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Xingdong Zhang - One of the best experts on this subject based on the ideXlab platform.
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Correction: The role of Sox9 in Collagen Hydrogel-mediated chondrogenic differentiation of adult mesenchymal stem cells (MSCs).
Biomaterials science, 2019Co-Authors: Xianfang Jiang, Xianyuan Huang, Tongmeng Jiang, Li Zheng, Jinmin Zhao, Xingdong ZhangAbstract:Correction for 'The role of Sox9 in Collagen Hydrogel-mediated chondrogenic differentiation of adult mesenchymal stem cells (MSCs)' by Xianfang Jiang, et al., Biomater. Sci., 2018, 6, 1556-1568.
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Methacrylamide-modified Collagen Hydrogel with improved anti-actin-mediated matrix contraction behavior.
Journal of materials chemistry. B, 2018Co-Authors: Ke Yang, Likun Guo, Jing Sun, Dan Wei, Jirong Yang, Hongsong Fan, Zhenzhen Guo, Yanfei Tan, Hongrong Luo, Xingdong ZhangAbstract:For an ideal biomimetic microenvironment to realize reliable cartilage regeneration, the ability to induce mesenchymal stem cell (MSCs) differentiation along the chondrogenic lineage and prevent further dedifferentiation is expected. With native bioactivity, Collagen has been proved to be preferential for inducing the chondrogenic differentiation of MSCs. However, the phenotypic maintenance of differentiated chondrocytes in a Collagen matrix is still a challenge. Actin traction, which causes drastic contraction of the Collagen matrix, is frequently observed and might be an important factor that affects cell fates including chondrogenic differentiation and phenotypic maintenance. In this study, photochemical modification was applied to acquire Collagen Hydrogels with improved mechanical strength and creep behavior. Accompanied by inherited bioactivity, the photo-crosslinked Collagen Hydrogel well supported the actin cytoskeleton functionalization while resisting the actin-mediated matrix contraction. Benefitting from this, the Hydrogel system promoted MSCs proliferation and chondrogenic differentiation, and more importantly, prevented further dedifferentiation. By exploring the mesenchymal development-related signal transduction markers, it was revealed that the promoted chondrogenesis was achieved through inhibiting the over-expression of MAPK and Wnt/β-catenin signaling pathways that up-regulated dedifferentiated gene expression. The strategy of applying the Hydrogel system to cartilage regeneration is foreseeable based on the positive heterotopic and orthotopic chondrogenic differentiation.
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icariin conjugated hyaluronic acid Collagen Hydrogel for osteochondral interface restoration
Acta Biomaterialia, 2018Co-Authors: Jirong Yang, Yujiang Fan, Tun Yuan, Qiguang Wang, Yumei Xiao, Yanbo Liu, Lan Wang, Xingdong ZhangAbstract:Abstract Over the past decades, numerous tissue-engineered constructs have been investigated for the osteochondral repair. However, it still remains a challenge to regenerate the functionalized calcified layer. In this study, the potential of icariin (Ica) conjugated hyaluronic acid/Collagen (Ica-HA/Col) Hydrogel to promote the osteochondral interface restoration was investigated. Compared with HA/Col Hydrogel, Ica-HA/Col Hydrogel simultaneously facilitated chondrogenesis and osteogenesis in vitro. The cells encapsulated in Ica-HA/Col Hydrogel tended to aggregate into bigger clusters. The chondrogenic genes’ expression level was remarkably up-regulated, and the matrix synthesis of sGAG and type II Collagen was significantly enhanced. Similarly, the osteogenic genes, including RUNX2, ALP, and OCN were also up-regulated at early stage. Consequently, more calcium deposition was observed in the Ica-HA/Col Hydrogel construct. Moreover, the gene expression and matrix synthesis of type X Collagen, an important marker for the formation of calcified layer; were significantly higher in the Ica-HA/Col Hydrogel. Furthermore, the in vivo study showed that Ica-HA/Col constructs facilitated the reconstruction of osteochondral interface in rabbit subchondral defects. In the Ica-HA/Col group, the neo-cartilage layer contained more type II Collagen and the newly formed subchondral bone deposited more abundant type I Collagen. Overall, the results indicated that Ica-HA/Col Hydrogel might be a promising scaffold to reconstruct an osteochondral interface, therefore promoting restoring of osteochondral defect. Statement of Significance The osteochondral defect restoration not only involves the repair of damaged cartilage and the subchondral bone, but also the reconstruction of osteochondral interface (the functional calcified layer). The calcified layer regeneration is essential for integrative and functional osteochondral repair. Over the past decade, numerous tissue engineered constructs have been investigated for the osteochondral repair. However, it still remains a challenge to regenerate a functionalized calcified layer. The present study demonstrates that Ica-HA/Col Hydrogel facilitates deposition of matrix related to calcified layer in mixed chondrogenic/osteogenic inductive media and restoration of osteochondral defect in vivo. Since, Ica-HA/Col Hydrogel as is cheaper, easier and more efficient, it might be a desired scaffold for the osteochondral defects restoration.
