Name: a proinflammatory, degenerative organ culture model to simulate early-stage intervertebral disc disease.
Uploaded: 2021-02-14T13:30:00
Description: Watch this Scientific Journal Video about A Proinflammatory, Degenerative Organ Culture Model to Simulate Early-Stage Intervertebral Disc Disease. at JoVE.com

This work was supported by AO Foundation and AOSpine International. Babak Saravi received fellowship support from the German Spine Foundation and the German Osteoarthritis Foundation. Gernot Lang was supported by the Berta-Ottenstein-Programme for Advanced Clinician Scientists, Faculty of Medicine, University of Freiburg, Germany.

Experiments were performed using bovine tails obtained from local abattoirs. The biological materials used in the current study are taken from the food chain and require no ethical approval in Swiss and European law.
1. Dissection of the bovine intervertebral disc
<ol>
	<li>Rinse the whole tail thoroughly with tap water to remove dirt and hair on the surface. 
	NOTE: With intact, distal ends, a maximum of 9 IVDs (coccygeal 1-9) per tail can be used for the experiments depending on the d...

<ol>
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S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low+back+pain.">Low back pain.</a> Nature Reviews Disease Primers. 4 (1), 52 (2018).</li><li>Khan, A. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inflammatory+biomarkers+of+low+back+pain+and+disc+degeneration:+a+review:+Biomarkers+of+disc+degeneration+and+back+pain.">Inflammatory biomarkers of low back pain and disc degeneration: a review: Biomarkers of disc degeneration and back pain.</a> Annals of the New York Academy of Sciences. 1410 (1), 68-84 (2017).</li><li>Kim, H. S., Wu, P. H., Jang, I. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lumbar+Degenerative+Disease+Part+1:+Anatomy+and+Pathophysiology+of+Intervertebral+Discogenic+Pain+and+Radiofrequency+Ablation+of+Basivertebral+and+Sinuvertebral+Nerve+Treatment+for+Chronic+Discogenic+Back+Pain:+A+Prospective+Case+Series+and+Review+of+Literature.">Lumbar Degenerative Disease Part 1: Anatomy and Pathophysiology of Intervertebral Discogenic Pain and Radiofrequency Ablation of Basivertebral and Sinuvertebral Nerve Treatment for Chronic Discogenic Back Pain: A Prospective Case Series and Review of Literature.</a> International Journal of Molecular Sciences. 21 (4), 1483 (2020).</li><li>Adams, M. A., Roughley, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+is+Intervertebral+Disc+Degeneration,+and+What+Causes+It.">What is Intervertebral Disc Degeneration, and What Causes It.</a> Spine. 31 (18), 2151-2161 (2006).</li><li>Wu, P. H., Kim, H. S., Jang, I. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intervertebral+Disc+Diseases+Part+2:+A+Review+of+the+Current+Diagnostic+and+Treatment+Strategies+for+Intervertebral+Disc+Disease.">Intervertebral Disc Diseases Part 2: A Review of the Current Diagnostic and Treatment Strategies for Intervertebral Disc Disease.</a> International Journal of Molecular Sciences. 21 (6), 2135 (2020).</li><li>Lurie, J. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgical+Versus+Nonoperative+Treatment+for+Lumbar+Disc+Herniation:+Eight-Year+Results+for+the+Spine+Patient+Outcomes+Research+Trial.">Surgical Versus Nonoperative Treatment for Lumbar Disc Herniation: Eight-Year Results for the Spine Patient Outcomes Research Trial.</a> Spine. 39 (1), 3-16 (2014).</li><li>Risbud, M. V., Shapiro, I. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+cytokines+in+intervertebral+disc+degeneration:+pain+and+disc+content.">Role of cytokines in intervertebral disc degeneration: pain and disc content.</a> Nature Reviews Rheumatology. 10 (1), 44-56 (2014).</li><li>Ponnappan, R. 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T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+whole+organ+culture+model+for+intervertebral+disc+disease.">Development of a whole organ culture model for intervertebral disc disease.