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Pinto-Cardoso R, Bessa-Andrês C, Correia-de-Sá P, Bernardo Noronha-Matos J. Could hypoxia rehabilitate the osteochondral diseased interface? Lessons from the interplay of hypoxia and purinergic signals elsewhere. Biochem Pharmacol 2023:115646. [PMID: 37321413 DOI: 10.1016/j.bcp.2023.115646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/03/2023] [Accepted: 06/07/2023] [Indexed: 06/17/2023]
Abstract
The osteochondral unit comprises the articular cartilage (90%), subchondral bone (5%) and calcified cartilage (5%). All cells present at the osteochondral unit that is ultimately responsible for matrix production and osteochondral homeostasis, such as chondrocytes, osteoblasts, osteoclasts and osteocytes, can release adenine and/or uracil nucleotides to the local microenvironment. Nucleotides are released by these cells either constitutively or upon plasma membrane damage, mechanical stress or hypoxia conditions. Once in the extracellular space, endogenously released nucleotides can activate membrane-bound purinoceptors. Activation of these receptors is fine-tuning regulated by nucleotides' breakdown by enzymes of the ecto-nucleotidase cascade. Depending on the pathophysiological conditions, both the avascular cartilage and the subchondral bone subsist to significant changes in oxygen tension, which has a tremendous impact on tissue homeostasis. Cell stress due to hypoxic conditions directly influences the expression and activity of several purinergic signalling players, namely nucleotide release channels (e.g. Cx43), NTPDase enzymes and purinoceptors. This review gathers experimental evidence concerning the interplay between hypoxia and the purinergic signalling cascade contributing to osteochondral unit homeostasis. Reporting deviations to this relationship resulting from pathological alterations of articular joints may ultimately unravel novel therapeutic targets for osteochondral rehabilitation. At this point, one can only hypothesize how hypoxia mimetic conditions can be beneficial to the ex vivo expansion and differentiation of osteo- and chondro-progenitors for auto-transplantation and tissue regenerative purposes.
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Affiliation(s)
- Rui Pinto-Cardoso
- Laboratório de Farmacologia e Neurobiologia; Center for Drug Discovery and Innovative Medicines (MedInUP), Departamento de Imuno-Fisiologia e Farmacologia, Instituto de Ciências Biomédicas Abel Salazar - Universidade do Porto (ICBAS-UP)
| | - Catarina Bessa-Andrês
- Laboratório de Farmacologia e Neurobiologia; Center for Drug Discovery and Innovative Medicines (MedInUP), Departamento de Imuno-Fisiologia e Farmacologia, Instituto de Ciências Biomédicas Abel Salazar - Universidade do Porto (ICBAS-UP)
| | - Paulo Correia-de-Sá
- Laboratório de Farmacologia e Neurobiologia; Center for Drug Discovery and Innovative Medicines (MedInUP), Departamento de Imuno-Fisiologia e Farmacologia, Instituto de Ciências Biomédicas Abel Salazar - Universidade do Porto (ICBAS-UP)
| | - José Bernardo Noronha-Matos
- Laboratório de Farmacologia e Neurobiologia; Center for Drug Discovery and Innovative Medicines (MedInUP), Departamento de Imuno-Fisiologia e Farmacologia, Instituto de Ciências Biomédicas Abel Salazar - Universidade do Porto (ICBAS-UP).
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Abstract
Cartilage resides under a low oxygen tension within articulating joints. The oxygen tension within cartilage of the knee joint has been measured to be between 2% and 5% oxygen. Although the literature has historically termed this level of oxygen as hypoxia, particularly when doing experiments in vitro in this range, this is actually the physiological oxygen tension experienced in vivo and is more accurately termed physioxia. In general, culture of chondrogenic cells under physioxia has demonstrated a donor-dependent beneficial effect on chondrogenesis, with an upregulation in cartilage genes (SOX9, COL2A1, ACAN) and matrix deposition (sulfated glycosaminoglycans (sGAGs), collagen II). Physioxia also reduces the expression of hypertrophic markers (COL10A1, MMP13). This chapter will outline the methods for the expansion and differentiation of chondrogenic cells under physioxia using oxygen-controlled incubators and glove box environments, with the typical assays used for qualitative and quantitative assessment of chondrogenesis.
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Affiliation(s)
- Girish Pattappa
- Experimental Trauma Surgery, Department of Trauma Surgery, University Medical Center of Regensburg, Regensburg, Germany
| | - Brandon D Markway
- Department of Orthopaedics & Rehabilitation, Oregon Health & Science University, Portland, OR, USA
| | - Denitsa Docheva
- Experimental Trauma Surgery, Department of Trauma Surgery, University Medical Center of Regensburg, Regensburg, Germany
- Department of Musculoskeletal Tissue Regeneration, Orthopaedic Hospital König-Ludwig-Haus, University of Wurzburg, Wurzburg, Germany
| | - Brian Johnstone
- Department of Orthopaedics & Rehabilitation, Oregon Health & Science University, Portland, OR, USA.
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Liau LL, Hassan MNFB, Tang YL, Ng MH, Law JX. Feasibility of Human Platelet Lysate as an Alternative to Foetal Bovine Serum for In Vitro Expansion of Chondrocytes. Int J Mol Sci 2021; 22:ijms22031269. [PMID: 33525349 PMCID: PMC7865277 DOI: 10.3390/ijms22031269] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/19/2021] [Accepted: 01/22/2021] [Indexed: 01/22/2023] Open
Abstract
Osteoarthritis (OA) is a degenerative joint disease that affects a lot of people worldwide. Current treatment for OA mainly focuses on halting or slowing down the disease progress and to improve the patient’s quality of life and functionality. Autologous chondrocyte implantation (ACI) is a new treatment modality with the potential to promote regeneration of worn cartilage. Traditionally, foetal bovine serum (FBS) is used to expand the chondrocytes. However, the use of FBS is not ideal for the expansion of cells mean for clinical applications as it possesses the risk of animal pathogen transmission and animal protein transfer to host. Human platelet lysate (HPL) appears to be a suitable alternative to FBS as it is rich in biological factors that enhance cell proliferation. Thus far, HPL has been found to be superior in promoting chondrocyte proliferation compared to FBS. However, both HPL and FBS cannot prevent chondrocyte dedifferentiation. Discrepant results have been reported for the maintenance of chondrocyte redifferentiation potential by HPL. These differences are likely due to the diversity in the HPL preparation methods. In the future, more studies on HPL need to be performed to develop a standardized technique which is capable of producing HPL that can maintain the chondrocyte redifferentiation potential reproducibly. This review discusses the in vitro expansion of chondrocytes with FBS and HPL, focusing on its capability to promote the proliferation and maintain the chondrogenic characteristics of chondrocytes.
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Affiliation(s)
- Ling Ling Liau
- Physiology Department, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Kuala Lumpur 56000, Malaysia;
| | - Muhammad Najib Fathi bin Hassan
- Centre for Tissue Engineering and Regenerative Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Kuala Lumpur 56000, Malaysia; (M.N.F.b.H.); (M.H.N.)
| | - Yee Loong Tang
- Pathology Department, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Kuala Lumpur 56000, Malaysia;
| | - Min Hwei Ng
- Centre for Tissue Engineering and Regenerative Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Kuala Lumpur 56000, Malaysia; (M.N.F.b.H.); (M.H.N.)
| | - Jia Xian Law
- Centre for Tissue Engineering and Regenerative Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Kuala Lumpur 56000, Malaysia; (M.N.F.b.H.); (M.H.N.)