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the role of sox9 in Collagen Hydrogel mediated chondrogenic differentiation of adult mesenchymal stem cells mscs
Biomaterials Science, 2018Co-Authors: Xianfang Jiang, Xianyuan Huang, Tongmeng Jiang, Li Zheng, Jinmin Zhao, Xingdong ZhangAbstract:Sox9 is a transcription factor that regulates chondrogenesis, but its role in the chondrogenic differentiation of mesenchymal stem cells (MSCs) triggered by materials is poorly understood. In this study, we investigated the effect of Sox9 interference on Collagen-induced chondrogenesis and further Collagen-based therapies for cartilage defects. In this paper, MSCs were infected with a vector carrying the Sox9 promoter and related markers were detected. A lentivirus-mediated vector targeting the silencing of the Sox9 gene was used in bone marrow-derived MSCs prior to being encapsulated in a Collagen Hydrogel. The Collagen Hydrogel as a sole inducer was also compared with transforming growth factor-β1 (TGF-β1). Before being implanted into the articular cartilage defect in rats, the cell-Hydrogel pellets were cultured in vitro for 14 days. The effect of Sox9 transfection on cell proliferation was evaluated by measuring the total DNA content. Safranin-O staining and a biochemistry assay were performed to assess the synthesis and secretion of glycosaminoglycan (GAG) of MSCs. The real-time fluorescent quantitative polymerase chain reaction (RT-PCR) was performed to detect the gene expression levels of Col1a1, Col2a1, Acan and Sox9. The protein expression of Collagen type II and Collagen type I was analyzed by immunohistochemical analysis. Collagen alone significantly increased the luciferase activity of the Sox9 promoter, which was in parallel with the upregulation of cartilage specific markers. In vitro, the chondrogenic differentiation ability of MSCs was greatly inhibited after Sox9 interference, both in the Collagen and TGF-β1-induced groups. In vivo, a further study showed that cartilage regeneration was arrested by using transfected MSCs with an injectable Collagen gel or induced by TGF-β1. The results indicated that Collagen may mediate Sox9 expression by providing a biomimetic microenvironment favoring cell condensation prior to chondrogenesis. The role of Sox9 regulation by materials is similar to that by growth factors, suggesting that well-designed scaffolds may replace growth factors in chondrogenesis. Thus, interventions targeting Sox9 may help improve articular cartilage repair.
