This research was supported by a grant from the Korea Health Technology R&#38;D Project through the Korea Health Industry Development Institute (KHIDI), which was funded by the Ministry of Health &#38; Welfare, Republic of Korea (grant number: HI16C1559).

The protocol was conducted in accordance with the Declaration of Helsinki and the protocol was approved by the Institutional Review Board at CHA Bundang Medical Center.
1. Degenerative Tendon Tissue Harvest from the Patient
<ol>
	<li>Diagnose lateral epicondylitis by taking a medical history and using physical exam findings: tenderness over the tendinous origin close to the lateral epicondyle; pain evoked by resisted extension of the wrist joint.</li>
	<li>Use the following inclusion criteria: over 18 years of age; a history of lateral epicondylitis for a minimum of six months; recalcitrant for non-operative treatment; at least three months have passed since injection of corticosteroid, platelet rich plasma, or botulinum toxin</li>
	<li>Exclude the following: pregnant women; patients with a history of cervical spine disease, elbow arthritis, rheumatologic disease, surgery around elbow, and nerve entrapment syndrome; patients refusing to donate tissue.</li>
	<li>Surgical technique 
	&#8203;NOTE: See Figure 124.
	<ol>
		<li>After general anesthesia by isoflurane and endotracheal intubation, put the arm on the table and apply a tourniquet. Then apply betadine agent on the whole arm and drape with an aseptic surgical sheet.</li>
		<li>Expose the lateral elbow through a 3&#8211;5 cm incision with No. 15 surgical scalpel blade just anteromedial to the lateral epicondyle and proximal to the level of the joint.</li>
		<li>Visually identify the extensor carpi radialis longus (ECRL) and extensor aponeurosis interface and make a splitting incision 2&#8211;3 mm in depth between the ECRL and extensor aponeurosis with a No. 15 surgical scalpel blade at the identified interface.</li>
		<li>Extract the ECRL anteriorly, which will bring the pathologic extensor carpi radialis longus brevis (ECRB) origin below into direct view.</li>
		<li>Visually identify the pathologic degenerative tissue by its characteristic dull grayish color and usually edematous and friable tissue.</li>
		<li>After identification, carefully resect all degenerative tissue sharply using No. 15 surgical scalpel and mini-blades.</li>
		<li>Embed the resected tissue (about 1 cm3) into phosphate buffered saline (PBS) immediately and remove all the surrounding tissue except tendon tissue carefully into about 10 mL of PBS as soon as possible.</li>
		<li>In cases with bony exostosis at the lateral epicondyle, remove exostosis using a rongeur and smoothen it with a rasp. Make multiple drill holes (diameter 1.6 mm, about 6&#8211;8 holes) in the anterolateral condyle to enhance vascular supply. This is optional.</li>
		<li>Close the wound layer by layer using non-absorbable suture material.</li>
	</ol>
	</li>
	<li>Healthy control tenocyte
	<ol>
		<li>Obtain healthy tenocytes from the remaining tendon of the auto-hamstring or auto-patella tendon during anterior cruciate ligament reconstruction, and use it as the control for the following experiment25. 
		NOTE: The number of samples used in this study were three in each group.</li>
	</ol>
	</li>
</ol>
2. Histology
<ol>
	<li>Store about half of the harvested tissue in neutral buffered 10% formalin in a chemical fume hood or equivalent.</li>
	<li>Embed the tissue in a paraffin block (4&#8211;5 mL) and section it in 4&#8211;5 &#181;m sections coronally.</li>
	<li>Stain sections from control and degenerative tendon with Hematoxylin and Eosin stain (H&#38;E) and Alcian blue stain at a pH of 2.5. Perform H&#38;E staining in an automated stain machine as follows.
	<ol>
		<li>Deparaffinize using xylene (3 times, 5 min, respectively).</li>
		<li>Hydrate from graded alcohols to water (100% alcohol, 4 min; 100% alcohol, 3 min; 95% alcohol, 2 min; 70% alcohol, 1 min; water, 2 min).</li>
		<li>Stain in Hematoxylin for 5 min. Wash well in water for 2 min.</li>
		<li>Differentiate in 1% acid alcohol (1% HCl in 70% alcohol) for 3 s. Wash well in water for 3 min.</li>
		<li>Neutralize HCl by dipping in an 0.5% ammonia for 10 s, followed by a 3 min water wash.</li>
		<li>Stain in Eosion for 5 min.</li>
		<li>Dehydrate through alcohols (80% alcohol, 30 s; 95% alcohol, 1 min; 100% alcohol 1 min, 100% alcohol 2 min).</li>
		<li>Clear in xylene (3 times, 2 min, 2 min, and 3 min, respectively).</li>
		<li>Mount with a cover slide.</li>
	</ol>
	</li>
	<li>Perform immunohistochemitry (IHC) using the Bond Polymer Refine Detection kit according to the manufacturer&#39;s instructions with minor modifications.
	<ol>
		<li>After deparaffinization using xylene, perform an antigen retrieval procedure using Bond Epitope Retrieval Solution for 30 min at 100 &#176;C. The Bond Epitope Retrieval Solution contains a citrate based buffer and surfactant (1 L, pH 5.9&#8211;6.1).</li>
		<li>Quench endogenous peroxidases by incubating the tissue with hydrogen peroxide for 5 min.</li>
		<li>Incubate the sections for 15 min at an ambient temperature (21-22 &#176;C) with primary antibodies against vascular endothelial growth factor (VEGF) (1:200), tenomodulin (1:200), or mohawk (1:200).</li>
