Objectives: The mandibular condylar cartilage is a heterogeneous tissue containing cells at various stages of chondrocyte maturation organized into 4 zones: superficial, polymorphic, flattened, and hypertrophic. The goal of this study was to use transgenic mice containing chondrocyte maturation markers fused to fluorescent protein transgenes to isolate and characterize homogenous cell populations of the mandibular condylar cartilage. Methods: Fluorescent reporter expression in the mandibular condylar cartilage of transgenic mice containing the 3.6-kb fragment of the rat collagen type 1 promoter fused to a topaz-fluorescent protein (Col3.6-tpz), collagen type 2 promoter fused to a cyan-fluorescent protein (Col2-cyan), and/or collagen type 10 promoter fused to cherry-fluorescent protein (Col10-cherry) was examined. Mandibular condylar cartilage cells were analyzed by fluorescence-activated cell sorting (FACS) and either used for gene expression analysis or plated in cell cultures and exposed to adipogenic, osteogenic, or chondrogenic conditions. To determine cell fate, transgenic mice containing the Col3.6-cre recombinase were bred with cre reporter mice. Results: Localization and analysis of gene expression revealed that Col3.6-tpz-positive cells corresponded to the polymorphic/flattened zones and Col2-cyan-positive cells corresponded to the flattened/hypertrophic zones of the mandibular condylar cartilage. Mandibular condylar cartilage FACS-sorted Col3.6-tpz-positive cells have the potential to differentiate into bone, cartilage, and fat. Cell fate mapping revealed that Col3.6 cells are precursors of some of the hypertrophic chondrocytes in the mandibular condylar cartilage. Conclusion: Col3.6-tpz cells represent an earlier stage of the mandibular condylar cartilage maturation pathway.

1.
Benjamin, M., J.R. Ralphs (2004) Biology of fibrocartilage cells. Int Rev Cytol 233: 1–45.
2.
Bi, W., J.M. Deng, Z. Zhang, R.R. Behringer, B. de Crombrugghe (1999) Sox9 is required for cartilage formation. Nat Genet 22: 85–89.
3.
Bilic-Curcic, I., M. Kronenberg, X. Jiang, J. Bellizzi, M. Mina, I. Marijanovic, E.M. Gardiner, D.W. Rowe (2005) Visualizing levels of osteoblast differentiation by a two-color promoter-GFP strategy: type I collagen-GFPcyan and osteocalcin-GFPtpz. Genesis 43: 87–98.
4.
Chokalingam, K., S. Hunter, C. Gooch, C. Frede, J. Florer, R. Wenstrup, D. Butler (2009) Three-dimensional in vitro effects of compression and time in culture on aggregate modulus and on gene expression and protein content of collagen type II in murine chondrocytes. Tissue Eng Part A 15: 2807–2816.
5.
Detamore, M.S., K.A. Athanasiou, J. Mao (2007) A call to action for bioengineers and dental professionals: directives for the future of TMJ bioengineering. Ann Biomed Eng 35: 1301–1311.
6.
Fukada, K., S. Shibata, S. Suzuki, K. Ohya, T. Kuroda (1999) In situ hybridisation study of type I, II, X collagens and aggrecan mRNAs in the developing condylar cartilage of fetal mouse mandible. J Anat 195: 321–329.
7.
Fukunaga, T., T. Yamashiro, S. Oya, N. Takeshita, M. Takigawa, T. Takano-Yamamoto (2003) Connective tissue growth factor mRNA expression pattern in cartilages is associated with their type I collagen expression. Bone 33: 911–918.
8.
Gerstenfeld, L.C., F.D. Shapiro (1996) Expression of bone-specific genes by hypertrophic chondrocytes: implication of the complex functions of the hypertrophic chondrocyte during endochondral bone development. J Cell Biochem 62: 1–9.
9.
Hinton, R.J., M. Serrano, S. So (2009) Differential gene expression in the perichondrium and cartilage of the neonatal mouse temporomandibular joint. Orthod Craniofac Res 12: 168–177.
10.
Hossain, K.S., N. Amizuka, N. Ikeda, K. Nozawa-Inoue, A. Suzuki, M. Li, K. Takeuchi, M. Aita, Y. Kawano, M. Hoshino, K. Oda, R. Takagi, T. Maeda (2005) Histochemical evidences on the chronological alterations of the hypertrophic zone of mandibular condylar cartilage. Microsc Res Tech 67: 325–335.
11.
Huang, W., U.I. Chung, H.M. Kronenberg, B. de Crombrugghe (2001) The chondrogenic transcription factor Sox9 is a target of signaling by the parathyroid hormone-related peptide in the growth plate of endochondral bones. Proc Natl Acad Sci USA 98: 160–165.
12.
