1
|
Choi SH, Lee K, Han H, Mo H, Jung H, Ryu Y, Nam Y, Rim YA, Ju JH. Prochondrogenic effect of decellularized extracellular matrix secreted from human induced pluripotent stem cell-derived chondrocytes. Acta Biomater 2023:S1742-7061(23)00317-3. [PMID: 37295627 DOI: 10.1016/j.actbio.2023.05.052] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 05/18/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023]
Abstract
Cartilage is mainly composed of chondrocytes and the extracellular matrix (ECM), which exchange important biochemical and biomechanical signals necessary for differentiation and homeostasis. Human articular cartilage has a low ability for regeneration because it lacks blood vessels, nerves, and lymphatic vessels. Currently, cell therapeutics, including stem cells, provide a promising strategy for cartilage regeneration and treatment; however, there are various hurdles to overcome, such as immune rejection and teratoma formation. In this study, we assessed the applicability of the stem cell-derived chondrocyte ECM for cartilage regeneration. Human induced pluripotent stem cell (hiPSC)-derived chondrocytes (iChondrocytes) were differentiated, and decellularized ECM (dECM) was successfully isolated from cultured chondrocytes. Isolated dECM enhanced in vitro chondrogenesis of iPSCs when recellularized. Implanted dECM also restored osteochondral defects in a rat osteoarthritis model. A possible association with the glycogen synthase kinase-3 beta (GSK3β) pathway demonstrated the fate-determining importance of dECM in regulating cell differentiation. Collectively, we suggested the prochondrogenic effect of hiPSC-derived cartilage-like dECM and offered a promising approach as a non-cellular therapeutic for articular cartilage reconstruction without cell transplantation. STATEMENT OF SIGNIFICANCE: Human articular cartilage has low ability for regeneration and cell culture-based therapeutics could aid cartilage regeneration. Yet, the applicability of human induced pluripotent stem cell-derived chondrocyte (iChondrocyte) extracellular matrix (ECM) has not been elucidated. Therefore, we first differentiated iChondrocytes and isolated the secreted ECM by decellularization. Recellularization was performed to confirm the pro-chondrogenic effect of the decellularized ECM (dECM). In addition, we confirmed the possibility of cartilage repair by transplanting the dECM into the cartilage defect in osteochondral defect rat knee joint. We believe that our proof-of-concept study will serve as a basis for investigating the potential of dECM obtained from iPSC-derived differentiated cells as a non-cellular resource for tissue regeneration and other future applications.
Collapse
Affiliation(s)
- Si Hwa Choi
- Catholic iPSC Research Center, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea
| | | | - Heeju Han
- Catholic iPSC Research Center, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea
| | - Hyunkyung Mo
- Catholic iPSC Research Center, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea
| | | | - YoungWoo Ryu
- Catholic iPSC Research Center, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea
| | | | - Yeri Alice Rim
- Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea.
| | - Ji Hyeon Ju
- Catholic iPSC Research Center, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea; YiPSCELL, Inc., Seoul, South Korea; Division of Rheumatology, Department of Internal Medicine, Seoul St. Mary's Hospital, Institute of Medical Science, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
| |
Collapse
|
2
|
Tonomura H, Nagae M, Takatori R, Ishibashi H, Itsuji T, Takahashi K. The Potential Role of Hepatocyte Growth Factor in Degenerative Disorders of the Synovial Joint and Spine. Int J Mol Sci 2020; 21:ijms21228717. [PMID: 33218127 PMCID: PMC7698933 DOI: 10.3390/ijms21228717] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/30/2020] [Accepted: 11/16/2020] [Indexed: 02/08/2023] Open
Abstract
This paper aims to provide a comprehensive review of the changing role of hepatocyte growth factor (HGF) signaling in the healthy and diseased synovial joint and spine. HGF is a multifunctional growth factor that, like its specific receptor c-Met, is widely expressed in several bone and joint tissues. HGF has profound effects on cell survival and proliferation, matrix metabolism, inflammatory response, and neurotrophic action. HGF plays an important role in normal bone and cartilage turnover. Changes in HGF/c-Met have also been linked to pathophysiological changes in degenerative joint diseases, such as osteoarthritis (OA) and intervertebral disc degeneration (IDD). A therapeutic role of HGF has been proposed in the regeneration of osteoarticular tissues. HGF also influences bone remodeling and peripheral nerve activity. Studies aimed at elucidating the changing role of HGF/c-Met signaling in OA and IDD at different pathophysiological stages, and their specific molecular mechanisms are needed. Such studies will contribute to safe and effective HGF/c-Met signaling-based treatments for OA and IDD.