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Fast fabrication of stable cartilage-like tissue using Collagen Hydrogel microsphere culture
Journal of materials chemistry. B, 2017Co-Authors: Jun Liu, Yujiang Fan, Yafang Chen, Hanxu Cai, Hai Lin, Yong Sun, Jie Liang, Qiguang Wang, Xingdong ZhangAbstract:Mesenchymal stem cells (MSCs) had been increasingly regarded as a potent cell source for cartilage repair. However, due to the instability of MSC-derived chondrocyte phenotype and ossification of the synthesised cartilage matrix, regenerating a stable cartilage tissue by MSCs is still challenging. The fate of chondrogenesis from MSCs is regulated by their local microenvironment, which is of vital importance to the cell behaviours, chondrogenic phenotype and matrix synthesis. In this study, we fabricated cartilage-like tissues by the chondrogenesis of MSC in three different microenvironments, including cell pellets, Collagen Hydrogel bulk (CHB) and Collagen Hydrogel microspheres (CHMs) in vitro. After 15 days in culture, the cell number was increased to 472.6% in CHMs, compared to a 58.6% decrease in CHB and a 46.6% decrease in pellets; resulting in a 230% increase in CHM size, but a 36.8% decrease in CHB and only a 20.1% increase in pellets. Histological staining demonstrated a more intensive but less homogeneous glycosaminoglycan (GAG) pattern in pellets than in CHMs. The outer area of CHB showed a stronger GAG staining than its inner area from day 5 to day 15, but the staining was weaker than that in both pellets and CHMs. The PCR results showed that CHMs achieved a significantly higher chondrogenic gene (AGG, COL2A1, SOX9) expression and a lower hypertrophic gene (COL10A1) expression than pellets and CHB, suggesting a better chondrogenic differentiation potential with a more stable phenotype in CHMs. In summary, this study highlights the advantages of CHM microenvironments over those of CHB and pellets by a better mimicking of the natural MSC proliferation process and enhancing mass exchange in vitro. The CHM culture demonstrated potential to fabricate stable cartilage-like tissue in MSC based cartilage tissue regeneration.
Thorsten Guhring - One of the best experts on this subject based on the ideXlab platform.
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Injection of a polymerized hyaluronic acid/Collagen Hydrogel matrix in an in vivo porcine disc degeneration model
European Spine Journal, 2012Co-Authors: Georg W Omlor, Andreas G Nerlich, T. Bruckner, W Richter, M. Pfeiffer, H. Lorenz, Thorsten GuhringAbstract:Introduction Disc degeneration and re-herniation after nucleotomy procedures are common problems. Simultaneous application of hyaluronic acid (HA)-based matrix has been proposed to limit disc degeneration. This, however, is hampered by loss of the substituted matrix out of the disc. Hence, in situ polymerization of the injected matrix with ultraviolet light (UVL) directly used after injection may be useful. Therefore, this study evaluates a new HA/Collagen Hydrogel matrix with in situ polymerization after implantation in an established porcine nucleotomy model. Materials and methods 12 mature minipigs were used. A total of 60 lumbar discs were analyzed. 36 discs underwent partial nucleotomy with a 16G biopsy needle. Of those, 24 discs received matrix (porcine nucleus pulposus Collagenous scaffold component and chemically modified HA) which was in situ polymerized using UVL immediately after transplantation. 12 nucleotomized discs and 24 non-nucleotomized discs served as controls. After 24 weeks, animals were killed. X-rays, MRIs, histology, and gene expression analysis were done. Results Disc height was reduced equally after sole nucleotomy and nucleotomy with HA treatment and in MRIs signal intensity decreased. For both nucleotomy groups, the nucleus histo-degeneration score showed a significant increase compared to controls. In histology, HA treatment resulted in more scarring and inflammation in the annulus. Gene expression of catabolic MMPs was up-regulated, whereas IFN-gamma, IL-6, and IL-1b were unchanged. Conclusion Although nucleotomy and administration of the implant material did not cause generalized inflammation of the disc, localized annular damage with annulus inflammation and scarring resulted in detrimental degenerative disc changes. As a result, therapeutic strategies should strongly focus on the prevention of annular damage or techniques for annular repair to remain disc integrity.
