Name: a human 3d extracellular matrix-adipocyte culture model for studying matrix-cell metabolic crosstalk
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Description: Watch this Scientific Journal Video about A Human 3D Extracellular Matrix-Adipocyte Culture Model for Studying Matrix-Cell Metabolic Crosstalk at JoVE.com

We thank Danielle Berger, Marilyn Woodruff, Simone Correa, and Retha Geiss for assistance with study coordination. SEM was performed by University of Michigan Microscopy &#38; Image Analysis Laboratory Biomedical Research Core Facility. This project was supported by NIH grants R01DK097449 (RWO), R01DK115190 (RWO, CNL), R01DK090262 (CNL), Veterans Affairs Merit Grant I01CX001811 (RWO), Pilot and Feasibility Grant from the Michigan Diabetes Research Center (NIH Grant P30-DK020572) (RWO), Veterans Administration VISN 10 SPARK Pilot Grant (RWO). Scanning electron microscopy performed by the University of Michigan Microscopy &#38; Image Analysis Laboratory Biomedical Research Core Facility. Figure 4 of this manuscript was originally published in Baker et al., J Clin Endo Metab 2017; Mar 1;102 (3), 1032-1043. doi: 10.1210/jc.2016-2915, and has been reproduced by permission of Oxford University Press [https://academic.oup.com/jcem/article/102/3/1032/2836329]. For permission to reuse this material, please visit http://global.oup.com/academic/rights.

Adipose tissues are procured from human subjects undergoing elective bariatric surgery under institutional review board approval.
1. Preadipocyte isolation and culture reagent preparation
<ol>
	<li>Prepare 2% bovine serum albumin (BSA) in 1x phosphate buffered saline solution (PBS). Filter sterilize, and store at 4 &#176;C.</li>
	<li>Prepare Type II collagenase: 2 mg/mL in 2% BSA in 1x PBS. Prepare immediately before use.</li>
	<li>Prepare Red Blood Cell (RBC) Lysing Solution: 1.5 M NH4...

<ol>
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The ECM-adipocyte culture model provides a valuable tool for dissecting the individual roles of ECM and cells in dictating ultimate tissue phenotype. The ECM isolation protocol is quite reproducible, but variability in the decellularization process may be observed. The Day 3 delipidation step is a critical point in the protocol. At the completion of the overnight extraction, delipidation of the matrix should be evidenced by the Polar Solvent Solution turning yellow, while the matrix should transition from a yellow-orange...