</a> Journal of Orthopaedic Translation. 5, 1-8 (2016).</li><li>Li, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preclinical+ex-vivo+Testing+of+Anti-inflammatory+Drugs+in+a+Bovine+Intervertebral+Degenerative+Disc+Model.">Preclinical ex-vivo Testing of Anti-inflammatory Drugs in a Bovine Intervertebral Degenerative Disc Model.</a> Frontiers in Bioengineering and Biotechnology. 8, 583 (2020).</li><li>Li, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+an+ex+vivo+cavity+model+to+study+repair+strategies+in+loaded+intervertebral+discs.">Development of an ex vivo cavity model to study repair strategies in loaded intervertebral discs.</a> European Spine Journal. 25 (9), 2898-2908 (2016).</li><li>Kazezian, Z., Li, Z., Alini, M., Grad, S., Pandit, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Injectable+hyaluronic+acid+down-regulates+interferon+signaling+molecules,+IGFBP3+and+IFIT3+in+the+bovine+intervertebral+disc.">Injectable hyaluronic acid down-regulates interferon signaling molecules, IGFBP3 and IFIT3 in the bovine intervertebral disc.</a> Acta Biomaterialia. 52, 118-129 (2017).</li><li>Caprez, S., Menzel, U., Li, Z., Grad, S., Alini, M., Peroglio, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+high-quality+RNA+from+intervertebral+disc+tissue+via+pronase+predigestion+and+tissue+pulverization.">Isolation of high-quality RNA from intervertebral disc tissue via pronase predigestion and tissue pulverization.</a> JOR Spine. 1 (2), 1017 (2018).</li><li>Lopa, S., Ceriani, C., Cecchinato, R., Zagra, L., Moretti, M., Colombini, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stability+of+housekeeping+genes+in+human+intervertebral+disc,+endplate+and+articular+cartilage+cells+in+multiple+conditions+for+reliable+transcriptional+analysis.">Stability of housekeeping genes in human intervertebral disc, endplate and articular cartilage cells in multiple conditions for reliable transcriptional analysis.</a> European Cells &amp; Materials. 31, 395-406 (2016).</li><li>Lang, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+intervertebral+disc+whole+organ+culture+system+to+investigate+proinflammatory+and+degenerative+disc+disease+condition.">An intervertebral disc whole organ culture system to investigate proinflammatory and degenerative disc disease condition.</a> Journal of Tissue Engineering and Regenerative Medicine. 12 (4), 2051-2061 (2018).</li><li>Du, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proinflammatory+intervertebral+disc+cell+and+organ+culture+models+induced+by+tumor+necrosis+factor+alpha.">Proinflammatory intervertebral disc cell and organ culture models induced by tumor necrosis factor alpha.</a> JOR Spine. 3, 1104 (2020).</li><li>Purmessur, D., Walter, B. A., Roughley, P. J., Laudier, D. M., Hecht, A. C., Iatridis, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+role+for+TNF&#945;+in+intervertebral+disc+degeneration:+A+non-recoverable+catabolic+shift.">A role for TNF&#945; in intervertebral disc degeneration: A non-recoverable catabolic shift.</a> Biochemical and Biophysical Research Communications. 433 (1), 151-156 (2013).</li><li>Walter, B. A., Likhitpanichkul, M., Illien-Junger, S., Roughley, P. J., Hecht, A. C., Iatridis, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TNF&#945;+Transport+Induced+by+Dynamic+Loading+Alters+Biomechanics+of+Intact+Intervertebral+Discs.">TNF&#945; Transport Induced by Dynamic Loading Alters Biomechanics of Intact Intervertebral Discs.</a> PLOS One. 10 (3), 0118358 (2015).</li><li>Gullbrand, S. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+large+animal+model+that+recapitulates+the+spectrum+of+human+intervertebral+disc+degeneration.">A large animal model that recapitulates the spectrum of human intervertebral disc degeneration.