		<li>Perform secondary antibody tagging with a biotin-free polymeric horseradish peroxidase-linker antibody conjugate system.
		<ol>
			<li>Use secondary rabbit anti mouse IgG in 10% (v/v) animal serum in Tris-buffered saline/0.09% 2-Methyl-4-isothiazolin-3-one solution to localize mouse antibodies.</li>
			<li>Use polymer anti-rabbit Poly-HRP-IgG (&#60;25 &#181;g/mL) containing 10% (v/v) animal serum in Tris-buffered saline/0.09% to localize rabbit antibodies.</li>
			<li>Use 3,3&#39;-Diaminobenzidine tetrahydrochloride hydrate in a stabilizer solution to visualize the complex via a brown precipitate.</li>
			<li>Counterstain with &#60;0.1% hematoxylin (blue) to visualize the cell nuclei.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Observe the slides stained with H&#38;E, Alcian blue stains, and IHC for VEGF, tenomodulin, and mohawk under light microscope and obtain representative microscopic images of each slide under one high power field (400X).</li>
</ol>
3. Tenocyte Culture
<ol>
	<li>Tissue preparation
	<ol>
		<li>Prepare the tendon sample by removing all the surrounding tissue thoroughly with micro-scissors and forceps.</li>
		<li>Wash with PBS and mince into small pieces (about 1 mm3 or less).</li>
		<li>Digest tissue for 1 h in 30 mL of Dulbecco&#39;s Modified Eagle&#39;s Medium (DMEM) supplemented with 30 mg/mL Collagenase II at 37 &#176;C.</li>
		<li>Pass cells through a 100 &#181;m cell strainer.</li>
		<li>Deactivate Collagenase II by adding 1 mL of fetal bovine serum (FBS).</li>
		<li>Centrifuge at 196 x g for 5 min.</li>
	</ol>
	</li>
	<li>Cell culture
	<ol>
		<li>Seed 3 x 105 cells into a 100 mm dish and culture with DMEM supplemented with 10% FBS and 1% Antibiotic-Antimycotic solution at 37 &#176;C in a 5% CO2 incubator for 1 week.</li>
		<li>Change the culture medium every three days until 80% confluence occurs. Culture both healthy control and degenerative cell samples until passage four and use for experiment.</li>
	</ol>
	</li>
</ol>
4. Immunocytochemistry (ICC)
<ol>
	<li>Transfer 200 &#181;L of cultured cell (2 x 105 cells) to the eight wells of a chamber slide and grow the cells to confluence with the addition of fresh media for 1 day.</li>
	<li>Wash the cells with PBS and fix with 500 &#181;L of 4% formaldehyde per well.</li>
	<li>Incubate the slides with 0.5% Triton X-100 in PBS for 10 min for permeabilization of the membranes.</li>
	<li>Block in PBS with 1% bovine serum albumin and 0.05% TWEEN-20 for mohawk and tenomodulin, respectively.</li>
	<li>Incubate in the dark with mouse anti-mohawk monoclonal antibody (1:100 dilution) and goat anti-tenomodulin antibody (1:100 dilution) at 4 &#176;C overnight.</li>
	<li>Incubate the secondary antibodies (Alexa 555-anti goat (1:200) for tenomodulin; Alexa 488-anti mouse (1:200) for mohawk) in the dark for 1 h at room temperature.</li>
	<li>Mount with 0.5 &#181;L of a fluorescence mounting medium.</li>
	<li>Analyze using a fluorescence microscope (400X).</li>
</ol>
5. Proliferation Assay
<ol>
	<li>Measure cell viabilities using water-soluble tetrazolium (WST)-1.
	<ol>
		<li>Seed both healthy and degenerative cells into 96 well plates at a density of 2 x 103 cells per well for 24, 72, and 120 h.</li>
		<li>After incubation, add 10 &#181;L of the 10% WST-1 solution to each well.</li>
		<li>Incubate the plates for 3 h at 37 &#176;C in 5% CO2.</li>
		<li>Measure the optical densities at 450 nm using a microplate reader. Take readings at least three times at all time points for each sample.</li>
	</ol>
	</li>
	<li>Measure cellular DNA amount using the BrdU assay.
	<ol>
		<li>Seed both healthy and degenerative cell into 96 well plates at a density of 2 x 103 cells per well for 24, 72, and 120 h.</li>
		<li>After incubation, add 10 &#181;L of 10% BrdU solution to each well.</li>
		<li>Incubate the plates for 3 h at 37 &#176;C in 5% CO2.</li>
		<li>Add 100 &#181;L/well of the Fixing/Denaturing Solution (60&#8211;70% ethanol, 0.1&#8211;0.5% sodium hydroxide) and keep the plate at room temperature for 30 min.</li>
		<li>Add 100 &#181;L/well prepared 1x detection antibody solution and keep the plate at room temperature for 1 h.</li>
		<li>Remove solution and wash plate three times with 1x Wash Buffer.</li>
		<li>Add 100 &#181;L/well prepared 1x HRP-conjugated secondary antibody solution and keep the plate at room temperature for 30 min.</li>
		<li>Remove the solution and wash plate three times with 1x Wash Buffer.</li>
		<li>Add 100 &#181;L of 50% TMB Substrate.</li>
		<li>Incubate for 30 min at room temperature.</li>
		<li>Add 100 &#181;L of STOP Solution.</li>
		<li>Measure the optical densities at 450 nm using a microplate reader. 
		NOTE: Take readings at least three times at all time points for each sample.</li>
	</ol>
	</li>
</ol>
6. Statistical Analysis
<ol>
	<li>Collect and analyze data using SPSS.</li>
	<li>Depict data by mean &#177; standard error of mean.</li>
	<li>Use Mann Whitney U test.</li>
	<li>Consider differences statistically significant when the p value is less than 0.05 (p &#60;0.05).</li>
</ol>

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The authors have nothing to disclose.

