1
|
Zhou P, Zhang J, Zhang M, Yang H, Liu Q, Zhang H, Liu J, Duan J, Lu Y, Wang M. Effects of occlusion modification on the remodelling of degenerative mandibular condylar processes. Oral Dis 2020; 26:597-608. [DOI: 10.1111/odi.13274] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 11/27/2019] [Accepted: 12/15/2019] [Indexed: 02/06/2023]
Affiliation(s)
- Ping Zhou
- Hunan Key Laboratory of Oral Health Research Hunan 3D Printing Engineering Research Center of Oral Care Hunan Clinical Research Center of Oral Major Diseases and Oral Health Xiangya Stomatological Hospital Xiangya School of Stomatology Central South University Changsha China
| | - Jing Zhang
- Department of Oral Anatomy and Physiology and Clinic of Temporomandibular Joint Disorders and Oral and Maxillofacial Pain The Key Laboratory of Military Stomatology of State the National Clinical Research Center for Oral Diseases School of Stomatology The Fourth Military Medical University Xi’an China
| | - Mian Zhang
- Department of Oral Anatomy and Physiology and Clinic of Temporomandibular Joint Disorders and Oral and Maxillofacial Pain The Key Laboratory of Military Stomatology of State the National Clinical Research Center for Oral Diseases School of Stomatology The Fourth Military Medical University Xi’an China
| | - Hongxu Yang
- Department of Oral Anatomy and Physiology and Clinic of Temporomandibular Joint Disorders and Oral and Maxillofacial Pain The Key Laboratory of Military Stomatology of State the National Clinical Research Center for Oral Diseases School of Stomatology The Fourth Military Medical University Xi’an China
| | - Qian Liu
- Department of Oral Anatomy and Physiology and Clinic of Temporomandibular Joint Disorders and Oral and Maxillofacial Pain The Key Laboratory of Military Stomatology of State the National Clinical Research Center for Oral Diseases School of Stomatology The Fourth Military Medical University Xi’an China
| | - Hongyun Zhang
- Department of Oral Anatomy and Physiology and Clinic of Temporomandibular Joint Disorders and Oral and Maxillofacial Pain The Key Laboratory of Military Stomatology of State the National Clinical Research Center for Oral Diseases School of Stomatology The Fourth Military Medical University Xi’an China
| | - Jinqiang Liu
- School of Stomatology Jiamusi University Jiamusi China
| | - Jing Duan
- Department of Oral Anatomy and Physiology and Clinic of Temporomandibular Joint Disorders and Oral and Maxillofacial Pain The Key Laboratory of Military Stomatology of State the National Clinical Research Center for Oral Diseases School of Stomatology The Fourth Military Medical University Xi’an China
| | - Yanqin Lu
- Hunan Key Laboratory of Oral Health Research Hunan 3D Printing Engineering Research Center of Oral Care Hunan Clinical Research Center of Oral Major Diseases and Oral Health Xiangya Stomatological Hospital Xiangya School of Stomatology Central South University Changsha China
| | - Mei‐Qing Wang
- Department of Oral Anatomy and Physiology and Clinic of Temporomandibular Joint Disorders and Oral and Maxillofacial Pain The Key Laboratory of Military Stomatology of State the National Clinical Research Center for Oral Diseases School of Stomatology The Fourth Military Medical University Xi’an China
| |
Collapse
|
2
|
Jin Y, Cong Q, Gvozdenovic-Jeremic J, Hu J, Zhang Y, Terkeltaub R, Yang Y. Enpp1 inhibits ectopic joint calcification and maintains articular chondrocytes by repressing hedgehog signaling. Development 2018; 145:dev.164830. [PMID: 30111653 DOI: 10.1242/dev.164830] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/12/2018] [Indexed: 01/15/2023]
Abstract
The differentiated phenotype of articular chondrocytes of synovial joints needs to be maintained throughout life. Disruption of the articular cartilage, frequently associated with chondrocyte hypertrophy and calcification, is a central feature in osteoarthritis (OA). However, the molecular mechanisms whereby phenotypes of articular chondrocytes are maintained and pathological calcification is inhibited remain poorly understood. Recently, the ecto-enzyme Enpp1, a suppressor of pathological calcification, was reported to be decreased in joint cartilage with OA in both human and mouse, and Enpp1 deficiency causes joint calcification. Here, we found that hedgehog (Hh) signaling activation contributes to ectopic joint calcification in the Enpp1-/- mice. In the Enpp1-/- joints, Hh signaling was upregulated. Further activation of Hh signaling by removing the patched 1 gene in the Enpp1-/- mice enhanced ectopic joint calcification, whereas removing Gli2 partially rescued the ectopic calcification phenotype. In addition, reduction of Gαs in the Enpp1-/- mice enhanced joint calcification, suggesting that Enpp1 inhibits Hh signaling and chondrocyte hypertrophy by activating Gαs-PKA signaling. Our findings provide new insights into the mechanisms underlying Enpp1 regulation of joint integrity.
