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Kroupa KR, Gangi LR, Zimmerman BK, Hung CT, Ateshian GA. Superficial zone chondrocytes can get compacted under physiological loading: A multiscale finite element analysis. Acta Biomater 2023; 163:248-258. [PMID: 36243365 PMCID: PMC10324087 DOI: 10.1016/j.actbio.2022.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 09/27/2022] [Accepted: 10/05/2022] [Indexed: 11/01/2022]
Abstract
Recent in vivo and in vitro studies have demonstrated that superficial zone (SZ) chondrocytes within articular layers of diarthrodial joints die under normal physiologic loading conditions. In order to further explore the implications of this observation in future investigations, we first needed to understand the mechanical environment of SZ chondrocytes that might cause them to die under physiological sliding contact conditions. In this study we performed a multiscale finite element analysis of articular contact to track the temporal evolution of a SZ chondrocyte's interstitial fluid pressure, hydraulic permeability, and volume under physiologic loading conditions. The effect of the pericellular matrix modulus and permeability was parametrically investigated. Results showed that SZ chondrocytes can lose ninety percent of their intracellular fluid after several hours of intermittent or continuous contact loading, resulting in a reduction of intracellular hydraulic permeability by more than three orders of magnitude. These findings are consistent with loss of cell viability due to the impediment of cellular metabolic pathways induced by the loss of fluid. They suggest that there is a simple mechanical explanation for the vulnerability of SZ chondrocytes to sustained physiological loading conditions. Future studies will focus on validating these specific findings experimentally. STATEMENT OF SIGNIFICANCE: As with any mechanical system, normal 'wear and tear' of cartilage tissue lining joints is expected. Yet incidences of osteoarthritis are uncommon in individuals younger than 45. This counter-intuitive observation suggests there must be an intrinsic repair mechanism compensating for this wear and tear over many decades of life. Recent experimental studies have shown superficial zone chondrocytes die under physiologic loading conditions, suggesting that this repair mechanism may involve cell replenishment. To better understand the mechanical environment of these cells, we performed a multiscale computational analysis of articular contact under loading. Results indicated that normal activities like walking or standing can induce significant loss of intracellular fluid volume, potentially hindering metabolic activity and fluid transport properties, and causing cell death.
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Affiliation(s)
- Kimberly R Kroupa
- Department of Mechanical Engineering, Columbia University, 500 West 120th Street, 220 S.W. Mudd, New York, NY 10027, USA
| | - Lianna R Gangi
- Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace, 1210 Amsterdam Avenue, New York, NY 10027, USA
| | - Brandon K Zimmerman
- Department of Mechanical Engineering, Columbia University, 500 West 120th Street, 220 S.W. Mudd, New York, NY 10027, USA
| | - Clark T Hung
- Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace, 1210 Amsterdam Avenue, New York, NY 10027, USA; Department of Orthopedic Surgery, Columbia University, 622 West 168th Street PH 11 - Center, New York, NY 10032, USA
| | - Gerard A Ateshian
- Department of Mechanical Engineering, Columbia University, 500 West 120th Street, 220 S.W. Mudd, New York, NY 10027, USA; Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace, 1210 Amsterdam Avenue, New York, NY 10027, USA.
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Zonal-Layered Chondrocyte Sheets for Repairment of Full-Thickness Articular Cartilage Defect: A Mini-Pig Model. Biomedicines 2021; 9:biomedicines9121806. [PMID: 34944622 PMCID: PMC8698967 DOI: 10.3390/biomedicines9121806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/19/2021] [Accepted: 11/26/2021] [Indexed: 11/16/2022] Open
Abstract
The cell sheet technique is a promising approach for tissue engineering, and the present study is aimed to determine a better configuration of cell sheets for cartilage repair. For stratified chondrocyte sheets (S-CS), articular chondrocytes isolated from superficial, middle, and deep zones were stacked accordingly. Heterogeneous chondrocyte sheets (H-CS) were obtained by mixing zonal chondrocytes. The expressions of chondrocytes, cytokine markers, and glycosaminoglycan (GAG) production were assessed in an in vitro assay. The curative effect was investigated in an in vivo porcine osteochondral defect model. The S-CS showed a higher cell viability, proliferation rate, expression of chondrogenic markers, secretion of tissue inhibitor of metalloproteinase, and GAG production level than the H-CS group. The expressions of ECM destruction enzyme and proinflammatory cytokines were lower in the S-CS group. In the mini-pigs articular cartilage defect model, the S-CS group had a higher International Cartilage Repair Society (ICRS) macroscopic score and displayed a zonal structure that more closely resembled the native cartilage than those implanted with the H-CS. Our study demonstrated that the application of the S-CS increased the hyaline cartilage formation and improved the surgical outcome of chondrocyte implication, offering a better tissue engineering strategy for treating articular cartilage defects.
