We would like to thank Robin Nye (Tufts Medical Center), Tomoya Uchimura and Dana Cairns (Tufts University) for providing help with synovial fluid storage and centrifugation. This work was funded by the NIH (1R01AR059106-01A1) for L.Z.

A 3D system for culturing human articular chondrocytes in synovial fluid
In this work, we encapsulated human articular chondrocytes in alginate beads using a modified manufacture-suggested encapsulation protocol (Lonza, and 31). Using these 3D constructs, we have developed a system for culturing cells in a culture medium containing varied percentages of human synovial fluid and have assessed these 3D constructs for cartilage gene expression.
1. Prepare huma...

<ol>
	<li>Centers for Disease Control and P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Projected+state-specific+increases+in+self-reported+doctor-diagnosed+arthritis+and+arthritis-attributable+activity+limitations--United+States,+2005-2030.">Projected state-specific increases in self-reported doctor-diagnosed arthritis and arthritis-attributable activity limitations--United States, 2005-2030.</a> MMWR. Morb. Mortal. Wkly. Rep. 56, 423-425 (2007).</li><li>Theis, K. A., Murphy, L., Hootman, J. M., Helmick, C. G., Yelin, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prevalence+and+correlates+of+arthritis-attributable+work+limitation+in+the+US+population+among+persons+ages+18-64:+2002+National+Health+Interview+Survey+Data.">Prevalence and correlates of arthritis-attributable work limitation in the US population among persons ages 18-64: 2002 National Health Interview Survey Data.</a> Arthritis Rheum. 57, 355-363 (2007).</li><li>Chung, C., Burdick, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+cartilage+tissue.">Engineering cartilage tissue.</a> Adv. Drug. Deliv. Rev. 60, 243-262 (2008).</li><li>Glowacki, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+engineering+of+cartilage.">In vitro engineering of cartilage.</a> J. Rehabil. Res. Dev. 37, 171-177 (2000).</li><li>Chokalingam, K., Hunter, S. A., Gooch, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D-In+vitro+Effects+of+Compression+and+Time+in+Culture+on+Aggregate+Modulus+and+on+Gene+Expression+and+Protein+content+of+Collagen+Type+II+in+Murine+Chondrocytes.">3D-In vitro Effects of Compression and Time in Culture on Aggregate Modulus and on Gene Expression and Protein content of Collagen Type II in Murine Chondrocytes.</a> Tissue Eng. Part A. , (2009).</li><li>Butler, D. L., Goldstein, S. A., Guilak, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+tissue+engineering:+the+role+of+biomechanics.">Functional tissue engineering: the role of biomechanics.</a> J. Biomech. Eng. 122, 570-575 (2000).</li><li>Goldring, M. B., Goldring, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Osteoarthritis.">Osteoarthritis.</a> J. Cell. Physiol. 213, 626-634 (2007).</li><li>Zvaifler, N. J., Firestein, G. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytokines+in+chronic+inflammatory+synovitis.">Cytokines in chronic inflammatory synovitis.</a> Scand. J. Rheumatol. Suppl. 76, 203-210 (1988).</li><li>Rhee, D. K., Marcelino, J., Baker, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+secreted+glycoprotein+lubricin+protects+cartilage+surfaces+and+inhibits+synovial+cell+overgrowth.">The secreted glycoprotein lubricin protects cartilage surfaces and inhibits synovial cell overgrowth.</a> J. Clin. Invest. 115, 622-631 (2005).</li><li>Campo, G. M., Avenoso, A., Nastasi, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyaluronan+reduces+inflammation+in+experimental+arthritis+by+modulating+TLR-2+and+TLR-4+cartilage+expression.">Hyaluronan reduces inflammation in experimental arthritis by modulating TLR-2 and TLR-4 cartilage expression.</a> Biochim. Biophys. Acta. , (2011).</li><li>van de Lest, C. H., van den Hoogen, B. M., van Weeren, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Loading-induced+changes+in+synovial+fluid+affect+cartilage+metabolism.">Loading-induced changes in synovial fluid affect cartilage metabolism.</a> Biorheology. 37, 45-55 (2000).</li><li>Saxne, T., Heinegard, D., Wollheim, F. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+arthritic+synovial+fluid+influences+proteoglycan+biosynthesis+and+degradation+in+organ+culture+of+bovine+nasal+cartilage.">Human arthritic synovial fluid influences proteoglycan biosynthesis and degradation in organ culture of bovine nasal cartilage.</a> Coll. Relat. Res. 8, 233-247 (1988).</li><li>Lee, D. A., Salih, V., Stockton, E. F., Stanton, J. S., Bentley, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+normal+synovial+fluid+on+the+metabolism+of+articular+chondrocytes+in+vitro.">Effect of normal synovial fluid on the metabolism of articular chondrocytes in vitro.</a> Clin. Orthop. Relat. Res. , 228-238 (1997).</li><li>Schalkwijk, J., Joosten, L. A., van den Berg, W. B., van de Putte, L. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chondrocyte+nonresponsiveness+to+insulin-like+growth+factor+1+in+experimental+arthritis.">Chondrocyte nonresponsiveness to insulin-like growth factor 1 in experimental arthritis.</a> Arthritis Rheum. 32, 894-900 (1989).</li><li>Schalkwijk, J., Joosten, L. A., van den Berg, W. B., van Wyk, J. J., van de Putte, L. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insulin-like+growth+factor+stimulation+of+chondrocyte+proteoglycan+synthesis+by+human+synovial+fluid.">Insulin-like growth factor stimulation of chondrocyte proteoglycan synthesis by human synovial fluid.</a> Arthritis Rheum. 32, 66-71 (1989).</li><li>Joosten, L. A., Schalkwijk, J., van den Berg, W. B., van de Putte, L. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chondrocyte+unresponsiveness+to+insulin-like+growth+factor-1.+A+novel+pathogenetic+mechanisms+for+cartilage+destruction+in+experimental+arthritis.">Chondrocyte unresponsiveness to insulin-like growth factor-1. A novel pathogenetic mechanisms for cartilage destruction in experimental arthritis.</a> Agents Actions. 26, 193-195 (1989).</li><li>Schuerwegh, A. J., Dombrecht, E. J., Stevens, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synovial+fluid+and+peripheral+blood+immune+complexes+of+patients+with+rheumatoid+arthritis+induce+apoptosis+in+cytokine-activated+chondrocytes.">Synovial fluid and peripheral blood immune complexes of patients with rheumatoid arthritis induce apoptosis in cytokine-activated chondrocytes.</a> Rheumatol. Int. 27, 901-909 (2007).</li><li>Hegewald, A. A., Ringe, J., Bartel, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyaluronic+acid+and+autologous+synovial+fluid+induce+chondrogenic+differentiation+of+equine+mesenchymal+stem+cells:+a+preliminary+study.">Hyaluronic acid and autologous synovial fluid induce chondrogenic differentiation of equine mesenchymal stem cells: a preliminary study.</a> Tissue Cell. 36, 431-438 (2004).</li><li>Xu, Q. R., Dong, Y. H., Chen, S. L., Bao, C. D., Du, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Degeneration+of+normal+articular+cartilage+induced+by+late+phase+osteoarthritic+synovial+fluid+in+beagle+dogs.">Degeneration of normal articular cartilage induced by late phase osteoarthritic synovial fluid in beagle dogs.</a> Tissue Cell. 41, 13-22 (2009).</li><li>Kruger, J. P., Endres, M., Neumann, K., Haupl, T., Erggelet, C., Kaps, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chondrogenic+differentiation+of+human+subchondral+progenitor+cells+is+impaired+by+rheumatoid+arthritis+synovial+fluid.">Chondrogenic differentiation of human subchondral progenitor cells is impaired by rheumatoid arthritis synovial fluid.</a> J. Orthop. Res. 28, 819-827 (2010).</li><li>Steinhagen, J., Bruns, J., Niggemeyer, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perfusion+culture+system:+Synovial+fibroblasts+modulate+articular+chondrocyte+matrix+synthesis+in+vitro.">Perfusion culture system: Synovial fibroblasts modulate articular chondrocyte matrix synthesis in vitro.</a> Tissue Cell. 42, 151-157 (2010).</li><li>Yang, K. G., Saris, D. B., Verbout, A. J., Creemers, L. B., Dhert, W. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+synovial+fluid+from+injured+knee+joints+on+in+vitro+chondrogenesis.">The effect of synovial fluid from injured knee joints on in vitro chondrogenesis.</a> Tissue Eng. 12, 2957-2964 (2006).