• Journal of Veterinary Clinics
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• v.27 no.2
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• pp.147-153
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• 2010

Bio-integration of cartilage grafts with subchondral bone is a significant clinical challenge. To date, the use of demineralized bone matrix (DBM) has been one of the most effective strategies for bone cell proliferation in vivo. Here, we investigated whether coculture of chondrocytes and DBM could serve as a single-platform system containing all the essential elements for purposive bone and cartilage induction. The aim of this study was to evaluate and compare the phenotype and proliferation of bovine chondrocytes cocultured with DBM in two different culture systems, pellet and alginate bead culture. In alginate bead culture, we observed an increase in chondrocyte number and formation of cell clusters. Typical chondrocytic phenotype was maintained for entire eight weeks. Histological analysis showed that chondrocytes maintained a typical round, plump morphology and there was a gradual increase in lacunae. Both coculture systems yielded an expanded cell population as compared to the controls (chondrocytes alone). The production of glycosaminoglycans was also increased in the coculture systems as compared to controls.

• Journal of Veterinary Clinics
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• v.32 no.3
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• pp.224-230
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• 2015

This study was designed in the fabricated poly (L-Lactic-co-${\varepsilon}$-Caprolactone) (PLCL) scaffold using chitosan-alginate hydrogel, which would be more suitable to maintain the biological and physiological functions continuing three dimensional spatial organizations for chondrocytes. As a scaffold, hydrogels alone is weak at endure complex loading within the body. In this study, we made cell hybrid scaffold constructs with poly (L-Lactic-co-${\varepsilon}$-Caprolactone) (PLCL) scaffold and hydrogels to make a three-dimensional composition of cells and extracellular matrix, which would be a mimic of a native cartilage. Using a particle leaching technique with NaCl, we fabricated a highly-elastic scaffold from PLCL with 85% porosity and $300-500{\mu}m$ pore size. A mixture of bovine chondrocytes and chitosan-alginate gel was seeded and compared with alginate as a control on the PLCL scaffold. The cell maturation, proliferation, extracellular matrix synthesis, glycosaminoglycans (sGAG) production and collagen type-II expressions were better in chondrocytes seeded in chitosan-alginate hydrogel than in alginate only. These results indicate that chondrocytes with chitosan-alginate gel on PLCL scaffolds provide an appropriate biomimetic environment for cell proliferation and matrix synthesis, which could successfully be used for cartilage repair and regeneration.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.335-339
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• 2003

The aim of this study is to optimize the monolayer cultivation of human articular chondrocytes in serum-free media. For this purpose, chondrocytes were isolated from human articular cartilage and monolayer cultures were performed in DMEM/F12 medium with 10% fetal bovine serum (FBS) or serum-free media (SFM) containing various supplements and epidermal growth factor (EGF). Western blotting analysis, RT-PCR, dimethylmethylene blue (DMB) assay were carried out to evaluate the synthesis of collagen type II (Col. II) and glycosaminoglycans (GAGs). We observed that SFM with EGF stimulated the cell growth while the amounts of synthesized GAGs and Col. II were decreased gradually. However, the Col. II mRNA level was increased when the SFM was replaced by media containing 10% FBS. This study suggests that it is possible to obtain large amount of human articular chondrocytes by short-term monolayer cultures in SFM.

• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.781-791
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• 2018

BACKGROUND: Glucosamine hydrochloride (GlcN HCl) has been shown to inhibit cell growth and matrix synthesis, but not with N-acetyl-glucosamine (GlcNAc) supplementation. This effect might be related to an inhibition of critical growth factors (GF), or to a different metabolization of the two glucosamine derivatives. The aim of the present study was to evaluate the synergy between GlcN HCl, GlcNAc, and GF on proliferation and cartilage matrix synthesis. METHOD: Bovine chondrocytes were cultivated in monolayers for 48 h and in three-dimensional (3D) chitosan scaffolds for 30 days in perfusion bioreactors. Serum-free (SF) medium was supplemented with either growth factors (GF) $TGF-{\beta}$ ($5ng\;mL^{-1}$) and IGF-I ($10ng\;mL^{-1}$), GlcN HCl or GlcNAc at 1mM each or both. Six groups were compared according to medium supplementation: (a) SF control; (b) SF + GlcN HCl; (c) SF + GlcNAc; (d) SF + GF; (e) SF + GF + GlcN HCl; and (f) SF + GF + GlcNAc. Cell proliferation, proteoglycan, collagen I (COL1), and collagen II (COL2) synthesis were evaluated. RESULTS: The two glucosamines showed opposite effects in monolayer culture: GlcN HCl significantly reduced proliferation and GlcNAc significantly augmented cellular metabolism. In the 30 days 3D culture, the GlcN HCl added to GF stimulated cell proliferation more than when compared to GF only, but the proteoglycan synthesis was smaller than GF. However, GlcNAc added to GF improved the cell proliferation and proteoglycan synthesis more than when compared to GF and GF/GlcN HCl. The synthesis of COL1 and COL2 was observed in all groups containing GF. CONCLUSION: GlcN HCl and GlcNAc increased cell growth and stimulated COL2 synthesis in long-time 3D culture. However, only GlcNAc added to GF improved proteoglycan synthesis.