The extracellular matrix (ECM) not only provides a mechanical scaffold for tissues, but also engages in complex crosstalk with cells that reside within it, regulating diverse processes necessary for tissue homeostasis, including cell proliferation, differentiation, signaling, and metabolism1. While healthy ECM plays an essential role the maintenance of normal tissue function, dysfunctional ECM has been implicated in multiple diseases2.
Adipose tissue plays an important role in the pathogenesis of metabolic disease. Obesity is associated with excessive adipocyte hypertrophy and cellular hypoxia, defects in adipocyte cellular metabolism, and adipose tissue endoplasmic reticulum and oxidative stress and inflammation. While poorly understood, these complex processes conspire to impair adipose tissue nutrient buffering capacity, leading to nutrient overflow from adipose tissue, toxicity in multiple tissues, and systemic metabolic disease3,4,5.The sequence of events and specific mechanisms that underlie adipose tissue failure are poorly understood, but alterations in adipose tissue ECM have been implicated. The ECM composition is altered within adipose tissue in human and murine obesity, with increased deposition of ECM protein along with qualitative biochemical and structural differences in the adipose tissue ECM associated with human metabolic disease, including type 2 diabetes and hyperlipidemia6,7,8,9,10,11.
Despite these observations, the role of adipose tissue ECM in mediating adipose tissue dysfunction is not well-defined. This is in part due to a lack of tractable experimental models that permit dissection of the specific roles of ECM and adipocytes in regulating ultimate adipose tissue function. ECM-adipocyte culture better simulates the in vivo environment of native adipose tissue in at least two respects. Firstly, ECM culture provides a molecular environment similar to native adipose tissue, including native collagens, elastins, and other matrix proteins absent in standard 2D culture. Secondly, culture on 2D plastic has been shown to alter adipocyte metabolism via mechanical effects due to decreased elasticity of plastic substrate12, which ECM-culture eliminates.
Methods to engineer biological scaffolds by isolation of ECM from decellularized adipose and other tissues have been studied in the context of regenerative and reconstructive medicine and tissue engineering13,14,15,16,17,18. We have previously published methodology in which we adapted these methods to develop an in vitro 3D model of human ECM-adipocyte culture, using ECM and adipocyte stem cells (preadipocytes) derived from human visceral adipose tissues11. In the present article, we describe these methods in detail. The decellularization procedure for human adipose tissue is a four-day process that involves mechanical and enzymatic treatments to remove cells and lipid, leaving a biological scaffold that maintains characteristics of the tissue from which it is derived. Decellularized ECM supports adipogenic differentiation of human preadipocytes, and when reconstituted with adipocytes, maintains microarchitecture and biochemical and disease-specific characteristics of intact adipose tissue and engages in metabolic functions characteristic of native adipose tissue. This matrix can be studied alone or reseeded with cells, permitting study of interactions and crosstalk between the cellular and extra-cellular components of adipose tissue.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.25% trypsin-EDTA</td>
			<td>Gibco, ThermoFisher Scientific Inc., Waltham, MA, USA</td>
			<td>Cat#25200056</td>
			<td></td>
		</tr>
		<tr>
			<td>1.5 mL cryovial tube</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#02-682-557</td>
			<td></td>
		</tr>
		<tr>
			<td>10% Neutral Buffered Formalin</td>
			<td>VWR International LLC., Radnor, PA, USA</td>
			<td>Cat#89370-094</td>
			<td></td>
		</tr>
		<tr>
			<td>100 &#181;m nylon mesh filter</td>
			<td>Corning Inc., Corning, NY, USA</td>
			<td>Cat#352360</td>
			<td></td>
		</tr>
		<tr>
			<td>2-Deoxy-D-glucose</td>
			<td>Sigma-Aldrich, Inc., St Louis, MO, USA</td>
			<td>Cat#D8375</td>
			<td></td>
		</tr>
		<tr>
			<td>2 nM 3,3&#8217;-5,Triiodo,L-thyronine sodium salt (T3)</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#T6397</td>
			<td></td>
		</tr>
		<tr>
			<td>24-well tissue culture plates</td>
			<td>VWR International LLC., Radnor, PA, USA</td>
			<td>Cat#10861-700</td>
			<td></td>
		</tr>
		<tr>
			<td>3-Isobutyl-1-methylxanthine (IBMX)</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#I5879</td>
			<td></td>
		</tr>
		<tr>
			<td>96-well tissue culture plates</td>
			<td>VWR International LLC., Radnor, PA, USA</td>
			<td>Cat#10861-666</td>
			<td></td>
		</tr>
		<tr>
			<td>Antibiotic-Antimycotic Solution (ABAM)</td>
			<td>Gibco, ThermoFisher Scientific Inc., Waltham, MA, USA</td>
			<td>Cat#15240062</td>
			<td></td>
		</tr>
		<tr>
			<td>Biotin</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#B4639</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine Serum Albumin (BSA)</td>
			<td>Sigma-Aldrich, Inc., St Louis, MO, USA</td>
			<td>Cat#A8806</td>
			<td></td>
		</tr>
		<tr>
			<td>Buffer RLT</td>
			<td>Qiagen, Hilden, Germany</td>
			<td>Cat#79216</td>
			<td></td>
		</tr>
		<tr>
			<td>Ciglitizone</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#C3974</td>
			<td></td>
		</tr>
		<tr>
			<td>Deoxy-D-glucose, 2-[1,2-3H (N)]-</td>
			<td>PerkinElmer Inc., Waltham, MA, USA</td>
			<td>Cat#NET328A250UC</td>
			<td></td>
		</tr>
		<tr>
			<td>Deoxyribonuclease I from bovine pancreas, type II-S</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#D4513</td>