- Correspondence: ; Tel.: +603-9145-7677; Fax: +603-9145-7678
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4
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Lehoczky G, Wolf F, Mumme M, Gehmert S, Miot S, Haug M, Jakob M, Martin I, Barbero A. Intra-individual comparison of human nasal chondrocytes and debrided knee chondrocytes: Relevance for engineering autologous cartilage grafts. Clin Hemorheol Microcirc 2020; 74:67-78. [PMID: 31743993 DOI: 10.3233/ch-199236] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Implantation of autologous chondrocytes for cartilage repair requires harvesting of undamaged cartilage, implying an additional joint arthroscopy surgery and further damage to the articular surface. As alternative possible cell sources, in this study we assessed the proliferation and chondrogenic capacity of debrided Knee Chondrocytes (dKC) and Nasal Chondrocytes (NC) collected from the same patients. METHODS Matched NC and dKC pairs from 13 patients enrolled in two clinical studies (NCT01605201 and NCT026739059) were expanded in monolayer and then chondro-differentiated in 3D collagenous scaffolds in medium with or without Transforming Growth Factor beta 1 (TGFβ1). Cell proliferation and amount of cartilage matrix production by these two cell types were assessed. RESULTS dKC exhibited an inferior proliferation rate than NC, and a lower capacity to chondro-differentiate. Resulting dKC-grafts contained lower amounts of cartilage specific matrix components glycosaminoglycans and type II collagen. The cartilage forming capacity of dKC did not significantly correlate with specific clinical parameters and was only partially improved by medium supplemention with TGFβ1. CONCLUSIONS dKC exhibit a reproducibly poor capacity to engineer cartilage grafts. Our in vitro data suggest that NC would be a better suitable cell source for the generation of autologous cartilage grafts.
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Affiliation(s)
- Gyözö Lehoczky
- Department of Surgery, University Hospital of Basel, Basel, Switzerland.,Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Francine Wolf
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Marcus Mumme
- Department of Surgery, University Hospital of Basel, Basel, Switzerland.,Department of Orthopaedics, University Children's Hospital Basel, Basel, Switzerland
| | - Sebastian Gehmert
- Department of Orthopaedics, University Children's Hospital Basel, Basel, Switzerland
| | - Sylvie Miot
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Martin Haug
- Department of Surgery, University Hospital of Basel, Basel, Switzerland
| | - Marcel Jakob
- Department of Surgery, University Hospital of Basel, Basel, Switzerland
| | - Ivan Martin
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Andrea Barbero
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
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Huang X, Zhong L, Hendriks J, Post JN, Karperien M. Different response of human chondrocytes from healthy looking areas and damaged regions to IL1β stimulation under different oxygen tension. J Orthop Res 2019; 37:84-93. [PMID: 30255592 DOI: 10.1002/jor.24142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 08/25/2018] [Indexed: 02/04/2023]
Abstract
Due to its avascular nature, articular cartilage is relatively hypoxic. The aim of this study was to elucidate the functional changes of macroscopically healthy looking areas chondrocytes (MHC) and macroscopically damaged regions chondrocytes (MDC) at a cellular level in response to the inflammatory cytokine IL1β under different oxygen tension levels. In this study, two-dimensional (2-D) expanded MHC and MDC were redifferentiated in 3-D pellet cultures in chondrogenic differentiation medium, supplemented with or without IL1β at conventional culture (normoxia) or 2.5% O2 (hypoxia) for 3 weeks. qPCR, immunohistochemistry and ELISA were used to detect the expression of anabolic and catabolic gene expression. Alcian blue/Safranin O staining and GAG assay were used to measure cartilage matrix production. Cell proliferation and apoptosis were assessed by EdU staining and TUNEL assay, respectively. The results showed that hypoxia enhanced matrix production in both MHC and MDC and this effect was stronger on MDC. Under normoxia, MHC showed higher expression of cartilage markers and lower catabolic genes expression than MDC. Interestingly, hypoxia diminished the difference between MHC and MDC. IL1β potently induced MMPs expression regardless of cell population and oxygen tension. The fold induction of these MMPs in hypoxia was however much higher than in normoxia. In addition, hypoxia promoted the expression of HIF1α and HIF2α in MHC, while it only enhanced HIF1α expression but decreased the HIF2α expression in MDC. We concluded that hypoxia stimulated the redifferentiation of cultured chondrocytes, particularly in MDC derived from macroscopically diseased cartilage. Oxygen tension may profoundly and differentially influence inflammation-associated cartilage injury and diseases by regulating the expression of HIF1α and HIF2α. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 9999:XX-XX, 2018.
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Affiliation(s)
- Xiaobin Huang
- Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, 7500 AE, The Netherlands
| | - Leilei Zhong
- Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, 7500 AE, The Netherlands
| | - Jan Hendriks
- Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, 7500 AE, The Netherlands
| | - Janine N Post
- Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, 7500 AE, The Netherlands
| | - Marcel Karperien
- Developmental BioEngineering, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, 7500 AE, The Netherlands
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Wu Y, Hospodiuk M, Peng W, Gudapati H, Neuberger T, Koduru S, Ravnic DJ, Ozbolat IT. Porous tissue strands: avascular building blocks for scalable tissue fabrication. Biofabrication 2018; 11:015009. [PMID: 30468153 DOI: 10.1088/1758-5090/aaec22] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The scalability of cell aggregates such as spheroids, strands, and rings has been restricted by diffusion of nutrient and oxygen into their core. In this study, we introduce a novel concept in generating tissue building blocks with micropores, which represents an alternative solution for vascularization. Sodium alginate porogens were mixed with human adipose-derived stem cells, and loaded into tubular alginate capsules, followed by de-crosslinking of the capsules. The resultant cellular structure exhibited a porous morphology and formed cell aggregates in the form of strands, called 'porous tissue strands (pTSs).' Three-dimensional reconstructions show that pTSs were able to maintain ∼25% porosity with a high pore interconnectivity (∼85%) for 3 weeks. Owing to the porous structure, pTSs showed up-regulated cell viability and proliferation rate as compared to solid counterparts throughout the culture period. pTSs also demonstrated self-assembly capability through tissue fusion yielding larger-scale patches. In this paper, chondrogenesis and osteogenesis of pTSs were also demonstrated, where the porous microstructure up-regulated both chondrogenic and osteogenic functionalities indicated by cartilage- and bone-specific immunostaining, quantitative biochemical assessment and gene expression. These findings indicated the functionality of pTSs, which possessed controllable porosity and self-assembly capability, and had great potential to be utilized as tissue building blocks in distinct applications such as cartilage and bone regeneration.
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Affiliation(s)
- Yang Wu
- Engineering Science and Mechanics Department, The Pennsylvania State University, State College, PA, United States of America. The Huck Institutes of the Life Sciences, The Pennsylvania State University, State College, PA, United States of America
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7
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Bergholt NL, Foss M, Saeed A, Gadegaard N, Lysdahl H, Lind M, Foldager CB. Surface chemistry, substrate, and topography guide the behavior of human articular chondrocytes cultured in vitro. J Biomed Mater Res A 2018; 106:2805-2816. [PMID: 29907992 DOI: 10.1002/jbm.a.36467] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/22/2018] [Accepted: 05/22/2018] [Indexed: 01/18/2023]
Abstract
Understanding the behavior of chondrocytes in contact with artificial culture surfaces is becoming increasingly important in attaining appropriate ex vivo culture conditions of chondrocytes in cartilage regeneration. Chondrocyte transplantation-based cartilage repair requires efficiently expanded chondrocytes, and the culture surface plays an important role in guiding the behavior of the cell. Micro- and nano-engineered surfaces make it possible to modulate cell behavior. We hypothesized that the combined influence of topography, substrate, and surface chemistry may affect the chondrocyte culturing in terms of proliferation and phenotypic means. Human chondrocytes were cultured on polystyrene fabricated microstructures, flat polydimethylsiloxane (PDMS), or polystyrene treated with fibronectin or oxygen plasma and cultured for 1, 4, 7, and 10 days. The behavior of chondrocytes was evaluated by proliferation, viability, chondrogenic gene expression, and cell morphology. Contrary to our hypothesis, microstructures in polystyrene did not significantly influence the behavior of chondrocytes neither under normoxic- nor hypoxic conditions. However, changes in the substrate stiffness and surface chemistry were found to influence cell viability, gene expression, and morphology of human chondrocytes. Oxygen plasma treatment was the most important parameter followed by the softer substrate type PDMS. The findings indicate the culture of human chondrocytes on softer substratum and surface activation by oxygen plasma may prevent dedifferentiation and may improve chondrocyte transplantation-based cartilage repair. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2805-2816, 2018.
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Affiliation(s)
| | - Morten Foss
- Interdisciplinary Nanoscience Center, iNANO, University Aarhus, Aarhus, Denmark
| | - Anwer Saeed
- Division of Biomedical Engineering, University of Glasgow, Glasgow, G12 8LT, United Kingdom
| | - Nikolaj Gadegaard
- Division of Biomedical Engineering, University of Glasgow, Glasgow, G12 8LT, United Kingdom
| | - Helle Lysdahl
- Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Martin Lind
- Sports Trauma Clinic, Aarhus University Hospital, Aarhus, Denmark
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Krajewska-Włodarczyk M, Owczarczyk-Saczonek A, Placek W, Osowski A, Wojtkiewicz J. Articular Cartilage Aging-Potential Regenerative Capacities of Cell Manipulation and Stem Cell Therapy. Int J Mol Sci 2018; 19:E623. [PMID: 29470431 PMCID: PMC5855845 DOI: 10.3390/ijms19020623] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 02/11/2018] [Accepted: 02/16/2018] [Indexed: 12/13/2022] Open
Abstract
Changes in articular cartilage during the aging process are a stage of natural changes in the human body. Old age is the major risk factor for osteoarthritis but the disease does not have to be an inevitable consequence of aging. Chondrocytes are particularly prone to developing age-related changes. Changes in articular cartilage that take place in the course of aging include the acquisition of the senescence-associated secretory phenotype by chondrocytes, a decrease in the sensitivity of chondrocytes to growth factors, a destructive effect of chronic production of reactive oxygen species and the accumulation of the glycation end products. All of these factors affect the mechanical properties of articular cartilage. A better understanding of the underlying mechanisms in the process of articular cartilage aging may help to create new therapies aimed at slowing or inhibiting age-related modifications of articular cartilage. This paper presents the causes and consequences of cellular aging of chondrocytes and the biological therapeutic outlook for the regeneration of age-related changes of articular cartilage.
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Affiliation(s)
- Magdalena Krajewska-Włodarczyk
- Department of Rheumatology, Municipal Hospital in Olsztyn, 10-900 Olsztyn, Poland.
- Department of Internal Medicine, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-900 Olsztyn, Poland.
- Department of Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-900 Olsztyn, Poland.
| | - Agnieszka Owczarczyk-Saczonek
- Department of Dermatology, Sexually Transmitted Diseases and Clinical Immunology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-900 Olsztyn, Poland.
| | - Waldemar Placek
- Department of Dermatology, Sexually Transmitted Diseases and Clinical Immunology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-900 Olsztyn, Poland.
| | - Adam Osowski
- Department of Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-900 Olsztyn, Poland.
| | - Joanna Wojtkiewicz
- Department of Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-900 Olsztyn, Poland.
- Laboratory for Regenerative Medicine, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-900 Olsztyn, Poland.
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9
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Huang X, Hou Y, Zhong L, Huang D, Qian H, Karperien M, Chen W. Promoted Chondrogenesis of Cocultured Chondrocytes and Mesenchymal Stem Cells under Hypoxia Using In-situ Forming Degradable Hydrogel Scaffolds. Biomacromolecules 2017; 19:94-102. [PMID: 29211452 DOI: 10.1021/acs.biomac.7b01271] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We investigated the effects of different oxygen tension (21% and 2.5% O2) on the chondrogenesis of different cell systems cultured in pH-degradable PVA hydrogels, including human articular chondrocytes (hACs), human mesenchymal stem cells (hMSCs), and their cocultures with a hAC/hMSC ratio of 20/80. These hydrogels were prepared with vinyl ether acrylate-functionalized PVA (PVA-VEA) and thiolated PVA-VEA (PVA-VEA-SH) via Michael-type addition reaction. The rheology tests determined the gelation of the hydrogels was controlled within 2-7 min, dependent on the polymer concentrations. The different cell systems were cultured in the hydrogel scaffolds for 5 weeks, and the safranin O and GAG assay showed that hypoxia (2.5% O2) greatly promoted the cartilage matrix production with an order of hAC > hAC/hMSC > hMSC. The real time quantitative PCR (RT-PCR) revealed that the hMSC group exhibited the highest hypertrophic marker gene expression (COL10A1, ALPL, MMP13) as well as the dedifferentiated marker gene expression (COL1A1) under normoxia conditions (21% O2), while these expressions were greatly inhibited by coculturing with a 20% amount of hACs and significantly further repressed under hypoxia conditions, which was comparative to the sole hAC group. The enzyme-linked immunosorbent assay (ELISA) also showed that coculture of hMSC/hAC greatly reduced the catabolic gene expression of MMP1 and MMP3 compared with the hMSC group. It is obvious that the hypoxia conditions promoted the chondrogenesis of hMSC by adding a small amount of hACs, and also effectively inhibited their hypotrophy. We are convinced that coculture of hAC/hMSC using in situ forming hydrogel scaffolds is a promising approach to producing cell source for cartilage engineering without the huge needs of primary chondrocyte harvest and expansion.
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Affiliation(s)
- Xiaobin Huang
- Department of Developmental BioEngineering, MIRA-Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Yong Hou
- Institute of Chemistry and Biochemistry, Freie Universität Berlin , Takustrasse 3, Berlin 14195, Germany
| | - LeiLei Zhong
- Department of Developmental BioEngineering, MIRA-Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Dechun Huang
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University , Nanjing 210009, People's Republic of China
| | - Hongliang Qian
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University , Nanjing 210009, People's Republic of China
| | - Marcel Karperien
- Department of Developmental BioEngineering, MIRA-Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Wei Chen
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University , Nanjing 210009, People's Republic of China.,Institute of Chemistry and Biochemistry, Freie Universität Berlin , Takustrasse 3, Berlin 14195, Germany
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Jeyakumar V, Niculescu-Morzsa E, Bauer C, Lacza Z, Nehrer S. Platelet-Rich Plasma Supports Proliferation and Redifferentiation of Chondrocytes during In Vitro Expansion. Front Bioeng Biotechnol 2017; 5:75. [PMID: 29270404 PMCID: PMC5723650 DOI: 10.3389/fbioe.2017.00075] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 11/23/2017] [Indexed: 01/05/2023] Open
Abstract
Articular cartilage regeneration is insufficient to restore sports injuries or defects that can occur from trauma. Treatment options for cartilage repair include autologous chondrocyte implantation (ACI) by isolation, expansion, and reimplantation of healthy donor chondrocytes. Chondrocyte expansion onto 2D substrates leads to dedifferentiation and loss of the cellular phenotype. We aimed to overcome the state of dedifferentiation by biochemical stimuli with platelet derivatives such as platelet-rich plasma (PRP) and hyperacute serum (HAS) to achieve sufficient cell numbers in combination with variable oxygen tension. Human articular chondrocytes from osteoarthritic (OA) cartilage chondrocytes were switched from 10% FCS supplementation to either 10% PRP or 10% HAS after initial passaging for further experiments under normoxic (20% O2) or hypoxic (1% O2) conditions. An XTT assay measured the effect of PRP or HAS on the cell proliferation at 3, 6, and 9 days. The chondrogenic redifferentiation potential of dedifferentiated chondrocytes was determined with reverse transcriptase quantitative real-time PCR for markers of expression for type II collagen (COL2A1), type I collagen (COL1A1), and matrix metalloproteinases MMP3, matrix metalloproteinase 13 (MMP13) at 24 and 72 h. Measured protein levels of 100% PRP or HAS by multiplex quantification revealed basic fibroblast growth factor, G-CSF, and PDGF were significantly higher in PRP than in HAS (p < 0.05) but LEPTIN levels did not differ. The quantified protein levels did not differ when isolated from same donors at a different time. Chondrocyte proliferation indicated that supplementation of 10% HAS enhanced the proliferation rate compared to 10% PRP or 10% FCS at 6 and 9 days significantly (p < 0.05). mRNA levels for expression of COL1A1 were significantly downregulated (p < 0.05) when cultured with 10% PRP than 10% HAS or 10% FCS under normoxic/hypoxic conditions. COL2A1 was significantly upregulated (p < 0.05) in PRP than 10% HAS or 10% FCS. MMP3 expression was downregulated after 72 h under all conditions. MMP13 was upregulated with 10% PRP at both 24 and 72 h but significantly downregulated under hypoxia (1% O2) for all circumstances. While HAS has its effect on chondrocyte proliferation, PRP enhances both proliferation and redifferentiation of dedifferentiated chondrocytes. PRP can replace standard usage of FCS for chondrogenic priming and expansion as implications for clinical use such as ACI procedures.