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Brown WE, Huey DJ, Hu JC, Athanasiou KA. Functional self-assembled neocartilage as part of a biphasic osteochondral construct. PLoS One 2018; 13:e0195261. [PMID: 29634740 PMCID: PMC5892872 DOI: 10.1371/journal.pone.0195261] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/19/2018] [Indexed: 11/29/2022] Open
Abstract
Bone-to-bone integration can be obtained by osteoconductive ceramics such as hydroxyapatite (HAp) and beta-tricalcium phosphate (β-TCP), but cartilage-to-cartilage integration is notoriously difficult. Many cartilage repair therapies, including microfracture and mosaicplasty, capitalize on the reparative aspects of subchondral bone due to its resident population of stem cells and vascularity. A strategy of incorporating tissue engineered neocartilage into a ceramic to form an osteochondral construct may serve as a suitable alternative to achieve cartilage graft fixation. The use of a tissue engineered osteochondral construct to repair cartilage defects may also benefit from the ceramic’s proximity to underlying bone and abundant supply of progenitor cells and nutrients. The objective of the first study was to compare HAp and β-TCP ceramics, two widely used ceramics in bone regeneration, in terms of their ability to influence neocartilage interdigitation at an engineered osteochondral interface. Additional assays quantified ceramic pore size, porosity, and compressive strength. The compressive strength of HAp was six times higher than that of β-TCP due to differences in porosity and pore size, and HAp was thus carried forward in the second study as the composition with which to engineer an osteochondral construct. Importantly, it was shown that incorporation of the HAp ceramic in conjunction with the self-assembling process resulted in functionally viable neocartilage. For example, only collagen/dry weight and ultimate tensile strength of the chondral control constructs remained significantly greater than the neocartilage cut off the osteochondral constructs. By demonstrating that the functional properties of engineered neocartilage are not negatively affected by the inclusion of an HAp ceramic in culture, neocartilage engineering strategies may be directly applied to the formation of an osteochondral construct.
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Affiliation(s)
- Wendy E Brown
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, United States of America
| | - Daniel J Huey
- Department of Biomedical Engineering, University of California Davis, Davis, California, United States of America
| | - Jerry C Hu
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, United States of America
| | - Kyriacos A Athanasiou
- Department of Biomedical Engineering, University of California Irvine, Irvine, California, United States of America
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Schuurman W, Harimulyo EB, Gawlitta D, Woodfield TBF, Dhert WJA, van Weeren PR, Malda J. Three-dimensional assembly of tissue-engineered cartilage constructs results in cartilaginous tissue formation without retainment of zonal characteristics. J Tissue Eng Regen Med 2013; 10:315-24. [DOI: 10.1002/term.1726] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2012] [Revised: 08/08/2012] [Accepted: 01/22/2013] [Indexed: 01/15/2023]
Affiliation(s)
- W. Schuurman
- Department of Orthopaedics; University Medical Centre Utrecht; The Netherlands
- Department of Equine Sciences, Faculty of Veterinary Sciences; Utrecht University; The Netherlands
| | - E. B. Harimulyo
- Department of Orthopaedics; University Medical Centre Utrecht; The Netherlands
| | - D. Gawlitta
- Department of Orthopaedics; University Medical Centre Utrecht; The Netherlands
| | - T. B. F. Woodfield
- Department of Orthopaedic Surgery; University of Otago; Christchurch New Zealand
| | - W. J. A. Dhert
- Department of Orthopaedics; University Medical Centre Utrecht; The Netherlands
- Faculty of Veterinary Sciences; University of Utrecht; The Netherlands
| | - P. R. van Weeren
- Department of Equine Sciences, Faculty of Veterinary Sciences; Utrecht University; The Netherlands
| | - J. Malda
- Department of Orthopaedics; University Medical Centre Utrecht; The Netherlands
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Coates EE, Fisher JP. Phenotypic variations in chondrocyte subpopulations and their response to in vitro culture and external stimuli. Ann Biomed Eng 2010; 38:3371-88. [PMID: 20556515 DOI: 10.1007/s10439-010-0096-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Accepted: 06/04/2010] [Indexed: 12/24/2022]