</li><li>Skoog, V., Widenfalk, B., Ohlsen, L., Wasteson, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+growth+factors+and+synovial+fluid+on+chondrogenesis+in+perichondrium.">The effect of growth factors and synovial fluid on chondrogenesis in perichondrium.</a> Scand. J. Plast. Reconstr. Surg. Hand. Surg.. 24, 89-95 (1990).</li><li>Nuver-Zwart, I., Schalkwijk, J., Joosten, L. A., van den Berg, W. B., van de Putte, L. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+synovial+fluid+and+synovial+fluid+cells+on+chondrocyte+metabolism+in+short+term+tissue+culture.">Effects of synovial fluid and synovial fluid cells on chondrocyte metabolism in short term tissue culture.</a> J. Rheumatol. 15, 210-216 (1988).</li><li>Beekhuizen, M., Bastiaansen-Jenniskens, Y. M., Koevoet, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Osteoarthritic+synovial+tissue+inhibits+proteoglycan+production+in+human+osteoarthritic+cartilage;+Establishment+and+characterisation+of+a+long-term+coculture.">Osteoarthritic synovial tissue inhibits proteoglycan production in human osteoarthritic cartilage; Establishment and characterisation of a long-term coculture.</a> Arthritis Rheum. , (2011).</li><li>Rodrigo, J. J., Steadman, J. R., Syftestad, G., Benton, H., Silliman, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+human+knee+synovial+fluid+on+chondrogenesis+in+vitro.">Effects of human knee synovial fluid on chondrogenesis in vitro.</a> Am. J. Knee. Surg. 8, 124-129 (1995).</li><li>van den Hoogen, B. M., van de Lest, C. H., van Weeren, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Loading-induced+changes+in+synovial+fluid+affect+cartilage+metabolism.">Loading-induced changes in synovial fluid affect cartilage metabolism.</a> Br. J. Rheumatol. 37, 671-676 (1998).</li><li>Webb, G. R., Westacott, C. I., Elson, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Osteoarthritic+synovial+fluid+and+synovium+supernatants+up-regulate+tumor+necrosis+factor+receptors+on+human+articular+chondrocytes.">Osteoarthritic synovial fluid and synovium supernatants up-regulate tumor necrosis factor receptors on human articular chondrocytes.</a> Osteoarthritis Cartilage. 6, 167-176 (1998).</li><li>Kook, S. H., Son, Y. O., Lee, K. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hypoxia+affects+positively+the+proliferation+of+bovine+satellite+cells+and+their+myogenic+differentiation+through+up-regulation+of+MyoD.">Hypoxia affects positively the proliferation of bovine satellite cells and their myogenic differentiation through up-regulation of MyoD.</a> Cell. Biol. Int. 32, 871-878 (2008).</li><li>Knobloch, T. J., Madhavan, S., Nam, J., Agarwal, S., Agarwal, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+chondrocytic+gene+expression+by+biomechanical+signals.">Regulation of chondrocytic gene expression by biomechanical signals.</a> Crit. Rev. Eukaryot. Gene. Expr. 18, 139-150 (2008).</li><li>Guo, J. F., Jourdian, G. W., MacCallum, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Culture+and+growth+characteristics+of+chondrocytes+encapsulated+in+alginate+beads.">Culture and growth characteristics of chondrocytes encapsulated in alginate beads.</a> Connect. Tissue. Res. 19, 277-297 (1989).</li><li>Toegel, S., Huang, W., Piana, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selection+of+reliable+reference+genes+for+qPCR+studies+on+chondroprotective+action.">Selection of reliable reference genes for qPCR studies on chondroprotective action.</a> BMC. Mol. Biol. 8, 13-13 (2007).</li><li>Lin, Z., Fitzgerald, J. B., Xu, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+expression+profiles+of+human+chondrocytes+during+passaged+monolayer+cultivation.">Gene expression profiles of human chondrocytes during passaged monolayer cultivation.</a> J. Orthop. Res. 26, 1230-1237 (2008).</li><li>Goessler, U. R., Bieback, K., Bugert, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+chondrocytes+differentially+express+matrix+modulators+during+in+vitro+expansion+for+tissue+engineering.">Human chondrocytes differentially express matrix modulators during in vitro expansion for tissue engineering.</a> Int. J. Mol. Med. 16, 509-515 (2005).</li><li>Anat, 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> 121, 107-118 (1976).</li></ol>

