glucose, no glutamine, no phenol red</td>
			<td>ThermoFisher Scientific</td>
			<td>A1443001</td>
			<td></td>
		</tr>
		<tr>
			<td>EnzyChrom Glucose Assay Kit</td>
			<td>BioAssay Systems</td>
			<td>EBGL-100</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Hyclone</td>
			<td>SH30071.03</td>
			<td></td>
		</tr>
		<tr>
			<td>Forskolin</td>
			<td>MilliporeSigma</td>
			<td>F3917-10MG</td>
			<td></td>
		</tr>
		<tr>
			<td>Glucagon</td>
			<td>Sigma-Aldrich</td>
			<td>G2044</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat Anti-mouse IgG Secondary Antibody</td>
			<td>LI-COR</td>
			<td>926-68070</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat Anti-rabbit IgG Secondary Antibody</td>
			<td>LI-COR</td>
			<td>926-32211</td>
			<td></td>
		</tr>
		<tr>
			<td>GraphPad Prism 8</td>
			<td>GraphPad Software</td>
			<td>NA</td>
			<td></td>
		</tr>
		<tr>
			<td>Hepatocyte Wash Medium</td>
			<td>Gibco</td>
			<td>17704-024</td>
			<td></td>
		</tr>
		<tr>
			<td>IBMX</td>
			<td>Cell Signaling</td>
			<td>13630S</td>
			<td></td>
		</tr>
		<tr>
			<td>Insulin</td>
			<td>Lilly</td>
			<td>NDC 0002-8215-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Ketamine HCL (100 mg/mL)</td>
			<td>Hospira Inc</td>
			<td>NDC 0409-2051-05</td>
			<td></td>
		</tr>
		<tr>
			<td>L-Glutamine</td>
			<td>Gibco</td>
			<td>25030081</td>
			<td></td>
		</tr>
		<tr>
			<td>Liver Digest MA2:D30edium</td>
			<td>Gibco</td>
			<td>17703-034</td>
			<td>Aliquot within tissue culture hood to 25 mL each in 50 mL tube, and keep in -20 &#176;C freezer</td>
		</tr>
		<tr>
			<td>Liver Perfusion Medium</td>
			<td>Gibco</td>
			<td>17701-038</td>
			<td></td>
		</tr>
		<tr>
			<td>Pen Strep</td>
			<td>Gibco</td>
			<td>15140122</td>
			<td></td>
		</tr>
		<tr>
			<td>Percoll</td>
			<td>GE Healthcare</td>
			<td>17-0891-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Peristaltic Pump</td>
			<td>Gilson</td>
			<td>Minipuls 2</td>
			<td>Capable of pumping at 4 mL/min</td>
		</tr>
		<tr>
			<td>Petri Dish</td>
			<td>Fisherbrand</td>
			<td>08-757-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Refrigerated Centrifuge</td>
			<td>Sorvall</td>
			<td>Legend RT</td>
			<td>Capable to centrifuge 50 mL tube at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Sodium L-Lactate</td>
			<td>Sigma-Aldrich</td>
			<td>L7022</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Pyruvate</td>
			<td>Gibco</td>
			<td>11360070</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe Filter, PVDF 0.45 &#181;m 30mm diameter</td>
			<td>CELLTREAT</td>
			<td>229745</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe, 0.5 mL</td>
			<td>Becton Dickinson</td>
			<td>329461</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe, 60 mL</td>
			<td>Becton Dickinson</td>
			<td>309653</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue Solution, 0.4%</td>
			<td>Gibco</td>
			<td>15250061</td>
			<td></td>
		</tr>
		<tr>
			<td>Tube, 15 mL</td>
			<td>Corning</td>
			<td>430052</td>
			<td></td>
		</tr>
		<tr>
			<td>Tube, 50 mL</td>
			<td>Corning</td>
			<td>430290</td>
			<td></td>
		</tr>
		<tr>
			<td>Water Bath Tank</td>
			<td>Corning</td>
			<td>CLS6783</td>
			<td>Or any water bath tank capable of heating up to 45 &#176;C</td>
		</tr>
		<tr>
			<td>William&#8217;s E Medium (GlutaMAX Supplement)</td>
			<td>Gibco</td>
			<td>32551020</td>
			<td></td>
		</tr>
		<tr>
			<td>Xylozine (100 mg/mL)</td>
			<td>Vetone Anased LA</td>
			<td>NDC13985-704-10</td>
			<td></td>
		</tr>
	</tbody>
</table>

an improved time- and labor- efficient protocol for mouse primary hepatocyte isolation