Collapse
Affiliation(s)
- Yunyun Jin
- Department of Developmental Biology, Harvard School of Dental Medicine, Harvard Stem Cell Institute, Boston, MA 02115, USA.,Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Qian Cong
- Department of Developmental Biology, Harvard School of Dental Medicine, Harvard Stem Cell Institute, Boston, MA 02115, USA
| | | | - Jiajie Hu
- Department of Developmental Biology, Harvard School of Dental Medicine, Harvard Stem Cell Institute, Boston, MA 02115, USA
| | - Yiqun Zhang
- Department of Developmental Biology, Harvard School of Dental Medicine, Harvard Stem Cell Institute, Boston, MA 02115, USA
| | - Robert Terkeltaub
- Department of Medicine, Veterans Affairs Healthcare System, University of California San Diego, 111K, 3350 La Jolla Village Dr., San Diego, CA 92161, USA
| | - Yingzi Yang
- Department of Developmental Biology, Harvard School of Dental Medicine, Harvard Stem Cell Institute, Boston, MA 02115, USA
| |
Collapse
|
3
|
Depletion of Gangliosides Enhances Articular Cartilage Repair in Mice. Sci Rep 2017; 7:43729. [PMID: 28252046 PMCID: PMC5333092 DOI: 10.1038/srep43729] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 01/27/2017] [Indexed: 12/23/2022] Open
Abstract
Elucidation of the healing mechanisms in damaged tissues is a critical step for establishing breakthroughs in tissue engineering. Articular cartilage is clinically one of the most successful tissues to be repaired with regenerative medicine because of its homogeneous extracellular matrix and few cell types. However, we only poorly understand cartilage repair mechanisms, and hence, regenerated cartilage remains inferior to the native tissues. Here, we show that glycosylation is an important process for hypertrophic differentiation during articular cartilage repair. GM3, which is a precursor molecule for most gangliosides, was transiently expressed in surrounding damaged tissue, and depletion of GM3 synthase enhanced cartilage repair. Gangliosides also regulated chondrocyte hypertrophy via the Indian hedgehog pathway. These results identify a novel mechanism of cartilage healing through chondrocyte hypertrophy that is regulated by glycosylation. Manipulation of gangliosides and their synthases may have beneficial effects on articular cartilage repair.
Collapse
|
4
|
Haddock G, Cross AK, Plumb J, Surr J, Buttle DJ, Bunning RAD, Woodroofe MN. Expression of ADAMTS-1, -4, -5 and TIMP-3 in normal and multiple sclerosis CNS white matter. Mult Scler 2016; 12:386-96. [PMID: 16900752 DOI: 10.1191/135248506ms1300oa] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) -1, -4 and -5 proteases have been identified in the CNS at the mRNA level. These glutamyl endopeptidases, inhibited by tissue inhibitor of metalloproteinases (TIMP)-3, are key enzymes in the degradation of the aggregating chondroitin sulphate proteoglycans (CSPGs), and may therefore play a role in CNS extracellular matrix (ECM) changes in multiple sclerosis (MS). We have investigated ADAMTS and TIMP-3 expression in normal and MS CNS white matter by real-time RT-PCR, western blotting and immunohistochemistry. We report for the first time the presence of ADAMTS-1, -4 and -5 in normal and MS white matter. Levels of ADAMTS-1 and -5 mRNA were decreased in MS compared to normal tissue, with no significant change in ADAMTS-4 mRNA levels. Protein levels of ADAMTS-4 were significantly higher in MS tissue compared to normal tissue. Immunohistochemical studies demonstrated that ADAMTS-4 was associated predominantly with astrocytes with increased expression within MS lesions. TIMP-3 mRNA was significantly decreased in MS compared to controls. These studies suggest a role for ADAMTS-4 in the pathogenesis of MS. Further studies on the activity of ADAMTS-4 will enable a better understanding of its role in the turnover of the ECM of white matter in MS.
Collapse
Affiliation(s)
- G Haddock
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB, UK.
| | | | | | | | | | | | | |
Collapse
|
5
|
Zhang Q, Ji Q, Wang X, Kang L, Fu Y, Yin Y, Li Z, Liu Y, Xu X, Wang Y. SOX9 is a regulator of ADAMTSs-induced cartilage degeneration at the early stage of human osteoarthritis. Osteoarthritis Cartilage 2015; 23:2259-2268. [PMID: 26162802 DOI: 10.1016/j.joca.2015.06.014] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 06/20/2015] [Accepted: 06/29/2015] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To identify whether cartilage master regulator SRY-related protein 9 (SOX9) mediates A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) dysregulation during osteoarthritis (OA) cartilage degeneration. METHOD Twenty-two randomly selected OA patients were evaluated using Outerbridge Classification via arthroscopy. Haematoxylin-eosin (HE), Safranin O and Masson staining were performed for the histopathological assessment. The expression of ADAMTSs, collagen 2A1 (COL2A1), aggrecan (ACAN), cartilage oligomeric matrix protein (COMP) and SOX9 were examined using real-time quantitative Polymerase Chain Reaction (PCR) (RT-qPCR) and western blotting analysis. Immunohistochemistry (IHC) analysis was performed to investigate the production of ADAMTSs in cartilage tissues. The association between SOX9 production and ADAMTSs, COL2A1, ACAN, and COMP expression was established by full-depth cartilage biopsies. RESULTS ADAMTSs expression levels were repressed at stage 1, while a significant increase was observed at the progressive stage of OA. SOX9 was upregulated at stage 1 and suppressed at a later stage of cartilage development, particularly in cartilage with severe damage. In addition, SOX9 repressed the expression of ADAMTSs and promoted COL2A1, ACAN and COMP expression in human chondrocytes. SOX9 was recruited to the promoters of ADAMTS-4 and ADAMTS-7. SOX9 expression was negatively correlated with ADAMTSs production and was positively associated with COL2A1, ACAN and COMP expression. Inhibition of ADAMTSs markedly increased the production of COL2A1, ACAN and COMP in chondrocytes isolated from the early stage of OA. CONCLUSIONS These findings indicated that SOX9 upregulation might mediate ADAMTSs suppression at the early stage of human OA. In addition, SOX9 could be used as a potential therapeutic agent for human OA at an early stage.