</a> Osteoarthritis and Cartilage. 25 (1), 146-156 (2017).</li><li>Willems, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Safety+of+intradiscal+injection+and+biocompatibility+of+polyester+amide+microspheres+in+a+canine+model+predisposed+to+intervertebral+disc+degeneration:+intradiscal+application+of+pea+microspheres.">Safety of intradiscal injection and biocompatibility of polyester amide microspheres in a canine model predisposed to intervertebral disc degeneration: intradiscal application of pea microspheres.</a> Journal of Biomedical Materials Research Part B: Applied Biomaterials. 105 (4), 707-714 (2017).</li><li>Michalek, A. J., Buckley, M. R., Bonassar, L. J., Cohen, I., Iatridis, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+needle+puncture+injury+on+microscale+shear+strain+in+the+intervertebral+disc+annulus+fibrosus.">The effects of needle puncture injury on microscale shear strain in the intervertebral disc annulus fibrosus.</a> The Spine Journal. 10 (12), 1098-1105 (2010).</li><li>Illien-J&#252;nger, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+combined+effects+of+limited+nutrition+and+high-frequency+loading+on+intervertebral+discs+with+endplates.">The combined effects of limited nutrition and high-frequency loading on intervertebral discs with endplates.</a> Spine. 35 (19), 1744-1752 (2010).</li><li>Gantenbein, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organ+culture+bioreactors--platforms+to+study+human+intervertebral+disc+degeneration+and+regenerative+therapy.">Organ culture bioreactors--platforms to study human intervertebral disc degeneration and regenerative therapy.</a> Current Stem Cell Research &amp; Therapy. 10 (4), 339-352 (2015).</li><li>Boubriak, O. A., Watson, N., Sivan, S. S., Stubbens, N., Urban, J. P. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+regulating+viable+cell+density+in+the+intervertebral+disc:+blood+supply+in+relation+to+disc+height.">Factors regulating viable cell density in the intervertebral disc: blood supply in relation to disc height.</a> Journal of Anatomy. 222 (3), 341-348 (2013).</li><li>Maroudas, A., Stockwell, R. A., Nachemson, A., Urban, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Factors+involved+in+the+nutrition+of+the+human+lumbar+intervertebral+disc:+cellularity+and+diffusion+of+glucose+in+vitro.">Factors involved in the nutrition of the human lumbar intervertebral disc: cellularity and diffusion of glucose in vitro.</a> Journal of Anatomy. 120, 113-130 (1975).</li><li>Beckstein, J. 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J., Davidson, E. N. B., vander Kraan, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phenotypic+marker+genes+distinguish+inner+and+outer+annulus+fibrosus+from+nucleus+pulposus+tissue+in+the+bovine+intervertebral+disc.">Phenotypic marker genes distinguish inner and outer annulus fibrosus from nucleus pulposus tissue in the bovine intervertebral disc.</a> Osteoarthritis and Cartilage. 25, 402 (2017).</li><li>Du, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+cell+phenotype+induction+with+TGF-&#946;1+and+collagen-polyurethane+scaffold+for+annulus+fibrosus+rupture+repair.">Functional cell phenotype induction with TGF-&#946;1 and collagen-polyurethane scaffold for annulus fibrosus rupture repair.</a> European Cells &amp; Materials. 39, 1-17 (2020).</li><li>Risbud, M. 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We here provided a detailed protocol to simulate degenerative and inflammatory IVDD. This protocol can be applied for detailed examinations of inflammatory pathways leading to the destructive effects on the disc. Moreover, the protocol can help to determine promising therapeutic targets involved in the progression of the disease.
We recently showed that human recombinant TNF-&#945; could induce inflammation in both bovine and human NP cells21, which is in accordance wit...