We have nothing to disclose.

In this report, we developed a method that allows for the culture of human articular chondrocytes in a 3D environment in medium that contains high concentrations of human synovial fluid. Synovial fluid is one of the major components that constitute the natural environment in the joint cavity, where articular chondrocytes reside. However, the viscosity of the synovial fluid has been a major challenge for three-dimensional long-term culturing of chondrocytes. To overcome the challenge of maintaining even nutrient distribut...

Table of specific reagents and equipment: 
 <table border="1">
 <tr>
 <th>Name of the Reagent</th>
 <th>Company</th>
 <th>Catalogue Number</th>
 <th>Comments</th>
 </tr>
 <tr>
 <td>Alginate (Alginic Acid sodium salt)</td>
 <td>Sigma</td>
 <td>A2158-250G</td>
 <td>2.4% solution stored at 40&deg;C</td>
 </tr>
 <tr>
 <td>Calcium Chloride Dihydrate, Granular</td>
 <td>J.T. Baker</td>
 <td>A19339</td>
 <td></td>
 </tr>
 <tr>
 <td width="239" rowspan="2" >Chondrogenic Growth media</td>
 <td width="254" rowspan="2" >Lonza</td>
 <td width="182" >CC-3156 (base media)</td>
 <td width="141" rowspan="2" >&nbsp;</td>
 </tr>
 <tr>
 <td width="182" >CC-4409 (supplement)</td>
 </tr>
 <tr>
 <td width="239" rowspan="2" >Chondrogenic Differentiation Media</td>
 <td width="254" rowspan="2" >Lonza</td>
 <td width="182" >CC-3226 (base media)</td>
 <td width="141" rowspan="2" >&nbsp;</td>
 </tr>
 <tr>
 <td width="182" >CC-4408 (supplement)</td>
 </tr>
 <tr>
 <td>Human articular chondrocytes</td>
 <td>Lonza</td>
 <td >CC-2550</td>
 <td></td>
 </tr>
 <tr>
 <td>Dapi (4&prime;,6-Diamidino-2-phenylindole dihydrochloride)</td>
 <td>Sigma-Aldrich</td>
 <td >D9542</td>
 <td></td>
 </tr>
 <tr>
 <td>RNeasy mini kit (for RNA extraction)</td>
 <td>Qiagen</td>
 <td >74104</td>
 <td></td>
 </tr>
 <tr>
 <td>PCR reagents: SYBR-green</td>
 <td>Quanta</td>
 <td >95053-500</td>
 <td></td>
 </tr>
 <tr>
 <td>12 ml syringe</td>
 <td>Tyco-Kendall-Monoject</td>
 <td >512852</td>
 <td></td>
 </tr>
 <tr>
 <td>22-Gague Hypodermic Needle </td>
 <td>Tyco-Kendall-Monoject</td>
 <td >8881</td>
 <td></td>
 </tr>
 <tr>
 <td>Microscope</td>
 <td>Olympus</td>
 <td >IX71</td>
 <td></td>
 </tr>
 <tr>
 <td>Platform rocker </td>
 <td>Thermoscientific thermolyne</td>
 <td >Vari-mix</td>
 <td></td>
 </tr>
 <tr>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td >&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Primers sequences</td>
 <td></td>
 <td ></td>
 <td></td>
 </tr>
 <tr>
 <td>Collagen IIa-forward</td>
 <td>5'-TTC ATC CCA CCC TCT CAC AGT-3'</td>
 <td ></td>
 <td></td>
 </tr>
 <tr>
 <td>Collagen IIa-reverse</td>
 <td>5'-CCTCTGCCTTGACCCGAA-3'</td>
 <td ></td>
 <td></td>
 </tr>
 <tr>
 <td>MMP13-forward</td>
 <td>5'-TGT GCC CTT CTT CAC ACA GAC ACT-3'</td>
 <td ></td>
 <td></td>
 </tr>
 <tr>
 <td>MMP13-reverse</td>
 <td>5'-GAG AGC AGA CTT TGA GTC ATT GCC-3'</td>
 <td ></td>
 <td></td>
 </tr>
 <tr>
 <td>Caspase 3-forward</td>
 <td>5'-TCA TTA TTC AGG CCT GCC GTG GTA-3'</td>
 <td ></td>
 <td></td>
 </tr>
 <tr>
 <td>Caspase 3-reverse</td>
 <td>5'-TGG ATG AAC CAG GAG CCA TCC TTT -3'</td>
 <td ></td>
 <td></td>
 </tr>
 </table>