Collapse
Affiliation(s)
- Q Zhang
- Department of Orthopaedics, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China; Department of Orthopaedic Surgery, Royal Liverpool University Hospital, Prescot Street, Liverpool, UK
| | - Q Ji
- Department of Orthopaedics, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - X Wang
- Department of Neurology, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - L Kang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, China
| | - Y Fu
- Department of Orthopaedics, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - Y Yin
- Department of Orthopaedics, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - Z Li
- Department of Orthopaedics, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - Y Liu
- Department of Orthopaedics, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - X Xu
- Beijing Institute of Biotechnology, Beijing 100850, China.
| | - Y Wang
- Department of Orthopaedics, The General Hospital of Chinese People's Liberation Army, Beijing 100853, China.
| |
Collapse
|
6
|
Green JD, Tollemar V, Dougherty M, Yan Z, Yin L, Ye J, Collier Z, Mohammed MK, Haydon RC, Luu HH, Kang R, Lee MJ, Ho SH, He TC, Shi LL, Athiviraham A. Multifaceted signaling regulators of chondrogenesis: Implications in cartilage regeneration and tissue engineering. Genes Dis 2015; 2:307-327. [PMID: 26835506 PMCID: PMC4730920 DOI: 10.1016/j.gendis.2015.09.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 09/16/2015] [Indexed: 01/08/2023] Open
Abstract
Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature. Current surgical treatment options do not ensure consistent regeneration of hyaline cartilage in favor of fibrous tissue. Here, we review the current understanding of the most important biological regulators of chondrogenesis and their interactions, to provide insight into potential applications for cartilage tissue engineering. These include various signaling pathways, including: fibroblast growth factors (FGFs), transforming growth factor β (TGF-β)/bone morphogenic proteins (BMPs), Wnt/β-catenin, Hedgehog, Notch, hypoxia, and angiogenic signaling pathways. Transcriptional and epigenetic regulation of chondrogenesis will also be discussed. Advances in our understanding of these signaling pathways have led to promising advances in cartilage regeneration and tissue engineering.
Collapse
Affiliation(s)
- Jordan D. Green
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Viktor Tollemar
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Mark Dougherty
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Zhengjian Yan
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Liangjun Yin
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Jixing Ye
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
- School of Bioengineering, Chongqing University, Chongqing, China
| | - Zachary Collier
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Maryam K. Mohammed
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Rex C. Haydon
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Hue H. Luu
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Richard Kang
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Michael J. Lee
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Sherwin H. Ho
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Tong-Chuan He
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Lewis L. Shi
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Aravind Athiviraham
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| |
Collapse
|
7
|
Winkler NS, Fautsch MP. Effects of prostaglandin analogues on aqueous humor outflow pathways. J Ocul Pharmacol Ther 2013; 30:102-9. [PMID: 24359106 DOI: 10.1089/jop.2013.0179] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Elevated intraocular pressure (IOP) is the most prevalent risk factor for glaucoma. All treatments, whether surgical or pharmaceutical, are aimed at lowering IOP. Prostaglandin analogues are a first line therapy for glaucoma due to their ability to reduce IOP, once-daily dosing, efficacy, and minimal side-effect profile. Whereas prostaglandin analogues have been known to alter aqueous humor outflow through the unconventional (uveoscleral) pathway, more recent evidence suggests their action also occurs through the conventional (trabecular) pathway. Understanding how prostaglandin analogues successfully lower IOP is important, as this information may lead to the discovery of new molecular targets for future therapeutic intervention. This review explores the current understanding of prostaglandin analogue biology as it pertains to IOP reduction and improved aqueous humor outflow facility.