Low back pain (LBP) can affect individuals of all ages and is a leading cause for disability worldwide1,2,3. The total cost associated with LBP exceeds $100 billion per year4,5. Symptomatic intervertebral disc (IVD) degeneration (IDD), a condition characterized by inflammation and tissue degradation, is a major cause of LBP6,7. Specifically, IDD is characterized by a gradually evolving breakdown of the IVD&#39;s extracellular matrix (ECM), induced and triggered by multiple factors that lead to an accelerated pathology, neurological disorders, and eventually disability. Furthermore, IDD is associated with the release of proinflammatory cytokines, altered spine biomechanics, angiogenesis, and nerve ingrowth, which increases pain sensation, altogether causing chronic LBP (active discopathy)6,8. To date, treatment options include discectomy and subsequent fusion of the adjacent vertebrae, implantation of an IVD prosthesis, or non-surgical approaches, such as non-steroidal anti-inflammatory drugs, opioids, and muscle relaxants for patients with IDD9. Both current standard therapeutic options, surgical and non-surgical, are only partly effective and fail to address the underlying biological problem9,10. Early-stage degenerative disc disease is characterized by an initial inflammatory tissue response, especially an increase in tumor necrosis factor-alpha (TNF-alpha) expression11. These early disc changes primarily occur at the cellular level without disrupting the disc architecture and could previously be mimicked by nutritional deficiency under pro-inflammatory conditions12. Therefore, precise simulation of the in vivo situation to investigate these degeneration mechanisms and find suitable therapeutic targets is crucial. Additionally, to these simulations of molecular properties, the mechanical loading environment of the discs plays a key role in pathological and physiological changes of IVD. Consequently, combining these approaches would bring us one step forward to mimic the complex microenvironment of IVDs in vivo. There are currently no studies considering the aspect of dynamic loading along with the pro-inflammatory and nutritional setting to the best of our knowledge.
Although large animal models allow the investigation of potential relevant in vivo interactions, they are costly and work intensive. Moreover, as the use of animal models in research has long been a matter of controversy, the reduction of the number of animals needed to answer important research questions is of great interest. Finally, there is currently no ideal animal model to mimic IDD in IVD research13,14. Therefore, it is necessary to establish a cost-effective and reliable replacement, such as an organ culture model to simulate IDD and associated inflammatory and degenerative processes. Recently, the application of the present protocol on the establishment of a proinflammatory and degenerative organ culture model to simulate early-stage intervertebral disc disease allowed us to investigate the effect of anti-inflammatory drugs in the IDD organ culture15.
Here, we describe how to obtain bovine intervertebral discs and induce the state of early-stage IDD via a catabolic and proinflammatory microenvironment caused by direct intradiscal injection of tumor necrosis factor-alpha (TNF-&#945;) and degenerative loading in a bioreactor under low nutritive medium conditions. Figure 1 illustrates the experimental model and shows the bioreactor used to simulate degenerative and physiological loading conditions.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/62100/62100fig01.jpg" /> 
Figure 1: Illustration of the experimental setup. A: bovine tail; B: dissected bovine intervertebral discs; C: transfer of the disc to a well-plate with culture medium; D: loading the simulation in a bioreactor; E: intradiscal injection technique; F: IVD after injection of PBS/trypan blue dye to reveal distribution. IDD: intervertebral disc degeneration. <a href="https://www.jove.com/files/ftp_upload/62100/62100fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1-Bromo-3-chloropropane(BCP)</td>
			<td>Sigma-Aldrich, St. Louis, USA</td>
			<td>B9673</td>
			<td></td>
		</tr>
		<tr>
			<td>Ascorbate-2-phosphate</td>