A number of previous studies have reported how to create chronic tendinopathic animal models using different procedures such as collagenase or kartogenin injection, treadmill running, and more26,27. Although numerous studies showed promising therapeutic effects based on these animal models, experiments using the human degenerative tenocyte would be crucial in the field of tendinopathy in order to reproduce the efficacy of treatment. In this article, we establishe...

Tendinopathy is a chronic degenerative musculoskeletal condition that develops in various parts of the body. Recently, the number of cases of tendinopathy has increased greatly in the developed world due to growing participation in recreational sports and increased life expectancy1,2. The cause of tendinopathy is considered to be multifactorial and these causes include ischemia, oxygen free radical injuries, an imbalance between vasoconstrictor and vasodilator innervations, internal micro-tears, and changes to neuro-regulation3,4,5,6,7,8. Most treatments for tendinopathy only relieve its symptoms. Moreover, treatments without tissue regeneration require a long time for rehabilitation and achieve a limited response from injured tendons, which imposes a clinical challenge for physicians9.
The incompetence of current treatment options along with the lack of the degenerative tendon&#39;s ability to self-heal has lead researchers to take interest in exploring alternative treatment strategies. Recently, new studies reported many promising results for enhancing the healing efficacy of the tendinopathy tendons using growth factors, stem cell based therapy, and gene therapy10,11,12.
Through a literature review, we found that the involved studies may be divided into two categories based on their analysis materials: animal models such as a rat, a mouse, or a rabbit; and human models. With regard to the animal model, currently there are two popular techniques to generate tendinopathy: chemical induction of injury or mechanical overloading the model. However, each animal model was limited in reproducing the complex human tendinopathy pathology13,14.
Most papers using human samples were analyzed histologically or performed the in vitro experiment based on a healthy human tenocyte instead of a degenerative tenocyte15,16,17,18,19,20,21. Only a few papers reported that they used a human degenerative tenocyte, but they did not describe in detail the protocol used to get the degenerative tenocyte from the human22,23. In this context, it should be noted that successful results from either the animal model or the healthy tissue/tenocyte may not necessarily predict human efficacy or efficacious dosing because tendon degeneration is a complicated process and the pathogenesis is still not fully understood.
Collectively, it is necessary to describe the standard protocol for obtaining the degenerative tenocyte from human tissue without causing adverse effects to the donor. This article describes a protocol on how to acquire the human degenerative tenocyte. To validate the protocol, the harvested tissues were analyzed histologically. Then, the cultured cell was confirmed as the degenerative tenocyte by using immunocytochemistry (ICC), a quantitative real time-polymerase chain reaction (qRT-PCR), and a viability assay.