Primary hepatocytes are used extensively in liver in vitro research, especially in glucose metabolism studies. A base technique has been adapted based on different needs, like time, labor, cost, and primary hepatocyte usage, resulting in various primary hepatocyte isolation protocols. However, the numerous steps and time-consuming reagent preparations in primary hepatocyte isolation are major drawbacks for efficiency. After comparing different protocols for their pros and cons, the advantages of each were combined, and a rapid and efficient primary hepatocyte isolation protocol was formulated. Within only ~35 min, this protocol could yield as much, if not more, healthy primary hepatocytes as other protocols. Further, glucose metabolism experiments performed using the isolated primary hepatocytes validated the usefulness of this protocol in in vitro liver metabolism studies. We also extensively reviewed and analyzed the significance and purpose of each step in this study so that future researchers can further optimize this protocol based on needs.

In order to test the efficiency, the present primary hepatocyte isolation protocol was performed on 8-week old female C57BL/6 mice. The attachment and purity of isolated primary hepatocytes were tested. Primary hepatocyte isolation is used for a wide variety of experiments on liver physiology, such as hepatic drug effects and glucose metabolism, pharmaceutical biomarker activity2, insulin sensitivity, and glucose production. Therefore, the activities of the primary hepatocytes isolated with this p...

Watch this Scientific Journal Video about An Improved Time- and Labor- Efficient Protocol for Mouse Primary Hepatocyte Isolation at JoVE.com

An Improved Time- and Labor- Efficient Protocol for Mouse Primary Hepatocyte Isolation

Primary hepatocytes are a valuable tool to study liver response and metabolism in vitro. Utilizing commercially available reagents, an improved time- and labor-efficient protocol for mouse primary hepatocyte isolation was developed.

Primary hepatocytes are used extensively in liver in vitro research, especially in glucose metabolism studies. A base technique has been adapted based on ...