			<td>Sigma-Aldrich, St. Louis, USA</td>
			<td>A8960</td>
			<td></td>
		</tr>
		<tr>
			<td>Band saw</td>
			<td>Exakt Apparatebau, Norderstedt, Germany</td>
			<td>model 30/833</td>
			<td></td>
		</tr>
		<tr>
			<td>Betadine</td>
			<td>Munndipharma, Frankfurt, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine IL-8 Do.it-Yourself ELISA</td>
			<td>Kingfisher Biotech, St. Paul, USA</td>
			<td>DIY1028B-003</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning ITS Premix</td>
			<td>Corning Inc., New York, USA</td>
			<td>354350</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM high glucose</td>
			<td>Gibco by life technologies, Carlsbad, USA</td>
			<td>10741574</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM low glucose</td>
			<td>Gibco by life technologies, Carlsbad, USA</td>
			<td>11564446</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol for molecular biology</td>
			<td>Sigma-Aldrich, St. Louis, USA</td>
			<td>09-0851</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Gibco by life technologies, Carlsbad, USA</td>
			<td>A4766801</td>
			<td></td>
		</tr>
		<tr>
			<td>Non-essential amino acid solution</td>
			<td>Gibco by life technologies, Carlsbad, USA</td>
			<td>11140050</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin(P/S)</td>
			<td>gibco by life technologies, Carlsbad, USA</td>
			<td>11548876</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate Buffer Solution, tablet</td>
			<td>Sigma-Aldrich, St. Louis, USA</td>
			<td>P4417</td>
			<td></td>
		</tr>
		<tr>
			<td>Pronase</td>
			<td>Sigma-Aldrich, St. Louis, USA</td>
			<td>10165921001</td>
			<td></td>
		</tr>
		<tr>
			<td>Primocin</td>
			<td>InvivoGen, Sandiego, USA</td>
			<td>ant-pm-05</td>
			<td></td>
		</tr>
		<tr>
			<td>Pulsavac Jet Lavage System</td>
			<td>Zimmer, IN,USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>TissueLyser II</td>
			<td>Quiagen, Venlo, Netherlands</td>
			<td>85300</td>
			<td></td>
		</tr>
		<tr>
			<td>Streptavidinn-HRP</td>
			<td>Kingfisher Biotech, St. Paul, USA</td>
			<td>AR0068-001</td>
			<td></td>
		</tr>
		<tr>
			<td>Superscript VILO</td>
			<td>Invitrogen by life Technologies, Carlsbad, USA</td>
			<td>10704274</td>
			<td></td>
		</tr>
		<tr>
			<td>cDNA Synthesis Kit</td>
			<td>Applied Biosystems by life technologies</td>
			<td>10400745</td>
			<td></td>
		</tr>
		<tr>
			<td>TaqMan Universal Master Mix</td>
			<td>Applied Biosystems by life technologies</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>TNF-alpha, recombinant human protein</td>
			<td>R&#38;D systems, Minnesota, USA</td>
			<td>210-TA-005</td>
			<td></td>
		</tr>
		<tr>
			<td>TRI Reagent</td>
			<td>Molecular Research Center, Cincinnati, USA</td>
			<td>TR 118</td>
			<td></td>
		</tr>
		<tr>
			<td>Tris-EDTA buffer solution</td>
			<td>sigma-Aldrich, St. Louis, USA</td>
			<td>93283</td>
			<td></td>
		</tr>
		<tr>
			<td>Gene bIL-6</td>
			<td>Applied Biosystems by life technologies</td>
			<td>Custom made probes</td>
			<td>Primer fw (5&#8242;&#8211;3&#8242;) TTC CAA AAA TGG AGG AAA AGG A 
			Primer rev (5&#8242;&#8211;3&#8242;) TCC AGA AGA CCA GCA GTG GTT 
			Probe (5&#8242;FAM/3&#8242;TAMRA) CTT CCA ATC TGG GTT CAA TCA GGC GATT</td>
		</tr>
		<tr>
			<td>Gene bIL8</td>
			<td>Applied Biosystems by life technologies</td>
			<td>Bt03211906_m1</td>
			<td></td>
		</tr>
		<tr>
			<td>Gene bTNF-alpha</td>
			<td>Applied Biosystems by life technologies</td>
			<td>Custom made probes</td>
			<td>Primer fw (5&#8242;&#8211;3&#8242;) CCT CTT CTC AAG CCT CAA GTA ACA A 
			Primer rev (5&#8242;&#8211;3&#8242;) GAG CTG CCC CGG AGA GTT 
			Probe (5&#8242;FAM/3&#8242;TAMRA) ATG TCG GCT ACA ACG TGG GCT ACC G</td>
		</tr>
		<tr>
			<td>GENE bIL1beta</td>
			<td>Applied Biosystems by life technologies</td>
			<td>Custom made probes</td>
			<td>Primer fw (5&#8242;&#8211;3&#8242;) TTA CTA CAG TGA CGA GAA TGA GCT GTT 
			Primer rev (5&#8242;&#8211;3&#8242;) GGT CCA GGT GTT GGA TGC A 
			Probe (5&#8242;FAM/3&#8242;TAMRA) CTC TTC ATC TGT TTA GGG TCA TCA GCC TCA A</td>
		</tr>
		<tr>
			<td>RPLP0</td>
			<td>Applied Biosystems by life technologies</td>
			<td>Bt03218086_m1</td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

