This Article Full Text (OnlineFirst PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Scopus Google Scholar Articles by WONG, C.-C. Articles by TSAI, Y.-H. PubMed PubMed Citation Articles by WONG, C.-C. Articles by TSAI, Y.-H. Social Bookmarking                         What's this?

Phenotypic Re-expression of Near Quiescent Chondrocytes: The Effects of Type II Collagen and Growth Factors

¹ Department of Orthopaedic Surgery, WanFang Hospital, Taipei Medical University, Taipei, Taiwan
² Graduate Institute of Cell and Molecular Biology, Taipei Medical University, Taipei, Taiwan
³ Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan
⁴ Graduate Institute of Biomaterials, Taipei Medical University, Taipei, Taiwan
⁵ Department of Pathology, Taipei Medical University, Taipei, Taiwan
⁶ Department of Physical Medicine and Rehabilitation, Taipei Medical University Hospital, Taipei, Taiwan

^* To whom correspondence should be addressed. E-mail: csc{at}tmc.edu.tw.

	Abstract

After extensively expanding in monolayer culture, the cultured chondrocytes become quiescent. The aim of this study was to establish the hypothesis that the phenotypic function of extensively expanded primary chondrocytes may be restored with extracellular matrix (ECM) compositions with or without growth factors. The restoring effects of these microenvironmental factors on the near quiescent passage 9 (P9) chondrocyte were investigated. The data showed that exogenous type I collagen and type II collagen at 1 : 1 ratio stimulate cell proliferation greatly while type II collagen alone was enough to revive most of cartilaginous functions of near quiescent P9 chondrocytes. Exogenous type II collagen by itself was more effective in restoring cell proliferation rate, elevating glycosaminoglycan (GAG) accumulation and promoting the re-expression of type II collagen mRNAs in the near quiescent chondrocytes. The supplement of P9 chondrocytes with type II collagen plus TGF-1 and IGF-I appeared essential for the re-expression of aggrecan and type II collagen mRNA in monolayer culture. In 3D type II collagen construct, P9 chondrocytes appeared healthy as chondrocytes and showed clear lacuna. However, in 3D type I collagen matrix, only some P9 chondrocytes exhibited lacuna. The cartilaginous microenvironments are crucial to restoring chondrocyte-phenotypic features of the quiescent or ‘dedifferentiated’ chondrocytes, implicating the potential of expanding a scarcity of healthy chondrocytes for cartilage repair or regeneration.

First published on September 2, 2009
Journal of Biomaterials Applications 2009, doi:10.1177/0885328209343611


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?