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Injection of a polymerized hyaluronic acid/Collagen Hydrogel matrix in an in vivo porcine disc degeneration model
European Spine Journal, 2012Co-Authors: Georg W Omlor, Andreas G Nerlich, T. Bruckner, W Richter, M. Pfeiffer, H. Lorenz, Thorsten GuhringAbstract:Introduction Disc degeneration and re-herniation after nucleotomy procedures are common problems. Simultaneous application of hyaluronic acid (HA)-based matrix has been proposed to limit disc degeneration. This, however, is hampered by loss of the substituted matrix out of the disc. Hence, in situ polymerization of the injected matrix with ultraviolet light (UVL) directly used after injection may be useful. Therefore, this study evaluates a new HA/Collagen Hydrogel matrix with in situ polymerization after implantation in an established porcine nucleotomy model.
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injection of a polymerized hyaluronic acid Collagen Hydrogel matrix in an in vivo porcine disc degeneration model
European Spine Journal, 2012Co-Authors: Georg W Omlor, Andreas G Nerlich, T. Bruckner, W Richter, M. Pfeiffer, H. Lorenz, Thorsten GuhringAbstract:Introduction Disc degeneration and re-herniation after nucleotomy procedures are common problems. Simultaneous application of hyaluronic acid (HA)-based matrix has been proposed to limit disc degeneration. This, however, is hampered by loss of the substituted matrix out of the disc. Hence, in situ polymerization of the injected matrix with ultraviolet light (UVL) directly used after injection may be useful. Therefore, this study evaluates a new HA/Collagen Hydrogel matrix with in situ polymerization after implantation in an established porcine nucleotomy model.
Ulrich Noth - One of the best experts on this subject based on the ideXlab platform.
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a prospective multicenter study on the outcome of type i Collagen Hydrogel based autologous chondrocyte implantation cares for the repair of articular cartilage defects in the knee
American Journal of Sports Medicine, 2011Co-Authors: Ulrich Schneide, Lars Rackwitz, S Andereya, Sebastia Siebenlis, Floria Fensky, Johannes C Reiche, Ingo Loe, Thomas Arthel, Maximilia Rude, Ulrich NothAbstract:Background: The Cartilage Regeneration System (CaReS) is a novel matrix-associated autologous chondrocyte implantation (ACI) technique for the treatment of chondral and osteochondral lesions (Outerbridge grades III and IV). For this technology, no expansion of the chondrocytes in a monolayer culture is needed, and a homogeneous cell distribution within the gel is guaranteed.Purpose: To report a prospective multicenter study of matrix-associated ACI of the knee using a new type I Collagen Hydrogel (CaReS).Study Design: Case series; Level of evidence, 4.Methods: From 2003 to 2008, 116 patients (49 women and 67 men; mean age, 32.5 ± 8.9 years) had CaReS implantation of the knee in 9 different centers. On the basis of the International Cartilage Repair Society (ICRS) Cartilage Injury Evaluation Package 2000, the International Knee Documentation Committee (IKDC) score, pain score (visual analog scale [VAS]), SF-36 score, overall treatment satisfaction and the IKDC functional status were evaluated. Patient foll...
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a prospective multicenter study on the outcome of type i Collagen Hydrogel based autologous chondrocyte implantation cares for the repair of articular cartilage defects in the knee
American Journal of Sports Medicine, 2011Co-Authors: U Schneider, Lars Rackwitz, S Andereya, Floria Fensky, Sebastian Siebenlist, Johannes C Reichert, Ingo Loer, Thomas Barthel, Maximilian Rudert, Ulrich NothAbstract:Background: The Cartilage Regeneration System (CaReS) is a novel matrix-associated autologous chondrocyte implantation (ACI) technique for the treatment of chondral and osteochondral lesions (Outerbridge grades III and IV). For this technology, no expansion of the chondrocytes in a monolayer culture is needed, and a homogeneous cell distribution within the gel is guaranteed.Purpose: To report a prospective multicenter study of matrix-associated ACI of the knee using a new type I Collagen Hydrogel (CaReS).Study Design: Case series; Level of evidence, 4.Methods: From 2003 to 2008, 116 patients (49 women and 67 men; mean age, 32.5 ± 8.9 years) had CaReS implantation of the knee in 9 different centers. On the basis of the International Cartilage Repair Society (ICRS) Cartilage Injury Evaluation Package 2000, the International Knee Documentation Committee (IKDC) score, pain score (visual analog scale [VAS]), SF-36 score, overall treatment satisfaction and the IKDC functional status were evaluated. Patient foll...