Degenerative loading in low glucose medium combined with TNF-&#945; injection caused a significant increase of the gene expression of proinflammatory markers interleukin 6 (IL-6) and interleukin 8 (IL-8) compared to the physiological control group in NP cells after 4 days of culture (Figure 2). In contrast, we did not observe significant changes for the proinflammatory genes interleukin 1&#946; (IL-1&#946;) and TNF-&#945; in NP cells (data not shown). Furthermore, degenerative culture condit...

Watch this Scientific Journal Video about A Proinflammatory, Degenerative Organ Culture Model to Simulate Early-Stage Intervertebral Disc Disease. at JoVE.com

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

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 ...

The protocol aims to simulate in vivo conditions of intervertebral disc degeneration to investigate its pathophysiology without the need for animal models. Compared with in vitro cell culture, the bioreactor organ culture technique maintains the cells in their native biological and biomechanical microenvironment in addition to the supply of a controllable and reproducible culture condition. Start with rinsing the entire bovine tail thoroughly with tap water to remove dirt and hair on the surface, then immerse the tail in 1%betadine solution for 10 minutes to disinfect the surface.Use a scalpel number 20 to remove the soft tissue from the caudal spine to facilitate the identification of the intervertebral discs, or IVDs. Remove the spinous and transverse processes of the vertebrae with a bone removal plier. Cut transversely with bone pliers through the middle of each vertebral body to obtain individual motion segments, then put the collected motion segments in a Petri dish with a gauze wetted in Ringer's solution.Locate the IVD in vertebrae by moving the motion segments gently, then identify the location of the growth plate by touching and finding the convex side of the bony end plate. Cool the blade of the bandsaw with Ringer's solution and use it to make two parallel cuts in the growth plate of the IVDs, one on each side. Transfer the IVDs to a clean Petri dish with clean gauze wetted with Ringer's solution.Scrape off the vertebral body and growth plate using the scalpel blade, leaving the end plate intact. Position the two surfaces flat and parallel for the loading procedure and transfer scraped IVDs to a fresh Petri dish with gauze wetted with Ringer's solution. Measure the disc height and diameter with a caliper, then clean the blood clots in the vertebrae bone with Ringer's solution using a jet lavage system.Disinfect IVDs in PBS and 10%penicillin streptomycin with shaking for 15 minutes. Rinse off the high concentration antibiotics with PBS and 1%penicillin streptomycin. Transfer discs to IVD chambers containing five milliliters of IVD culture medium and place them in the bioreactor system with an incubator at 37 degrees Celsius with 85%humidity and 5%carbon dioxide.Culture the disks for four days within a bioreactor system by maintaining different loading conditions according to the experimental groups. In the physiological control group, culture the IVDs with high glucose medium using a loading protocol of 0.02 to 0.2 megapascals and 0.2 hertz for two hours per day. In the pathological group, culture the IVDs with low glucose medium using a loading protocol of 0.32 to 0.5 megapascals and five hertz for two hours per day.Between the loading procedures, place the IVDs in six-well plates with seven milliliters of IVD culture medium for free swelling recovery. Measure the disc height daily with a caliper after the free swelling period and after dynamic loading for the experimental duration. After the first dynamic loading cycle on day one, directly place the IVDs in a Petri dish in a vertical position and stabilize them with a tweezer.Inject recombinant TNF-alpha with a 30-gauge insulin needle slowly at a speed of approximately 70 microliters per minute into the IVDs of the pathological group. After injecting, pull the syringe halfway back and pull the plunger to create a vacuum that prevents the injected solution from leaking, then remove the syringe completely from the IVD. Degenerative loading combined with limited nutrition supply and a TNF-alpha injection caused a significant increase in the gene expression of pro-inflammatory markers interleukin six and interleukin eight in NP tissue after four days of culture.The interleukin eight protein release into the conditioned medium showed a marked increase in the pathological group on day two and day four. Disc height reduction after loading was higher in the pathological group compared to the physiological group, and the differences were more pronounced after days two and three compared with day one, indicating a progressive effect of the degenerative and inflammatory conditions. A standardized dissection technique is important for reproducible IVD whole-organ culture models.A bioreactor is required to apply physiological and degenerative loadings on IVDs to simulate various in vivo biomechanical conditions. This technique can be applied on human IVD explants which is of high clinical relevance. It's a novel preclinical model for developing effective treatments on early stage disc degeneration.

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Research

JoVE Journal

Medicine

Murine Corneal Transplantation: A Model to Study the Most Common Form of Solid Organ Transplantation

Corneal transplantation is the most common form of organ transplantation in the United States with between 45,000 and 55,000 procedures performed each year. While several animal models exist for this procedure and mice are the species that is most commonly used. The reasons for using mice are the relative cost of using this species, the existence of many genetically defined strains that allow for the study of immune responses, and the existence of an extensive array of reagents that can be used to further define responses in this species. This model has been used to define factors in the cornea that are responsible for the relative immune privilege status of this tissue that enables corneal allografts to survive acute rejection in the absence of immunosuppressive therapy. It has also been used to define those factors that are most important in rejection of such allografts. Consequently, much of what we know concerning mechanisms of both corneal allograft acceptance and rejection are due to studies using a murine model of corneal transplantation. In addition to describing a model for acute corneal allograft rejection, we also present for the first time a model of late-term corneal allograft rejection.

Mice have been used as a model for studying many forms of transplantation, including corneal transplantation. We describe in this report a murine model for both acute and late-term corneal transplantation.

Corneal transplantation is the most common form of organ transplantation in the United States with between 45,000 and 55,000 procedures performed each ...

Method of Isolated Ex Vivo Lung Perfusion in a Rat Model: Lessons Learned from Developing a Rat EVLP Program

The number of acceptable donor lungs available for lung transplantation is severely limited due to poor quality. Ex-Vivo Lung Perfusion (EVLP) has allowed lung transplantation in humans to become more readily available by enabling the ability to assess organs and expand the donor pool. As this technology expands and improves, the ability to potentially evaluate and improve the quality of substandard lungs prior to transplant is a critical need. In order to more rigorously evaluate these approaches, a reproducible animal model needs to be established that would allow for testing of improved techniques and management of the donated lungs as well as to the lung-transplant recipient. In addition, an EVLP animal model of associated pathologies, e.g., ventilation induced lung injury (VILI), would provide a novel method to evaluate treatments for these pathologies. Here, we describe the development of a rat EVLP lung program and refinements to this method that allow for a reproducible model for future expansion. We also describe the application of this EVLP system to model VILI in rat lungs. The goal is to provide the research community with key information and &#8220;pearls of wisdom&#8221;/techniques that arose from trial and error and are critical to establishing an EVLP system that is robust and reproducible.