Jiang, X., Z. Kalajzic, P. Maye, A. Braut, J. Bellizzi, M. Mina, D.W. Rowe (2005) Histological analysis of GFP expression in murine bone. J Histochem Cytochem 53: 593–602.
13.
Kalajzic, I., Z. Kalajzic, M. Kaliterna, G. Gronowicz, S.H. Clark, A.C. Lichtler, D. Rowe (2002) Use of type I collagen green fluorescent protein transgenes to identify subpopulations of cells at different stages of the osteoblast lineage. J Bone Miner Res 17: 15–25.
14.
Kalajzic, I., A. Staal, W.P. Yang, Y. Wu, S.E. Johnson, J.H. Feyen, W. Krueger, P. Maye, F. Yu, Y. Zhao, L. Kuo, R.R. Gupta, L.E. Achenie, H.W. Wang, D.G. Shin, D.W. Rowe (2005) Expression profile of osteoblast lineage at defined stages of differentiation. J Biol Chem 280: 24618–24626.
15.
Landesberg, R., E. Takeuchi, J.E. Puzas (1996) Cellular, biochemical and molecular characterization of the bovine temporomandibular joint disc. Arch Oral Biol 41: 761–767.
16.
Martel-Pelletier, J., C. Boileau, J.P. Pelletier, P.J. Roughley (2008) Cartilage in normal and osteoarthritis conditions. Best Pract Res Clin Rheumatol 22: 351–384.
17.
Meikle, M.C. (2007) Remodeling the dentofacial skeleton: the biological basis of orthodontics and dentofacial orthopedics. J Dent Res 86: 12–24.
18.
Naujoks, C., U. Meyer, H.P. Wiesmann, J. Jasche-Meyer, A. Hohoff, R. Depprich, J. Handschel (2008) Principles of cartilage tissue engineering in TMJ reconstruction. Head Face Med 4: 3.
19.
Ochiai, T., Y. Shibukawa, M. Nagayama, C. Mundy, T. Yasuda, T. Okabe, K. Shimono, M. Kanyama, H. Hasegawa, Y. Maeda, B. Lanske, M. Pacifici, E. Koyama (2010) Indian hedgehog roles in post-natal TMJ development and organization. J Dent Res 89: 349–354.
20.
Ohno, S., T. Schmid, Y. Tanne, T. Kamiya, K. Honda, M. Ohno-Nakahara, N. Swentko, T.A. Desai, K. Tanne, C.B. Knudson, W. Knudson (2006) Expression of superficial zone protein in mandibular condyle cartilage. Osteoarthritis Cartilage 14: 807–813.
21.
Rabie, A.B., G.H. Tang, H. Xiong, U. Hagg (2003) PTHrP regulates chondrocyte maturation in condylar cartilage. J Dent Res 82: 627–631.
22.
Rowe, D.W. (2005) Viewing problems in bone biology from the perspective of lineage identification. J Musculoskelet Neuronal Interact 5: 350–352.
23.
Rowe, D., A. Lichtler (2002) A strategy for identifying osteoporosis risk genes. Endocrine 17: 67–75.
24.
Schindeler, A., M.M. McDonald, P. Bokko, D.G. Little (2008) Bone remodeling during fracture repair: the cellular picture. Semin Cell Dev Biol 19: 459–466.
25.
Shibukawa, Y., B. Young, C. Wu, S. Yamada, F. Long, M. Pacifici, E. Koyama (2007) Temporomandibular joint formation and condyle growth require Indian hedgehog signaling. Dev Dyn 236: 426–434.
26.
Soriano, P. (1999) Generalized lacZ expression with the ROSA26 Cre reporter strain. Nat Genet 21: 70–71.
27.
Stewart, C.L., S.M. Standish (1983) Osteoarthritis of the TMJ in teenaged females: report of cases. J Am Dent Assoc 106: 638–640.
28.
Tanaka, E., M.S. Detamore, L.G. Mercuri (2008) Degenerative disorders of the temporomandibular joint: etiology, diagnosis, and treatment. J Dent Res 87: 296–307.
29.
Tsutsui, T.W., M. Riminucci, K. Holmbeck, P. Bianco, P.G. Robey (2008) Development of craniofacial structures in transgenic mice with constitutively active PTH/PTHrP receptor. Bone 42: 321–331.
30.
Viguet-Carrin, S., P. Garnero, P.D. Delmas (2006) The role of collagen in bone strength. Osteoporos Int 17: 319–336.
31.
Wadhwa, S., S. Kapila (2008) TMJ disorders: future innovations in diagnostics and therapeutics. J Dent Educ 72: 930–947.
32.
Wang, L., M. Lazebnik, M.S. Detamore (2009) Hyaline cartilage cells outperform mandibular condylar cartilage cells in a TMJ fibrocartilage tissue engineering application. Osteoarthritis Cartilage 17: 346–353.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.