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a prospective multicenter study on the outcome of type i Collagen Hydrogel based autologous chondrocyte implantation cares for the repair of articular cartilage defects in the knee
American Journal of Sports Medicine, 2011Co-Authors: U Schneider, Lars Rackwitz, S Andereya, Floria Fensky, Sebastian Siebenlist, Johannes C Reichert, Ingo Loer, Thomas Barthel, Maximilian Rudert, Ulrich NothAbstract:BACKGROUND: The Cartilage Regeneration System (CaReS) is a novel matrix-associated autologous chondrocyte implantation (ACI) technique for the treatment of chondral and osteochondral lesions (Outerbridge grades III and IV). For this technology, no expansion of the chondrocytes in a monolayer culture is needed, and a homogeneous cell distribution within the gel is guaranteed. PURPOSE: To report a prospective multicenter study of matrix-associated ACI of the knee using a new type I Collagen Hydrogel (CaReS). STUDY DESIGN: Case series; Level of evidence, 4. METHODS: From 2003 to 2008, 116 patients (49 women and 67 men; mean age, 32.5 ± 8.9 years) had CaReS implantation of the knee in 9 different centers. On the basis of the International Cartilage Repair Society (ICRS) Cartilage Injury Evaluation Package 2000, the International Knee Documentation Committee (IKDC) score, pain score (visual analog scale [VAS]), SF-36 score, overall treatment satisfaction and the IKDC functional status were evaluated. Patient follow-up was performed at 3, 6, and 12 months after surgery and annually thereafter. Mean follow-up was 30.2 ± 17.4 months (range, 12-60 months). There were 67 defects of the medial condyle, 14 of the lateral, 22 of the patella/trochlea, and 3 of the tibial plateau, and 10 patients had 2 lesions. The mean defect size was 5.4 ± 2.4 cm(2). Thirty percent of the defects were 4 cm(2). RESULTS: The IKDC score improved significantly from 42.4 ± 13.8 preoperatively to 70.5 ± 18.7 (P < .001) at latest follow-up. Global pain level significantly decreased (P < .001) from 6.7 ± 2.2 preoperatively to 3.2 ± 3.1 at latest follow-up. There also was a significant increase of both components of the SF-36 score. The overall treatment satisfaction was judged as very good or good in 88% by the surgeon and 80% by the patient. The IKDC functional knee status was grade I in 23.4%, II in 56.3%, III in 17.2%, and IV in 3.1% of the patients. CONCLUSION: Matrix-associated ACI employing the CaReS technology for the treatment of chondral or osteochondral defects of the knee is a safe and clinically effective treatment that yields significant functional improvement and improvement in pain level. However, further investigation is necessary to determine the long-term viability and clinical outcome of this procedure.
Tun Yuan - One of the best experts on this subject based on the ideXlab platform.