Method of Isolated Ex Vivo Lung Perfusion in a Rat Model: Lessons Learned from Developing a Rat EVLP Program

Ex-Vivo Lung Perfusion (EVLP) has allowed lung transplantation in humans to become more readily available by enabling the ability to assess organs and expand the donor pool. Here, we describe the development of a rat EVLP program and refinements that allow for a reproducible model for future expansion.

The number of acceptable donor lungs available for lung transplantation is severely limited due to poor quality. Ex-Vivo Lung Perfusion (EVLP) has allowed ...

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 ...

Ovine Lumbar Intervertebral Disc Degeneration Model Utilizing a Lateral Retroperitoneal Drill Bit Injury

Intervertebral disc degeneration is a significant contributor to the development of back pain and the leading cause of disability worldwide. Numerous animal models of intervertebral disc degeneration have been developed. The ideal animal model should closely mimic the human intervertebral disc with regard to morphology, biomechanical properties and the absence of notochordal cells. The sheep lumbar intervertebral disc model fulfils these criteria. We present an ovine model of intervertebral disc degeneration utilizing a drill bit injury through a lateral retroperitoneal approach. The lateral approach significantly reduces the incision and potential morbidity associated with the traditional anterior approach to the ovine spine. Utilization of a drill-bit method of injury affords the ability to produce a consistent and reproducible injury, of precise dimensions, that initiates a consistent degree of intervertebral disc degeneration. The focal nature of the annular and nucleus pulposus defect more closely mimics the clinical condition of focal intervertebral disc herniation. Sheep recover rapidly following this procedure and are typically mobile and eating within the hour. Intervertebral disc degeneration ensues and sheep undergo necropsy and subsequent analysis at periods from eight weeks. We believe that the drill bit injury model of intervertebral disc degeneration offers advantages over more conventional annular injury models.

Intervertebral disc degeneration is a significant contributor to back pain and a leading cause of disability worldwide. Numerous animal models of intervertebral disc degeneration exist. We demonstrate an ovine model of intervertebral disc degeneration, utilizing a drill bit, which achieves a consistent disc injury and reproducible level of disc degeneration.

Intervertebral disc degeneration is a significant contributor to the development of back pain and the leading cause of disability worldwide. Numerous ...

A Cell Culture Model of Resistance Arteries

The myoendothelial junction (MEJ), a unique signaling microdomain in small diameter resistance arteries, exhibits localization of specific proteins and signaling processes that can control vascular tone and blood pressure. As it is a projection from either the endothelial or smooth muscle cell, and due to its small size (on average, an area of ~1 &#181;m2), the MEJ is difficult to study in isolation. However, we have developed a cell culture model called the vascular cell co-culture (VCCC) that allows for in vitro MEJ formation, endothelial cell polarization, and dissection of signaling proteins and processes in the vascular wall of resistance arteries. The VCCC has a multitude of applications and can be adapted to suit different cell types. The model consists of two cell types grown on opposite sides of a filter with 0.4 &#181;m pores in which the in vitro MEJs can form. Here we describe how to create the VCCC via plating of cells and isolation of endothelial, MEJ, and smooth muscle fractions, which can then be used for protein isolation or activity assays. The filter with intact cell layers can be fixed, embedded, and sectioned for immunofluorescent analysis. Importantly, many of the discoveries from this model have been confirmed using intact resistance arteries, underscoring its physiological relevance.

A cell culture model of resistance arteries is described, allowing for the dissection of signaling pathways in endothelium, smooth muscle, or between endothelium and smooth muscle (the myoendothelial junction). The selective application of agonists or protein isolation, electron microscopy, or immunofluorescence can be utilized using this cell culture model.

The myoendothelial junction (MEJ), a unique signaling microdomain in small diameter resistance arteries, exhibits localization of specific proteins and ...

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.

