Gene expression profiles of dynamically compressed single chondrocytes and chondrons

School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, UK
Biochemical and Biophysical Research Communications (Impact Factor: 2.3). 02/2009; 379(3):738-742. DOI: 10.1016/j.bbrc.2008.12.111


A chondrocyte produces a hydrated pericellular matrix (PCM); together they form a chondron. Previous work has shown that the presence of the PCM influences the biological response of chondrocytes to loading. The objective of this study was to determine the gene expression profiles of enzymatically isolated single chondrocytes and chondrons in response to dynamic compression. Cartilage specific extracellular matrix components and transcription factors were examined. Following dynamic compression, chondrocytes and chondrons showed variations in gene expression profiles. Aggrecan, Type II collagen and osteopontin gene expression were significantly increased in chondrons. Lubricin gene expression decreased in both chondrons and chondrocytes. Dynamic compression had no effect on SOX9 gene expression. Our results demonstrate a clear role for the PCM in interfacing the mechanical signalling in chondrocytes in response to dynamic compression. Further investigation of single chondrocytes and chondrons from different zones within articular cartilage may further our understanding of cartilage mechanobiology.

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Available from: Nicola J Kuiper, Sep 11, 2015
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    • "The effects of mechanical stimuli on adult cartilage have been widely investigated and found to be important in maintenance of the tissue. Single cell approaches have been used to study the role of mechanical forces on isolated single chondrocytes with and without their pericellular chondron and with chitosan encapsulation (Nguyen et al., 2009; Wang et al., 2009). Given that tissue engineering approaches aim to develop functional constructs from stem or progenitor cell populations, it follows that elucidation of the effects of loading during embryogenesis may provide useful insights into the loading strategies required to generate functional cartilage under laboratory conditions. "
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    • "Cell–matrix interactions also play a key role in regulating stem cell fate. Integrin mediated adhesion to the extracellular matrix has been shown to modulate both chondrogenic (Connelly et al., 2008) and osteogenic (Kundu et al., 2009) MSC differentiation, and may act as a means for mechanotransduction (Kock et al., 2009; Wang et al., 2009). One such natural hydrogel which facilitates integrin binding to ligands present on the scaffold is fibrin (Janmey et al., 2009). "
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