Mouse primary hepatocytes are important in liver studies. Especially for glucose metabolism, and hepatic drug testing. Time wise the isolation process can be time consuming and the energy costly.This protocol can provide an efficient way to isolate mouse primary hepatocytes. It is time and labor friendly. Requiring very few steps with all regions commercially available.Begin by using the peristaltic pump to start pumping warmed up double distilled water at a speed of 4 mL per minute, for five minutes. Then change the pumping tube from water to warmed up perfusion medium. Monitoring the air bubble between the water and perfusion medium.Will help track the flow of the perfusion medium through the system. Next disinfect the abdomen of an anesthetized eight week old C57 black 6J female mouse with 70%ethanol. And using a scissor, cut open the abdomen to expose the liver, portal vein and inferior vena cava.Then stop the peristaltic pump. After ensuring that the pumping tube contains perfusion medium and not water. Insert a 24 gauge catheter into the inferior vena cava.Switch the pump back on and cut the portal vein open. While the perfusion medium is being pumped, press the portal vein every minute to let the liquid reach every corner of the liver. Continue pumping for approximately three to five minutes or until the flushed out liquid is clear.Next change the pumping tube from the perfusion medium to the collagenase dispase medium. And press the portal vein every minute to let the liquid reach every corner of the liver. Continue pumping until all 25 mL of the collagenase dispase medium are depleted.Next isolate the whole liver without the gallbladder. And placed it in 30 mL of wash medium in a Petri dish on ice. Using forceps tear the liver into pieces to release primary hepatocytes into the solution.At this stage, the wash medium turns into a cloudy solution containing released primary hepatocytes and small liver pieces. Filter this cloudy solution through a 70 micron cell strainer, into 20 mL of 1X per call HBSS in a 50 mL tube on ice. And mix the solution by inverting the tube 20 times.Next centrifuge the solution. Then in the tissue culture hood, aspirate the supernatant. And wash the pellet with 30 mL of cold wash medium.Pellet the cells once again with centrifugation. Remove the supernatant, and re-suspend the pellet in 25 mL of culture medium. Count the cells and plate them on desired culture plates.According to the experimental design. After plating, isolated primary hepatocytes were firmly attached by one hour and fully expanded after 12 hours. In the isolated hepatocytes, mRNA levels of hepatocyte markers, such as transthyretin, CD95, ASGR1, and ASGR2 were significantly increased compared to the whole liver.In contrast the presence of immune cells, stellate cells, and endothelial cells was lower. As evidenced by a sharp decrease in CD45, collagen type 1 alpha 1, and endothelial cell 2 kinase 2 mRNA levels. Suggesting that this protocol can greatly reduce interference from other hepatic cells.After plating ASGR1 and ASGR2 levels decreased with time, but remain comparable to the whole liver until the 12 hour time point. Especially for ASGR1. The expression level of membrane bound CD81 was consistent for up to 48 hours.In comparison, toll-like receptor 4 expression generally increased and became higher than in vivo levels after 48 hours. Insulin sensitivity assays demonstrated that insulin significantly promoted phosphorylation of both AKT at serine 473. And forkhead box 01 at serine 256, in the hepatocytes.Indicating the sensitivity of primary hepatocytes to insulin. Phosphoenolpyruvate carboxykinase protein levels significantly increased after glucagon treatment. Suggesting that the glucose production pathway was activated.This activation was further confirmed by increased glucose production. And with other glucose production stimulators like Forskolin+IBMX. This protocol can save both time and energy for studies using mouse primary hepatocytes.Following this protocol, related experiments such as the hypothetical glucose metabolism and pharmaceutical biomarker assays can be carried out.

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8.6K vues.  Johns Hopkins University School of Medicine. Les hépatocytes primaires de souris sont importants dans les études sur le foie. Surtout pour le métabolisme du glucose et les tests de drogues hépatiques. En termes de temps, le processus d’isolement peut prendre beaucoup de temps et coûter de l’énergie.Ce protocole peut fournir un moyen efficace d’isoler les hépatocytes primaires de souris. C’est favorable au temps et au travail. Nécessitant très peu d’étapes avec toutes les régions disponibles dans le commerce.

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Neutrophil Isolation Protocol

Neutrophil polymorphonuclear granulocytes (PMN) are the most abundant leukocytes in humans and among the first cells to arrive on the site of inflammatory immune response. Due to their key role in inflammation, neutrophil functions such as locomotion, cytokine production, phagocytosis, and tumor cell combat are extensively studied. To characterize the specific functions of neutrophils, a clean, fast, and reliable method of separating them from other blood cells is desirable for in vitro studies, especially since neutrophils are short-lived and should be used within 2-4 hours of collection. Here, we demonstrate a standard density gradient separation method to isolate human neutrophils from whole blood using commercially available separation media that is a mixture of sodium metrizoate and Dextran 500. The procedure consists of layering whole blood over the density gradient medium, centrifugation, separation of neutrophil layer, and lysis of residual erythrocytes. Cells are then washed, counted, and resuspended in buffer to desired concentration. When performed correctly, this method has been shown to yield samples of >95% neutrophils with >95% viability.

Neutrophils are among the first cells to arrive on the site of inflammatory immune response, and their functions and mechanisms have been studied extensively in vitro. We demonstrate a standard density gradient separation method to isolate human neutrophils from whole blood using commercially available separation media.

Neutrophil polymorphonuclear granulocytes (PMN) are the most abundant leukocytes in humans and among the first cells to arrive on the site of inflammatory ...