a 3d system for culturing human articular chondrocytes in synovial fluid

Cartilage destruction is a central pathological feature of osteoarthritis, a leading cause of disability in the US. Cartilage in the adult does not regenerate very efficiently in vivo; and as a result, osteoarthritis leads to irreversible cartilage loss and is accompanied by chronic pain and immobility 1,2. Cartilage tissue engineering offers promising potential to regenerate and restore tissue function. This technology typically involves seeding chondrocytes into natural or synthetic scaffolds and culturing the resulting 3D construct in a balanced medium over a period of time with a goal of engineering a biochemically and biomechanically mature tissue that can be transplanted into a defect site in vivo 3-6. Achieving an optimal condition for chondrocyte growth and matrix deposition is essential for the success of cartilage tissue engineering. 
 In the native joint cavity, cartilage at the articular surface of the bone is bathed in synovial fluid. This clear and viscous fluid provides nutrients to the avascular articular cartilage and contains growth factors, cytokines and enzymes that are important for chondrocyte metabolism 7,8. Furthermore, synovial fluid facilitates low-friction movement between cartilaginous surfaces mainly through secreting two key components, hyaluronan and lubricin 9 10. In contrast, tissue engineered cartilage is most often cultured in artificial media. While these media are likely able to provide more defined conditions for studying chondrocyte metabolism, synovial fluid most accurately reflects the natural environment of which articular chondrocytes reside in.
 Indeed, synovial fluid has the advantage of being easy to obtain and store, and can often be regularly replenished by the body. Several groups have supplemented the culture medium with synovial fluid in growing human, bovine, rabbit and dog chondrocytes, but mostly used only low levels of synovial fluid (below 20&#37;) 11-25. While chicken, horse and human chondrocytes have been cultured in the medium with higher percentage of synovial fluid, these culture systems were two-dimensional 26-28. Here we present our method of culturing human articular chondrocytes in a 3D system with a high percentage of synovial fluid (up to 100&#37;) over a period of 21 days. In doing so, we overcame a major hurdle presented by the high viscosity of the synovial fluid. This system provides the possibility of studying human chondrocytes in synovial fluid in a 3D setting, which can be further combined with two other important factors (oxygen tension and mechanical loading) 29,30 that constitute the natural environment for cartilage to mimic the natural milieu for cartilage growth. Furthermore, This system may also be used for assaying synovial fluid activity on chondrocytes and provide a platform for developing cartilage regeneration technologies and therapeutic options for arthritis.

Watch this Scientific Journal Video about A 3D System for Culturing Human Articular Chondrocytes in Synovial Fluid at JoVE.com

A 3D System for Culturing Human Articular Chondrocytes in Synovial Fluid

A 3D system of culturing human articular chondrocytes in high levels of synovial fluid is described. Synovial fluid reflects the most natural microenvironment for articular cartilage, and can be easily obtained and stored. This system thus can be used for studying cartilage regeneration and for screening therapeutics for treating arthritis.

Cartilage destruction is a central pathological feature of osteoarthritis, a leading cause of disability in the US. Cartilage in the adult does not ...

a-3d-system-for-culturing-human-articular-chondrocytes-synovial

Research

JoVE Journal

Biology

20.7K Görüntüleme.  Tufts University School of Medicine. Sinovyal sıvıda yüksek düzeyde insan eklem kondrosit kültür 3D sistemi açıklanmıştır. Sinovyal sıvı eklem kıkırdağı için en doğal mikroçevresinin yansıtır ve kolayca elde ve saklanabilir. Bu sistem, böylece kıkırdak rejenerasyon eğitim ve artrit tedavisi için tarama terapötikler için kullanılabilir.