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Affiliation(s)
- Vivek Jeyakumar
- Centre for Regenerative Medicine and Orthopedics, Danube University Krems, Krems an der Donau, Austria
| | - Eugenia Niculescu-Morzsa
- Centre for Regenerative Medicine and Orthopedics, Danube University Krems, Krems an der Donau, Austria
| | - Christoph Bauer
- Centre for Regenerative Medicine and Orthopedics, Danube University Krems, Krems an der Donau, Austria
| | | | - Stefan Nehrer
- Centre for Regenerative Medicine and Orthopedics, Danube University Krems, Krems an der Donau, Austria
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11
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The Signaling Pathways Involved in Chondrocyte Differentiation and Hypertrophic Differentiation. Stem Cells Int 2016; 2016:2470351. [PMID: 28074096 PMCID: PMC5198191 DOI: 10.1155/2016/2470351] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Accepted: 11/22/2016] [Indexed: 12/19/2022] Open
Abstract
Chondrocytes communicate with each other mainly via diffusible signals rather than direct cell-to-cell contact. The chondrogenic differentiation of mesenchymal stem cells (MSCs) is well regulated by the interactions of varieties of growth factors, cytokines, and signaling molecules. A number of critical signaling molecules have been identified to regulate the differentiation of chondrocyte from mesenchymal progenitor cells to their terminal maturation of hypertrophic chondrocytes, including bone morphogenetic proteins (BMPs), SRY-related high-mobility group-box gene 9 (Sox9), parathyroid hormone-related peptide (PTHrP), Indian hedgehog (Ihh), fibroblast growth factor receptor 3 (FGFR3), and β-catenin. Except for these molecules, other factors such as adenosine, O2 tension, and reactive oxygen species (ROS) also have a vital role in cartilage formation and chondrocyte maturation. Here, we outlined the complex transcriptional network and the function of key factors in this network that determine and regulate the genetic program of chondrogenesis and chondrocyte differentiation.
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Kean TJ, Mera H, Whitney GA, MacKay DL, Awadallah A, Fernandes RJ, Dennis JE. Disparate response of articular- and auricular-derived chondrocytes to oxygen tension. Connect Tissue Res 2016; 57:319-33. [PMID: 27128439 PMCID: PMC4984267 DOI: 10.1080/03008207.2016.1182996] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE/AIM To determine the effect of reduced (5%) oxygen tension on chondrogenesis of auricular-derived chondrocytes. Currently, many cell and tissue culture experiments are performed at 20% oxygen with 5% carbon dioxide. Few cells in the body are subjected to this supra-physiological oxygen tension. Chondrocytes and their mesenchymal progenitors are widely reported to have greater chondrogenic expression when cultured at low, more physiological, oxygen tension (1-7%). Although generally accepted, there is still some controversy, and different culture methods, species, and outcome metrics cloud the field. These results are, however, articular chondrocyte biased and have not been reported for auricular-derived chondrocytes. MATERIALS AND METHODS Auricular and articular chondrocytes were isolated from skeletally mature New Zealand White rabbits, expanded in culture and differentiated in high density cultures with serum-free chondrogenic media. Cartilage tissue derived from aggregate cultures or from the tissue engineered sheets were assessed for biomechanical, glycosaminoglycan, collagen, collagen cross-links, and lysyl oxidase activity and expression. RESULTS Our studies show increased proliferation rates for both auricular and articular chondrocytes at low (5%) O2 versus standard (20%) O2. In our scaffold-free chondrogenic cultures, low O2 was found to increase articular chondrocyte accumulation of glycosaminoglycan, but not cross-linked type II collagen, or total collagen. Conversely, auricular chondrocytes accumulated less glycosaminoglycan, cross-linked type II collagen and total collagen under low oxygen tension. CONCLUSIONS This study highlights the dramatic difference in response to low O2 of chondrocytes isolated from different anatomical sites. Low O2 is beneficial for articular-derived chondrogenesis but detrimental for auricular-derived chondrogenesis.
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Affiliation(s)
- Thomas J. Kean
- Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA,Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA,Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA
| | - Hisashi Mera
- Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA,Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA,Department of Health and Sports Sciences, Mukogawa Women’s University, Hyogo, Japan
| | - G. Adam Whitney
- Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA,Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA
| | - Danielle L. MacKay
- Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA,Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA
| | - Amad Awadallah
- Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA
| | - Russell J. Fernandes
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, WA, USA
| | - James E. Dennis
- Matrix Biology Program, Benaroya Research Institute at Virginia Mason, Seattle, WA, USA,Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA,Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA
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Lynch B, Crawford K, Baruti O, Abdulahad A, Webster M, Puetzer J, Ryu C, Bonassar LJ, Mendenhall J. The effect of hypoxia on thermosensitive poly(N
-vinylcaprolactam) hydrogels with tunable mechanical integrity for cartilage tissue engineering. J Biomed Mater Res B Appl Biomater 2016; 105:1863-1873. [DOI: 10.1002/jbm.b.33705] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 02/25/2016] [Accepted: 04/21/2016] [Indexed: 02/04/2023]
Affiliation(s)
- Brandon Lynch
- Department of Chemistry; Morehouse College; Atlanta Georgia
| | | | - Omari Baruti
- Department of Chemistry; Morehouse College; Atlanta Georgia
| | - Asem Abdulahad
- Department of Chemistry and Chemical Biology; Rensselaer Polytechnic Institute; Troy New York
| | | | - Jennifer Puetzer
- Department of Biomedical Engineering; Cornell University; Ithaca New York
| | - Chang Ryu
- Department of Chemistry and Chemical Biology; Rensselaer Polytechnic Institute; Troy New York
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Synergistic effects of hypoxia and morphogenetic factors on early chondrogenic commitment of human embryonic stem cells in embryoid body culture. Stem Cell Rev Rep 2016; 11:228-41. [PMID: 25618295 DOI: 10.1007/s12015-015-9584-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Derivation of articular chondrocytes from human stem cells would advance our current understanding of chondrogenesis, and accelerate development of new stem cell therapies for cartilage repair. Chondrogenic differentiation of human embryonic stem cells (hESCs) has been studied using supplemental and cell-secreted morphogenetic factors. The use of bioreactors enabled insights into the effects of physical forces and controlled oxygen tension. In this study, we investigated the interactive effects of controlled variation of oxygen tension and chondrocyte-secreted morphogenetic factors on chondrogenic differentiation of hESCs in the embryoid body format (hESC-EB). Transient hypoxic culture (2 weeks at 5 % O2 followed by 1 week at 21 % O2) of hESC-EBs in medium conditioned with primary chondrocytes up-regulated the expression of SOX9 and suppressed pluripotent markers OCT4 and NANOG. Pellets derived from these cells showed significant up-regulation of chondrogenic genes (SOX9, COL2A1, ACAN) and enhanced production of cartilaginous matrix (collagen type II and proteoglycan) as compared to the pellets from hESC-EBs cultured under normoxic conditions. Gene expression profiles corresponded to those associated with native cartilage development, with early expression of N-cadherin (indicator of cell condensation) and late expression of aggrecan (ACAN, indicator of proteoglycan production). When implanted into highly vascularized subcutaneous area in immunocompromised mice for 4 weeks, pellets remained phenotypically stable and consisted of cartilaginous extracellular matrix (ECM), without evidence of dedifferentiation or teratoma formation. Based on these results, we propose that chondrogenesis in hESC can be synergistically enhanced by a control of oxygen tension and morphogenetic factors secreted by chondrocytes.