Abstract
Articular cartilage defects have limited capacity to self-repair, and cost society up to 60 billion dollars annually in both medical treatments and loss of working days. Recent developments in cartilage tissue engineering have resulted in many new products coming to market or entering clinical trials. However, there is a distinct lack of treatments which aim to recreate the complex zonal organization of articular cartilage. Cartilage tissue withstands repetitive strains throughout an individual's lifetime and provides frictionless movement between joints. The structure and composition of its intricately organized extracellular matrix varies with tissue depth to provide optimal resistance to loading, ensure ease of movement, and integrate with the subchondral bone. Each tissue zone is specially designed to resist the load it experiences, and maximize the tissue properties needed for its location. It is unlikely that a homogenous solution to tissue repair will be able to optimally restore the function of such a heterogeneous tissue. For zonal engineering of articular cartilage to become practical, maintenance of phenotypically stable zonal cell populations must be achieved. The chondrocyte phenotype varies considerably by zone, and it is the activity of these cells that help achieve the structural organization of the tissue. This review provides an examination of literature which has studied variations in cellular phenotype between cartilage zones. By doing so, we have identified critical differences between cell populations and highlighted areas of research which show potential in the field. Current research has made the morphological and metabolic variations between these cell populations clear, but an ideal way of maintaining these differences in vitro culture is yet to be established. Combinations of delivered growth factors, mechanical loading, and layered three-dimensional culture systems all show potential for achieving this goal. Furthermore, differentiation of progenitor cell populations into chondrocyte subpopulations may also hold promise for achieving large numbers of zonal chondrocytes. Success of the field lies in establishing methods of retaining phenotypically stable cell populations for in vitro culture.
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Affiliation(s)
- Emily E Coates
- Fischell Department of Bioengineering, University of Maryland, 3238 Jeong H. Kim Engineering Building, College Park, MD 20742, USA
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A comparison of primary and passaged chondrocytes for use in engineering the temporomandibular joint. Arch Oral Biol 2008; 54:138-45. [PMID: 19013549 DOI: 10.1016/j.archoralbio.2008.09.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2008] [Revised: 09/09/2008] [Accepted: 09/24/2008] [Indexed: 11/21/2022]
Abstract
OBJECTIVE This study examines the tissue engineering potential of passaged (P3) and primary (P0) articular chondrocytes (ACs) and costal chondrocytes (CCs) from skeletally mature goats for use in the temporomandibular joint (TMJ). DESIGN These four cell types were assembled into scaffoldless tissue engineered constructs and cultured for 4 wks. The constructs were then tested for cell, collagen, and glycosaminoglycan (GAG) content with biochemical assays, and collagen types I and II with enzyme-linked immunosorbent assays. Constructs were also tested under tension and compression to determine biomechanical properties. RESULTS Both primary and passaged CC constructs had greater GAG/wet weight than AC constructs. Primary AC constructs had significantly less total collagen and contained no collagen type I. AC P3 constructs had the largest collagen I/collagen II ratio, which was also greater in passaged CC constructs relative to primary groups. Primary AC constructs were not mechanically testable, whereas passaged AC and CC constructs had significantly greater tensile properties than primary CC constructs. CONCLUSIONS Primary CCs are considerably better than primary ACs and have potential use in tissue engineering when larger quantities of collagen type II are desired. The poor performance of the ACs, in this study, which contradicts the results seen with previous studies using immature bovine ACs, may thus be attributed to the animals' maturity. However, CC P3 cells appear particularly well suited for tissue engineering fibrocartilage of the TMJ due to the high quantity of collagen and GAG, and tensile and compressive mechanical properties.