Collapse
|
8
|
Atobe M, Maekawara N, Ishiguro N, Sogame S, Suenaga Y, Kawanishi M, Suzuki H, Jinno N, Tanaka E, Miyoshi S. A series of thiazole derivatives bearing thiazolidin-4-one as non-competitive ADAMTS-5 (aggrecanase-2) inhibitors. Bioorg Med Chem Lett 2013; 23:2106-10. [DOI: 10.1016/j.bmcl.2013.01.121] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 01/24/2013] [Accepted: 01/28/2013] [Indexed: 10/27/2022]
|
9
|
Ng VY, Jump SS, Santangelo KS, Russell DS, Bertone AL. Genetic engineering of juvenile human chondrocytes improves scaffold-free mosaic neocartilage grafts. Clin Orthop Relat Res 2013; 471:26-38. [PMID: 23008026 PMCID: PMC3528904 DOI: 10.1007/s11999-012-2615-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 09/12/2012] [Indexed: 01/31/2023]
Abstract
BACKGROUND Current cartilage transplantation techniques achieve suboptimal restoration and rely on patient donor cells or living grafts of chondrocytes. PURPOSE We sought to enhance allogeneic grafts by testing mosaics of genetically engineered and naïve juvenile human chondrocytes (jCh). METHODS We obtained specimens from three humans and performed three experiments (two in vitro, one in vivo). We compared neocartilage with and without (1) supplemented serum-free medium (chondrocyte differentiation medium [CDM]), (2) adenoviral BMP-2 (AdBMP-2) transduction, and (3) varying ratios (0.1-1) of transduced and naïve jCh. We compared (4) healing with mosaic grafts with naïve neocartilage or marrow stimulation in immunosuppressed rats. For each of 10 in vitro treatment groups, we had six replicates for each human, and for each of three in vivo treatment groups, we had four replicates for one human. We scored the histology with the semiquantitative Bern score. RESULTS AdBMP-2 and naïve neocartilage growth in CDM were histologically superior (Bern score, 5.2 versus 3.7; 8.0 versus 1.8) and size (8.0 versus 6.1; 7.9 versus 2.2 mg) to standard medium. In CDM, AdBMP-2 decreased viability (76% versus 90%), but increased BMP-2 production (619 ng/mL versus 43 pg/mL). Ten percent and 25% AdBMP-2 transduction had Bern scores of 6.8 and 6.5 and viability of 84% and 83%, respectively. Twenty-five percent mosaic grafts provided better healing histologically than marrow stimulation or naive neocartilage. CONCLUSIONS Low-level AdBMP-2 and CDM augment neocartilage parameters in vitro and vivo. CLINICAL RELEVANCE Genetic augmentation of jCh and creation of mosaic neocartilage may improve graft viability and articular healing compared with naïve neocartilage.
Collapse
Affiliation(s)
- Vincent Y. Ng
- />Department of Orthopaedics, The Ohio State University Wexner Medical Center, Columbus, OH USA
| | - Seth S. Jump
- />Sports Medicine Center, The Ohio State University Wexner Medical Center, Columbus, OH USA
- />Department of Veterinary Clinical Sciences, The Ohio State University Veterinary Medical Center, Columbus, OH USA
| | - Kelly S. Santangelo
- />Department of Veterinary Biosciences, The Ohio State University, Columbus, OH USA
| | - Duncan S. Russell
- />Department of Veterinary Biosciences, The Ohio State University, Columbus, OH USA
| | - Alicia L. Bertone
- />Department of Orthopaedics, The Ohio State University Wexner Medical Center, Columbus, OH USA
- />Sports Medicine Center, The Ohio State University Wexner Medical Center, Columbus, OH USA
- />Department of Veterinary Clinical Sciences, The Ohio State University Veterinary Medical Center, Columbus, OH USA
- />College of Veterinary Medicine, The Ohio State University, 601 Tharp Street, Columbus, OH 43210 USA
| |
Collapse
|
10
|
Seito N, Yamashita T, Tsukuda Y, Matsui Y, Urita A, Onodera T, Mizutani T, Haga H, Fujitani N, Shinohara Y, Minami A, Iwasaki N. Interruption of glycosphingolipid synthesis enhances osteoarthritis development in mice. ACTA ACUST UNITED AC 2012; 64:2579-88. [PMID: 22391889 DOI: 10.1002/art.34463] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Glycosphingolipids (GSLs) are ubiquitous membrane components that modulate transmembrane signaling and mediate cell-to-cell and cell-to-matrix interactions. GSL expression is decreased in the articular cartilage of humans with osteoarthritis (OA). This study was undertaken to determine the functional role of GSLs in cartilage metabolism related to OA pathogenesis in mice. METHODS We generated mice with knockout of the chondrocyte-specific Ugcg gene, which encodes an initial enzyme of major GSL synthesis, using the Cre/loxP system (Col2-Ugcg(-/-) mice). In vivo OA and in vitro cartilage degradation models were used to evaluate the effect of GSLs on the cartilage degradation process. RESULTS Although Col2-Ugcg(-/-) mice developed and grew normally, OA changes in these mice were dramatically enhanced with aging, through the overexpression of matrix metalloproteinase 13 and chondrocyte apoptosis, compared to their wild-type (WT) littermates. Col2-Ugcg(-/-) mice showed more severe instability-induced pathologic OA in vivo and interleukin-1α (IL-1α)-induced cartilage degradation in vitro. IL-1α stimulation of chondrocytes from WT mice significantly increased Ugcg messenger RNA expression and up-regulated GSL metabolism. CONCLUSION Our results indicate that GSL deficiency in mouse chondrocytes enhances the development of OA. However, this deficiency does not affect the development and organization of cartilage tissue in mice at a young age. These findings indicate that GSLs maintain cartilage molecular metabolism and prevent disease progression, although GSLs are not essential for chondrogenesis of progenitor and stem cells and cartilage development in young mice. GSL metabolism in the cartilage is a potential target for developing a novel treatment for OA.
