The surface of articular cartilage contains a progenitor cell population.
It is becoming increasingly apparent that articular cartilage growth is achieved by apposition from the articular surface. For such a mechanism to occur, a population of stem/progenitor cells must reside within the articular cartilage to provide transit amplifying progeny for growth. Here, we report on the isolation of an articular cartilage progenitor cell from the surface zone of articular cartilage using differential adhesion to fibronectin. This population of cells exhibits high affinity for fibronectin, possesses a high colony-forming efficiency and expresses the cell fate selector gene Notch 1. Inhibition of Notch signalling abolishes colony forming ability whilst activated Notch rescues this inhibition. The progenitor population also exhibits phenotypic plasticity in its differentiation pathway in an embryonic chick tracking system, such that chondroprogenitors can engraft into a variety of connective tissue types including bone, tendon and perimysium. The identification of a chondrocyte subpopulation with progenitor-like characteristics will allow for advances in our understanding of both cartilage growth and maintenance as well as provide novel solutions to articular cartilage repair.
Dowthwaite
Gary P
GP
Cardiff School of Biosciences and Cardiff Institute of Tissue Engineering and Repair, Cardiff University, PO Box 911, Museum Avenue, Cardiff CF10 3US, UK.
Bishop
Joanna C
JC
Redman
Samantha N
SN
Khan
Ilyas M
IM
Rooney
Paul
P
Evans
Darrell J R
DJ
Haughton
Laura
L
Bayram
Zubeyde
Z
Boyer
Sam
S
Thomson
Brian
B
Wolfe
Michael S
MS
Archer
Charles W
CW
D053829:Amyloid Precursor Protein Secretases; D000818:Animals; D001842:Bone and Bones / Q000196:embryology; D002358:Cartilage, Articular / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism*; D002417:Cattle; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002642:Chick Embryo; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism; D005353:Fibronectins / Q000494:pharmacology*; D005822:Genetic Vectors; D039081:Integrin alpha5beta1 / Q000378:metabolism; D011480:Protease Inhibitors / Q000494:pharmacology; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D013710:Tendons / Q000196:embryology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014161:Transduction, Genetic
D005353:Fibronectins; D039081:Integrin alpha5beta1; D011480:Protease Inhibitors; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; D014157:Transcription Factors; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases