This work was supported by the Research Program funded by the Korea Centers for Disease Control and Prevention (HI13D2188).

Ethics Statement: This study protocol was approved by the institutional review board of The Catholic University of Korea (KC12TISI0861).
1. Synoviocyte Isolation and Expansion
<ol>
	<li>Synoviocyte Isolation
	<ol>
		<li>Sterilize two pairs of surgical scissors and one pair of forceps.</li>
		<li>Transfer the synovial tissue to a 100 mm dish and wash with 5 ml of phosphate-buffered saline (PBS) containing 1% penicillin/streptomycin.</li>
		<li>Cut off the yellowish fat tissue and bone residues. Transfer the trimmed tissue to a well of a 6-well plate and add 5 ml of Dulbecco&#39;s modified Eagle&#39;s medium (DMEM) with 20% Fetal bovine serum (FBS).</li>
		<li>Chop the tissues with the scissors until the pieces are small enough to penetrate a disposable pipette.</li>
		<li>Transfer the tissue-containing media to a 50 ml conical tube. Harvest the remaining material by adding 5 ml of DMEM with 20% FBS to the 6-well plate and then transfer to the tube.</li>
		<li>Thaw collagenase on ice. Add collagenase to a final concentration of 0.01% and seal the tube with parafilm. Incubate in a water bath at 37 &#176;C with shaking for 4 hr.</li>
		<li>After incubation, fill the tube with DMEM with 20% FBS, until the total volume is 50 ml and centrifuge at 300 x g, RT for 10 min.</li>
		<li>Remove the supernatant without disturbing the pellet and add 40 ml of media to resuspend the pellet.</li>
		<li>Repeat steps 1.1.10-1.1.11.</li>
		<li>Resuspend the pellet in 25 ml of DMEM with 20% FBS and wait for the large clumps of tissue to sink to the bottom.</li>
		<li>Transfer the supernatant to a 100 mm dish and incubate at 37 &#176;C in 5% CO2 for 14 day.</li>
	</ol>
	</li>
	<li>Synoviocyte Maintenance and Expansion
	<ol>
		<li>Discard the used media from the plate and wash the cells with 5 ml of PBS.</li>
		<li>Add 1 ml PBS/1 mM EDTA and incubate at 37 &#176;C in 5% CO2 for 2 min.</li>
		<li>Tap the dish gently and transfer the cells to a 15 ml conical tube. Centrifuge the cells at 250 x g, RT for 2 min.</li>
		<li>Remove the supernatant without disturbing the pellet and resuspend the pellet in 30 ml of DMEM with 20% FBS.</li>
		<li>Transfer the cells to 3 x 100 mm dishes, without leaving any visible leftover material.</li>
		<li>Replace the media with fresh media every 3 d. Split the cells at 80% confluency using 1 ml PBS/1 mM EDTA. Maintain until passage 3 before use. Divide each dish of cells into 3 dishes in every split. 
		NOTE: After reaching passage 3, cells that are not going to be used immediately can be frozen.</li>
	</ol>
	</li>
</ol>
2. Reprogramming FLSs Using Lentiviruses-encoding Yamanaka Factors
<ol>
	<li>Transduction (D0)
	<ol>
		<li>Seed 3 &#215; 104 cells per well of a 6-well plate in growth media (500 ml of DMEM supplemented with 10% FBS and 1% penicillin/streptomycin). Incubate the cells O/N at 37 &#176;C in 5% CO2.</li>
		<li>The following day, remove one vial of lentivirus containing 4 Yamanaka factors: Oct4, Klf4, Sox2 and c-Myc from the freezer and thaw at 4 &#176;C. Note: Lentivirus was produced by the procedure described in our previous study11.</li>
		<li>While thawing the virus, change the media to FLS growth media (20% FBS plus antibiotics in DMEM) containing 10 &#181;g/ml hexadimethrine bromide and 50 &#181;g/ml ascorbic acid.</li>
		<li>After changing the media, add 30 &#181;l of lentivirus to the cells and mix gently. To improve infection, centrifuge the plate at 680 x g, 35 &#176;C for 30 min.</li>
		<li>After centrifugation, incubate the cells at 37 &#176;C in 5% CO2.</li>
	</ol>
	</li>
	<li>Maintenance Until Reprogramming is Visible
	<ol>
		<li>For 3 day, replace the media daily with FLS growth media containing 0.1 mM sodium butyrate and 50 &#181;g/ml ascorbic acid.</li>
		<li>The next day, replace the media with a mixture of FLS growth media and iPSC media (1:1 ratio) containing 0.1 mM sodium butyrate and 50 &#181;g/ml ascorbic acid. 
		Note: The components of the iPSC media is given in the materials/equipment list.</li>
	</ol>
	</li>
	<li>Splitting Cells for Colony Formation
	<ol>
		<li>Prepare a vitronectin-coated 6-well plate.
		<ol>
			<li>Add 60 &#181;l vitronectin to 6 ml PBS without Ca2+ and Mg2+. Put 2 ml of mixture into each wells and incubate in RT for at least 1 hr. Note: The working concentration of vitronectin is 5 &#181;g/mL.</li>
		</ol>
		</li>
		<li>On D5, wash the cells with PBS.</li>
		<li>Add 1 ml PBS/1 mM EDTA to detach the cells and incubate at 37 &#176;C, 5% CO2 for 2 min.</li>
		<li>Harvest the cells and centrifuge at 250 x g, RT for 2 min.</li>
		<li>Split the cells at 3 different ratios (1:3, 1:6, and 1:9) to achieve different confluencies. Add 900 &#181;l of media to the cell pellet and resuspend. Add 300, 150, and 100 &#181;l of the cell mixture per well of a 6-well plate to achieve a ratio of 1:3, 1:6, and 1:9, respectively.</li>
		<li>Replace the media daily with iPSC media until colonies appear. Colonies will appear after about D18. Note: At this stage, iPSC colonies co-exist with the non-reprogrammed FLSs.</li>
	</ol>
	</li>
	<li>Colony picking
	<ol>
		<li>Prepare a 48-well vitronectin-coated plate by adding 500 &#181;l vitronectin to the wells, and incubate at RT for at least 1 hr.</li>
		<li>Place the microscope on a clean bench, and remove the 6-well plate from the incubator.</li>
		<li>Remove the vitronectin solution from the 48-well plate and add 500 &#181;l iPSC media supplemented with 10mM Rho-associated, coiled-coil containing protein kinase (ROCK) inhibitor.</li>
		<li>Using a 10p pipette tip, cut around the colony. Transfer the picked colony to one well of the 48-well plate.</li>
		<li>After picking several colonies, incubate the cells at 37 &#176;C, 5% CO2.</li>
		<li>Maintain the cells until the colonies are big enough for transfer. Note: We usually spilt the cells when the colony gets out of the visible field of the microscope, when viewed at 100X magnification.</li>
	</ol>
	</li>
</ol>
3. Immunofluorescence Staining
<ol>
	<li>Cell Preparation
	<ol>
		<li>Place a sterile 18 mm cover glass into a 12-well plate.</li>
		<li>Add 1 ml of PBS to cool and rinse the cover glass.</li>
		<li>Replace with 1 ml of a 10 &#181;g/ml vitronectin solution.</li>
		<li>Incubate the plate at RT for at least 1 hr.</li>
		<li>Discard the vitronectin solution and plate iPSCs in the vitronectin-coated 12-well plate and culture for 7 days at 37 &#176;C, 5% CO2, changing the media daily.</li>
	</ol>
	</li>
	<li>Cell Staining
	<ol>
		<li>Discard the culture media and wash the cells with PBS once.</li>
		<li>Fix the cells in 0.4% paraformaldehyde (PFA) for 30 min at RT.</li>
		<li>Permeabilize the cells with 0.1% Triton X-100 for 5 min at RT.</li>
		<li>Remove the permeabilization solution and block with PBS containing 2% bovine serum albumin (BSA) for 30 min at RT.</li>
		<li>Dilute the antibodies in PBS containing 2% BSA according to Table 1. Incubate the cells with the primary antibodies for 2 hr at RT.</li>
		<li>Add the secondary antibody (diluted 1:200) and incubate the cells for 1 hr at RT, avoiding light.</li>
		<li>Treat the cells with 1 &#181;l/mL DAPI for 10 min.</li>
		<li>Place the cover glass on top of the slide glass with antifade reagent and incubate at RT for 24 hr, avoiding light.</li>
		<li>Verify expression with a fluorescence microscope.</li>
	</ol>
	</li>
</ol>
4. Real-time Polymerase Chain Reaction (RT-PCR)
<ol>
	<li>Extract mRNA from the cell pellet using the guanidinium thiocyanate-phenol-chloroform extraction method11.</li>
	<li>Amplify cDNA from 2 &#181;g of total mRNA using reverse transcription11.</li>
	<li>Mix the components required for PCR using 2 &#181;l of cDNA template11.</li>
	<li>Perform RT-PCR and verify the results by gel electrophoresis11.</li>
</ol>
5. Alkaline Phosphatase (AP) Staining
<ol>
	<li>Culture iPSCs for 5-7 days at 37 &#176;C, 5% CO2 prior to staining.</li>
	<li>Aspirate the media and fix the cells with 4% PFA for 1 min.</li>
	<li>Discard the fixative and rinse the cells with 1X rinse buffer.</li>
	<li>Prepare the reagents for AP staining. Mix the reagents in the following ratio: Fast Red Violet : Naphthol AS-BI phosphate solution : water = 2:1:1.</li>
	<li>Incubate the cells with the staining solution at RT for 15 min, avoiding light.</li>
	<li>Discard the staining solution and rinse the cells with rinse buffer.</li>
	<li>Cover the cells with PBS to prevent drying and verify expression using a bright-field microscope.</li>
</ol>