Collapse
|
11
|
Kumar S, Rao N, Ge R. Emerging Roles of ADAMTSs in Angiogenesis and Cancer. Cancers (Basel) 2012; 4:1252-99. [PMID: 24213506 PMCID: PMC3712723 DOI: 10.3390/cancers4041252] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 11/21/2012] [Accepted: 11/23/2012] [Indexed: 12/18/2022] Open
Abstract
A Disintegrin-like And Metalloproteinase with ThromboSpondin motifs—ADAMTSs—are a multi-domain, secreted, extracellular zinc metalloproteinase family with 19 members in humans. These extracellular metalloproteinases are known to cleave a wide range of substrates in the extracellular matrix. They have been implicated in various physiological processes, such as extracellular matrix turnover, melanoblast development, interdigital web regression, blood coagulation, ovulation, etc. ADAMTSs are also critical in pathological processes such as arthritis, atherosclerosis, cancer, angiogenesis, wound healing, etc. In the past few years, there has been an explosion of reports concerning the role of ADAMTS family members in angiogenesis and cancer. To date, 10 out of the 19 members have been demonstrated to be involved in regulating angiogenesis and/or cancer. The mechanism involved in their regulation of angiogenesis or cancer differs among different members. Both angiogenesis-dependent and -independent regulation of cancer have been reported. This review summarizes our current understanding on the roles of ADAMTS in angiogenesis and cancer and highlights their implications in cancer therapeutic development.
Collapse
Affiliation(s)
- Saran Kumar
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
| | | | | |
Collapse
|
12
|
Modulating hedgehog signaling can attenuate the severity of osteoarthritis. Nat Med 2009; 15:1421-5. [PMID: 19915594 DOI: 10.1038/nm.2055] [Citation(s) in RCA: 250] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Accepted: 10/02/2009] [Indexed: 11/08/2022]
Abstract
Osteoarthritis is associated with the irreversible degeneration of articular cartilage. Notably, in this condition, articular cartilage chondrocytes undergo phenotypic and gene expression changes that are reminiscent of their end-stage differentiation in the growth plate during skeletal development. Hedgehog (Hh) signaling regulates normal chondrocyte growth and differentiation; however, the role of Hh signaling in chondrocytes in osteoarthritis is unknown. Here we examine human osteoarthritic samples and mice in which osteoarthritis was surgically induced and find that Hh signaling is activated in osteoarthritis. Using several genetically modified mice, we found that higher levels of Hh signaling in chondrocytes cause a more severe osteoarthritic phenotype. Furthermore, we show in mice and in human cartilage explants that pharmacological or genetic inhibition of Hh signaling reduces the severity of osteoarthritis and that runt-related transcription factor-2 (RUNX2) potentially mediates this process by regulating a disintegrin and metalloproteinase with thrombospondin type 1 motif-5 (ADAMTS5) expression. Together, these findings raise the possibility that Hh blockade can be used as a therapeutic approach to inhibit articular cartilage degeneration.
Collapse
|
13
|
Ding L, Guo D, Homandberg GA. The cartilage chondrolytic mechanism of fibronectin fragments involves MAP kinases: comparison of three fragments and native fibronectin. Osteoarthritis Cartilage 2008; 16:1253-62. [PMID: 18396067 DOI: 10.1016/j.joca.2008.02.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Accepted: 02/17/2008] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To define the role of mitogen activated protein (MAP) kinases in fibronectin fragment (Fn-f) mediated matrix metalloproteinase (MMP) upregulation and damage to bovine cartilage and to compare activities of three Fn-fs with native fibronectin (Fn), which is inactive in terms of cartilage damage. METHODS Bovine chondrocytes were cultured with three Fn-fs, an amino-terminal 29-kDa, a gelatin-binding 50-kDa and a central 140-kDa Fn-f or native Fn at concentrations from 0.01 to 1 microM, concentrations lower than those found in osteoarthritis synovial fluids. Lysates were probed for activation of MAP kinases, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 and stress activated protein kinase/c-jun N-terminal kinase (SAPK/JNK). Confocal fluorescent microscopy was used to visualize movement of activated kinases. Kinase inhibitors were tested for their abilities to block Fn-f mediated protein upregulation of MMP-3 and MMP-13 and Fn-f induced depletion of cartilage proteoglycan (PG) from cultured explants. RESULTS The 29-kDa, the most potent Fn-f in terms of cartilage damage, enhanced phosphorylation of ERK1/2, p38 and JNK1/2 within a 1-h incubation while the 50 and 140-kDa Fn-fs required up to 4 h for maximal activity and native Fn was only minimally active toward p38 and JNK, but did strongly activate ERK1/2. The activated kinases displayed a distribution toward the nuclear membrane and within the nucleus. MAP kinase inhibitors markedly decreased Fn-f mediated upregulation of MMP-3 or MMP-13 and Fn-f mediated cartilage PG depletion. CONCLUSIONS These results suggest that Fn-fs upregulate MMP-3 and MMP-13 in bovine chondrocytes through MAP kinases and that kinase inhibitors afford protection against this degenerative pathway.
Collapse
Affiliation(s)
- L Ding
- Department of Biochemistry and Molecular Biology, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58202, United States
| | | | | |
Collapse
|
14
|
Majumdar MK, Chockalingam PS, Bhat RA, Sheldon R, Keohan C, Blanchet T, Glasson S, Morris EA. Immortalized mouse articular cartilage cell lines retain chondrocyte phenotype and respond to both anabolic factor BMP-2 and pro-inflammatory factor IL-1. J Cell Physiol 2008; 215:68-76. [PMID: 17960567 DOI: 10.1002/jcp.21282] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Articular cartilage chondrocytes help in the maintenance of tissue homeostasis and function of the articular joint. Study of primary chondrocytes in culture provides information closely related to in vivo functions of these cells. Limitations in the primary culture of chondrocytes have lead to the development of cells lines that serve as good surrogate models for the study of chondrocyte biology. In this study, we report the establishment and characterization of chondrocyte cell lines, MM-Sv/HP and MM-Sv/HP-2 from mouse articular cartilage. Cells were isolated from mouse femoral head articular cartilage, immortalized and maintained in culture through numerous passages. The morphology of the cells was from fibroblastic to polygonal in nature. Gene expression studies using quantitative PCR (Q-PCR) were performed on cells in monolayer culture and cells embedded in a three-dimensional alginate matrix. Stimulation of cells in monolayer culture with anabolic factor, BMP-2, resulted in increased gene expression of the extracellular matrix molecules, aggrecan and type II collagen and their regulator transcription factor, Sox9. Treatment by pro-inflammatory IL-1 resulted in increased gene expression of catabolic effectors including Aggrecanases (ADAMTS4, ADAMTS5), MMP-13 and nitric oxide synthase (Nos2). Cells in alginate treated with BMP-2 resulted in increased synthesis of proteoglycan which was released into the conditioned media on IL-1 stimulation. Western analysis of conditioned media showed the presence of Aggrecanase-cleaved aggrecan fragments. In summary, MM-Sv/HP and MM-Sv/HP-2 show preservation of important characteristics of articular chondrocytes as examined under multiple culture conditions and would provide a useful reagent in the study of chondrocyte biology.
Collapse
Affiliation(s)
- Manas K Majumdar
- Women's Health and Musculoskeletal Biology, Wyeth Research, Cambridge, Massachusetts, USA.
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Majumdar MK, Askew R, Schelling S, Stedman N, Blanchet T, Hopkins B, Morris EA, Glasson SS. Double-knockout of ADAMTS-4 and ADAMTS-5 in mice results in physiologically normal animals and prevents the progression of osteoarthritis. ACTA ACUST UNITED AC 2007; 56:3670-4. [PMID: 17968948 DOI: 10.1002/art.23027] [Citation(s) in RCA: 172] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To phenotypically characterize ADAMTS-4- and ADAMTS-5-double-knockout mice, and to determine the effect of deletion of ADAMTS-4 and ADAMTS-5 on the progression of osteoarthritis (OA) in mice. METHODS Mice lacking the catalytic domain of ADAMTS-4 and ADAMTS-5 were crossed to generate ADAMTS-4/5-double-knockout animals. Twelve-week-old and 1-year-old male and female ADAMTS-4/5-double-knockout mice were compared with age- and sex-matched wild-type (WT) mice by evaluating terminal body weights, organ weights, clinical pathology parameters, PIXImus mouse densitometry findings, and macroscopic and microscopic observations. ADAMTS-4/5-double-knockout mice were challenged by surgical induction of joint instability to determine the importance of these genes in the progression of OA. Articular and nonarticular cartilage explants from WT and ADAMTS-4/5-double-knockout mice were treated with interleukin-1 (IL-1) plus retinoic acid ex vivo, to examine proteoglycan degradation. RESULTS There were no genotype-related phenotype differences between ADAMTS-4/5-double-knockout and WT mice through 1 year of age, with the exception that female ADAMTS-4/5-double-knockout mice had a lower mean terminal body weight at the 12-week time point. Eight weeks after surgical induction of joint instability, OA was significantly less severe in ADAMTS-4/5-double-knockout mice compared with WT mice. Following stimulation of cartilage explants with IL-1 plus retinoic acid, aggrecanase-mediated degradation in ADAMTS-4/5-double-knockout mice was ablated, to a level comparable with that in ADAMTS-5-knockout mice. CONCLUSION Dual deletion of ADAMTS-4 and ADAMTS-5 generated mice that were phenotypically indistinguishable from WT mice. Deletion of ADAMTS-4/5 provided significant protection against proteoglycan degradation ex vivo and decreased the severity of murine OA. These effects in the ADAMTS-4/5-double-knockout mice were comparable with those observed with deletion of ADAMTS-5 alone.