			<td></td>
		</tr>
		<tr>
			<td>Dexamethasone</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#D4902</td>
			<td></td>
		</tr>
		<tr>
			<td>Dimethyl Sulfoxide</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#BP231</td>
			<td>Flammable, caustic</td>
		</tr>
		<tr>
			<td>Disodium EDTA</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#BP118</td>
			<td></td>
		</tr>
		<tr>
			<td>D-pantothenic acid hemicalcium salt</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#21210</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#8217;s Modified Eagle Medium: Nutrient Mixture F-12 (DMEM/F12</td>
			<td>Gibco, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#11320033</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>Decon Labs, Inc., King of Prussia, PA, USA</td>
			<td>Cat#DSP-MD.43</td>
			<td>Flammable</td>
		</tr>
		<tr>
			<td>EVE Cell Counting Slides, NanoEnTek</td>
			<td>VWR International LLC., Radnor, PA, USA</td>
			<td>Cat#10027-446</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal bovine serum (FBS)</td>
			<td>Gibco, ThermoFisher Scientific Inc., Waltham, MA, USA</td>
			<td>Cat#10437028</td>
			<td></td>
		</tr>
		<tr>
			<td>Glutaraldehyde</td>
			<td>Sigma-Aldrich, Inc., St Louis, MO, USA</td>
			<td>Cat#G5882</td>
			<td>Caustic</td>
		</tr>
		<tr>
			<td>Hexamethyldisalizane</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#440191</td>
			<td>Flammable, caustic</td>
		</tr>
		<tr>
			<td>Human insulin solution</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#I9278</td>
			<td></td>
		</tr>
		<tr>
			<td>Isopropanol</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#A415</td>
			<td>Flammable</td>
		</tr>
		<tr>
			<td>Isoproterenol</td>
			<td>Sigma-Aldrich, Inc., St Louis, MO, USA</td>
			<td>Cat#I5627</td>
			<td>Flammable</td>
		</tr>
		<tr>
			<td>KCl</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#S25484</td>
			<td></td>
		</tr>
		<tr>
			<td>KH2PO4</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#P5655</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipase from porcine pancreas, type VI-S</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#L0382</td>
			<td></td>
		</tr>
		<tr>
			<td>MgSO4*7H2O</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#230391</td>
			<td></td>
		</tr>
		<tr>
			<td>Na2HPO4</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#S5136</td>
			<td></td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#S3014</td>
			<td></td>
		</tr>
		<tr>
			<td>NaHCO3</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#S233</td>
			<td></td>
		</tr>
		<tr>
			<td>NH4Cl</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#A661</td>
			<td></td>
		</tr>
		<tr>
			<td>Optimal cutting temperature (OCT) compound</td>
			<td>Agar Scientific, Ltd., Stansted, Essex, UK</td>
			<td>Cat# AGR1180</td>
			<td></td>
		</tr>
		<tr>
			<td>Oil Red-O Solution (ORO)</td>
			<td>Sigma-Aldrich, Inc., St Louis, MO, USA</td>
			<td>Cat#O1391</td>
			<td></td>
		</tr>
		<tr>
			<td>Oil Red-O Stain Kit</td>
			<td>American Master Tech Scientific Inc., Lodi, CA, USA</td>
			<td>Cat#KTORO-G</td>
			<td></td>
		</tr>
		<tr>
			<td>Osmium tetroxide</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#201030</td>
			<td>Caustic</td>
		</tr>
		<tr>
			<td>Phenylmethylsulfonyl fluoride (PMSF)</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#93482</td>
			<td>Caustic</td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline Solution (PBS)</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#SH3025601</td>
			<td></td>
		</tr>
		<tr>
			<td>Ribonuclease A from bovine pancreas, type III-A</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#R5125</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAEasy Fibrous Tissue MiniKit</td>
			<td>Qiagen, Hilden, Germany</td>
			<td>Cat#74704</td>
			<td></td>
		</tr>
		<tr>
			<td>Scintillation Fluid</td>
			<td>Fisher Scientific, ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#SX18</td>
			<td></td>
		</tr>
		<tr>
			<td>Scintillation Counter</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Scissors, forceps, sterile</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sorensen&#39;s phosphate buffer</td>
			<td>Thomas Scientific, Inc., Swedesboro, NJ</td>
			<td>CAS #: 10049-21-5</td>
			<td></td>
		</tr>
		<tr>
			<td>T-150 culture flask</td>
			<td>VWR International LLC., Radnor, PA, USA</td>
			<td>Cat#10062-864</td>
			<td></td>
		</tr>
		<tr>
			<td>TaqMan Gene Expression Master Mix</td>
			<td>ThermoFisher Scientific Inc., Waltham, MA USA</td>
			<td>Cat#4369016</td>
			<td></td>
		</tr>
		<tr>
			<td>Temperature-controlled orbital shaker</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Tissue Homogenizer, BeadBug Microtube Homogenizer</td>
			<td>Benchmark Scientific</td>
			<td>Cat#D1030</td>
			<td></td>
		</tr>
		<tr>
			<td>Transferrin</td>
			<td>Sigma-Aldrich, Inc. St Louis, MO, USA</td>
			<td>Cat#T3309</td>
			<td></td>
		</tr>
		<tr>
			<td>Triglyceride Determination Kit</td>
			<td>Sigma-Aldrich, Inc., St Louis, MO, USA</td>
			<td>Cat#TR0100</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan blue stain, 0.4%</td>
			<td>VWR International LLC., Radnor, PA, USA</td>
			<td>Cat#10027-446</td>
			<td></td>
		</tr>
		<tr>
			<td>Type II collagenase</td>
			<td>Gibco, ThermoFisher Scientific Inc., Waltham, MA, USA</td>
			<td>Cat#17101015</td>
			<td></td>
		</tr>
		<tr>
			<td>Whatman Reeve Angel filter paper, Grade 201, 150mm</td>
			<td>Sigma-Aldrich, Inc., St Louis, MO, USA</td>
			<td>Cat#WHA5201150</td>
			<td></td>
		</tr>
	</tbody>
</table>