<ol>
	<li>Yu, 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=Induced+pluripotent+stem+cell+lines+derived+from+human+somatic+cells.">Induced pluripotent stem cell lines derived from human somatic cells.</a> Science. 318 (5858), 1917-1920 (2007).</li><li>Takahashi, K., 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=Induction+of+pluripotent+stem+cells+from+adult+human+fibroblasts+by+defined+factors.">Induction of pluripotent stem cells from adult human fibroblasts by defined factors.</a> Cell. 131 (5), 861-872 (2007).</li><li>Takahashi, K., Yamanaka, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+pluripotent+stem+cells+from+mouse+embryonic+and+adult+fibroblast+cultures+by+defined+factors.">Induction of pluripotent stem cells from mouse embryonic and adult fibroblast cultures by defined factors.</a> Cell. 126 (4), 663-676 (2006).</li><li>Zhou, 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=Generation+of+human+induced+pluripotent+stem+cells+from+urine+samples.">Generation of human induced pluripotent stem cells from urine samples.</a> Nat Protoc. 7 (12), 2080-2089 (2012).</li><li>Haase, A., 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=Generation+of+induced+pluripotent+stem+cells+from+human+cord+blood.">Generation of induced pluripotent stem cells from human cord blood.</a> Cell Stem Cell. 5 (4), 434-441 (2009).</li><li>Loh, Y. H., 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=Generation+of+induced+pluripotent+stem+cells+from+human+blood.">Generation of induced pluripotent stem cells from human blood.</a> Blood. 113 (22), 5476-5479 (2009).</li><li>Aasen, 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=Efficient+and+rapid+generation+of+induced+pluripotent+stem+cells+from+human+keratinocytes.">Efficient and rapid generation of induced pluripotent stem cells from human keratinocytes.</a> Nat Biotechnol. 26 (11), 1276-1284 (2008).</li><li>Scott, D. L., Wolfe, F., Huizinga, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rheumatoid+arthritis.">Rheumatoid arthritis.</a> Lancet. 376 (9746), 1094-1108 (2010).</li><li>Chang, S. K., Gu, Z., Brenner, M. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fibroblast-like+synoviocytes+in+inflammatory+arthritis+pathology:+the+emerging+role+of+cadherin-11.">Fibroblast-like synoviocytes in inflammatory arthritis pathology: the emerging role of cadherin-11.</a> Immunol Rev. 233 (1), 256-266 (2010).</li><li>Bartok, B., 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=Fibroblast-like+synoviocytes:+key+effector+cells+in+rheumatoid+arthritis.">Fibroblast-like synoviocytes: key effector cells in rheumatoid arthritis.</a> Immunol Rev. 233 (1), 233-255 (2010).</li><li>Lee, 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=Generation+of+disease-specific+induced+pluripotent+stem+cells+from+patients+with+rheumatoid+arthritis+and+osteoarthritis.">Generation of disease-specific induced pluripotent stem cells from patients with rheumatoid arthritis and osteoarthritis.</a> Arthritis Res Ther. 16 (1), R41 (2014).</li></ol>