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icariin conjugated hyaluronic acid Collagen Hydrogel for osteochondral interface restoration
Acta Biomaterialia, 2018Co-Authors: Jirong Yang, Yujiang Fan, Tun Yuan, Qiguang Wang, Yumei Xiao, Yanbo Liu, Lan Wang, Xingdong ZhangAbstract:Abstract Over the past decades, numerous tissue-engineered constructs have been investigated for the osteochondral repair. However, it still remains a challenge to regenerate the functionalized calcified layer. In this study, the potential of icariin (Ica) conjugated hyaluronic acid/Collagen (Ica-HA/Col) Hydrogel to promote the osteochondral interface restoration was investigated. Compared with HA/Col Hydrogel, Ica-HA/Col Hydrogel simultaneously facilitated chondrogenesis and osteogenesis in vitro. The cells encapsulated in Ica-HA/Col Hydrogel tended to aggregate into bigger clusters. The chondrogenic genes’ expression level was remarkably up-regulated, and the matrix synthesis of sGAG and type II Collagen was significantly enhanced. Similarly, the osteogenic genes, including RUNX2, ALP, and OCN were also up-regulated at early stage. Consequently, more calcium deposition was observed in the Ica-HA/Col Hydrogel construct. Moreover, the gene expression and matrix synthesis of type X Collagen, an important marker for the formation of calcified layer; were significantly higher in the Ica-HA/Col Hydrogel. Furthermore, the in vivo study showed that Ica-HA/Col constructs facilitated the reconstruction of osteochondral interface in rabbit subchondral defects. In the Ica-HA/Col group, the neo-cartilage layer contained more type II Collagen and the newly formed subchondral bone deposited more abundant type I Collagen. Overall, the results indicated that Ica-HA/Col Hydrogel might be a promising scaffold to reconstruct an osteochondral interface, therefore promoting restoring of osteochondral defect. Statement of Significance The osteochondral defect restoration not only involves the repair of damaged cartilage and the subchondral bone, but also the reconstruction of osteochondral interface (the functional calcified layer). The calcified layer regeneration is essential for integrative and functional osteochondral repair. Over the past decade, numerous tissue engineered constructs have been investigated for the osteochondral repair. However, it still remains a challenge to regenerate a functionalized calcified layer. The present study demonstrates that Ica-HA/Col Hydrogel facilitates deposition of matrix related to calcified layer in mixed chondrogenic/osteogenic inductive media and restoration of osteochondral defect in vivo. Since, Ica-HA/Col Hydrogel as is cheaper, easier and more efficient, it might be a desired scaffold for the osteochondral defects restoration.
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conjugated icariin promotes tissue engineered cartilage formation in hyaluronic acid Collagen Hydrogel
Process Biochemistry, 2015Co-Authors: Tun Yuan, Yujiang Fan, Jirong Yang, Lei Zhang, Yumei Xiao, Xingdong ZhangAbstract:Abstract Bioactive factors were added into Hydrogel scaffolds to overcome the shortcomings of their low cell affinity and poor bioactivity, as well as limited cell spreading ability for anchorage-dependent cells such as chondrocytes, MSCs, etc. But the direct addition of these bioactive factors may lead to high cost, short effective time and possible side effects etc. In this study, a flavonol glycosides named icariin was chemically conjugated to hyaluronic acid/Collagen Hydrogel (HA–Ica/Col). It was observed that the presence of HA–Ica macromolecules had no significant effect on mechanical and degradation property of the Hydrogel. However, the fixed icariin in HA–Ica/Col Hydrogel gradually released, effectively maintained the chondrocytes morphology and promoted the biosynthesis of cartilage matrix. The gene expressions of sox9, aggrecan, type II Collagen (Col II) of the seeded chondrocytes were obviously increased. The productions of glycosaminoglycan (GAG) and Col II in HA–Ica/Col Hydrogel were much more. The formation of new cartilage tissue in HA–Ica/Col Hydrogel was obviously better than which in Hydrogel without fixed icariin. These results suggested that integrating icariin into scaffold by chemical conjugation will increase the quality of formed cartilage, and may decrease the risks of excessive release, therefore is valuable in cartilage tissue engineering.