a human 3d extracellular matrix-adipocyte culture model for studying matrix-cell metabolic crosstalk

The extracellular matrix (ECM) plays a central role in regulating tissue homeostasis, engaging in crosstalk with cells and regulating multiple aspects of cellular function. The ECM plays a particularly important role in adipose tissue function in obesity, and alterations in adipose tissue ECM deposition and composition are associated with metabolic disease in mice and humans. Tractable in vitro models that permit dissection of the roles of the ECM and cells in contributing to global tissue phenotype are sparse. We describe a novel 3D in vitro model of human ECM-adipocyte culture that permits study of the specific roles of the ECM and adipocytes in regulating adipose tissue metabolic phenotype. Human adipose tissue is decellularized to isolate ECM, which is subsequently repopulated with preadipocytes that are then differentiated within the ECM into mature adipocytes. This method creates ECM-adipocyte constructs that are metabolically active and retain characteristics of the tissues and patients from which they are derived. We have used this system to demonstrate disease-specific ECM-adipocyte crosstalk in human adipose tissue. This culture model provides a tool for dissecting the roles of the ECM and adipocytes in contributing to global adipose tissue metabolic phenotype and permits study of the role of the ECM in regulating adipose tissue homeostasis.

Preparation of adipose tissue ECM, seeding with preadipocytes, and in vitro differentiation into mature adipocytes result in clear sequential morphologic changes in tissue that permits visual assessment of progress throughout the protocol (Figure 1). Preadipocytes used to seed the ECM are isolated using collagenase digestion from separate VAT samples (Figure 2). Scanning electron microscopy of ECM-adipocyte constructs at each sta...

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A Human 3D Extracellular Matrix-Adipocyte Culture Model for Studying Matrix-Cell Metabolic Crosstalk

We describe a 3D human extracellular matrix-adipocyte in vitro culture system that permits dissection of the roles of the matrix and adipocytes in contributing to adipose tissue metabolic phenotype.

The extracellular matrix (ECM) plays a central role in regulating tissue homeostasis, engaging in crosstalk with cells and regulating multiple aspects of ...