The authors have nothing to disclose.

Before the discovery of iPSCs, scientists mainly used ESCs to study stem cell biology and other cell lineages through differentiation. However, ESCs originate from the inner mass of a blastocyst, which is an early-stage embryo. To isolate ESCs, destruction of the blastocyst is inevitable, raising ethical issues that are impossible to overcome. Moreover, although ESCs have stemness characteristics and pluripotency, they cannot be obtained from individuals and are sometimes not an ideal tool for personalized analysis and d...

Pluripotent stem cells are the next-generation platform in various clinical and biological fields. They are a promising tool that can be used in disease modeling, drug screening, and regenerative medical therapy. Human Embryonic Stem Cells (hESCs) were mainly used to study and understand pluripotent cells. However, isolated by the destruction of the human blastocyst, hESCs are associated with several ethical concerns. In 2007, Dr. Shinya Yamanaka and his team reversed the cell programming process and developed stem cells from human adult somatic cells1,2. Therefore, unlike hESCs, induced-Pluripotent Stem Cells (iPSCs) can be generated from mature somatic cells, avoiding the ethical hurdles.
Usually, iPSCs are generated by the delivery of four exogenous genes: Oct4, Sox2, Klf4, and c-Myc. These Yamanaka factors are originally delivered using lentiviral and retroviral systems. The first iPSCs were derived from mouse somatic cells3. Afterwards, the technique was applied to human dermal fibroblasts1,2. Subsequent studies successfully generated iPSCs from various sources, such as urine4, blood5,6, keratinocytes7, and several other cell types. However, there are some somatic cells that have not been used in reprogramming, and screening of the reprogramming capabilities of various cell types from specific tissues in disease state, is still required.
Rheumatoid arthritis (RA) is a disease that can strike all joints and lead to autoimmune conditions in other organs. RA affects about 1% of adults in the developed world. It is a rather common disease and its incidence increases each year8. However, RA is hard to identify in the early stages and oncebone destruction occurs there is no treatment that can recover the damage. Moreover, drug efficacy differs from patient to patient, and it is hard to predict the medicine that is required. Therefore, the development of a drug-screening method is needed, and a cell material that can reflect the conditions of RA is required.
Fibroblast-like Synoviocytes (FLSs) are an active cellular participant in the pathogenesis of RA9,10. FLSs exist in the synovial intimal lining between the joint capsule and cavity, which is also referred to as the synovium. By supporting the joint structure and providing nutrients to the surrounding cartilage, FLSs usually play a crucial role in joint function and maintenance. However, FLSs in RA have an invasive phenotype. RA FLSs have a cancer-like phenotype, eventually destroying the surrounding bone by infinite proliferation10. With this unique characteristic, FLSs can be used as a promising material that can reflect the pathobiology of RA. Yet, these cells are rarely produced, and the cell phenotypes alter as the cells go through several passages in in vitro conditions. Therefore, it can be complicated to use RA FLSs as a tool that can represent the patient&#39;s condition.
Theoretically, RA patient-derived iPSCs (RA-iPSCs) can become an ideal tool for drug screening and further research. Generated iPSCs have self-renewal ability and can be maintained and expanded in vitro. With pluripotency, these cells can be differentiated into mature chondrocyte and osteocyte lineages, which can contribute cell material for specific research in RA and other bone-related diseases11.
In this study, we demonstrate how to isolate and expand FLSs from a surgically removed synovium, and how to generate RA-iPSCs from FLSs using lentiviruses containing Yamanaka factors.