Collapse
|
3
|
Abed E, Bouvard B, Martineau X, Jouzeau JY, Reboul P, Lajeunesse D. Elevated hepatocyte growth factor levels in osteoarthritis osteoblasts contribute to their altered response to bone morphogenetic protein-2 and reduced mineralization capacity. Bone 2015; 75:111-9. [PMID: 25667190 DOI: 10.1016/j.bone.2015.02.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 01/24/2015] [Accepted: 02/01/2015] [Indexed: 10/24/2022]
Abstract
PURPOSE Clinical and in vitro studies suggest that subchondral bone sclerosis due to abnormal osteoblasts is involved in the progression of osteoarthritis (OA). Human osteoblasts isolated from sclerotic subchondral OA bone tissue show an altered phenotype, a decreased canonical Wnt/ß-catenin pathway, and a reduced mineralization in vitro as well as in vivo. These alterations were linked with an abnormal response to BMP-2. OA osteoblasts release factors such as the hepatocyte growth factor (HGF) that contribute to cartilage loss whereas chondrocytes do not express HGF. HGF can stimulate BMP-2 expression in human osteoblasts, however, the role of HGF and its effect in OA osteoblasts remains unknown. Here we investigated whether elevated endogenous HGF levels in OA osteoblasts are responsible for their altered response to BMP-2. METHODS We prepared primary human subchondral osteoblasts using the sclerotic medial portion of the tibial plateaus of OA patients undergoing total knee arthroplasty, or from tibial plateaus of normal individuals obtained at autopsy. The expression of HGF was evaluated by qRT-PCR and the protein production by western blot analysis. HGF expression was reduced with siRNA technique whereas its activity was inhibited using the selective inhibitor PHA665752. Alkaline phosphatase activity (ALPase) and osteocalcin release were measured by substrate hydrolysis and EIA respectively. Canonical Wnt/β-catenin signaling (cWnt) was evaluated both by target gene expression using the TOPflash TCF/lef luciferase reporter assay and western blot analysis of β-catenin levels in response to Wnt3a stimulation. Mineralization in response to BMP-2 was evaluated by alizarin red staining. RESULTS The expression of HGF was increased in OA osteoblasts compared to normal osteoblasts and was maintained during their in vitro differentiation. OA osteoblasts released more HGF than normal osteoblasts as assessed by western blot analysis. HGF stimulated the expression of TGF-β1. BMP-2 dose-dependently (1 to 100 ng/ml) stimulated both ALPase and osteocalcin in normal osteoblasts whereas, it inhibited them in OA osteoblasts. HGF-siRNA treatments reversed this response in OA osteoblasts and restored the BMP-2 response. cWnt is reduced in OA osteoblasts compared to normal, and HGF-siRNA treatments increased cWnt in OA osteoblasts almost to normal. Smad1/5/8 phosphorylation in response to BMP-2, which is reduced in OA osteoblasts, was corrected when these cells were treated with PHA665752. The BMP-2-dependent mineralization of OA osteoblasts, which is also reduced compared to normal, was only partially restored by PHA665752 treatment whereas 28 days treatment with HGF reduced the mineralization of normal osteoblasts. CONCLUSION OA osteoblasts expressed more HGF than normal osteoblasts. Increased endogenous HGF production in OA osteoblasts stimulated the expression of TGF-β1 and reduced their response to BMP-2. Inhibiting HGF expression or HGF signaling restored the response to BMP-2 and Smad1/5/8 signaling. In addition, decreased HGF signaling partly corrects the abnormal mineralization of OA osteoblasts while increased HGF prevents the normal mineralization of normal osteoblasts. In summary, we hypothesize that sustained elevated HGF levels in OA osteoblasts drive their abnormal phenotype and is implicated in OA pathophysiology.