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	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Scalpel</td>
			<td style="width:199px;">Kisanbio</td>
			<td style="width:119px;">KS-Q0306-15</td>
			<td style="width:167px;">No. 15</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Mini-blade</td>
			<td style="width:199px;">Beaver</td>
			<td style="width:119px;">374769</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:235px;">Dulbecco&#39;s modified Eagle&#39;s medium (DMEM)</td>
			<td style="width:199px;">Gibco</td>
			<td style="width:119px;">11995065</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Collagenase &#8545;</td>
			<td style="width:199px;">Sigma-Aldrich</td>
			<td style="width:119px;">C6885</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">PBS</td>
			<td>Gibco</td>
			<td style="width:119px;">14190250</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">fetal bovine serum (FBS)</td>
			<td>Gibco</td>
			<td style="width:119px;">16000044</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">50 mM ascorbic acid-2-phosphate</td>
			<td style="width:199px;">Sigma-Aldrich</td>
			<td style="width:119px;">A5960</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Antibiotic-Antimycotic solution</td>
			<td>Gibco</td>
			<td style="width:119px;">15240062</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">4% formaldehyde</td>
			<td style="width:199px;">Bio-solution</td>
			<td style="width:119px;">BP031</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Triton X-100&#160;</td>
			<td style="width:199px;">Sigma-Aldrich</td>
			<td style="width:119px;">X100-100ml</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">BSA</td>
			<td style="width:199px;">Rdtech</td>
			<td style="width:119px;">C0082</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">TWEEN 20</td>
			<td style="width:199px;">Sigma-Aldrich</td>
			<td style="width:119px;">P9416-100ml</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">MKX (C-5)</td>
			<td style="width:199px;">Santa cruz biotechnology</td>
			<td style="width:119px;">sc-515878</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Tenomodulin (N-14)</td>
			<td style="width:199px;">Santa cruz biotechnology</td>
			<td style="width:119px;">sc-49325</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Fluorescence Mounting Medium</td>
			<td style="width:199px;">DAKO</td>
			<td style="width:119px;">S3023</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:235px;">DAPI (4&#39;,6-Diamidino-2-Phenylindole, Dihydrochloride)</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">D1306</td>
			<td></td>
		</tr>
		<tr height="46">
			<td height="46" style="height:46px;width:235px;">WST-1</td>
			<td style="width:199px;">Dojindo Molecular Technologies</td>
			<td style="width:119px;">CK04</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">BrdU Cell Proliferation Assay Kit</td>
			<td style="width:199px;">Cell Signaling Technology</td>
			<td style="width:119px;">#6813</td>
			<td></td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;width:235px;">TRIzol Reagent</td>
			<td style="width:199px;">Invitrogen</td>
			<td style="width:119px;">15596018</td>
			<td></td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;width:235px;">iScript cDNA Synthesis Kit&#160;</td>
			<td style="width:199px;">Bio-Rad</td>
			<td style="width:119px;">170-8891</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:235px;">TaqMan Gene Expression Master Mix</td>
			<td style="width:199px;">Applied Biosystems</td>
			<td style="width:119px;">4369016</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">GAPDH</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">Hs02786624_g1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">COL3A1</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">Hs00943809_m1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">ACTA2</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">Hs00426835_g1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">TAC1</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">Hs00243225_m1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">TACR1</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">Hs00185530_m1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">PTGS2</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">Hs00153133_m1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">ACTB</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">Hs99999903_m1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Cell Strainers (100 &#181;m)&#160;</td>
			<td style="width:199px;">Corning</td>
			<td style="width:119px;">352360</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">100mm culture dish</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">8188207</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">8-well Chamber Slide</td>
			<td style="width:199px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">154534</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:235px;">96 Well Clear Flat Bottom Polystyrene TC-Treated Microplates</td>
			<td style="width:199px;">Corning</td>
			<td style="width:119px;">3596</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Nikon Eclipse 50i Microscope&#160;</td>
			<td style="width:199px;">Nikon</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;">VERSA max microplate reader&#160;</td>
			<td style="width:199px;">Molecular Devices</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:235px;">CFX96 Real-Time PCR Detection System</td>
			<td style="width:199px;">Bio-Rad</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:235px;">Formalin solution, neutral buffered, 10%</td>
			<td style="width:199px;">Sigma-Aldrich</td>
			<td style="width:119px;">HT501128</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Paraffins</td>
			<td style="width:199px;">Leica Biosystems</td>
			<td style="width:119px;">3801340</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Ethanol</td>
			<td style="width:199px;">JUNSEI CHEMICAL</td>
			<td style="width:119px;">90303-2185</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Hematoxylin</td>
			<td style="width:199px;">DAKO</td>
			<td style="width:119px;">CS70030-2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Eosin</td>
			<td style="width:199px;">DAKO</td>
			<td style="width:119px;">CS70130-2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Alcian blue</td>
			<td style="width:199px;">DAKO</td>
			<td style="width:119px;">AR16011-2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Citric acid</td>
			<td style="width:199px;">Sigma-Aldrich</td>
			<td style="width:119px;">251275</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Xylene</td>
			<td style="width:199px;">JUNSEI CHEMICAL</td>
			<td style="width:119px;">25165-0430</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Endogenous peroxidases&#160;</td>
			<td style="width:199px;">DAKO</td>
			<td style="width:119px;">S200380-2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Canada balsam</td>
			<td style="width:199px;">JUNSEI CHEMICAL</td>
			<td style="width:119px;">23255-1210</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Microtome Blade</td>
			<td style="width:199px;">FEATHER</td>
			<td style="width:119px;">A35</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Slide glass</td>
			<td style="width:199px;">SUPERIOR</td>
			<td style="width:119px;">1000612</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Cover glass</td>
			<td style="width:199px;">Marienfeld-Superior</td>
			<td style="width:119px;">101050</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">VEGF</td>
			<td style="width:199px;">Santa cruz biotechnology</td>
			<td style="width:119px;">sc-7269</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">SPSS Software</td>
			<td style="width:199px;">IBM</td>
			<td style="width:119px;"></td>
			<td>Ver. 18.0</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:235px;">Multi-purpose Centrifuge</td>
			<td style="width:199px;">LABOGENE</td>
			<td style="width:119px;">1248R</td>
			<td></td>
		</tr>
	</tbody>
</table>

a protocol to acquire the degenerative tenocyte from humans

Tendinopathy, a painful condition that develops in response to tendon degeneration, is on the rise in the developed world due to increasing physical activity and longer life expectancy. Despite its increasing prevalence, the underlying pathogenesis still remains unclear, and treatment is generally symptomatic. Recently, numerous therapeutic options, including growth factors, stem cells, and gene therapy, were investigated in hopes of enhancing the healing potency of the degenerative tendon. However, the majority of these research studies were conducted only on animal models or healthy human tenocytes. Despite some studies using pathological tenocytes, to the best of our knowledge there is currently no protocol describing how to obtain human degenerative tenocytes. The aim of this study is to describe a standard protocol for acquiring human degenerative tenocytes. Initially, the tendon tissue was harvested from a patient with lateral epicondylitis during surgery. Then biopsy samples were taken from the extensor carpi radialis brevis tendon corresponding to structural changes observed at the time of surgery. All of the harvested tendons appeared to be dull, gray, friable, and edematous, which made them visually distinct from the healthy ones. Tenocytes were cultured and used for experiments. Meanwhile, half of the harvested tissues were analyzed histologically, and it was shown that they shared the same key features of tendinopathy (angiofibroblastic dysplasia or hyperplasia). A secondary analysis by immunocytochemistry confirmed that the cultured cells were tenocytes with the majority of the cells having positive stains for mohawk and tenomodulin proteins. The qualities of the degenerative nature of tenocytes were then determined by comparing the cells with the healthy control using a proliferation assay or qRT-PCR. The degenerative tenocyte displayed a higher proliferation rate and similar gene expression patterns of tendinopathy that matched previous reports. Overall, this new protocol might provide a useful tool for future studies of tendinopathy.