<table><tbody><tr><td>100 mm Dish</td><td>TPP</td><td>93100</td><td></td></tr><tr><td>6-well Plate</td><td>TPP</td><td>92006</td><td></td></tr><tr><td>50 ml Cornical Tube</td><td>SPL</td><td>50050</td><td></td></tr><tr><td>15 mlL Cornical Tube</td><td>SPL</td><td>50015</td><td></td></tr><tr><td>10 ml Disposable Pipette</td><td>Falcon</td><td>7551</td><td></td></tr><tr><td>5 ml Disposable Pipette</td><td>Falcon</td><td>7543</td><td></td></tr><tr><td>12-well Plate</td><td>TPP</td><td>92012</td><td></td></tr><tr><td>&lt;strong&gt;FLS Isolation Materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Surgical Scissors</td><td></td><td></td><td></td></tr><tr><td>Surgical Forcep</td><td></td><td></td><td></td></tr><tr><td>DPBS</td><td>Life Technologies</td><td>14190-144</td><td></td></tr><tr><td>DMEM</td><td>Life Technologies</td><td>11995-073</td><td></td></tr><tr><td>Penicilin Streptomycin</td><td>Sigma Aldrich</td><td>P4333</td><td></td></tr><tr><td>Fetal Bovine Serum (FBS)</td><td>Life Technologies</td><td>16000-044</td><td></td></tr><tr><td>Collagenase</td><td>Sigma Aldrich</td><td>C6885-100MG</td><td></td></tr><tr><td>Parafilm</td><td>Sigma Aldrich</td><td>54956</td><td></td></tr><tr><td>PBS/1 mM EDTA</td><td>Life Technologies</td><td>12604-039</td><td></td></tr><tr><td>&lt;strong&gt;iPSC Generation Materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>DMEM</td><td>Life Technologies</td><td>11885</td><td></td></tr><tr><td>MEM Non-Essential Amino Acids Solution (100x)</td><td>Life Technologies</td><td>11140-050</td><td></td></tr><tr><td>&amp;beta;-Mercaptoethanol</td><td>Sigma Aldrich</td><td>M3148</td><td></td></tr><tr><td>Polybrene</td><td>Chemicon</td><td>TR-1003-G</td><td></td></tr><tr><td>Penicilin Streptomycin</td><td>Life Technologies</td><td>P4333</td><td></td></tr><tr><td>Fetal Bovine Serum (FBS)</td><td>Life Technologies</td><td>16000-044</td><td></td></tr><tr><td>DPBS</td><td>Life Technologies</td><td>14190-144</td><td></td></tr><tr><td>Lentivirus</td><td></td><td></td><td></td></tr><tr><td>DMEM/F12, HEPES</td><td>Life Technologies</td><td>11330-057</td><td>iPSC media ingredient (500 ml)</td></tr><tr><td>Sodium Bicarbonate</td><td>Life Technologies</td><td>25080-094</td><td>iPSC media ingredient (Conc.: 543 &amp;mu;g/ml)</td></tr><tr><td>Sodium Selenite</td><td>Sigma Aldrich</td><td>S5261</td><td>iPSC media ingredient&amp;nbsp; (Conc.: 14 ng/mL)</td></tr><tr><td>Human Transfferin</td><td>Sigma Aldrich</td><td>T3705</td><td>iPSC media ingredient (Conc.: 10.7 &amp;mu;g/ml)</td></tr><tr><td>Basic FGF2</td><td>Peprotech</td><td>100-18B</td><td>iPSC media ingredient&amp;nbsp; (Conc.: 100 ng/ml)</td></tr><tr><td>Human Insulin</td><td>Life Technologies</td><td>12585-014</td><td>iPSC media ingredient (Conc.: 20 &amp;mu;g/ml)</td></tr><tr><td>Human TGF&amp;beta;1</td><td>Peprotech</td><td>100-21</td><td>iPSC media ingredient (Conc.: 2 ng/ml)</td></tr><tr><td>Ascorbic Acid</td><td>Sigma Aldrich</td><td>A8960</td><td>iPSC media ingredient&amp;nbsp; (Conc.: 64 &amp;mu;g/ml)</td></tr><tr><td>Polybrene</td><td>Chemicon</td><td>TR-1003</td><td></td></tr><tr><td>Sodium Butyrate</td><td>Sigma Aldrich</td><td>B5887</td><td></td></tr><tr><td>Vitronectin</td><td>Life Technologies</td><td>A14700</td><td></td></tr><tr><td>ROCK Inhibitor</td><td>Sigma Aldrich</td><td>Y0503</td><td></td></tr><tr><td>&lt;strong&gt;Guality Control Materials&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>18 mm Cover Glass</td><td>Superior</td><td>HSU-0111580</td><td></td></tr><tr><td>4% Paraformaldyhyde (PFA)</td><td>Tech &amp;amp; Innovation</td><td>BPP-9004</td><td></td></tr><tr><td>Triton X-100</td><td>BIOSESANG</td><td>9002-93-1</td><td></td></tr><tr><td>Bovine Serum Albumin (BSA)</td><td>Vector Lab</td><td>SP-5050</td><td></td></tr><tr><td>Anti-SSEA4 Antibody</td><td>Millipore</td><td>MAB4304</td><td></td></tr><tr><td>Anti-Oct4 Antibody</td><td>Santa Cruz</td><td>SC9081</td><td></td></tr><tr><td>Anti-TRA-1-60 Antibody</td><td>Millipore</td><td>MAB4360</td><td></td></tr><tr><td>Anti-Sox2 Antibody</td><td>Biolegend</td><td>630801</td><td></td></tr><tr><td>Anti-TRA-1-81 Antibody</td><td>Millipore</td><td>MAB4381</td><td></td></tr><tr><td>Anti-Klf4 Antibody</td><td>Abcam</td><td>ab151733</td><td></td></tr><tr><td>Alexa Fluor 488 goat anti-mouse IgG (H+L) antibody</td><td>Molecular Probe</td><td>A11029</td><td></td></tr><tr><td>Alexa Fluor 594 goat anti-rabbit IgG (H+L) antibody</td><td>Molecular Probe</td><td>A11037</td><td></td></tr><tr><td>DAPI</td><td>Molecular Probe</td><td>D1306</td><td></td></tr><tr><td>Prolong gold antifade reagent</td><td>Invitrogen</td><td>P36934</td><td></td></tr><tr><td>Slide Glass, Coated</td><td>Hyun Il Lab-Mate</td><td>HMA-S9914</td><td></td></tr><tr><td>Trizol</td><td>Invitrogen</td><td>15596-018</td><td></td></tr><tr><td>Chloroform</td><td>Sigma Aldrich</td><td>366919</td><td></td></tr><tr><td>Isoprypylalcohol</td><td>Millipore</td><td>109634</td><td></td></tr><tr><td>Ethanol</td><td>Duksan</td><td>64-17-5</td><td></td></tr><tr><td>RevertAid First Strand cDNA Synthesis kit</td><td>Thermo Scientfic</td><td>K1622</td><td></td></tr><tr><td>i-Taq DNA Polymerase</td><td>iNtRON BIOTECH</td><td>25021</td><td></td></tr><tr><td>UltraPure 10x TBE Buffer</td><td>Life Technologies</td><td>15581-044</td><td></td></tr><tr><td>loading star</td><td>Dyne Bio</td><td>A750</td><td></td></tr><tr><td>Agarose</td><td>Sigma-Aldrich</td><td>9012-36-6</td><td></td></tr><tr><td>1 kb (+) DNA ladder marker</td><td>Enzynomics</td><td>DM003</td><td></td></tr><tr><td>Alkaline Phosphatase</td><td>Millipore</td><td>SCR004</td><td></td></tr></tbody></table>