Collapse
Affiliation(s)
- E Abed
- Unité de recherche en Arthrose, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - B Bouvard
- UMR7365 IMoPA, Université de Lorraine/CNRS, Vandœuvre lès Nancy, 54505, France; Service de Rhumatologie, Centre Hospitalier Universitaire (CHU), Angers 49933, France
| | - X Martineau
- Unité de recherche en Arthrose, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - J-Y Jouzeau
- UMR7365 IMoPA, Université de Lorraine/CNRS, Vandœuvre lès Nancy, 54505, France; Service de Pharmacologie Clinique et de Toxicologie, Centre Hospitalier Universitaire (CHU), Nancy 54023, France
| | - P Reboul
- UMR7365 IMoPA, Université de Lorraine/CNRS, Vandœuvre lès Nancy, 54505, France
| | - D Lajeunesse
- Unité de recherche en Arthrose, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada.
| |
Collapse
|
4
|
Shepard JB, Jeong JW, Maihle NJ, O'Brien S, Dealy CN. Transient anabolic effects accompany epidermal growth factor receptor signal activation in articular cartilage in vivo. Arthritis Res Ther 2014; 15:R60. [PMID: 23705804 PMCID: PMC4060279 DOI: 10.1186/ar4233] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 02/17/2013] [Accepted: 05/25/2013] [Indexed: 02/06/2023] Open
Abstract
Introduction Signals from the epidermal growth factor receptor (EGFR) have typically been considered to provide catabolic activities in articular cartilage, and accordingly have been suggested to have a causal role in osteoarthritis progression. The aim of this study was to determine in vivo roles for endogenous EGFR signal activation in articular cartilage. Methods Transgenic mice with conditional, limb-targeted deletion of the endogenous intracellular EGFR inhibitor Mig-6 were generated using CreLoxP (Mig-6-flox; Prx1Cre) recombination. Histology, histochemical staining and immunohistochemistry were used to confirm activation of EGFR signaling in the articular cartilage and joints, and to analyze phenotypic consequences of Mig-6 loss on articular cartilage morphology, proliferation, expression of progenitor cell markers, presence of chondrocyte hypertrophy and degradation of articular cartilage matrix. Results The articular cartilage of Mig-6-conditional knockout (Mig-6-cko) mice was dramatically and significantly thicker than normal articular cartilage at 6 and 12 weeks of age. Mig-6-cko articular cartilage contained a population of chondrocytes in which EGFR signaling was activated, and which were three to four times more proliferative than normal Mig-6-flox articular chondrocytes. These cells expressed high levels of the master chondrogenic regulatory factor Sox9, as well as high levels of putative progenitor cell markers including superficial zone protein (SZP), growth and differentiation factor-5 (GDF-5) and Notch1. Expression levels were also high for activated β-catenin and the transforming growth factor beta (TGF-β) mediators phospho-Smad2/3 (pSmad2/3). Anabolic effects of EGFR activation in articular cartilage were followed by catabolic events, including matrix degradation, as determined by accumulation of aggrecan cleavage fragments, and onset of hypertrophy as determined by type × collagen expression. By 16 weeks of age, the articular cartilage of Mig-6-cko knees was no longer thickened and was degenerating. Conclusions These results demonstrate unexpected anabolic effects of EGFR signal activation in articular cartilage, and suggest the hypothesis that these effects may promote the expansion and/or activity of an endogenous EGFR-responsive cell population within the articular cartilage.