An Improved Method of RNA Isolation from Loblolly Pine (P. taeda L.) and Other Conifer Species

Tissues isolated from conifer species, particularly those belonging to the Pinaceae family, such as loblolly pine (Pinus taeda L.), contain high concentrations of phenolic compounds and polysaccharides that interfere with RNA purification. Isolation of high-quality RNA from these species requires rigorous tissue collection procedures in the field and the employment of an RNA isolation protocol comprised of multiple organic extraction steps in order to isolate RNA of sufficient quality for microarray and other genomic analyses. The isolation of high-quality RNA from field-collected loblolly pine samples can be challenging, but several modifications to standard tissue and RNA isolation procedures greatly improve results. The extent of general RNA degradation increases if samples are not properly collected and transported from the field, especially during large-scale harvests. Total RNA yields can be increased significantly by pulverizing samples in a liquid nitrogen freezer mill prior to RNA isolation, especially when samples come from woody tissues. This is primarily due to the presence of oxidizing agents, such as phenolic compounds, and polysaccharides that are both present at high levels in extracts from the woody tissues of most conifer species. If not removed, these contaminants can carry over leading to problems, such as RNA degradation, that result in low yields and a poor quality RNA sample. Carryover of phenolic compounds, as well as polysaccharides, can also reduce or even completely eliminate the activity of reverse transcriptase or other polymerases commonly used for cDNA synthesis. In particular, RNA destined to be used as template for double-stranded cDNA synthesis in the generation of cDNA libraries, single-stranded cDNA synthesis for PCR or qPCR's, or for the synthesis of microarray target materials must be of the highest quality if researchers expect to obtain optimal results. RNA isolation techniques commonly employed for many other plant species are often insufficient in their ability to remove these contaminants from conifer samples and thus do not yield total RNA samples suitable for downstream manipulations. In this video we demonstrate methods for field collection of conifer tissues, beginning with the felling of a forty year-old tree, to the harvesting of phloem, secondary xylem, and reaction wood xylem. We also demonstrate an RNA isolation protocol that has consistently yielded high-quality RNA for subsequent enzymatic manipulations.

An Improved Method of RNA Isolation from Loblolly Pine P. taeda L. and Other Conifer Species

Many plant tissues, including phloem and xylem from loblolly pine (Pinus taeda L.), contain high levels of phenolics and polysaccharides that interfere with RNA purification. This presentation discusses techniques for the harvest of field-grown tissues and isolation of RNA of sufficient quality for microarrays and other genomic analyses.

Tissues isolated from conifer species, particularly those belonging to the Pinaceae family, such as loblolly pine (Pinus taeda L.), contain high ...

In vivo Imaging and Therapeutic Treatments in an Orthotopic Mouse Model of Ovarian Cancer

Human cancer and response to therapy is better represented in orthotopic animal models. This paper describes the development of an orthotopic mouse model of ovarian cancer, treatment of cancer via oral delivery of drugs, and monitoring of tumor cell behavior in response to drug treatment in real time using in vivo imaging system. In this orthotopic model, ovarian tumor cells expressing luciferase are applied topically by injecting them directly into the mouse bursa where each ovary is enclosed. Upon injection of D-luciferin, a substrate of firefly luciferase, luciferase-expressing cells generate bioluminescence signals. This signal is detected by the in vivo imaging system and allows for a non-invasive means of monitoring tumor growth, distribution, and regression in individual animals. Drug administration via oral gavage allows for a maximum dosing volume of 10 mL/kg body weight to be delivered directly to the stomach and closely resembles delivery of drugs in clinical treatments. Therefore, techniques described here, development of an orthotopic mouse model of ovarian cancer, oral delivery of drugs, and in vivo imaging, are useful for better understanding of human ovarian cancer and treatment and will improve targeting this disease.

In vivo Imaging and Therapeutic Treatments in an Orthotopic Mouse Model of Ovarian Cancer

Orthotopic animal models of ovarian cancer replicate better human disease and therefore enhance our understanding of cancer progression and tumor response to therapy. A mouse model receives an intrabursal injection of luciferase-expressing ovarian tumor cells. Treatment is administered via oral gavage. Tumor growth is monitored by in vivo imaging system.

Human cancer and response to therapy is better represented in orthotopic animal models.  This paper describes the development of an orthotopic mouse model ...