Our protocol demonstrates that the ECM may promote adipogenic differentiation in the absence of classic adipogenic mediators and is the first to demonstrate disease-specific regulation of cellular metabolism by the ECM. Our technique provides a tool for dissecting the roles of the ECM and adipocytes in adipose tissue metabolism and permit study of the role of the ECM in regulating adipose tissue homeostasis. Compared with standard 2D cell culture, our 3D model allows for more robust examination and dissection of cross-talk between adipocytes and adipose tissue ECM in the context of type 2 diabetes.We recommend beginning with smaller samples to gauge how well it is cellularized. Keep in mind there is interpatient variability in how well the cells grow and how well the tissue decellularizes. It is important to observe the tissue before and after each step to ensure the tissue is becoming decellularized and to understand potential differences between samples.After obtaining visceral adipose tissue or VAT from surgery, prepare it for storage by adding 5-10 grams of the tissue to 15-25 milliliters of freezing buffer solution in a 50 milliliter conical tube. Completely immerse the sample and store it at minus 80 degrees Celsius until decellularization. For preadipocyte isolation, place two grams of a fresh sample of intact VAT in 20 milliliters of collagenase type II solution, then insert sterile scissors into the tube and thoroughly mince the tissue.Once minced to a fine slurry, incubate it in the collagenase solution at 37 degrees Celsius on an orbital shaker for 60 minutes. After the incubation, filter the resultant digested through a 100 micrometer nylon mesh into a fresh 50 milliliter conical tube. The digested should be a yellow-orange liquid with moderate viscosity and a small amount of residual strands of undigested tissue.Centrifuge the sample at 270 times g for 10 minutes, remove the supernatant and resuspend the cell pellet in two milliliters of 1X RBC lysing solution with a pipette. Incubate the solution for one minute at 25 degrees Celsius, then add 10 milliliters of 15%FBS DMEM F12 and centrifuge it at 270 times g for 10 minutes. To prepare the ECM, freeze/thaw the previously frozen VAT sample to 37 degrees Celsius by incubating it in a pre-heated water bath for 20 minutes with periodic gentle manual agitation.Once thawed, transfer the tissue back to minus 80 degrees Celsius for 20 minutes and repeat the freeze/thaw process three times ending with the thawing. Use sterile forceps to transfer the VAT sample to a fresh 50 milliliter conical tube containing 15-25 milliliters of enzymatic solution 1 making sure that the sample is fully immersed. Then incubate it overnight at 37 degrees Celsius while shaking at 130 RPM.On the next day, wash the sample three times with 15-25 milliliters of rinsing buffer solution, pouring off the solution after each wash. Transfer the sample to a fresh 50 milliliter tube with 15-25 milliliters of enzymatic solution 2 and incubate it overnight. Repeat the washes with the rinsing buffer solution and transfer the sample to a fresh tube containing 15-25 milliliters of polar solvent extraction solution.Incubate the sample overnight while shaking. After incubation with the polar solvent solution, it is important to examine the sample for lipid removal. If most of the lipid is not removed, it may be necessary to repeat this step.Shorter incubation time may be used. After the incubation, transfer the sample to a fresh tube containing 15-25 milliliters of rinsing buffer solution and wash the sample three times on the shaker. Then wash the sample three times with 70%ethanol solution, pouring off the ethanol after each wash.Wash the sample once with storage solution, then use sterile forceps to transfer to a fresh tube containing 15-25 milliliters of storage solution making sure to fully immerse it. The sample can then be stored at four degrees Celsius for up to one month. The isopropanol and ethanol are flammable and must be at room temperature and disposed of in flammable waste.Any human waste must be disposed of separately from the usual biohazard waste. Transfer the stored ECM fragments to individual wells of a 24-well plate with sterile forceps adding as many fragments as required for the planned downstream assays. Wash them three times with 500 microliters of 70%ethanol on an orbital shaker, then rehydrate them by washing three times with PBS.Use sterile scissors to cut the ECM into 100 milligram fragments. Place each fragment into one well of a 24-well plate and incubate the plate at 25 degrees Celsius for 15 minutes to allow excess PBS to extrude from the fragments. Then carefully remove any leftover PBS from the wells with a pipette.Seed each fragment with 20 microliters of preadipocyte cell suspension by pipetting the cells directly into the ECM. Place the pipette tip in the ECM and gently expel it into the center of the matrix making sure that the cell suspension does not overflow and end up at the bottom of the well. If the cell suspension overflows from the ECM, remove the pipette tip from that location and insert it elsewhere in the ECM.After cell seeding, incubate the ECM for 40 minutes at 37 degrees Celsius. Fill each well with 500 microliters of growth media to cover the seeded ECM fragments. Culture the cells at 37 degrees Celsius and 5%carbon dioxide for 72 hours.After 72 hours, carefully aspirate the growth media without disturbing the ECM fragment. Add 500 microliters of differentiation media and culture the cells for 14 days changing the media every two to three days. Check for differentiation using light microscopy.Cells will accumulate lipids, turn brown-yellow in color and become more spherical as they differentiate. Preparation of adipose tissue ECM, seeding with preadipocytes, and in vitro differentiation into mature adipocytes was monitored with scanning electron microscopy which revealed decellularization of ECM and subsequent recapitulation of lipid containing adipocytes upon reseeding and differentiation. Collagen 1 specific immunohistochemistry of decellularized ECM showed maintenance of collagen micro architecture while Oil Red-O staining of live and fixed 3D ECM-adipocyte constructs showed lipid containing adipocytes.The adipocytes differentiated in ECM were screened for adipogenic genes using quantitative real-time PCR which demonstrated that these genes are upregulated in the differentiated cells relative to undifferentiated preadipocytes cultured in ECM. The full difference in transcript levels is shown. Four combinations of ECM and adipocytes from diabetic and nondiabetic subjects were subjected to metabolic phenotyping.Impaired glucose uptake in lipolytic function was discovered in constructs from diabetic tissues. Importantly, it was found that nondiabetic ECM rescues insulin-stimulated glucose uptake and lipolytic capacity in diabetic adipocytes. Contamination of the isolated preadipocytes, the decellularized tissue, and the reseeded ECM is not uncommon.Sterility must be diligently maintained throughout the protocol.

Research

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Bioengineering

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