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Han E, Bae WC, Hsieh-Bonassera ND, Wong VW, Schumacher BL, Görtz S, Masuda K, Bugbee WD, Sah RL. Shaped, stratified, scaffold-free grafts for articular cartilage defects. Clin Orthop Relat Res 2008; 466:1912-20. [PMID: 18506565 PMCID: PMC2584257 DOI: 10.1007/s11999-008-0291-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Accepted: 04/23/2008] [Indexed: 01/31/2023]
Abstract
One goal of treatment for large articular cartilage defects is to restore the anatomic contour of the joint with tissue having a structure similar to native cartilage. Shaped and stratified cartilaginous tissue may be fabricated into a suitable graft to achieve such restoration. We asked if scaffold-free cartilaginous constructs, anatomically shaped and targeting spherically-shaped hips, can be created using a molding technique and if biomimetic stratification of the shaped constructs can be achieved with appropriate superficial and middle/deep zone chondrocyte subpopulations. The shaped, scaffold-free constructs were formed from the alginate-released bovine calf chondrocytes with shaping on one (saucer), two (cup), or neither (disk) surfaces. The saucer and cup constructs had shapes distinguishable quantitatively (radius of curvature of 5.5 +/- 0.1 mm for saucer and 2.8 +/- 0.1 mm for cup) and had no adverse effects on the glycosaminoglycan and collagen contents and their distribution in the constructs as assessed by biochemical assays and histology, respectively. Biomimetic stratification of chondrocyte subpopulations in saucer- and cup-shaped constructs was confirmed and quantified using fluorescence microscopy and image analysis. This shaping method, combined with biomimetic stratification, has the potential to create anatomically contoured large cartilaginous constructs.
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Affiliation(s)
- EunHee Han
- Department of Bioengineering, University of California-San Diego, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093-0412 USA
| | - Won C. Bae
- Department of Radiology, University of California-San Diego, La Jolla, CA USA
| | - Nancy D. Hsieh-Bonassera
- Department of Mechanical and Aerospace Engineering, University of California-San Diego, La Jolla, CA USA
| | - Van W. Wong
- Department of Bioengineering, University of California-San Diego, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093-0412 USA
| | - Barbara L. Schumacher
- Department of Bioengineering, University of California-San Diego, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093-0412 USA
| | - Simon Görtz
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, CA USA
| | - Koichi Masuda
- Department of Orthopedic Surgery and Biochemistry, Rush Medical College at Rush University Medical Center, Chicago, IL USA
| | - William D. Bugbee
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, CA USA
| | - Robert L. Sah
- Department of Bioengineering, University of California-San Diego, 9500 Gilman Drive, MC 0412, La Jolla, CA 92093-0412 USA ,Whitaker Institute of Biomedical Engineering, University of California-San Diego, La Jolla, CA USA
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Growth factor effects on costal chondrocytes for tissue engineering fibrocartilage. Cell Tissue Res 2008; 333:439-47. [PMID: 18597118 DOI: 10.1007/s00441-008-0652-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Accepted: 05/21/2008] [Indexed: 10/21/2022]
Abstract
Tissue-engineered fibrocartilage could become a feasible option for replacing tissues such as the knee meniscus or temporomandibular joint disc. This study employed five growth factors (insulin-like growth factor-I, transforming growth factor-beta1, epidermal growth factor, platelet-derived growth factor-BB, and basic fibroblast growth factor) in a scaffoldless approach with costal chondrocytes, attempting to improve biochemical and mechanical properties of engineered constructs. Samples were quantitatively assessed for total collagen, glycosaminoglycans, collagen type I, collagen type II, cells, compressive properties, and tensile properties at two time points. Most treated constructs had lower biomechanical and biochemical properties than the controls with no growth factors, suggesting a detrimental effect, but the treatment with insulin-like growth factor-I tended to improve the constructs. Additionally, the 6-week time point was consistently better than that at 3 weeks, with total collagen, glycosaminoglycans, and aggregate modulus doubling during this time. Further optimization of the time in culture and exogenous stimuli will be important in making a more functional replacement tissue.
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Hwang NS, Varghese S, Lee HJ, Theprungsirikul P, Canver A, Sharma B, Elisseeff J. Response of zonal chondrocytes to extracellular matrix-hydrogels. FEBS Lett 2007; 581:4172-8. [PMID: 17692846 PMCID: PMC2692751 DOI: 10.1016/j.febslet.2007.07.049] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2007] [Revised: 07/03/2007] [Accepted: 07/12/2007] [Indexed: 11/30/2022]
Abstract
We investigated the biological response of chondrocytes isolated from different zones of articular cartilage and their cellular behaviors in poly (ethylene glycol)-based (PEG) hydrogels containing exogenous type I collagen, hyaluronic acid (HA), or chondroitin sulfate (CS). The cellular morphology was strongly dependent on the extracellular matrix component of hydrogels. Additionally, the exogenous extracellular microenvironment affected matrix production and cartilage specific gene expression of chondrocytes from different zones. CS-based hydrogels showed the strongest response in terms of gene expression and matrix accumulation for both superficial and deep zone chondrocytes, but HA and type I collagen-based hydrogels demonstrated zonal-dependent cellular responses.