Isolation of Primary Mouse Trophoblast Cells and Trophoblast Invasion Assay

The placenta is responsible for the transport of nutrients, gasses and growth factors to the fetus, as well as the elimination of wastes. 
Thus, defects in placental development have important consequences for the fetus and mother, and are a major cause of embryonic lethality. The major cell type of the 
fetal portion of the placenta is the trophoblast. Primary mouse placental trophoblast cells are a useful tool for studying normal and abnormal placental development, 
and unlike cell lines, may be isolated and used to study trophoblast at specific stages of pregnancy. In addition, primary cultures of trophoblast from transgenic
mice may be used to study the role of particular genes in placental cells. The protocol presented here is based on the description by Thordarson et al.1, in which a 
percoll gradient is used to obtain a relatively pure trophoblast cell population from isolated mouse placentas. It is similar to the more widely used methods for 
human trophoblast cell isolation2-3. Purity may be assessed by immunocytochemical staining of the isolated cells for cytokeratin 74. Here, the isolated cells are 
then analyzed using a matrigel invasion assay to assess trophoblast invasiveness in vitro5-6. The invaded cells are analyzed by immunocytochemistry and stained 
for counting.

In this protocol, we describe the dissection of placentae from the mouse on pregnancy d10.5, followed by isolation of trophoblast cells using a Percoll gradient. We then demonstrate use of the isolated cells in a matrigel invasion assay.

The placenta is responsible for the transport of nutrients, gasses and growth factors to the fetus, as well as the elimination of wastes.  
Thus, defects ...

Isolation and Culture of Mouse Primary Pancreatic Acinar Cells

This protocol permits rapid isolation (in less than 1 hr) of murine pancreatic acini, making it possible to maintain them in culture for more than one week. More than 20 x 106 acinar cells can be obtained from a single murine pancreas. This protocol offers the possibility to independently process as many as 10 pancreases in parallel. Because it preserves acinar architecture, this model is well suited for studying the physiology of the exocrine pancreas in vitro in contrast to cell lines established from pancreatic tumors, which display many genetic alterations resulting in partial or total loss of their acinar differentiation.

In this publication, we describe a rapid and convenient procedure for isolating and culturing primary pancreatic acinar cells from the murine pancreas. This method constitutes a valuable approach to study the physiology of fresh primary normal/untransformed exocrine pancreatic cells.

This protocol permits rapid isolation (in less than 1 hr) of murine pancreatic acini, making it possible to maintain them in culture for more than one ...

Isolation of Primary Myofibroblasts from Mouse and Human Colon Tissue

The myofibroblast is a stromal cell of the gastrointestinal (GI) tract that has been gaining considerable attention for its critical role in many GI functions. While several myofibroblast cell lines are commercially available to study these cells in vitro, research results from a cell line exposed to experimental cell culture conditions have inherent limitations due to the overly reductionist nature of the work. Use of primary myofibroblasts offers a great advantage in terms of confirming experimental findings identified in a cell line. Isolation of primary myofibroblasts from an animal model allows for the study of myofibroblasts under conditions that more closely mimic the disease state being studied. Isolation of primary myofibroblasts from human colon tissue provides arguably the most relevant experimental data, since the cells come directly from patients with the underlying disease. We describe a well-established technique that can be utilized to isolate primary myofibroblasts from both mouse and human colon tissue. These isolated cells have been characterized to be alpha-smooth muscle actin and vimentin-positive, and desmin-negative, consistent with subepithelial intestinal myofibroblasts. Primary myofibroblast cells can be grown in cell culture and used for experimental purposes over a limited number of passages.

The myofibroblast is an influential stromal cell of the gastrointestinal tract that regulates important physiologic processes in both normal and disease states. We describe a technique that allows for the isolation of primary myofibroblasts from both mouse and human colon tissue, which can be utilized for in vitro experimentation.

The myofibroblast is  a stromal cell of the gastrointestinal (GI) tract that has been gaining  considerable attention for its critical role in many GI ...

Isolation and Primary Culture of Mouse Aortic Endothelial Cells

The vascular endothelium is essential to normal vascular homeostasis. Its dysfunction participates in various cardiovascular disorders. The mouse is an important model for cardiovascular disease research. This study demonstrates a simple method to isolate and culture endothelial cells from the mouse aorta without any special equipment. To isolate endothelial cells, the thoracic aorta is quickly removed from the mouse body, and the attached adipose tissue and connective tissue are removed from the aorta. The aorta is cut into 1 mm rings. Each aortic ring is opened and seeded onto a growth factor reduced matrix with the endothelium facing down. The segments are cultured in endothelial cell growth medium for about 4 days. The endothelial sprouting starts as early as day 2. The segments are then removed and the cells are cultured continually until they reach confluence. The endothelial cells are harvested using neutral proteinase and cultured in endothelial cell growth medium for another two passages before being used for experiments. Immunofluorescence staining indicated that after the second passage the majority of cells were double positive for Dil-ac-LDL uptake, Lectin binding, and CD31 staining, the typical characteristics of endothelial cells. It is suggested that cells at the second to third passages are suitable for in vitro and in vivo experiments to study the endothelial biology. Our protocol provides an effective means of identifying specific cellular and molecular mechanisms in endothelial cell physiopathology.

The vascular endothelial cells play a significant role in many important cardiovascular disorders. This article describes a simple method to isolate and expand endothelial cells from the mouse aorta without using any special equipment. Our protocol provides an effective means of identifying mechanisms in endothelial cell physiopathology.

The vascular endothelium is essential to normal vascular homeostasis. Its dysfunction participates in various cardiovascular disorders. The mouse is an ...

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.

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

Isolation and Culture of Primary Mouse Keratinocytes from Neonatal and Adult Mouse Skin

The keratinocyte (KC) is the predominant cell type in the epidermis, the outermost layer of the skin. Epidermal KCs play a critical role in providing skin defense by forming an intact skin barrier against environmental insults, such as UVB irradiation or pathogens, and also by initiating an inflammatory response upon those insults. Here we describe methods to isolate KCs from neonatal mouse skin and from adult mouse tail skin. We also describe culturing conditions using defined growth supplements (dGS) in comparison to chelexed fetal bovine serum (cFBS). Functionally, we show that both neonatal and adult KCs are highly responsive to high calcium-induced terminal differentiation, tight junction formation and stratification. Additionally, cultured adult KCs are susceptible to UVB-triggered cell death and can release large amounts of TNF upon UVB irradiation. Together, the methods described here will be useful to researchers for the setup of in vitro models to study epidermal biology in the neonatal mouse and/or the adult mouse.

Epidermal keratinocytes form a functional skin barrier and are positioned at the front line of host defense against external environmental insults. Here we describe methods for isolation and primary culture of epidermal keratinocytes from neonatal and adult mouse skin, and induction of terminal differentiation and UVB-triggered inflammatory response from keratinocytes.

The keratinocyte (KC) is the predominant cell type in the epidermis, the outermost layer of the skin. Epidermal KCs play a critical role in providing skin ...

Efficient Dissection and Culture of Primary Mouse Retinal Pigment Epithelial Cells

Eye disorders affect millions of people worldwide, but the limited availability of human tissues hinders their study. Mouse models are powerful tools to understand the pathophysiology of ocular diseases because of their similarities with human anatomy and physiology. Alterations in the retinal pigment epithelium (RPE), including changes in morphology and function, are common features shared by many ocular disorders. However, successful isolation and culture of primary mouse RPE cells is very challenging. This paper is an updated audiovisual version of the protocol previously published by Fernandez-Godino et al. in 2016 to efficiently isolate and culture primary mouse RPE cells. This method is highly reproducible and results in robust cultures of highly polarized and pigmented RPE monolayers that can be maintained for several weeks on Transwells. This model opens new avenues for the study of the molecular and cellular mechanisms underlying eye diseases. Moreover, it provides a platform to test therapeutic approaches that can be used to treat important eye diseases with unmet medical needs, including inherited retinal disorders and macular degenerations.

This protocol, which was originally reported by Fernandez-Godino et al. in 20161, describes a method to efficiently isolate and culture mouse RPE cells, which form a functional and polarized RPE monolayer within one week on Transwell plates. The procedure takes approximately 3 hours.

Eye disorders affect millions of people worldwide, but the limited availability of human tissues hinders their study. Mouse models are powerful tools to ...