generation of induced-pluripotent stem cells using fibroblast-like synoviocytes isolated from joints of rheumatoid arthritis patients

Mature somatic cells can be reversed into a pluripotent stem cell-like state using a defined set of reprogramming factors. Numerous studies have generated induced-Pluripotent Stem Cells (iPSCs) from various somatic cell types by transducing four Yamanaka transcription factors: Oct4, Sox2, Klf4 and c-Myc. The study of iPSCs remains at the cutting edge of biological and clinical research. In particular, patient-specific iPSCs can be used as a pioneering tool for the study of disease pathobiology, since iPSCs can be induced from the tissue of any individual. Rheumatoid arthritis (RA) is a chronic inflammatory disease, classified by the destruction of cartilage and bone structure in the joint. Synovial hyperplasia is one of the major reasons or symptoms that lead to these results in RA. Fibroblast-like Synoviocytes (FLSs) are the main component cells in the hyperplastic synovium. FLSs in the joint limitlessly proliferate, eventually invading the adjacent cartilage and bone. Currently, the hyperplastic synovium can be removed only by a surgical procedure. The removed synovium is used for RA research as a material that reflects the inflammatory condition of the joint. As a major player in the pathogenesis of RA, FLSs can be used as a material to generate and investigate the iPSCs of RA patients. In this study, we used the FLSs of a RA patient to generate iPSCs. Using a lentiviral system, we discovered that FLSs can generate RA patient-specific iPSC. The iPSCs generated from FLSs can be further used as a tool to study the pathophysiology of RA in the future.

In this study, we describe a protocol to generate iPSCs from FLSs using a lentiviral system. Figure 1A shows a simple scheme of the FLS isolation protocol. Following surgical removal of the synovium, the tissue was chopped into small pieces using surgical scissors. Collagenase was added to isolate the cells from the clumps of tissue. Cells were incubated for 14 days before further processing. Figure1B shows the morphology of the isolated ...

Watch this Scientific Journal Video about Generation of Induced-pluripotent Stem Cells Using Fibroblast-like Synoviocytes Isolated from Joints of Rheumatoid Arthritis Patients at JoVE.com

Generation of Induced-pluripotent Stem Cells Using Fibroblast-like Synoviocytes Isolated from Joints of Rheumatoid Arthritis Patients

Here we describe a protocol for generating human induced-pluripotent stem cells from patient-derived fibroblast-like synoviocytes, using a lentiviral system without feeder cells.

Mature somatic cells can be reversed into a pluripotent stem cell-like state using a defined set of reprogramming factors. Numerous studies have generated ...

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JoVE Journal

Developmental Biology

9.3K Views.  Seoul St. Mary's Hospital, Republic of Korea. Here we describe a protocol for generating human induced-pluripotent stem cells from patient-derived fibroblast-like synoviocytes, using a lentiviral system without feeder cells.

Video: Generation of Induced-pluripotent Stem Cells Using Fibroblast-like Synoviocytes Isolated from Joints of Rheumatoid Arthritis Patients

RNA-based Reprogramming of Human Primary Fibroblasts into Induced Pluripotent Stem Cells

Induced pluripotent stem cells (iPSCs) have proven to be a valuable tool to study human development and disease. Further advancing iPSCs as a regenerative therapeutic requires a safe, robust, and expedient reprogramming protocol. Here, we present a clinically relevant, step-by-step protocol for the extremely high-efficiency reprogramming of human dermal fibroblasts into iPSCs using a non-integrating approach. The core of the protocol consists of expressing pluripotency factors (SOX2, KLF4, cMYC, LIN28A, NANOG, OCT4-MyoD fusion) from in vitro transcribed messenger RNAs synthesized with modified nucleotides (modified mRNAs). The reprogramming modified mRNAs are transfected into primary fibroblasts every 48 h together with mature embryonic stem cell-specific microRNA-367/302 mimics for two weeks. The resulting iPSC colonies can then be isolated and directly expanded in feeder-free conditions. To maximize efficiency and consistency of our reprogramming protocol across fibroblast samples, we have optimized various parameters including the RNA transfection regimen, timing of transfections, culture conditions, and seeding densities. Importantly, our method generates high-quality iPSCs from most fibroblast sources, including difficult-to-reprogram diseased, aged, and/or senescent samples.