Histological analyses revealed that the harvested tissue from lateral epicondylitis had the characteristics of a tendinopathic tendon.H&#38;E section of tendinopathy degenerative tendon revealed a disorganized collagen bundle with a loss of polarity and fine straight, strongly packed parallel fiber structures. Histological signs suggestive of degeneration such as higher cellularity and enlarged nuclei without the typical spindle shape were common in samples. Additionally, collagen bundles...

Watch this Scientific Journal Video about A Protocol to Acquire the Degenerative Tenocyte from Humans at JoVE.com

A Protocol to Acquire the Degenerative Tenocyte from Humans

In vitro use of degenerative tenocytes is essential when investigating the efficacy of novel treatment on tendinopathy. However, most research studies use only the animal model or a healthy tenocyte. We propose the following protocol to isolate human degenerative tenocytes during surgery.

Tendinopathy, a painful condition that develops in response to tendon degeneration, is on the rise in the developed world due to increasing physical ...

a-protocol-to-acquire-the-degenerative-tenocyte-from-humans

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

7.3K Views.  CHA University School of Medicine. In vitro use of degenerative tenocytes is essential when investigating the efficacy of novel treatment on tendinopathy. However, most research studies use only the animal model or a healthy tenocyte. We propose the following protocol to isolate human degenerative tenocytes during surgery.

Video: A Protocol to Acquire the Degenerative Tenocyte from Humans

The Trier Social Stress Test Protocol for Inducing Psychological Stress

This article demonstrates a psychological stress protocol for use in a laboratory setting. Protocols that allow researchers to study the biological pathways of the stress response in health and disease are fundamental to the progress of research in stress and anxiety.1 Although numerous protocols exist for inducing stress response in the laboratory, many neglect to provide a naturalistic context or to incorporate aspects of social and psychological stress. Of psychological stress protocols, meta-analysis suggests that the Trier Social Stress Test (TSST) is the most useful and appropriate standardized protocol for studies of stress hormone reactivity.2 In the original description of the TSST, researchers sought to design and evaluate a procedure capable of inducing a reliable stress response in the majority of healthy volunteers.3 These researchers found elevations in heart rate, blood pressure and several endocrine stress markers in response to the TSST (a psychological stressor) compared to a saline injection (a physical stressor).3 Although the TSST has been modified to meet the needs of various research groups, it generally consists of a waiting period upon arrival, anticipatory speech preparation, speech performance, and verbal arithmetic performance periods, followed by one or more recovery periods. The TSST requires participants to prepare and deliver a speech, and verbally respond to a challenging arithmetic problem in the presence of a socially evaluative audience.3 Social evaluation and uncontrollability have been identified as key components of stress induction by the TSST.4 In use for over a decade, the goal of the TSST is to systematically induce a stress response in order to measure differences in reactivity, anxiety and activation of the hypothalamic-pituitary-adrenal (HPA) or sympathetic-adrenal-medullary (SAM) axis during the task.1 Researchers generally assess changes in self-reported anxiety, physiological measures (e.g. heart rate), and/or neuroendocrine indices (e.g. the stress hormone cortisol) in response to the TSST. Many investigators have adopted salivary sampling for stress markers such as cortisol and alpha-amylase (a marker of autonomic nervous system activation) as an alternative to blood sampling to reduce the confounding stress of blood-collection techniques. In addition to changes experienced by an individual completing the TSST, researchers can compare changes between different treatment groups (e.g. clinical versus healthy control samples) or the effectiveness of stress-reducing interventions.1

This article describes a protocol for inducing psychological stress in participants, which enables researchers to measure psychological, physiological and neuroendocrine responses to stress within single participants or between groups.

This article demonstrates a psychological stress protocol for use in a laboratory setting.  Protocols that allow researchers to study the biological ...

Spectral Karyotyping to Study Chromosome Abnormalities in Humans and Mice with Polycystic Kidney Disease

Conventional method to identify and classify individual chromosomes depends on the unique banding pattern of each chromosome in a specific species being analyzed 1, 2. This classical banding technique, however, is not reliable in identifying complex chromosomal aberrations such as those associated with cancer. To overcome the limitations of the banding technique, Spectral Karyotyping (SKY) is introduced to provide much reliable information on chromosome abnormalities.
SKY is a multicolor fluorescence in-situ hybridization (FISH) technique to detect metaphase chromosomes with spectral microscope 3, 4. SKY has been proven to be a valuable tool for the cytogenetic analysis of a broad range of chromosome abnormalities associated with a large number of genetic diseases and malignancies 5, 6. SKY involves the use of multicolor fluorescently-labelled DNA probes prepared from the degenerate oligonucleotide primers by PCR. Thus, every chromosome has a unique spectral color after in-situ hybridization with probes, which are differentially labelled with a mixture of fluorescent dyes (Rhodamine, Texas Red, Cy5, FITC and Cy5.5). The probes used for SKY consist of up to 55 chromosome specific probes 7-10.
The procedure for SKY involves several steps (Figure 1). SKY requires the availability of cells with high mitotic index from normal or diseased tissue or blood. The chromosomes of a single cell from either a freshly isolated primary cell or a cell line are spread on a glass slide. This chromosome spread is labeled with a different combination of fluorescent dyes specific for each chromosome. For probe detection and image acquisition,the spectral imaging system consists of sagnac interferometer and a CCD camera. This allows measurement of the visible light spectrum emitted from the sample and to acquire a spectral image from individual chromosomes. HiSKY, the software used to analyze the results of the captured images, provides an easy identification of chromosome anomalies. The end result is a metaphase and a karyotype classification image, in which each pair of chromosomes has a distinct color (Figure 2). This allows easy identification of chromosome identities and translocations. For more details, please visit Applied Spectral Imaging website (<a href="http://www.spectral-imaging.com/" target="_blank">http://www.spectral-imaging.com/</a>).
SKY was recently used for an identification of chromosome segregation defects and chromosome abnormalities in humans and mice with Autosomal Dominant Polycystic Kidney Disease (ADPKD), a genetic disease characterized by dysfunction in primary cilia 11-13. Using this technique, we demonstrated the presence of abnormal chromosome segregation and chromosomal defects in ADPKD patients and mouse models 14. Further analyses using SKY not only allowed us to identify chromosomal number and identity, but also to accurately detect very complex chromosomal aberrations such as chromosome deletions and translocations (Figure 2).

Spectral Karyotyping (SKY) is an advanced cytogenetics technique to identify genomic and chromosomal aberrations. This technique takes advantage of chromosome painting probes, which allow classification of all chromosomes. SKY can also identify complex chromosome aberrations and segregation defects in mice and humans with various diseases, including polycystic kidney disease.

Conventional method to identify and classify individual chromosomes depends on the unique banding pattern of each chromosome in a specific species being ...

Heterotopic Renal Autotransplantation in a Porcine Model: A Step-by-Step Protocol

Kidney transplantation is the treatment of choice for patients suffering from end-stage renal disease. It offers better life expectancy and higher quality of life when compared to dialysis. Although the last few decades have seen major improvements in patient outcomes following kidney transplantation, the increasing shortage of available organs represents a severe problem worldwide. To expand the donor pool, marginal kidney grafts recovered from extended criteria donors (ECD) or donated after circulatory death (DCD) are now accepted for transplantation. To further improve the postoperative outcome of these marginal grafts, research must focus on new therapeutic approaches such as alternative preservation techniques, immunomodulation, gene transfer, and stem cell administration.
Experimental studies in animal models are the final step before newly developed techniques can be translated into clinical practice. Porcine kidney transplantation is an excellent model of human transplantation and allows investigation of novel approaches. The major advantage of the porcine model is its anatomical and physiological similarity to the human body, which facilitates the rapid translation of new findings to clinical trials. This article offers a surgical step-by-step protocol for an autotransplantation model and highlights key factors to ensure experimental success. Adequate pre- and postoperative housing, attentive anesthesia, and consistent surgical techniques result in favorable postoperative outcomes. Resection of the contralateral native kidney provides the opportunity to assess post-transplant graft function. The placement of venous and urinary catheters and the use of metabolic cages allow further detailed evaluation. For long-term follow-up studies and investigation of alternative graft preservation techniques, autotransplantation models are superior to allotransplantation models, as they avoid the confounding bias posed by rejection and immunosuppressive medication.

Porcine models of organ transplantation provide an important platform to study mechanisms of organ preservation. This article describes a heterotopic porcine renal autotransplantation model, which allows investigating new approaches to improve the outcome of transplantation using marginal kidney grafts.

Kidney transplantation is the treatment of choice for patients suffering from end-stage renal disease. It offers better life expectancy and higher quality ...

A Model to Simulate Clinically Relevant Hypoxia in Humans

In case of apnea, arterial partial pressure of oxygen (pO2) decreases, while partial pressure of carbon dioxide (pCO2) increases. To avoid damage to hypoxia sensitive organs such as the brain, compensatory circulatory mechanisms help to maintain an adequate oxygen supply. This is mainly achieved by increased cerebral blood flow. Intermittent hypoxia is a commonly seen phenomenon in patients with obstructive sleep apnea. Acute airway obstruction can also result in hypoxia and hypercapnia. Until now, no adequate model has been established to simulate these dynamics in humans. Previous investigations focusing on human hypoxia used inhaled hypoxic gas mixtures. However, the resulting hypoxia was combined with hyperventilation and is therefore more representative of high altitude environments than of apnea. Furthermore, the transferability of previously performed animal experiments to humans is limited and the pathophysiological background of apnea induced physiological changes is poorly understood. In this study, healthy human apneic divers were utilized to mimic clinically relevant hypoxia and hypercapnia during apnea. Additionally, pulse-oximetry and Near Infrared Spectroscopy (NIRS) were used to evaluate changes in cerebral and peripheral oxygen saturation before, during, and after apnea.

Hypoxia simulation in humans has usually been performed by inhaling hypoxic gas mixtures. For this study, apneic divers were used to simulate dynamic hypoxia in humans. Additionally, physiological changes in desaturation and re-saturation kinetics were evaluated with non-invasive tools such as Near-Infrared-Spectroscopy (NIRS) and peripheral oxygenation saturation (SpO2).

In case of apnea, arterial partial pressure of oxygen (pO2) decreases, while partial pressure of carbon dioxide (pCO2) increases. To avoid damage to ...

A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition

Limited evidence exists to precisely estimate efficacy and safety differences between parenteral nutrition (PN) prepared using olive-oil-based three-chamber bags (3CBs) and soybean-oil-based compounded bags (CoBs) in hospitalized adult patients. We designed a multicenter, randomized, prospective, open-label, noninferiority protocol to compare the efficacy, safety, and distribution of olive-oil-based 3CBs and soybean-oil-based CoB formulations in adult Chinese patients requiring PN during surgical intervention. Subjects were randomized to receive either one of the study treatments using an interactive voice or web-based recognition system in accordance with the randomization code. Randomization was further stratified based on the study site and surgical category. Both treatment groups received similar amounts of calories and protein. In addition, the two study treatments contained a similar composition of the amino-acid component. The only difference between the two PN formulations was the lipid constitution. The duration of administration of study treatments was a minimum of 5 days up to a maximum of 14 days after the surgical procedure. The primary efficacy endpoint was serum prealbumin levels on day 5 of the study. Noninferiority was proved if the anti-log of the lower bound of the 95% confidence interval (CI) of the treatment difference was at least 0.80. Other efficacy measures included treatment preparation time; duration to achieve tolerability of oral nutrition; associated infectious complications; length of hospitalization; and laboratory assessment of markers of nutrition, inflammation, metabolism, and oxidative stress. A total of 458 patients were enrolled in the study. The results showed that olive-oil-based 3CBs were non-inferior to soybean-based CoBs, besides being well tolerated. The infection rate was found to be significantly lower in the olive-oil-based 3CB group. Thus, this study may be used as a reference for future research on lipid emulsion and 3CBs.

Here, we present a protocol for a study comparing the efficacy, safety, and delivery of olive-oil-based 3CB and soybean-oil-based CoB formulations in adults requiring parenteral nutrition. The results revealed that olive-oil-based 3CBs is non-inferior and well tolerated compared to soybean formulations.

Limited evidence exists to precisely estimate efficacy and safety differences between parenteral nutrition (PN) prepared using olive-oil-based ...

Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic responses to acute exercise are predominantly influenced by the duration and intensity of the exercise regimen. As exercise is increasingly thought of as a therapeutic treatment and/or diagnostic tool, it is important that standardizable methodologies be utilized to understand the variability and to increase the reproducibility of exercise outputs and measurements of responses to such regimens. To that end, we describe two different cycling exercise regimens that yield different physiologic outputs. In a maximal exercise test, exercise intensity is continually increased with a greater workload resulting in an increasing cardiopulmonary and metabolic response (heart rate, stroke volume, ventilation, oxygen consumption and carbon dioxide production). In contrast, during endurance exercise tests, the demand is increased from that at rest, but is raised to a fixed submaximal exercise intensity resulting in a cardiopulmonary and metabolic response that typically plateaus. Along with the protocols, we provide suggestions on measuring physiologic outputs that include, but are not limited to, heart rate, slow and forced vital capacity, gas exchange metrics, and blood pressure to enable the comparison of exercise outputs between studies. Biospecimens can then be sampled to assess cellular, protein, and/or gene expression responses. Overall, this approach can be easily adapted into both short- and long-term effects of two distinct exercise regimens.

To assess the influence of exercise intensity on physiologic and biologic responses, two different exercise testing protocols were utilized. Methods outlining exercise testing on a cycle ergometer as an incremental maximal oxygen consumption test and endurance, steady state submaximal endurance test are described.

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic ...

A Proinflammatory, Degenerative Organ Culture Model to Simulate Early-Stage Intervertebral Disc Disease.

Symptomatic intervertebral disc (IVD) degeneration (IDD) is a major socioeconomic burden and is characterized by inflammation and tissue degradation. Due to the lack of causative therapies, there is an urgent need for innovative experimental organ culture models to study the mechanisms involved in the progression of the disease, find therapeutic targets, and reduce the need for animal models. We here present a novel, three-dimensional organ culture model protocol mimicking the proinflammatory and catabolic microenvironment, which is present during IDD. 
Initially, bovine caudal IVDs were dissected, cleaned, and cultured in the tissue culture medium. Dynamic physiologic or pathologic loading was applied in a custom-made bioreactor for 2 hours per day. IVDs were assigned to a control group (high glucose medium, physiological loading, phosphate-buffered saline injection) and a pathological group (low glucose medium, pathological loading, tumor necrosis factor-alpha injection) for four days. Gene expression analysis from collected nucleus pulposus cells of the IVDs and enzyme-linked immunosorbent assay of the conditioned organ culture media was performed. 
Our data revealed a higher expression of inflammatory markers and reduced disc heights after loading in the pathological group compared to the control group. This protocol is reliable to simulate IVD inflammation and degeneration and can be further expanded to broaden its application scope.

This protocol presents a novel experimental model of proinflammatory, degenerative bovine organ culture to simulate early-stage intervertebral disc degeneration.

Symptomatic intervertebral disc (IVD) degeneration (IDD) is a major socioeconomic burden and is characterized by inflammation and tissue degradation. Due ...

Retinal Pigment Epithelium Transplantation in a Non-human Primate Model for Degenerative Retinal Diseases

Retinal pigment epithelial (RPE) transplantation holds great promise for the treatment of inherited and acquired retinal degenerative diseases. These conditions include retinitis pigmentosa (RP) and advanced forms of age-related macular degeneration (AMD), such as geographic atrophy (GA). Together, these disorders represent a significant proportion of currently untreatable blindness globally. These unmet medical needs have generated heightened academic interest in developing methods of RPE replacement. Among the animal models commonly utilized for preclinical testing of therapeutics, the non-human primate (NHP) is the only animal model that has a macula. As it shares this anatomical similarity with the human eye, the NHP eye is an important and appropriate preclinical animal model for the development of advanced therapy medicinal products (ATMPs) such as RPE cell therapy.
This manuscript describes a method for the submacular transplantation of an RPE monolayer, cultured on a polyethylene terephthalate (PET) cell carrier, underneath the macula onto a surgically created RPE wound in immunosuppressed NHPs. The fovea-the central avascular portion of the macula-is the site of the greatest mechanical weakness during the transplantation. Foveal trauma will occur if the initial subretinal fluid injection generates an excessive force on the retina. Hence, slow injection under perfluorocarbon liquid (PFCL) vitreous tamponade is recommended with a dual-bore subretinal injection cannula at low intraocular pressure (IOP) settings to create a retinal bleb. 
Pretreatment with an intravitreal plasminogen injection to release parafoveal RPE-photoreceptor adhesions is also advised. These combined strategies can reduce the likelihood of foveal tears when compared to conventional techniques. The NHP is a key animal model in the preclinical phase of RPE cell therapy development. This protocol addresses the technical challenges associated with the delivery of RPE cellular therapy in the NHP eye.

The non-human primate (NHP) is an ideal model for studying human retinal cellular therapeutics due to the anatomical and genetic similarities. This manuscript describes a method for submacular transplantation of retinal pigment epithelial cells in the NHP eye and strategies to prevent intraoperative complications associated with macular manipulation.

Retinal pigment epithelial (RPE) transplantation holds great promise for the treatment of inherited and acquired retinal degenerative diseases. These ...

Quantification of Optic Nerve Cross Sectional Area on MRI: A Novel Protocol using Fiji Software

Optic nerve assessment is an important aspect of glaucoma diagnosis and follow-up. This project describes a protocol for a unified methodology of optic nerve cross-sectional assessment and quantification using 3 T MRI for image acquisition and ImageJ's Fiji software for image processing quantification. Image acquisition was performed using 3 T MRI, with proper instructions for the patient to ensure straight fixation during imaging. A T2-weighted fat suppressed sequence was used. A coronal cut taken 3 mm behind the globe and perpendicular to the optic nerve axis should be uploaded to the software. Using the threshold function, the white matter area of the optic nerve is selected and quantified, thus, eliminating inter-individual measurement bias. We also described the normal limits for the optic nerve cross-sectional area according to age, based on previously published literature. We used the described protocol to assess optic nerve of a suspected glaucoma patient. The optic nerve cross-sectional area was found to be within the normal limits, a finding further confirmed via optical coherence tomography of the optic nerve.

We provided a detailed protocol for a standardized method of optic nerve assessment and quantification using MRI, utilizing a widely available imaging sequence, and open access software for image analysis. Following this standardized protocol would provide meaningful data for comparison between different patients and different studies.

Optic nerve assessment is an important aspect of glaucoma diagnosis and follow-up. This project describes a protocol for a unified methodology of optic ...

A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement

High-Intensity Interval Training (HIIT) has emerged as an interesting time-efficient approach to increase exercise adherence and improve health. However, few studies have tested the efficiency of HIIT protocols in a &#34;real world&#34; setting, e.g., HIIT protocols designed for outdoor spaces without specialized equipment. This study presents a &#34;real world&#34; training protocol, named &#34;beep training&#34;, and compares the efficiency of a HIIT regiment versus a traditional long-duration Moderate-Intensity Continuous Training (MICT) regiment using this beep training protocol on VO2 max of overweight untrained men. Twenty-two subjects performed outdoor running with MICT (n = 11) or HIIT (n = 11). Cardiorespiratory fitness was assessed before and after training protocols using a metabolic analyzer. Both training protocols were performed 3 days a week for 8 weeks using the Beep Test results. The MICT group performed the exercise program at 60%-75% of the maximum speed of the 20 m shuttle test (Vmax) and with a progression of the distance of 3,500-5,000 m. The HIIT group performed the interval exercise with 7-10 bouts of 200 m at 85%-100% of the maximum speed of the 20 m shuttle test (Vmax), interspersed with 1 min of passive recovery. Although the HIIT group presented a significantly lower training volume than the MICT group (p &#60; 0.05) after 8 weeks of beep training, HIIT was superior to MICT in improving VO2 max (MICT: ~4.1%; HIIT: ~7.3%; p &#60; 0.05). The &#34;real world&#34; HIIT regiment based on beep training protocol is a time-efficient, low-cost, and easy-to-implement protocol for overweight untrained men.

This study presents a low-cost and easy-to-implement "real world" high-intensity interval training (HIIT) protocol for scientific research and discusses its efficiency for cardiorespiratory fitness.

High-Intensity Interval Training (HIIT) has emerged as an interesting time-efficient approach to increase exercise adherence and improve health. However, ...