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Synoviocyte Derived-Extracellular Matrix Enhances Human Articular Chondrocyte Proliferation and Maintains Re-Differentiation Capacity at Both Low and Atmospheric Oxygen Tensions. PLoS One 2015; 10:e0129961. [PMID: 26075742 PMCID: PMC4468209 DOI: 10.1371/journal.pone.0129961] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 05/14/2015] [Indexed: 11/22/2022] Open
Abstract
Background Current tissue engineering methods are insufficient for total joint resurfacing, and chondrocytes undergo de-differentiation when expanded on tissue culture plastic. De-differentiated chondrocytes show poor re-differentiation in culture, giving reduced glycosaminoglycan (GAG) and collagen matrix accumulation. To address this, porcine synoviocyte-derived extracellular matrix and low (5%) oxygen tension were assessed for their ability to enhance human articular chondrocyte expansion and maintain re-differentiation potential. Methods Porcine synoviocyte matrices were devitalized using 3 non-detergent methods. These devitalized synoviocyte matrices were compared against tissue culture plastic for their ability to support human chondrocyte expansion. Expansion was further compared at both low (5%), and atmospheric (20%) oxygen tension on all surfaces. Expanded cells then underwent chondrogenic re-differentiation in aggregate culture at both low and atmospheric oxygen tension. Aggregates were assessed for their GAG and collagen content both biochemically and histologically. Results Human chondrocytes expanded twice as fast on devitalized synoviocyte matrix vs. tissue culture plastic, and cells retained their re-differentiation capacity for twice the number of population doublings. There was no significant difference in growth rate between low and atmospheric oxygen tension. There was significantly less collagen type I, collagen type II, aggrecan and more MMP13 expression in cells expanded on synoviocyte matrix vs. tissue culture plastic. There were also significant effects due to oxygen tension on gene expression, wherein there was greater collagen type I, collagen type II, SOX9 and less MMP13 expression on tissue culture plastic compared to synoviocyte matrix. There was a significant increase in GAG, but not collagen, accumulation in chondrocyte aggregates re-differentiated at low oxygen tension over that achieved in atmospheric oxygen conditions. Conclusions Synoviocyte-derived matrix supports enhanced expansion of human chondrocytes such that the chondrocytes are maintained in a state from which they can re-differentiate into a cartilage phenotype after significantly more population doublings. Also, low oxygen tension supports GAG, but not collagen, accumulation. These findings are a step towards the production of a more functional, tissue engineered cartilage.
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16
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Tekari A, Luginbuehl R, Hofstetter W, Egli RJ. Transforming growth factor beta signaling is essential for the autonomous formation of cartilage-like tissue by expanded chondrocytes. PLoS One 2015; 10:e0120857. [PMID: 25775021 PMCID: PMC4361600 DOI: 10.1371/journal.pone.0120857] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/27/2015] [Indexed: 02/07/2023] Open
Abstract
Cartilage is a tissue with limited self-healing potential. Hence, cartilage defects require surgical attention to prevent or postpone the development of osteoarthritis. For cell-based cartilage repair strategies, in particular autologous chondrocyte implantation, articular chondrocytes are isolated from cartilage and expanded in vitro to increase the number of cells required for therapy. During expansion, the cells lose the competence to autonomously form a cartilage-like tissue, that is in the absence of exogenously added chondrogenic growth factors, such as TGF-βs. We hypothesized that signaling elicited by autocrine and/or paracrine TGF-β is essential for the formation of cartilage-like tissue and that alterations within the TGF-β signaling pathway during expansion interfere with this process. Primary bovine articular chondrocytes were harvested and expanded in monolayer culture up to passage six and the formation of cartilage tissue was investigated in high density pellet cultures grown for three weeks. Chondrocytes expanded for up to three passages maintained the potential for autonomous cartilage-like tissue formation. After three passages, however, exogenous TGF-β1 was required to induce the formation of cartilage-like tissue. When TGF-β signaling was blocked by inhibiting the TGF-β receptor 1 kinase, the autonomous formation of cartilage-like tissue was abrogated. At the initiation of pellet culture, chondrocytes from passage three and later showed levels of transcripts coding for TGF-β receptors 1 and 2 and TGF-β2 to be three-, five- and five-fold decreased, respectively, as compared to primary chondrocytes. In conclusion, the autonomous formation of cartilage-like tissue by expanded chondrocytes is dependent on signaling induced by autocrine and/or paracrine TGF-β. We propose that a decrease in the expression of the chondrogenic growth factor TGF-β2 and of the TGF-β receptors in expanded chondrocytes accounts for a decrease in the activity of the TGF-β signaling pathway and hence for the loss of the potential for autonomous cartilage-like tissue formation.
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Affiliation(s)
- Adel Tekari
- Group for Bone Biology & Orthopaedic Research, Department Clinical Research, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | | | - Willy Hofstetter
- Group for Bone Biology & Orthopaedic Research, Department Clinical Research, University of Bern, Bern, Switzerland
| | - Rainer J. Egli
- Group for Bone Biology & Orthopaedic Research, Department Clinical Research, University of Bern, Bern, Switzerland
- RMS Foundation, Bettlach, Switzerland
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Tekari A, Luginbuehl R, Hofstetter W, Egli RJ. Chondrocytes expressing intracellular collagen type II enter the cell cycle and co-express collagen type I in monolayer culture. J Orthop Res 2014; 32:1503-11. [PMID: 25043137 DOI: 10.1002/jor.22690] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 06/17/2014] [Indexed: 02/04/2023]
Abstract
For autologous chondrocyte transplantation, articular chondrocytes are harvested from cartilage tissue and expanded in vitro in monolayer culture. We aimed to characterize with a cellular resolution the synthesis of collagen type II (COL2) and collagen type I (COL1) during expansion in order to further understand why these cells lose the potential to form cartilage tissue when re-introduced into a microenvironment that supports chondrogenesis. During expansion for six passages, levels of transcripts encoding COL2 decreased to <0.1%, whereas transcript levels encoding COL1 increased 370-fold as compared to primary chondrocytes. Flow cytometry for intracellular proteins revealed that chondrocytes acquired a COL2/COL1-double positive phenotype during expansion, and the COL2 positive cells were able to enter the cell cycle. While the fraction of COL2 positive cells decreased from 70% to <2% in primary chondrocytes to passage six cells, the fraction of COL1 positive cells increased from <1% to >95%. In parallel to the decrease of the fraction of COL2 positive cells, the cells' potential to form cartilage-like tissue in pellet cultures steadily decreased. Intracellular staining for COL2 enables for characterization of chondrocyte lineage cells in more detail with a cellular resolution, and it may allow predicting the effectiveness of expanded chondrocytes to form cartilage-like tissue.
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Affiliation(s)
- Adel Tekari
- Group for Bone Biology and Orthopaedic Research, Department Clinical Research, University of Bern, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
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Hubka KM, Dahlin RL, Meretoja VV, Kasper FK, Mikos AG. Enhancing chondrogenic phenotype for cartilage tissue engineering: monoculture and coculture of articular chondrocytes and mesenchymal stem cells. TISSUE ENGINEERING PART B-REVIEWS 2014; 20:641-54. [PMID: 24834484 DOI: 10.1089/ten.teb.2014.0034] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Articular cartilage exhibits an inherently low rate of regeneration. Consequently, damage to articular cartilage often requires surgical intervention. However, existing treatments generally result in the formation of fibrocartilage tissue, which is inferior to native articular cartilage. As a result, cartilage engineering strategies seek to repair or replace damaged cartilage with an engineered tissue that restores full functionality to the impaired joint. These strategies often involve the use of chondrocytes, yet in vitro expansion and culture can lead to undesirable changes in chondrocyte phenotype. This review focuses on the use of articular chondrocytes and mesenchymal stem cells (MSCs) in either monoculture or coculture for the enhancement of chondrogenesis. Coculture strategies increasingly outperform their monoculture counterparts with regard to chondrogenesis and present unique opportunities to attain chondrocyte phenotype stability in vitro. Methods to prevent chondrocyte dedifferentiation and promote chondrocyte redifferentiation as well as to promote the chondrogenic differentiation of MSCs while preventing MSC hypertrophy are discussed.