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 ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

Ex Vivo Corneal Organ Culture Model for Wound Healing Studies

The cornea has been used extensively as a model system to study wound healing. The ability to generate and utilize primary mammalian cells in two dimensional (2D) and three dimensional (3D) culture has generated a wealth of information not only about corneal biology but also about wound healing, myofibroblast biology, and scarring in general. The goal of the protocol is an assay system for quantifying myofibroblast development, which characterizes scarring. We demonstrate a corneal organ culture ex vivo model using pig eyes. In this anterior keratectomy wound, corneas still in the globe are wounded with a circular blade called a trephine. A plug of approximately 1/3 of the anterior cornea is removed including the epithelium, the basement membrane, and the anterior part of the stroma. After wounding, corneas are cut from the globe, mounted on a collagen/agar base, and cultured for two weeks in supplemented-serum free medium with stabilized vitamin C to augment cell proliferation and extracellular matrix secretion by resident fibroblasts. Activation of myofibroblasts in the anterior stroma is evident in the healed cornea. This model can be used to assay wound closure, the development of myofibroblasts and fibrotic markers, and for toxicology studies. In addition, the effects of small molecule inhibitors as well as lipid-mediated siRNA transfection for gene knockdown can be tested in this system.

A protocol for an ex vivo corneal organ culture model useful for wound healing studies is described. This model system can be used to assess the effects of agents to promote regenerative healing or drug toxicity in an organized 3D multicellular environment.

The cornea has been used extensively as a model system to study wound healing. The ability to generate and utilize primary mammalian cells in two ...

A Porcine Corneal Endothelial Organ Culture Model Using Split Corneal Buttons

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for experimental investigations as they are normally needed for transplantation. Endothelial cell cultures often do not translate well to in vivo situations. Due to the biostructural characteristics of non-human corneas, stromal swelling during cultivation induces substantial corneal endothelial cell loss, which makes it difficult to perform cultivation for an extended period of time. Deswelling agents such as dextran are used to counteract this response. However, they also cause significant endothelial cell loss. Therefore, an ex vivo organ culture model not requiring deswelling agents was established. Pig eyes from a local slaughterhouse were used to prepare split corneal buttons. After partial corneal trephination, the outer layers of the cornea (epithelium, bowman layer, parts of the stroma) were removed. This significantly reduces corneal endothelial cell loss induced by massive stromal swelling and Descemet&#39;s membrane folding throughout longer cultivation periods and improves general preservation of the endothelial cell layer. Subsequent complete corneal trephination was followed by the removal of the split corneal button from the remaining eye bulb and cultivation. Endothelial cell density was assessed at follow-up times of up to 15 days after preparation (i.e., days 1, 8, 15) using light microscopy. The preparation technique used allows a better preservation of the endothelial cell layer enabled by less stromal tissue swelling, which results in slow and linear decline rates in split corneal buttons comparable to human donor corneas. As this standardized organo-typically cultivated research model for the first time allows a stable cultivation for at least two weeks, it is a valuable alternative to human donor corneas for future investigations of various external factors with regards to their effects on the corneal endothelium.

Here, a step-by-step protocol for the preparation and cultivation of porcine split corneal buttons is presented. As this organo-typically cultivated organ culture model shows cell death rates within 15 days, comparable to human donor corneas, it represents the first model allowing long-term cultivation of non-human corneas without adding toxic dextran.

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for ...

A Rat Lung Transplantation Model of Warm Ischemia/Reperfusion Injury: Optimizations to Improve Outcomes

From our experience with rat lung transplantation, we have found several areas for improvement. Information in the existing literature regarding methods for choosing appropriate cuff sizes for the pulmonary vein (PV), pulmonary artery (PA), or bronchus (Br) are varied, thus making the determination of proper cuff size during rat lung transplantation an exercise of trial and error. By standardizing the cuffing technique to use the smallest effective cuff appropriate for the size of the vessel or bronchus, one can make the transplantation procedure safer, faster, and more successful. Since diameters of the PV, PA, and Br are related to the body weight of the rat, we present a strategy to choosing an appropriate size using a weight-based guide. Since lung volume is also related to body weight, we recommend that this relationship should also be considered when choosing the proper volume of air for donor lung inflation during warm ischemia as well as for the proper volume of PBS to be instilled during bronchoalveolar lavage (BAL) fluid collection. We also describe methods for 4th intercostal space dissection, wound closure, and sample collection from both the native and transplanted lobes.

Here, we present optimizations to a rat lung transplantation model that serve to improve outcomes. We provide a size guide for cuffs based on body weight, a measurement strategy to ascertain the 4th intercostal space, and methods of wound closure and BAL (bronchoalveolar lavage) fluid and tissue collection.

From our experience with rat lung transplantation, we have found several areas for improvement. Information in the existing literature regarding methods ...