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Collagen Hydrogel as an immunomodulatory scaffold in cartilage tissue engineering
Journal of Biomedical Materials Research Part B, 2014Co-Authors: Tun Yuan, Yujiang Fan, Li Zhang, Jie Liang, Hongsong Fan, Xingdong ZhangAbstract:A Collagen type I Hydrogel was constructed and used as the scaffold for cartilage tissue engineering. Neonatal rabbit chondrocytes were seeded into the Hydrogel, and the constructs were cultured in vitro for 7, 14, and 28 days. The immunomodulatory effect of the Hydrogel on seeded chondrocytes was carefully investigated. The expressions of major histocompatibility complex classes I and II of seeded chondrocytes increased with the time, which indicated that the immunogenicity also increased with the time. Meanwhile, the properly designed Collagen type I Hydrogel could prompt the chondrogenesis of engineered cartilage. The extracellular matrix (ECM) synthesis ability of seeded chondrocytes and the accumulated ECM in the constructs continuously increased with the culture time. Both the isolation and protection, which come from formed ECM and Hydrogel scaffold, can effectively control the adverse immunogenicity of seeded chondrocytes and even help to lessen the immunogenicity of the whole engineered cartilage. As the result, the levels of mixed lymphocyte chondrocyte reactions of seed cells and the constructs decreased gradually. The stimulation on allogeneic lymphocytes of the whole constructs was obviously lower than that of the retrieved cells from the constructs. Therefore, properly designed Collagen type I Hydrogel can give certain immunogenicity-reducing effects on engineered cartilage based on chondrocytes, and it may be a potential immunomodulatory biomaterial in tissue engineering.
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An in vitro study of Collagen Hydrogel to induce the chondrogenic differentiation of mesenchymal stem cells
Journal of Biomedical Materials Research Part A, 2012Co-Authors: Li Zhang, Tun Yuan, Xingdong ZhangAbstract:It is controversial whether a biomaterial itself, rather than addition of any exogenous growth factor, could induce mesenchymal stem cells (MSCs) to differentiate into chondrogenic lineage, further to regenerate cartilage. Previous studies have shown that Collagen-based Hydrogel could induce MSCs to differentiate into chondrocytes in vivo but the in vitro studies only have a few reports. The evidence that biomaterials could induce chondrogenesis is not adequate. In this study, we tried to address whether type I Collagen Hydrogel has chondro-inductive capability in vitro and how this scaffold induces MSCs to generate cartilage tissue without exogenous growth factors in the culture medium. We encapsulated neonatal rabbit bone marrow mesenchymal stem cells (BMSCs) in type I Collagen Hydrogel homogeneously or implanted cell aggregates in Hydrogel, and cultured them in nonchondrogenic inductive media. After at least 28 days culture, cells in the homogeneous group were tending to chondrogenic differentiation while cell density was high, and cells in the aggregate group have almost gone through chondrogenesis and formed neo-cartilage tissue with abundant specific extracellular matrix (ECM) deposition. These results indicate Collagen Hydrogel has inherent inductivity for the chondrogenic differentiation of BMSCs, and the optimum specification and tissue formation were accompanied with local high cell density. This research suggests a feasible strategy to induce the chondro differentiation of BMSCs independent of exogenous growth factors, which may greatly contribute to clinical cartilage regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A: 2717–2725, 2012.
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An in vitro study of Collagen Hydrogel to induce the chondrogenic differentiation of mesenchymal stem cells
Journal of biomedical materials research. Part A, 2012Co-Authors: Li Zhang, Likun Guo, Tun Yuan, Xingdong ZhangAbstract:It is controversial whether a biomaterial itself, rather than addition of any exogenous growth factor, could induce mesenchymal stem cells (MSCs) to differentiate into chondrogenic lineage, further to regenerate cartilage. Previous studies have shown that Collagen-based Hydrogel could induce MSCs to differentiate into chondrocytes in vivo but the in vitro studies only have a few reports. The evidence that biomaterials could induce chondrogenesis is not adequate. In this study, we tried to address whether type I Collagen Hydrogel has chondro-inductive capability in vitro and how this scaffold induces MSCs to generate cartilage tissue without exogenous growth factors in the culture medium. We encapsulated neonatal rabbit bone marrow mesenchymal stem cells (BMSCs) in type I Collagen Hydrogel homogeneously or implanted cell aggregates in Hydrogel, and cultured them in nonchondrogenic inductive media. After at least 28 days culture, cells in the homogeneous group were tending to chondrogenic differentiation while cell density was high, and cells in the aggregate group have almost gone through chondrogenesis and formed neo-cartilage tissue with abundant specific extracellular matrix (ECM) deposition. These results indicate Collagen Hydrogel has inherent inductivity for the chondrogenic differentiation of BMSCs, and the optimum specification and tissue formation were accompanied with local high cell density. This research suggests a feasible strategy to induce the chondro differentiation of BMSCs independent of exogenous growth factors, which may greatly contribute to clinical cartilage regeneration.