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Affiliation(s)
- Kelsea M Hubka
- Department of Bioengineering, Rice University , Houston, Texas
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19
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Chan LLY, Huang J, Hagiwara Y, Aguila L, Rowe D. Discriminating multiplexed GFP reporters in primary articular chondrocyte cultures using image cytometry. J Fluoresc 2014; 24:1041-53. [PMID: 24728974 DOI: 10.1007/s10895-014-1383-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Accepted: 03/20/2014] [Indexed: 11/25/2022]
Abstract
Flow cytometry has become a standard tool for defining a heterogeneous cell population based on surface expressed epitopes or GFP reporters that reflect cell types or cellular differentiation. The introduction of image cytometry raised the possibility of adaptation to discriminate GFP reporters used to appreciate cell heterogeneity within the skeletal lineages. The optical filters and LEDs were optimized for the reporters used in transgenic mice expressing various fluorescent proteins. In addition, the need for compensation between eGFP and surrounding reporters due to optical cross-talk was eliminated by selecting the appropriate excitation and emission filters. Bone marrow or articular cartilage cell cultures from GFP and RFP reporter mouse lines were established to demonstrate the equivalency in functionalities of image to flow cytometry analysis. To examine the ability for monitoring primary cell differentiation, articular chondrocyte cell cultures were established from mice that were single or doubly transgenic (Dkk3eGFP and Col2A1GFPcyan), which identify the progression of superficial small articular cell to a mature chondrocyte. The instrument was able to rapidly and accurately discriminate cells that were Dkk3eGFP only, Dkk3eGFP/Col2A1GFPcyan, and Col2A1GFP, which provides a useful tool for studying the impact of culture conditions on lineage expansion and differentiation.
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Affiliation(s)
- Leo Li-Ying Chan
- Department of Technology R&D, Nexcelom Bioscience LLC, 360 Merrimack St. Building 9, Lawrence, MA, 01843, USA,
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20
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Hypoxia enhances chondrogenic differentiation of human adipose tissue-derived stromal cells in scaffold-free and scaffold systems. Cell Tissue Res 2013; 355:89-102. [PMID: 24178804 DOI: 10.1007/s00441-013-1732-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 09/05/2013] [Indexed: 02/05/2023]
Abstract
Human adipose-derived stromal cells (hASCs) possess the potential for chondrogenic differentiation. Recent studies imply that this differentiation process may be enhanced by culturing the cells in low oxygen tension in combination with three-dimensional (3D) scaffolds. We report the evaluation of the chondrogenic potential of hASC pellets in 5 and 21% O2 and as cell-scaffold constructs using a collagen I/III scaffold with chemical induction using TGF-β3. hASCs from four human donors were cultured both in a micromass pellet system and in 3D collagen I/III scaffolds in either 5 or 21% O2. Chondrogenesis was evaluated by quantitative gene expression analysis of aggrecan, SOX9, collagen I, II and X and histological evaluation with H&E and toluidine blue staining. Induced pellets cultured in 5% O2 showed increased peripheral cellularity and matrix deposition compared with 21% O2. Induced pellets cultured in 5% O2 had increased control-adjusted gene expression of aggrecan, SOX9 and collagen I and decreased collagen X compared with 21% O2 cultures. Induced pellets had higher gene expression of aggrecan, SOX9, collagen I, II and X and increased ratios of collagen II/I and collagen II/X compared with controls. As for pellets, scaffold cultures showed cellularity and matrix deposition organized in a zonal manner as a function of the oxygen tension, with a cartilage-like morphology and matrix deposition peripherally in the 5% O2 group and a more centrally located matrix in the 21% O2 group. There were no differences in histology and gene expressions between pellet and scaffold cultures. Five percent O2 in combination with chondrogenic culture medium stimulated chondrogenic differentiation of hASCs in vitro. We observed similar patterns of differentiation and matrix disposition in pellet and scaffold cultures.
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21
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Meretoja VV, Dahlin RL, Wright S, Kasper FK, Mikos AG. The effect of hypoxia on the chondrogenic differentiation of co-cultured articular chondrocytes and mesenchymal stem cells in scaffolds. Biomaterials 2013; 34:4266-73. [PMID: 23489925 DOI: 10.1016/j.biomaterials.2013.02.064] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 02/24/2013] [Indexed: 12/28/2022]
Abstract
In this work, we investigated the effects of lowered oxygen tension (20% and 5% O2) on the chondrogenesis and hypertrophy of articular chondrocytes (ACs), mesenchymal stem cells (MSCs) and their co-cultures with a 30:70 AC:MSC ratio. Cells were cultured for six weeks within porous scaffolds, and their cellularity, cartilaginous matrix production (collagen II/I expression ratio, hydroxyproline and GAG content) and hypertrophy markers (collagen X expression, ALP activity, calcium accumulation) were analyzed. After two weeks, hypoxic culture conditions had expedited chondrogenesis with all cell types by increasing collagen II/I expression ratio and matrix synthesis by ~2.5-11 and ~1.5-3.0 fold, respectively. At later times, hypoxia decreased cellularity but had little effect on matrix synthesis. ACs and co-cultures showed similarly high collagen II/I expression ratio and GAG rich matrix formation, whereas MSCs produced the least hyaline cartilage-like matrix and obtained a hypertrophic phenotype with eventual calcification. MSC hypertrophy was further emphasized in hypoxic conditions. We conclude that the most promising cell source for cartilage engineering was co-cultures, as they have a potential to decrease the need for primary chondrocyte harvest and expansion while obtaining a stable highly chondrogenic phenotype independent of the oxygen tension in the cultures.
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Affiliation(s)
- Ville V Meretoja
- Department of Bioengineering, Rice University, Houston, TX 77005, USA
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22
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O'hEireamhoin S, Buckley CT, Jones E, McGonagle D, Mulhall KJ, Kelly DJ. Recapitulating aspects of the oxygen and substrate environment of the damaged joint milieu for stem cell-based cartilage tissue engineering. Tissue Eng Part C Methods 2012; 19:117-27. [PMID: 22834895 DOI: 10.1089/ten.tec.2012.0142] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human infrapatellar fat pad contains a source of mesenchymal stem cells (FPSCs) that potentially offer a novel population for the treatment of damaged or diseased articular cartilage. Existing cartilage repair strategies such as microfracture harness the presence of a low-oxygen microenvironment, fibrin clot formation at sites of microfracture, and elevations in growth factors in the damaged joint milieu. Bearing this in mind, the objective of this study was to determine the chondrogenic potential of diseased human FPSCs in a model system that recapitulates some of these features. In the first phase of the study, the role of transforming growth factor beta-3 (TGF-β3) and fibroblast growth factor-2 (FGF-2), in addition to an altered oxygen-tension environment, on the colony-forming unit-fibroblast (CFU-F) capacity and growth kinetics of human FPSCs during monolayer expansion was evaluated. The subsequent chondrogenic capacity of these cells was quantified in both normoxic (20%) and low- (5%) oxygen conditions. Expansion in FGF-2 was shown to reduce CFU-F numbers, but simultaneously increase both the colony size and the cell yield compared to standard expansion conditions. Supplementation with both FGF-2 and TGF-β3 significantly reduced cell-doubling time. Expansion in FGF-2, followed by differentiation at 5% oxygen tension, was observed to synergistically enhance subsequent sulfated glycosaminoglycan (sGAG) accumulation after chondrogenic induction. FPSCs expanded in FGF-2 were then encapsulated in either agarose or fibrin hydrogels in an attempt to engineer cartilaginous grafts. sGAG synthesis was higher in fibrin constructs, and was further enhanced by differentiation at 5% oxygen tension, accumulating 2.7% (ww) sGAG after 42 days in culture. These results indicate that FPSCs, a readily accessible cell population, form cartilage in an in vitro environment that recapitulates several key biological features of cartilage repair during microfracture and also point toward the potential utility of such cells when combined with fibrin hydrogel scaffolds.