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Affiliation(s)
| | | | | | | | | | | | - Jennifer Elisseeff
- Address correspondence and reprint requests to Jennifer Elisseeff, PhD, Department of Biomedical Engineering, Johns Hopkins University, Clark Hall 106, 3400 North Charles Street, Baltimore, MD, 21218. Tel: 410-516-4015, Fax: 410-516-8152,
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Koay EJ, Hoben GMB, Athanasiou KA. Tissue engineering with chondrogenically differentiated human embryonic stem cells. Stem Cells 2007; 25:2183-90. [PMID: 17540854 DOI: 10.1634/stemcells.2007-0105] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This study describes the development and application of a novel strategy to tissue engineer musculoskeletal cartilages with human embryonic stem cells (hESCs). This work expands the presently limited understanding of how to chondrogenically differentiate hESCs through the use of chondrogenic medium alone (CM) or CM with two growth factor regimens: transforming growth factor (TGF)-beta3 followed by TGF-beta1 plus insulin-like growth factor (IGF)-I or TGF-beta3 followed by bone morphogenic protein (BMP)-2. It also extends the use of the resulting chondrogenically differentiated cells for cartilage tissue engineering through a scaffoldless approach called self-assembly, which was conducted in two modes: with (a) embryoid bodies (EBs) or (b) a suspension of cells enzymatically dissociated from the EBs. Cells from two of the differentiation conditions (CM alone and TGF-beta3 followed by BMP-2) produced fibrocartilage-like constructs with high collagen I content, low collagen II content, relatively high total collagen content (up to 24% by dry weight), low sulfated glycosaminoglycan content (approximately 4% by dry weight), and tensile properties on the order of megapascals. In contrast, hESCs treated with TGF-beta3 followed by TGF-beta1 + IGF-I produced constructs with no collagen I. Results demonstrated significant differences among the differentiation conditions in terms of other biochemical and biomechanical properties of the self-assembled constructs, suggesting that distinct growth factor regimens differentially modulate the potential of the cells to produce cartilage. Furthermore, this work shows that self-assembly of cells obtained by enzymatic dissociation of EBs is superior to self-assembly of EBs. Overall, the results of this study raise the possibility of manipulating the characteristics of hESC-generated tissue toward specific musculoskeletal cartilage applications.
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Affiliation(s)
- Eugene J Koay
- Rice University, Department of Bioengineering, Houston, Texas 77251-1892, USA
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Park K, Min BH, Han DK, Hasty K. Quantitative Analysis of Temporal and Spatial Variations of Chondrocyte Behavior in Engineered Cartilage during Long-Term Culture. Ann Biomed Eng 2006; 35:419-28. [PMID: 17151924 DOI: 10.1007/s10439-006-9219-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Accepted: 10/11/2006] [Indexed: 10/23/2022]
Abstract
In this work, we present the fact that chondrocyte activity differs in relation to their position in an engineered cartilage construct. Chondrocytes from porcine articular cartilage were cultured in a monolayer. Then the cell/extracellular matrix (ECM) membrane was peeled off and centrifuged into a three-dimensional (3D) pellet-type construct. Cultivated in a static condition, the constructs were harvested at specific time intervals (1, 2, 3, and 5 weeks) and manually cored using a biopsy punch to separate the core from the remaining construct. The resultant parts, core and peripheral remnant were thus obtained and subjected to analysis individually. Cell density (10(6 )cells/cm(3)) of the core was significantly higher at 1 week than that of the periphery but this trend was reversed at later time points. Cell viability was remarkably better in the peripheral tissue. Alcian blue staining of glycosaminoglycan (GAG) revealed an intense blue staining from the periphery, exhibiting a steep gradient in distribution of GAG concentration. The gene expression ratio of collagen type II to I appeared to be more altered in the periphery, possibly suggesting cell dedifferentiation, especially at later time points (>2 weeks). The mRNA levels of matrix metalloproteinase-1 (MMP-1) and MMP-13 remained in the normal range, whereas collagen type X expression was more significantly upregulated at the periphery. This study showed that chondrocyte behavior could be highly variable in the extent of their proliferation, differentiation and dedifferentiation, depending on their physical location within 3D engineered cartilage construct.
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Affiliation(s)
- Kwideok Park
- Biomaterials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, Korea.
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