Here we describe a clinically relevant, high-efficiency, feeder-free method to reprogram human primary fibroblasts into induced pluripotent stem cells using modified mRNAs encoding reprogramming factors and mature microRNA-367/302 mimics. Also included are methods to assess reprogramming efficiency, expand clonal iPSC colonies, and confirm expression of the pluripotency marker TRA-1-60.

Induced pluripotent stem cells (iPSCs) have proven to be a valuable tool to study human development and disease. Further advancing iPSCs as a regenerative ...

Generation of Induced Pluripotent Stem Cells by Reprogramming Human Fibroblasts with the Stemgent Human TF Lentivirus Set

In 2006, Yamanaka and colleagues first demonstrated that retrovirus-mediated delivery and expression of Oct4, Sox2, c-Myc and Klf4 is capable of inducing the pluripotent state in mouse fibroblasts.1 The same group also reported the successful reprogramming of human somatic cells into induced pluripotent stem (iPS) cells using human versions of the same transcription factors delivered by retroviral vectors.2 Additionally, James Thomson et al. reported that the lentivirus-mediated co-expression of another set of factors (Oct4, Sox2, Nanog and Lin28) was capable of reprogramming human somatic cells into iPS cells.3
iPS cells are similar to ES cells in morphology, proliferation and the ability to differentiate into all tissue types of the body. Human iPS cells have a distinct advantage over ES cells as they exhibit key properties of ES cells without the ethical dilemma of embryo destruction. The generation of patient-specific iPS cells circumvents an important roadblock to personalized regenerative medicine therapies by eliminating the potential for immune rejection of non-autologous transplanted cells.
Here we demonstrate the protocol for reprogramming human fibroblast cells using the Stemgent Human TF Lentivirus Set. We also show that cells reprogrammed with this set begin to show iPS morphology four days post-transduction. Using the Stemolecule Y27632, we selected for iPS cells and observed correct morphology after three sequential rounds of colony picking and passaging. We also demonstrate that after reprogramming cells displayed the pluripotency marker AP, surface markers TRA-1-81, TRA-1-60, SSEA-4, and SSEA-3, and nuclear markers Oct4, Sox2 and Nanog.

We demonstrate the protocol for the generation of induced pluripotent stem cells from human somatic cells using lentivirus-mediated delivery of the human factors Oct4, Sox2, Nanog, and Lin28. Pluripotency was confirmed by morphology and the presence of embryonic stem (ES) cell-specific markers.

In 2006, Yamanaka and colleagues first demonstrated that retrovirus-mediated delivery and expression of Oct4, Sox2, c-Myc and Klf4 is capable of inducing ...

Biology

In Vitro Generation of Somite Derivatives from Human Induced Pluripotent Stem Cells

In response to signals such as WNTs, bone morphogenetic proteins (BMPs), and sonic hedgehog (SHH) secreted from surrounding tissues, somites (SMs) give rise to multiple cell types, including the myotome (MYO), sclerotome (SCL), dermatome (D), and syndetome (SYN), which in turn develop into skeletal muscle, axial skeleton, dorsal dermis, and axial tendon/ligament, respectively. Therefore, the generation of SMs and their derivatives from human induced pluripotent stem cells (iPSCs) is critical to obtain pluripotent stem cells (PSCs) for application in regenerative medicine and for disease research in the field of orthopedic surgery. Although the induction protocols for MYO and SCL from PSCs have been previously reported by several researchers, no study has yet demonstrated the induction of SYN and D from iPSCs. Therefore, efficient induction of fully competent SMs remains a major challenge. Here, we recapitulate human SM patterning with human iPSCs in vitro by mimicking the signaling environment during chick/mouse SM development, and report on methods of systematic induction of SM derivatives (MYO, SCL, D, and SYN) from human iPSCs under chemically defined conditions through the presomitic mesoderm (PSM) and SM states. Knowledge regarding chick/mouse&#160;SM development was successfully applied to the induction of SMs with human iPSCs. This method could be a novel tool for studying human somitogenesis and patterning without the use of embryos and for cell-based therapy and disease modeling.

We present here a protocol for the differentiation of human induced pluripotent stem cells into each somite derivative (myotome, sclerotome, dermatome, and syndetome) in chemically defined conditions, which has applications in future disease modeling and cell-based therapies in orthopedic surgery.

In response to signals such as WNTs, bone morphogenetic proteins (BMPs), and sonic hedgehog (SHH) secreted from surrounding tissues, somites (SMs) give ...