Collapse
|
5
|
Maumus M, Manferdini C, Toupet K, Peyrafitte JA, Ferreira R, Facchini A, Gabusi E, Bourin P, Jorgensen C, Lisignoli G, Noël D. Adipose mesenchymal stem cells protect chondrocytes from degeneration associated with osteoarthritis. Stem Cell Res 2013; 11:834-44. [PMID: 23811540 DOI: 10.1016/j.scr.2013.05.008] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 04/05/2013] [Accepted: 05/19/2013] [Indexed: 12/18/2022] Open
Abstract
Our work aimed at evaluating the role of adipose stem cells (ASC) on chondrocytes from osteoarthritic (OA) patients and identifying the mediators involved. We used primary chondrocytes, ASCs from different sources and bone marrow mesenchymal stromal cells (MSC) from OA donors. ASCs or MSCs were co-cultured with chondrocytes in a minimal medium and using cell culture inserts. Under these conditions, ASCs did not affect the proliferation of chondrocytes but significantly decreased camptothecin-induced apoptosis. Both MSCs and ASCs from different sources allowed chondrocytes in the cocultures maintaining a stable expression of markers specific for a mature phenotype, while expression of hypertrophic and fibrotic markers was decreased. A number of factors known to regulate the chondrocyte phenotype (IL-1β, IL-1RA, TNF-α) and matrix remodeling (TIMP-1 and -2, MMP-1 and -9, TSP-1) were not affected. However, a significant decrease of TGF-β1 secretion by chondrocytes and induction of HGF secretion by ASCs was observed. Addition of a neutralizing anti-HGF antibody reversed the anti-fibrotic effect of ASCs whereas hypertrophic markers were not modulated. In summary, ASCs are an interesting source of stem cells for efficiently reducing hypertrophy and dedifferentiation of chondrocytes, at least partly via the secretion of HGF. This supports the interest of using these cells in therapies for osteo-articular diseases.
Collapse
Affiliation(s)
- Marie Maumus
- Inserm, U 844, Hôpital Saint-Eloi, Montpellier F-34295, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Tibesku CO, Daniilidis K, Szuwart T, Jahn UR, Schlegel PM, Fuchs-Winkelmann S. Influence of hepatocyte growth factor on autologous osteochondral transplants in an animal model. Arch Orthop Trauma Surg 2011; 131:1145-51. [PMID: 21359871 DOI: 10.1007/s00402-011-1281-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Indexed: 12/21/2022]
Abstract
PURPOSE Several studies have investigated the influence of different growth factors on hyaline cartilage regeneration. In a rabbit model, hepatocyte growth factor (HGF) was proven to increase the amount of hyaline-like chondrocytes in a mixed fibro-cartilaginous regenerate of small defects. The aim of the current study was to evaluate whether intra-articular administration of HGF influences the ingrowth of osteochondral grafts in a sheep model. TYPE OF STUDY Animal experiment. METHODS Both knee joints of eight sheep were opened surgically and osteochondral grafts were harvested and simultaneously transplanted to the opposite condyle of the same joint. The sheep were divided into two groups of four sheep, resulting in 16 grafts per group. In one group, HGF was administered by bilateral intra-articular injections given three times a week for 4 weeks. The control group received isotonic sodium chloride injections. The animals were killed after 3 months. RESULTS Histological evaluation showed a complete ingrowth of the osseous part of the osteochondral grafts. A healing or ingrowth at the level of the cartilage could not be observed. Histological evaluation of the transplanted grafts according to the modified Mankin score revealed less degeneration in the cartilage of the HGF group, as compared to the control group. In the HGF group, less cloning of chondrocytes and less irregularities of the articular surface were observed. Importantly, no deleterious effects, such as osteophyte formation, cartilage thickening or synovial proliferation, were found. CONCLUSION HGF positively influenced the cellularity of the transplanted osteochondral graft, but could not diminish the fissures in the marginal zone of the grafts. CLINICAL RELEVANCE Marginal zone fissures and degeneration in the absence of HGF may undermine long-term results of autologous osteochondral grafts.