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Affiliation(s)
- Sven O'hEireamhoin
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
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Muzzarelli RAA, Greco F, Busilacchi A, Sollazzo V, Gigante A. Chitosan, hyaluronan and chondroitin sulfate in tissue engineering for cartilage regeneration: a review. Carbohydr Polym 2012; 89:723-39. [PMID: 24750856 DOI: 10.1016/j.carbpol.2012.04.057] [Citation(s) in RCA: 296] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 04/23/2012] [Accepted: 04/25/2012] [Indexed: 12/22/2022]
Abstract
Injection of hyaluronan into osteoarthritic joints restores the viscoelasticity, augments the flow of joint fluid, normalizes endogenous hyaluronan synthesis, and improves joint function. Chitosan easily forms polyelectrolyte complexes with hyaluronan and chondroitin sulfate. Synergy of chitosan with hyaluronan develops enhanced performances in regenerating hyaline cartilage, typical results being structural integrity of the hyaline-like neocartilage, and reconstitution of the subchondral bone, with positive cartilage staining for collagen-II and GAG in the treated sites. Chitosan qualifies for the preparation of scaffolds intended for the regeneration of cartilage: it yields mesoporous cryogels; it provides a friendly environment for chondrocytes to propagate, produce typical ECM, and assume the convenient phenotype; it is a good carrier for growth factors; it inactivates metalloproteinases thus preventing collagen degradation; it is suitable for the induction of the chondrogenic differentiation of mesenchymal stem cells; it is a potent means for hemostasis and platelet delivery.
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Affiliation(s)
- Riccardo A A Muzzarelli
- Clinical Orthopaedics, Department of Clinical and Experimental Sciences, Polytechnic University Delle Marche, Via Tronto 10-A, IT-60126 Ancona, Italy
| | - Francesco Greco
- Clinical Orthopaedics, Department of Clinical and Experimental Sciences, Polytechnic University Delle Marche, Via Tronto 10-A, IT-60126 Ancona, Italy
| | - Alberto Busilacchi
- Clinical Orthopaedics, Department of Clinical and Experimental Sciences, Polytechnic University Delle Marche, Via Tronto 10-A, IT-60126 Ancona, Italy
| | - Vincenzo Sollazzo
- Department of Orthopaedics, University of Ferrara, Corso Giovecca 203, IT-44100 Ferrara, Italy
| | - Antonio Gigante
- Clinical Orthopaedics, Department of Clinical and Experimental Sciences, Polytechnic University Delle Marche, Via Tronto 10-A, IT-60126 Ancona, Italy
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Five percent oxygen tension is not beneficial for neocartilage formation in scaffold-free cell cultures. Cell Tissue Res 2012; 348:109-17. [DOI: 10.1007/s00441-012-1366-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 02/07/2012] [Indexed: 10/28/2022]
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Egli RJ, Wernike E, Grad S, Luginbühl R. Physiological cartilage tissue engineering effect of oxygen and biomechanics. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 289:37-87. [PMID: 21749898 DOI: 10.1016/b978-0-12-386039-2.00002-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In vitro engineering of cartilaginous tissues has been studied for many years, and tissue-engineered constructs are sought to be used clinically for treating articular cartilage defects. Even though there is a plethora of studies and data available, no breakthroughs have been achieved yet that allow for implanting in vivo cultured articular cartilaginous tissues in patients. A review of contributions to cartilage tissue engineering over the past decades emphasizes that most of the studies were performed under environmental conditions neglecting the physiological situation. This is specifically pronounced in the use of bioreactor systems which neither allow for application of near physiomechanical stimulations nor for controlling a hypoxic environment as it is experienced in synovial joints. It is suspected that the negligence of these important parameters has slowed down progress and prevented major breakthroughs in the field. This review focuses on the main aspects of cartilage tissue engineering with emphasis on the relation and understanding of employing physiological conditions.
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Scotti C, Osmokrovic A, Wolf F, Miot S, Peretti GM, Barbero A, Martin I. Response of human engineered cartilage based on articular or nasal chondrocytes to interleukin-1β and low oxygen. Tissue Eng Part A 2011; 18:362-72. [PMID: 21902467 DOI: 10.1089/ten.tea.2011.0234] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Previous studies showed that human nasal chondrocytes (HNC) exhibit higher proliferation and chondrogenic capacity as compared to human articular chondrocytes (HAC). To consider HNC as a relevant alternative cell source for the repair of articular cartilage defects it is necessary to test how these cells react when exposed to environmental factors typical of an injured joint. We thus aimed this study at investigating the responses of HNC and HAC to exposure to interleukin (IL)-1β and low oxygen. For this purpose HAC and HNC harvested from the same donors (N=5) were expanded in vitro and then cultured in pellets or collagen-based scaffolds at standard (19%) or low oxygen (5%) conditions. Resulting tissues were analyzed after a short (3 days) exposure to IL-1β, mimicking the initially inflammatory implantation site, or following a recovery time (1 or 2 weeks for pellets and scaffolds, respectively). After IL-1β treatment, constructs generated by both HAC and HNC displayed a transient loss of GAG (up to 21.8% and 36.8%, respectively) and, consistently, an increased production of metalloproteases (MMP)-1 and -13. Collagen type II and the cryptic fragment of aggrecan (DIPEN), both evaluated immunohistochemically, displayed a trend consistent with GAG and MMPs production. HNC-based constructs exhibited a more efficient recovery upon IL-1β withdrawal, resulting in a higher accumulation of GAG (up to 2.6-fold) compared to the corresponding HAC-based tissues. On the other hand, HAC displayed a positive response to low oxygen culture, while HNC were only slightly affected by oxygen percentage. Collectively, under the conditions tested mimicking the postsurgery articular environment, HNC retained a tissue-forming capacity, similar or even better than HAC. These results represent a step forward in validating HNC as a cell source for cartilage tissue engineering strategies.
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Affiliation(s)
- Celeste Scotti
- Departments of Surgery and of Biomedicine, University Hospital Basel, Basel, Switzerland
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Boström KI, Rajamannan NM, Towler DA. The regulation of valvular and vascular sclerosis by osteogenic morphogens. Circ Res 2011; 109:564-77. [PMID: 21852555 DOI: 10.1161/circresaha.110.234278] [Citation(s) in RCA: 200] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Vascular calcification increasingly afflicts our aging, dysmetabolic population. Once considered only a passive process of dead and dying cells, vascular calcification has now emerged as a highly regulated form of biomineralization organized by collagenous and elastin extracellular matrices. During skeletal bone formation, paracrine epithelial-mesenchymal and endothelial-mesenchymal interactions control osteochondrocytic differentiation of multipotent mesenchymal progenitor cells. These paracrine osteogenic signals, mediated by potent morphogens of the bone morphogenetic protein and wingless-type MMTV integration site family member (Wnt) superfamilies, are also active in the programming of arterial osteoprogenitor cells during vascular and valve calcification. Inflammatory cytokines, reactive oxygen species, and oxylipids-increased in the clinical settings of atherosclerosis, diabetes, and uremia that promote arteriosclerotic calcification-elicit the ectopic vascular activation of osteogenic morphogens. Specific extracellular and intracellular inhibitors of bone morphogenetic protein-Wnt signaling have been identified as contributing to the regulation of osteogenic mineralization during development and disease. These inhibitory pathways and their regulators afford the development of novel therapeutic strategies to prevent and treat valve and vascular sclerosis.