Development of Stem Cell-derived Antigen-specific Regulatory T Cells Against Autoimmunity

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic self-tolerance. Tregs represent about 5 - 10% of the mature CD4+ T cell subpopulation in mice and humans, with about 1 - 2% of those Tregs circulating in the peripheral blood. Induced pluripotent stem cells (iPSCs) can be differentiated into functional Tregs, which have a potential to be used for cell-based therapies of autoimmune diseases. Here, we present a method to develop antigen (Ag)-specific Tregs from iPSCs (i.e., iPSC-Tregs). The method is based on incorporating the transcription factor FoxP3 and an Ag-specific T cell receptor (TCR) into iPSCs and then differentiating on OP9 stromal cells expressing Notch ligands delta-like (DL) 1 and DL4. Following in vitro differentiation, the iPSC-Tregs express CD4, CD8, CD3, CD25, FoxP3, and Ag-specific TCR and are able to respond to Ag stimulation. This method has been successfully applied to cell-based therapy of autoimmune arthritis in a murine model. Adoptive transfer of these Ag-specific iPSC-Tregs into Ag-induced arthritis (AIA)-bearing mice has the ability to reduce joint inflammation and swelling and to prevent bone loss.

We present here a method to develop functional antigen (Ag)-specific regulatory T cells (Tregs) from induced pluripotent stem cells (iPSCs) for immunotherapy of autoimmune arthritis in a murine model.

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic ...

Immunology and Infection

Derivation of Adult Human Fibroblasts and their Direct Conversion into Expandable Neural Progenitor Cells

Generation of&#160;induced pluripotent stem cell (iPSCs) from adult skin fibroblasts and subsequent differentiation into somatic cells provides fascinating prospects for the derivation of autologous transplants that circumvent histocompatibility barriers. However, progression through a pluripotent state and subsequent complete differentiation into desired lineages remains a roadblock for the clinical translation of iPSC technology because of the associated neoplastic potential and genomic instability. Recently, we and others showed that somatic cells cannot only be converted into iPSCs but also into different types of multipotent somatic stem cells by using defined factors, thereby circumventing progression through the pluripotent state. In particular, the direct conversion of human fibroblasts into induced neural progenitor cells (iNPCs) heralds the possibility of a novel autologous cell source for various applications such as cell replacement, disease modeling and drug screening. Here, we describe the isolation of adult human primary fibroblasts by skin biopsy and their efficient direct conversion into iNPCs by timely restricted expression of Oct4, Sox2, Klf4, as well as c-Myc. Sox2-positive neuroepithelial colonies appear after 17 days of induction and iNPC lines can be established efficiently by monoclonal isolation and expansion. Precise adjustment of viral multiplicity of infection and supplementation of leukemia inhibitory factor during the induction phase represent critical factors to achieve conversion efficiencies of up to 0.2%. Thus far, patient-specific iNPC lines could be expanded for more than 12 passages and uniformly display morphological and molecular features of neural stem/progenitor cells, such as the expression of Nestin and Sox2. The iNPC lines can be differentiated into neurons and astrocytes as judged by staining against TUJ1 and GFAP, respectively. In conclusion, we report a robust protocol for the derivation and direct conversion of human fibroblasts into stably expandable neural progenitor cells that might provide a cellular source for biomedical applications such as autologous neural cell replacement and disease modeling.

Generation of induced pluripotent stem cells provides fascinating prospects for the derivation of autologous transplants. However, progression through a pluripotent state and laborious re-differentiation still hinders clinical translation. Here we describe the derivation of adult human fibroblasts and their direct conversion into induced neural progenitor cells and the subsequent differentiation into neural lineages.

Generation of&#160;induced pluripotent stem cell (iPSCs) from adult skin fibroblasts and subsequent differentiation into somatic cells provides ...

Neuroscience

Selecting and Isolating Colonies of Human Induced Pluripotent Stem Cells Reprogrammed from Adult Fibroblasts

Herein we present a protocol of reprogramming human adult fibroblasts into human induced pluripotent stem cells (hiPSC) using retroviral vectors encoding Oct3/4, Sox2, Klf4 and c-myc (OSKM) in the presence of sodium butyrate 1-3. We used this method to reprogram late passage (&gt;p10) human adult fibroblasts derived from Friedreich's ataxia patient (GM03665, Coriell Repository). The reprogramming approach includes highly efficient transduction protocol using repetitive centrifugation of fibroblasts in the presence of virus-containing media. The reprogrammed hiPSC colonies were identified using live immunostaining for Tra-1-81, a surface marker of pluripotent cells, separated from non-reprogrammed fibroblasts and manually passaged 4,5. These hiPSC were then transferred to Matrigel plates and grown in feeder-free conditions, directly from the reprogramming plate. Starting from the first passage, hiPSC colonies demonstrate characteristic hES-like morphology. Using this protocol more than 70% of selected colonies can be successfully expanded and established into cell lines. The established hiPSC lines displayed characteristic pluripotency markers including surface markers TRA-1-60 and SSEA-4, as well as nuclear markers Oct3/4, Sox2 and Nanog. 
The protocol presented here has been established and tested using adult fibroblasts obtained from Friedreich's ataxia patients and control individuals 6, human newborn fibroblasts, as well as human keratinocytes.

We present a protocol for efficient reprogramming of human somatic cells into human induced pluripotent stem cells (hiPSC) using retroviral vectors encoding Oct3/4, Sox2, Klf4 and c-myc (OSKM) and identification of correctly reprogrammed hiPSC by live staining with Tra-1-81 antibody.

Herein we present a protocol of reprogramming human adult fibroblasts into human induced pluripotent stem cells (hiPSC) using retroviral vectors encoding ...