Collapse
|
7
|
Giannoni P, Scaglione S, Quarto R, Narcisi R, Parodi M, Balleari E, Barbieri F, Pattarozzi A, Florio T, Ferrini S, Corte G, de Totero D. An interaction between hepatocyte growth factor and its receptor (c-MET) prolongs the survival of chronic lymphocytic leukemic cells through STAT3 phosphorylation: a potential role of mesenchymal cells in the disease. Haematologica 2011; 96:1015-23. [PMID: 21486864 DOI: 10.3324/haematol.2010.029736] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Chronic lymphocytic leukemia cells are characterized by an apparent longevity in vivo which is lost when they are cultured in vitro. Cellular interactions and factors provided by the microenvironment appear essential to cell survival and may protect leukemic cells from the cytotoxicity of conventional therapies. Understanding the cross-talk between leukemic cells and stroma is of interest for identifying signals supporting disease progression and for developing novel therapeutic strategies. DESIGN AND METHODS Different cell types, sharing a common mesenchymal origin and representative of various bone marrow components, were used to challenge the viability of leukemic cells in co-cultures and in contact-free culture systems. Using a bioinformatic approach we searched for genes shared by lineages prolonging leukemic cell survival and further analyzed their biological role in signal transduction experiments. RESULTS Human bone marrow stromal cells, fibroblasts, trabecular bone-derived cells and an osteoblast-like cell line strongly enhanced survival of leukemic cells, while endothelial cells and chondrocytes did not. Gene expression profile analysis indicated two soluble factors, hepatocyte growth factor and CXCL12, as potentially involved. We demonstrated that hepatocyte growth factor and CXCL12 are produced only by mesenchymal lineages that sustain the survival of leukemic cells. Indeed chronic lymphocytic leukemic cells express a functional hepatocyte growth factor receptor (c-MET) and hepatocyte growth factor enhanced the viability of these cells through STAT3 phosphorylation, which was blocked by a c-MET tyrosine kinase inhibitor. The role of hepatocyte growth factor was confirmed by its short interfering RNA-mediated knock-down in mesenchymal cells. CONCLUSIONS The finding that hepatocyte growth factor prolongs the survival of chronic lymphocytic leukemic cells is novel and we suggest that the interaction between hepatocyte growth factor-producing mesenchymal and neoplastic cells contributes to maintenance of the leukemic clone.
Collapse
Affiliation(s)
- Paolo Giannoni
- Stem Cell Laboratory, Advanced Biotechnology Center, 16132 Genova, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Grandaunet B, Syversen SW, Hoff M, Sundan A, Haugeberg G, van Der Heijde D, Kvien TK, Standal T. Association between high plasma levels of hepatocyte growth factor and progression of radiographic damage in the joints of patients with rheumatoid arthritis. ACTA ACUST UNITED AC 2011; 63:662-9. [DOI: 10.1002/art.30163] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
9
|
The immunolocalization and possible role of c-Met (MET, hepatic growth factor receptor) in the developing human fetal mandibular condyle. Acta Histochem 2010; 112:482-8. [PMID: 19539981 DOI: 10.1016/j.acthis.2009.05.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Revised: 04/16/2009] [Accepted: 05/01/2009] [Indexed: 01/29/2023]
Abstract
The c-Met system is involved in skeletogenesis and is expressed in the cartilage of growth plates. However, the localization and role of c-Met during endochondral ossification of developing mandibular condyles or during intramembranous ossification has not yet been elucidated. In this study, c-Met was examined immunohistochemically in the mandibles of human fetuses during weeks 9 and 16 of pregnancy. c-Met was immunolocalised in the whole area of the developing mandible, although to different extents. In the intramembranous bone, mesenchymal cells showed a weak immunopositivity. Osteoprogenitor cells demonstrated a moderate immunopositivity for c-Met, while osteoblasts and osteocytes showed a very strong immunolabelling of c-Met. In the developing mandibular condyles, c-Met immunopositivity increased gradually throughout the proliferative layer towards the pre-hypertrophic cell layer, whereas the cells of the hypertrophic layer were weakly immunopositive. These findings have demonstrated, for the first time, the prominent immunolocalization of c-Met in osteogenic and chondrogenic tissues of developing human mandibles, which indicates possible functions for this receptor during mandibular development.