Collapse
|
16
|
Oberholzer A, John T, Kohl B, Gust T, Müller RD, La Face D, Hutchins B, Zreiqat H, Ertel W, Schulze-Tanzil G. Adenoviral transduction is more efficient in alginate-derived chondrocytes than in monolayer chondrocytes. Cell Tissue Res 2007; 328:383-90. [PMID: 17265065 DOI: 10.1007/s00441-006-0371-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2006] [Accepted: 12/18/2006] [Indexed: 10/23/2022]
Abstract
Gene transfer into cultured chondrocytes by using adenoviral vectors has potential applications in treating cartilage disorders. The present study was undertaken to compare and optimize two chondrocyte culture conditions for adenoviral transduction efficacy by using primary human articular chondrocytes cultivated either directly in a monolayer condition or as outgrowths from alginate-stored chondrocyte cultures. Isolated primary chondrocytes from human articular cartilage were either immediately transduced with an EGFP (enhanced green fluorescent protein)-gene-bearing adenoviral vector (1,000 and 3,000 virus particles/cell) or cultured in alginate before transduction. Immunohistochemistry and flow cytometric analysis were employed to determine the expression of extracellular matrix proteins and of the alphavbeta5 integrin receptor involved in adenoviral cell entry. Monolayer chondrocytes exhibited moderate transduction rates (mean 22.2% and 46.9% EGFP-positive cells at 1,000 and 3,000 virus particles/cell by 72 h post-transduction), whereas alginate-derived chondrocytes revealed significantly higher transduction efficacies (95.7% and 99%). Both monolayer and alginate-derived chondrocytes expressed alphavbeta5 integrin, type II collagen and cartilage proteoglycans. The mean fluorescence intensity of type II collagen was significantly higher in the alginate-derived chondrocytes, whereas that of alphavbeta5 integrin was higher in the monolayer chondrocytes. Our results indicate that transduction efficacy is independent of alphavbeta5 integrin expression levels in chondrocytes. Moreover, adenoviral transduction of alginate-derived chondrocytes is more efficient than that for monolayer chondrocytes and may be a suitable tool to achieve sufficient numbers of transduced and differentiated chondrocytes for experimental applications and cartilage repair.
Collapse
Affiliation(s)
- A Oberholzer
- Department of Trauma and Reconstructive Surgery, Charité Medical Schools Berlin, Campus Benjamin Franklin, FEM, Krahmerstrasse 6-10, Berlin, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
LaVallie ER, Chockalingam PS, Collins-Racie LA, Freeman BA, Keohan CC, Leitges M, Dorner AJ, Morris EA, Majumdar MK, Arai M. Protein kinase Czeta is up-regulated in osteoarthritic cartilage and is required for activation of NF-kappaB by tumor necrosis factor and interleukin-1 in articular chondrocytes. J Biol Chem 2006; 281:24124-37. [PMID: 16798739 DOI: 10.1074/jbc.m601905200] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein kinase Czeta (PKCzeta) is an intracellular serine/threonine protein kinase that has been implicated in the signaling pathways for certain inflammatory cytokines, including interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF-alpha), in some cell types. A study of gene expression in articular chondrocytes from osteoarthritis (OA) patients revealed that PKCzeta is transcriptionally up-regulated in human OA articular cartilage clinical samples. This finding led to the hypothesis that PKCzeta may be an important signaling component of cytokine-mediated cartilage matrix destruction in articular chondrocytes, believed to be an underlying factor in the pathophysiology of OA. IL-1 treatment of chondrocytes in culture resulted in rapidly increased phosphorylation of PKCzeta, implicating PKCzeta activation in the signaling pathway. Chondrocyte cell-based assays were used to evaluate the contribution of PKCzeta activity in NF-kappaB activation and extracellular matrix degradation mediated by IL-1, TNF, or sphingomyelinase. In primary chondrocytes, IL-1 and TNF-alpha caused an increase in NF-kappaB activity resulting in induction of aggrecanase-1 and aggrecanase-2 expression, with consequent increased proteoglycan degradation. This effect was blocked by the pan-specific PKC inhibitors RO 31-8220 and bisindolylmaleimide I, partially blocked by Gö 6976, and was unaffected by the PKCzeta-sparing inhibitor calphostin C. A cell-permeable PKCzeta pseudosubstrate peptide inhibitor was capable of blocking TNFand IL-1-mediated NF-kappaB activation and proteoglycan degradation in chondrocyte pellet cultures. In addition, overexpression of a dominant negative PKCzeta protein effectively prevented cytokine-mediated NF-kappaB activation in primary chondrocytes. These data implicate PKCzeta as a necessary component of the IL-1 and TNF signaling pathways in chondrocytes that result in catabolic destruction of extracellular matrix proteins in osteoarthritic cartilage.