Simple Generation of a High Yield Culture of Induced Neurons from Human Adult Skin Fibroblasts

Induced neurons (iNs), the product of somatic cells directly converted to neurons, are a way to obtain patient-derived neurons from tissue that is easily accessible. Through this route, mature neurons can be obtained in a matter of a few weeks. Here, we describe a straightforward and rapid one-step protocol to obtain iNs from dermal fibroblasts obtained through biopsy samples from adult human donors. We explain each step of the process, including the maintenance of the dermal fibroblasts, the freezing procedure to build a stock of the cell line, seeding of the cells for reprogramming, as well as the culture conditions during the conversion process. In addition, we describe the preparation of glass coverslips for electrophysiological recordings, long-term coating conditions, and fluorescence activated cell sorting (FACS). We also illustrate examples of the results to be expected. The protocol described here is easy to perform and can be applied to human fibroblasts derived from human skin biopsies from patients with various different diagnoses and ages. This protocol generates a sufficient amount of iNs which can be used for a wide array of biomedical applications, including disease modeling, drug screening, and target validation.

Direct neuronal reprogramming generates neurons that maintain the age of the starting somatic cell. Here, we describe a single vector-based method to generate induced neurons from dermal fibroblasts obtained from adult human donors.

Induced neurons (iNs), the product of somatic cells directly converted to neurons, are a way to obtain patient-derived neurons from tissue that is easily ...

Harnessing iPSC-Derived iTenocytes for Effective Cell-Based Therapy

Generation of Induced Pluripotent Stem Cell-Derived iTenocytes via Combined Scleraxis Overexpression and 2D Uniaxial Tension

Today&#39;s challenges in tendon and ligament repair necessitate the identification of a suitable and effective candidate for cell-based therapy to promote tendon regeneration. Mesenchymal stromal cells (MSCs) have been explored as a potential tissue engineering strategy for tendon repair. While they are multipotent and have regenerative potential in vivo, they are limited in their self-renewal capacity and exhibit phenotypic heterogeneity. Induced pluripotent stem cells (iPSCs) can circumvent these limitations due to their high self-renewal capacity and unparalleled developmental plasticity. In tenocyte development, Scleraxis (Scx) is a crucial direct molecular regulator of tendon differentiation. Additionally, mechanoregulation has been shown to be a central element guiding embryonic tendon development and healing. As such, we have developed a protocol to encapsulate the synergistic effect of biological and mechanical stimulation that may be essential for generating tenocytes. iPSCs were induced to become mesenchymal stromal cells (iMSCs) and were characterized with classic mesenchymal stromal cell markers via flow cytometry. Next, using a lentiviral vector, the iMSCs were transduced to stably overexpress SCX (iMSCSCX+). These iMSCSCX+ cells can be further matured into iTenocytes via uniaxial tensile loading using a 2D bioreactor. The resulting cells were characterized by observing the upregulation of early and late tendon markers, as well as collagen deposition. This method of generating iTenocytes can be used to assist researchers in developing a potentially unlimited off-the-shelf allogeneic cell source for tendon cell therapy applications.

Author Spotlight: Advancements in Cell and Tissue Engineering for Tendon Repair 

This article describes a procedure to produce iTenocytes by generating iPSC-derived mesenchymal stromal cells with combined overexpression of Scleraxis using a lentiviral vector and uniaxial stretching via a 2D bioreactor.

Today&#39;s challenges in tendon and ligament repair necessitate the identification of a suitable and effective candidate for cell-based therapy to ...

Bioengineering

Unveiling Inflammatory Arthritis&#58; Exploring Functions of Synovial Cells

Isolation and Culture of Primary Synovial Macrophages and Fibroblasts from Murine Arthritis Tissue

Rheumatoid arthritis is an autoimmune disease that leads to chronic inflammation of joints. Synovial macrophages and synovial fibroblasts have central roles in the pathogenesis of rheumatoid arthritis. It is important to understand the functions of both cell populations to reveal the mechanisms underlying pathological progression and remission in inflammatory arthritis. In general, in vitro experimental conditions should mimic the in vivo environment as much as possible. Primary tissue-derived cells have been used in experiments characterizing synovial fibroblasts in arthritis. In contrast, in experiments investigating the biological functions of macrophages in inflammatory arthritis, cell lines, bone marrow-derived macrophages, and blood monocyte-derived macrophages have been used. However, it is unclear whether such macrophages actually reflect the functions of tissue-resident macrophages. To obtain resident macrophages, previous protocols were modified to isolate and expand both primary macrophages and fibroblasts from synovial tissue in an inflammatory arthritis mouse model. These primary synovial cells may be useful for in vitro analysis of inflammatory arthritis.

Author Spotlight: Isolation and Culture of Primary Synovial Macrophages and Fibroblasts from Murine Arthritis Tissue  

The present study provides a modified protocol to isolate synovial macrophages and fibroblasts from murine inflammatory arthritis tissue.

Rheumatoid arthritis is an autoimmune disease that leads to chronic inflammation of joints. Synovial macrophages and synovial fibroblasts have central ...

A Cell-Based Therapy for Autoimmune Arthritis in a Murine Model

Source: Haque, M. et al., <a href="https://appjove.unicartagenaproxy.elogim.com/v/54720">Development of Stem Cell-derived Antigen-specific Regulatory T Cells Against Autoimmunity.</a>&#160;J. Vis. Exp. (2016)
This video showcases a cell-based therapy for autoimmune arthritis in mice. iPSC-derived T regulatory cells expressing ovalbumin-specific receptors are injected with methylated bovine serum albumin (mBSA) emulsified in an adjuvant. Murine antigen-presenting cells (APCs) process and present the mBSA to T cells, prompting T cell activation and migration to the knee joint&#39;s synovial membrane. Subsequent injections involve mBSA alone in the left knee and a combination of mBSA and ovalbumin in the right knee. In the left knee, the immune response to mBSA triggers arthritis, while in the right knee, T-regulatory cells interacting with ovalbumin mitigate inflammation, improving arthritis symptoms.