Collapse
|
10
|
IGF-1 does not moderate the time-dependent transcriptional patterns of key homeostatic genes induced by sustained compression of bovine cartilage. Osteoarthritis Cartilage 2009; 17:944-52. [PMID: 19250984 PMCID: PMC2752631 DOI: 10.1016/j.joca.2009.02.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 02/03/2009] [Accepted: 02/09/2009] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine changes in chondrocyte transcription of a range of anabolic, catabolic and signaling genes following simultaneous treatment of cartilage with Insulin-like growth factor-1 (IGF-1) and ramp-and-hold mechanical compression, and compare with effects on biosynthesis. METHODS Explant disks of bovine calf cartilage were slowly compressed (unconfined) over 3-min to their 1mm cut-thickness (0%-compression) or to 50%-compression with or without 300 ng/ml IGF-1. Expression of 24 genes involved in cartilage homeostasis was measured using qPCR at 2, 8, 24, 32, 48 h after compression +/-IGF-1. Clustering analysis was used to identify groups of co-expressed genes to further elucidate mechanistic pathways. RESULTS IGF-1 alone stimulated gene expression of aggrecan and collagen II, but simultaneous 24h compression suppressed this effect. Compression alone up-regulated expression of matrix metalloproteinase (MMP)-3, MMP-13, a disintegrin and metalloproteinase with thrombospondin motif (ADAMTS)-5 and transforming growth factor (TGF)-beta, an effect not reversed by simultaneous IGF-1 treatment. Temporal changes in expression following IGF-1 treatment were generally slower than that following compression. Clustering analysis revealed five distinct groups within which the pairings, tissue inhibitor of metalloproteinase (TIMP)-3 and ADAMTS-5, MMP-1 and IGF-2, and IGF-1 and Collagen II, were all robustly co-expressed, suggesting inherent regulation and feedback in chondrocyte gene expression. While aggrecan synthesis was transcriptionally regulated by IGF-1, inhibition of aggrecan synthesis by sustained compression appeared post-transcriptionally regulated. CONCLUSION Sustained compression markedly altered the effects of IGF-1 on expression of genes involved in cartilage homeostasis, while IGF-1 was largely unable to moderate the transcriptional effects of compression alone. The demonstrated co-expressed gene pairings suggest a balance of anabolic and catabolic activity following simultaneous mechanical and growth factor stimuli.
Collapse
|
11
|
Abstract
Articular cartilage repair and regeneration continue to be largely intractable because of the poor regenerative properties of this tissue. The field of articular cartilage tissue engineering, which aims to repair, regenerate, and/or improve injured or diseased articular cartilage functionality, has evoked intense interest and holds great potential for improving articular cartilage therapy. This review provides an overall description of the current state of and progress in articular cartilage repair and regeneration. Traditional therapies and related problems are introduced. More importantly, a variety of promising cell sources, biocompatible tissue engineered scaffolds, scaffoldless techniques, growth factors, and mechanical stimuli used in current articular cartilage tissue engineering are reviewed. Finally, the technical and regulatory challenges of articular cartilage tissue engineering and possible future directions are also discussed.
Collapse
Affiliation(s)
- Lijie Zhang
- Department of Biomedical Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Jerry Hu
- Department of Biomedical Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Kyriacos A. Athanasiou
- Department of Biomedical Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA
| |
Collapse
|