Collapse
Affiliation(s)
- Edward R LaVallie
- Departments of Biological Technologies and Women's Health and Musculoskeletal Biology, Wyeth Research, Cambridge, Massachusetts 02140-2325, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Flory JJE, Fosang AJ, Knudson W. The accumulation of intracellular ITEGE and DIPEN neoepitopes in bovine articular chondrocytes is mediated by CD44 internalization of hyaluronan. ACTA ACUST UNITED AC 2006; 54:443-54. [PMID: 16447219 PMCID: PMC3037829 DOI: 10.1002/art.21623] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE A dramatic loss of aggrecan proteoglycan from cartilage is associated with osteoarthritis. The fate of residual G1 domains of aggrecan is unknown, but inefficient turnover of these domains may impede subsequent repair and retention of newly synthesized aggrecan. Thus, the objective of this study was to determine whether ITEGE- and DIPEN-containing G1 domains, generated in situ, are internalized by articular chondrocytes, and whether these events are dependent on hyaluronan (HA) and its receptor, CD44. METHODS ITEGE and DIPEN neoepitopes were detected by immunofluorescence staining of bovine articular cartilage chondrocytes treated with or without interleukin-1alpha (IL-1alpha). Additionally, purified ITEGE- or DIPEN-containing G1 domains were aggregated with HA and then added to articular chondrocytes, articular chondrocytes transfected with CD44delta67, or COS-7 cells transfected with or without full-length CD44. Internalized epitopes were distinguished by their resistance to extensive trypsinization of the cell surface. RESULTS Both ITEGE and DIPEN were visualized within the extracellular cell-associated matrix of chondrocytes as well as within intracellular vesicles. Following trypsinization, the intracellular accumulation of both epitopes was clearly visible. IL-1 treatment increased extracellular as well as intracellular ITEGE epitope accumulation. Once internalized, the ITEGE neoepitope became localized within the nucleus and displayed little colocalization with HA, DIPEN, or other G1 domain epitopes. The internalization of both ITEGE and DIPEN G1 domains was dependent on the presence of HA and CD44. CONCLUSION One important mechanism for the elimination of residual G1 domains following extracellular degradation of aggrecan is CD44-mediated co-internalization with HA.
Collapse
Affiliation(s)
- Jennifer J. Embry Flory
- Jennifer J. Embry Flory, PhD, Warren Knudson, PhD: Rush Medical College, Rush University Medical Center, Chicago, Illinois
| | - Amanda J. Fosang
- Amanda J. Fosang, PhD: Arthritis Research Group, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Warren Knudson
- Jennifer J. Embry Flory, PhD, Warren Knudson, PhD: Rush Medical College, Rush University Medical Center, Chicago, Illinois
| |
Collapse
|
19
|
Majumdar MK, Chockalingam PS, Bhat RA, Sheldon R, Keohan C, Blanchet T, Glasson S, Morris EA. Immortalized cell lines from mouse xiphisternum preserve chondrocyte phenotype. J Cell Physiol 2006; 209:551-9. [PMID: 16883582 DOI: 10.1002/jcp.20775] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Chondrocytes are unique to cartilage and the study of these cells in vitro is important for advancing our understanding of the role of these cells in normal homeostasis and disease including osteoarthritis (OA). As there are limitations to the culture of primary chondrocytes, cell lines have been developed to overcome some of these obstacles. In this study, we developed a procedure to immortalize and characterize chondrocyte cell lines from mouse xiphisternum. The cells displayed a polygonal to fibroblastic morphology in monolayer culture. Gene expression studies using quantitative PCR showed that the cell lines responded to bone morphogenetic protein 2 (BMP-2) by increased expression of matrix molecules, aggrecan, and type II collagen together with transcriptional factor, Sox9. Stimulation by IL-1 results in the increased expression of catabolic effectors including MMP-13, nitric oxide synthase, ADAMTS4, and ADAMTS5. Cells cultured in alginate responded to BMP-2 by increased synthesis of proteoglycan (PG), a major matrix molecule of cartilage. IL-1 treatment of cells in alginate results in increased release of PG into the conditioned media. Further analysis of the media showed the presence of Aggrecanase-cleaved aggrecan fragments, a signature of matrix degradation. These results show that the xiphisternum chondrocyte cell lines preserve their chondrocyte phenotype cultured in either monolayer or 3-dimensional alginate bead culture systems. In summary, this study describes the establishment of chondrocyte cell lines from the mouse xiphisternum that may be useful as a surrogate model system to understand chondrocyte biology and to shed light on the underlying mechanism of pathogenesis in OA.
Collapse
Affiliation(s)
- Manas K Majumdar
- Wyeth Research, Department of Women's Health and Musculoskeletal Biology, Cambridge, Massachusetts 02140, USA.
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Abstract
PURPOSE OF REVIEW The prevalent nature of osteoarthritis, a cartilage degenerative disease that results in the erosion of joint surfaces and loss of mobility, underscores the importance of developing functional articular cartilage replacement. Recent research efforts have focused on tissue engineering as a promising approach for cartilage regeneration and repair. Tissue engineering is a multidisciplinary research area that incorporates both biological and engineering principles for the purpose of generating new, living tissues to replace the diseased/damaged tissue and restore tissue/organ function. This review surveys and highlights the current concepts and recent progress in cartilage tissue engineering, and discusses the challenges and potential of this rapidly advancing field of biomedical research. RECENT FINDINGS Cartilage tissue engineering is critically dependent on selection of appropriate cells (differentiated or progenitor cells); fabrication and utilization of biocompatible and mechanically suitable scaffolds for cell delivery; stimulation with chondrogenically bioactive molecules introduced in the form of recombinant proteins or via gene transfer; and application of dynamic, mechanical loading regimens for conditioning of the engineered tissue constructs, including the design of specialized biomechanically active bioreactors. SUMMARY Cell selection, scaffold design and biological stimulation remain the challenges of function tissue engineering. Successful regeneration or replacement of damaged or diseased cartilage will depend on future advances in our understanding of the biology of cartilage and stem cells and technological development in engineering.
Collapse
Affiliation(s)
- Catherine K Kuo
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland 20892-8022, USA
| | | | | | | |
Collapse
|