• Journal of Veterinary Clinics
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• v.36 no.4
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• pp.200-206
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• 2019

This study was performed to assess the anti-inflammatory and cartilage regenerative effects of platelet-rich plasma (PRP) on canine chondrocytes. Proliferation and migration assays under both normal and lipopolysaccharide (LPS)-induced inflammatory conditions were performed with various concentrations of PRP (1% to 10%). The expression levels of genes related to osteoarthritis were evaluated in the following groups: PRP group, LPS group and LPS + PRP group. mRNA expression levels were detected using real-time polymerase chain reaction (RT-PCR). Proliferation assays showed significantly enhanced proliferation in all PRP-treated groups compared with the no serum group. Compared with 10% fetal bovine serum (FBS), PRP concentrations above 3% in the normal condition and 1% to 7% PRP in the LPS-induced inflammatory condition were found to significantly promote chondrocyte proliferation. In the normal condition, all PRP-treated groups showed significantly increased cell migration compared with the no serum group. Chondrocyte migration was decreased with LPS-induced inflammation, but PRP treatment resulted in significantly enhanced migration compared with the other groups in this condition. According to RT-PCR, the LPS + PRP group showed significantly higher levels of COL1A1, IL-6, aggrecan and lower levels of $TNF-{\alpha}$, MMP-1, MMP-3 mRNA expression compared to the LPS group. The results of this study suggest that PRP application can enhance the proliferation and migration of canine chondrocytes and improve canine articular cartilage regeneration.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.6
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• pp.343-353
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• 2012

Objectives: This aim of this study was to effectively isolate mesenchymal stem cells (hSMSCs) from human submandibular skin tissues (termed hSMSCs) and evaluate their characteristics. These hSMSCs were then chemically induced to the neuronal lineage and analyzed for their neurogenic characteristics in vitro. Materials and Methods: Submandibular skin tissues were harvested from four adult patients and cultured in stem cell media. Isolated hSMSCs were evaluated for their multipotency and other stem cell characteristics. These cells were differentiated into neuronal cells with a chemical induction protocol. During the neuronal induction of hSMSCs, morphological changes and the expression of neuron-specific proteins (by fluorescence-activated cell sorting [FACS]) were evaluated. Results: The hSMSCs showed plate-adherence, fibroblast-like growth, expression of the stem-cell transcription factors Oct 4 and Nanog, and positive staining for mesenchymal stem cell (MSC) marker proteins (CD29, CD44, CD90, CD105, and vimentin) and a neural precursor marker (nestin). Moreover, the hSMSCs in this study were successfully differentiated into multiple mesenchymal lineages, including osteocytes, adipocytes, and chondrocytes. Neuron-like cell morphology and various neural markers were highly visible six hours after the neuronal induction of hSMSCs, but their neuron-like characteristics disappeared over time (24-48 hrs). Interestingly, when the chemical induction medium was changed to Dulbecco's Modified Eagle Medium (DMEM) supplemented with fetal bovine serum (FBS), the differentiated cells returned to their hSMSC morphology, and their cell number increased. These results indicate that chemically induced neuron-like cells should not be considered true nerve cells. Conclusion: Isolated hSMSCs have MSC characteristics and express a neural precursor marker, suggesting that human skin is a source of stem cells. However, the in vitro chemical neuronal induction of hSMSC does not produce long-lasting nerve cells and more studies are required before their use in nerve-tissue transplants.