Georg W Omlor - One of the best experts on this subject based on the ideXlab platform.
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Injection of a polymerized hyaluronic acid/Collagen Hydrogel matrix in an in vivo porcine disc degeneration model
European Spine Journal, 2012Co-Authors: Georg W Omlor, Andreas G Nerlich, T. Bruckner, W Richter, M. Pfeiffer, H. Lorenz, Thorsten GuhringAbstract:Introduction Disc degeneration and re-herniation after nucleotomy procedures are common problems. Simultaneous application of hyaluronic acid (HA)-based matrix has been proposed to limit disc degeneration. This, however, is hampered by loss of the substituted matrix out of the disc. Hence, in situ polymerization of the injected matrix with ultraviolet light (UVL) directly used after injection may be useful. Therefore, this study evaluates a new HA/Collagen Hydrogel matrix with in situ polymerization after implantation in an established porcine nucleotomy model. Materials and methods 12 mature minipigs were used. A total of 60 lumbar discs were analyzed. 36 discs underwent partial nucleotomy with a 16G biopsy needle. Of those, 24 discs received matrix (porcine nucleus pulposus Collagenous scaffold component and chemically modified HA) which was in situ polymerized using UVL immediately after transplantation. 12 nucleotomized discs and 24 non-nucleotomized discs served as controls. After 24 weeks, animals were killed. X-rays, MRIs, histology, and gene expression analysis were done. Results Disc height was reduced equally after sole nucleotomy and nucleotomy with HA treatment and in MRIs signal intensity decreased. For both nucleotomy groups, the nucleus histo-degeneration score showed a significant increase compared to controls. In histology, HA treatment resulted in more scarring and inflammation in the annulus. Gene expression of catabolic MMPs was up-regulated, whereas IFN-gamma, IL-6, and IL-1b were unchanged. Conclusion Although nucleotomy and administration of the implant material did not cause generalized inflammation of the disc, localized annular damage with annulus inflammation and scarring resulted in detrimental degenerative disc changes. As a result, therapeutic strategies should strongly focus on the prevention of annular damage or techniques for annular repair to remain disc integrity.
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Injection of a polymerized hyaluronic acid/Collagen Hydrogel matrix in an in vivo porcine disc degeneration model
European Spine Journal, 2012Co-Authors: Georg W Omlor, Andreas G Nerlich, T. Bruckner, W Richter, M. Pfeiffer, H. Lorenz, Thorsten GuhringAbstract:Introduction Disc degeneration and re-herniation after nucleotomy procedures are common problems. Simultaneous application of hyaluronic acid (HA)-based matrix has been proposed to limit disc degeneration. This, however, is hampered by loss of the substituted matrix out of the disc. Hence, in situ polymerization of the injected matrix with ultraviolet light (UVL) directly used after injection may be useful. Therefore, this study evaluates a new HA/Collagen Hydrogel matrix with in situ polymerization after implantation in an established porcine nucleotomy model.
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injection of a polymerized hyaluronic acid Collagen Hydrogel matrix in an in vivo porcine disc degeneration model
European Spine Journal, 2012Co-Authors: Georg W Omlor, Andreas G Nerlich, T. Bruckner, W Richter, M. Pfeiffer, H. Lorenz, Thorsten GuhringAbstract:Introduction Disc degeneration and re-herniation after nucleotomy procedures are common problems. Simultaneous application of hyaluronic acid (HA)-based matrix has been proposed to limit disc degeneration. This, however, is hampered by loss of the substituted matrix out of the disc. Hence, in situ polymerization of the injected matrix with ultraviolet light (UVL) directly used after injection may be useful. Therefore, this study evaluates a new HA/Collagen Hydrogel matrix with in situ polymerization after implantation in an established porcine nucleotomy model.