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Affiliation(s)
- Kristina I Boström
- Department of Medicine, Division of Cardiology, David Geffen School of Medicine at UCLA, 10833 LeConte Ave, Los Angeles, CA 90095, USA.
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Effects of oxygen and culture system on in vitro propagation and redifferentiation of osteoarthritic human articular chondrocytes. Cell Tissue Res 2011; 347:649-63. [PMID: 21638206 DOI: 10.1007/s00441-011-1193-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 05/12/2011] [Indexed: 02/06/2023]
Abstract
Regenerative medicine-based approaches for the repair of damaged cartilage rely on the ability to propagate cells while promoting their chondrogenic potential. Thus, conditions for cell expansion should be optimized through careful environmental control. Appropriate oxygen tension and cell expansion substrates and controllable bioreactor systems are probably critical for expansion and subsequent tissue formation during chondrogenic differentiation. We therefore evaluated the effects of oxygen and microcarrier culture on the expansion and subsequent differentiation of human osteoarthritic chondrocytes. Freshly isolated chondrocytes were expanded on tissue culture plastic or CultiSpher-G microcarriers under hypoxic or normoxic conditions (5% or 20% oxygen partial pressure, respectively) followed by cell phenotype analysis with flow cytometry. Cells were redifferentiated in micromass pellet cultures over 4 weeks, under either hypoxia or normoxia. Chondrocytes cultured on tissue culture plastic proliferated faster, expressed higher levels of cell surface markers CD44 and CD105 and demonstrated stronger staining for proteoglycans and collagen type II in pellet cultures compared with microcarrier-cultivated cells. Pellet wet weight, glycosaminoglycan content and expression of chondrogenic genes were significantly increased in cells differentiated under hypoxia. Hypoxia-inducible factor-3α mRNA was up-regulated in these cultures in response to low oxygen tension. These data confirm the beneficial influence of reduced oxygen on ex vivo chondrogenesis. However, hypoxia during cell expansion and microcarrier bioreactor culture does not enhance intrinsic chondrogenic potential. Further improvements in cell culture conditions are therefore required before chondrocytes from osteoarthritic and aged patients can become a useful cell source for cartilage regeneration.
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Henderson JH, Ginley NM, Caplan AI, Niyibizi C, Dennis JE. Low oxygen tension during incubation periods of chondrocyte expansion is sufficient to enhance postexpansion chondrogenesis. Tissue Eng Part A 2010; 16:1585-93. [PMID: 19958052 DOI: 10.1089/ten.tea.2009.0411] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To determine whether low oxygen (O(2)) tension during expansion affects the matrix density, as well as quantity, of cartilage formed, and to determine whether application of low O(2) tension during incubation periods alone is sufficient to modulate chondrogenic expression, rabbit chondrocytes expanded at either 21% O(2) or 5% O(2) were analyzed for glycosaminoglycan (GAG) and DNA content, total collagen, and gene expression during expansion and postexpansion aggregate cultures. When cultured as aggregates at 21% O(2), chondrocytes expanded at 5% O(2) produced cartilage aggregates that contained more total GAG, GAG per wet weight, GAG per DNA, and total collagen than chondrocytes expanded at 21% O(2). Less of an effect on GAG and collagen content was observed when aggregate culture was performed at 5% O(2). Real-time polymerase chain reaction analysis of COL2A1 expression showed upregulated levels of type IIA (an early marker) and IIB (a late marker) during expansion and elevated levels of type IIB during aggregate culture in chondrocytes expanded in low O(2). The application of low O(2) tension during incubation periods of chondrocyte expansion enhances the ultimate cartilage matrix density and quantity, and this enhancement can be achieved through the use of an O(2) control incubator.
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Affiliation(s)
- James H Henderson
- Department of Biology (Skeletal Research Center), Case Western Reserve University, Cleveland, OH, USA.
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Anabolic and catabolic responses of human articular chondrocytes to varying oxygen percentages. Arthritis Res Ther 2010; 12:R34. [PMID: 20193091 PMCID: PMC2888180 DOI: 10.1186/ar2942] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 02/09/2010] [Accepted: 03/02/2010] [Indexed: 11/10/2022] Open
Abstract
Introduction Oxygen is a critical parameter proposed to modulate the functions of chondrocytes ex-vivo as well as in damaged joints. This article investigates the effect of low (more physiological) oxygen percentage on the biosynthetic and catabolic activity of human articular chondrocytes (HAC) at different phases of in vitro culture. Methods HAC expanded in monolayer were cultured in pellets for two weeks (Phase I) or up to an additional two weeks (Phase II). In each Phase, cells were exposed to 19% or 5% oxygen. Resulting tissues and culture media were assessed to determine amounts of produced/released proteoglycans and collagens, metalloproteinases (MMPs), collagen degradation products and collagen fibril organization using biochemical, (immuno)-histochemical, gene expression and scanning electron microscopy analyses. In specific experiments, the hypoxia-inducible factor-1α (HIF-1α) inhibitor cadmium chloride was supplemented in the culture medium to assess the involvement of this pathway. Results Independent from the oxygen percentage during expansion, HAC cultured at 5% O2 (vs 19% O2) during Phase I accumulated higher amounts of glycosaminoglycans and type II collagen and expressed reduced levels of MMP-1 and MMP-13 mRNA and protein. Switching to 19% oxygen during Phase II resulted in reduced synthesis of proteoglycan and collagen, increased release of MMPs, accumulation of type II collagen fragments and higher branching of collagen fibrils. In contrast, reducing O2 during Phase II resulted in increased proteoglycan and type II collagen synthesis and reduced expression and release of MMP-13 mRNA and protein. Supplementation of cadmium chloride during differentiation culture at 5% O2 drastically reduced the up-regulation of type II collagen and the down-regulation of MMP-1 mRNA. Conclusions The application of more physiologic oxygen percentage during specific phases of differentiation culture enhanced the biosynthetic activity and reduced the activity of catabolic enzymes implicated in cartilage breakdown. Modulation of the oxygen percentage during HAC culture may be used to study pathophysiological events occurring in osteoarthritis and to enhance properties of in vitro engineered cartilaginous tissues.
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Boubriak OA, Brooks JTS, Urban JPG. Cytochrome c oxidase levels in chondrocytes during monolayer expansion and after return to three dimensional culture. Osteoarthritis Cartilage 2009; 17:1084-92. [PMID: 19303470 DOI: 10.1016/j.joca.2009.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Revised: 02/12/2009] [Accepted: 03/04/2009] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Here we investigate whether monolayer culture or culture at 21% oxygen influences activity of cytochrome c oxidase, the terminal enzyme in the respiratory chain whose activity is essential for oxidative metabolism and whether return to three dimensional (3-D) culture restores cytochrome c oxidase activity to original levels. METHODS Primary bovine articular chondrocytes were cultured in alginate beads (3-D) for 4 weeks or in monolayer under 1% and 21% oxygen for up to 9 days and then returned to 3-D culture for up to 4 weeks. Cells were stained to localise cytochrome c oxidase within the cells. Mitochondrial protein content and cytochrome c oxidase enzymatic activity were determined. Expression of cytochrome c oxidase subunits, COXI and COXIV, was assessed by qRT-PCR. RESULTS Cytochrome c oxidase staining remained minimal in chondrocytes cultured in alginate for 4 weeks under 21% oxygen. Mitochondrial protein content and cytochrome c oxidase activity increased significantly during 9 days of chondrocyte expansion in monolayer, accompanied by up-regulation of the COXI mitochondrial gene but not the COXIV nuclear-encoded gene. Cytochrome c oxidase staining increased from day 5 of monolayer culture and remained high even after the cells were returned to 3-D culture for 4 weeks. CONCLUSIONS Culture of chondrocytes in monolayer leads to a rapid increase in mitochondrial protein content and cytochrome c oxidase activity. The increase in cytochrome c oxidase activity is not reversed even after chondrocytes are returned to 3-D culture for 4 weeks; high oxygen tension alone does not appear to stimulate cytochrome c oxidase activity.
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Affiliation(s)
- O A Boubriak
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, UK.
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