2004 Volume No 8 - pages 58-64
Title: Distinction between the extracellular matrix of
the nucleus pulposus and hyaline cartilage: a requisite for
tissue engineering of intervertebral disc |
Authors: F. Mwale, P. Roughley and J. Antoniou |
Address: Lady Davis Institute for Medical Research
and Department of Surgery, SMBD-Jewish General Hospital, Montreal
(QC) Canada |
E-mail: fmwale at ldi.jgh.mcgill.ca |
Key Words: Tissue engineering, intervertebral disc,
proteoglycan, collagen, glycosaminoglycan, nucleus pulposus,
annulus fibrosus, disc degeneration, hyaline cartilage. |
Publication date: December 15th 2004 |
Abstract: Tissue engineering of intervertebral discs
(IVD) using mesenchymal stem cells (MSCs) induced to differentiate
into a disc-cell phenotype has been considered as an alternative
treatment for disc degeneration. However, since there is no
unique marker characteristic of discs and since hyaline cartilage
and immature nucleus pulposus (NP) possess similar macromolecules
in their extracellular matrix, it is currently difficult to
recognize MSC conversion to a disc cell. This study was performed
to compare the proteoglycan to collagen ratio (measured as
GAG to hydroxyproline ratio) in the NP of normal disc to that
of the hyaline cartilage of the endplate within the same group
of individuals and test the hypothesis that this ratio can
be used for in vivo studies to distinguish between
a normal NP and hyaline cartilage phenotype. Whole human lumbar
spine specimens from fresh cadavers, ranging in age from 12
weeks to 79 years, were used to harvest the IVDs and adjacent
endplates. The GAG to hydroxyproline ratio within the NP of
young adults is approximately 27:1, whereas the ratio within
the hyaline cartilage endplate of the same aged individuals
is about 2:1. The production of an extracellular matrix with
a high proteoglycan to collagen ratio can be used in vivo
to distinguish NP cells from chondrocytes, and could help
in identifying a NP-like phenotype in vivo as opposed
to a chondrocyte when MSCs are induced to differentiate for
tissue engineering of a disc. |
Article download: Pages
58-64. (PDF file) |