Open AccessIdentification of markers to characterize and sort human articular chondrocytes with enhanced in vitro chondrogenic capacity
Author(s) -
Grogan Shawn Patrick,
Barbero Andrea,
DiazRomero Jose,
CletonJansen AnneMarie,
Soeder Stephan,
Whiteside Robert,
Hogendoorn Pancras C. W.,
Farhadi Jian,
Aigner Thomas,
Martin Ivan,
MainilVarlet Pierre
Publication year - 2007
Publication title -
arthritis & rheumatism
Language(s) - English
Resource type - Journals
eISSN - 1529-0131
pISSN - 0004-3591
DOI - 10.1002/art.22408
Subject(s) - chondrogenesis , cd44 , flow cytometry , chondrocyte , microbiology and biotechnology , aggrecanase , aggrecan , cartilage , cell sorting , chemistry , type ii collagen , glycosaminoglycan , biology , in vitro , mesenchymal stem cell , biochemistry , anatomy , pathology , medicine , osteoarthritis , articular cartilage , alternative medicine
Objective To identify markers associated with the chondrogenic capacity of expanded human articular chondrocytes and to use these markers for sorting of more highly chondrogenic subpopulations. Methods The chondrogenic capacity of chondrocyte populations derived from different donors (n = 21) or different clonal strains from the same cartilage biopsy specimen (n = 21) was defined based on the glycosaminoglycan (GAG) content of tissues generated using a pellet culture model. Selected cell populations were analyzed by microarray and flow cytometry. In some experiments, cells were sorted using antibodies against molecules found to be associated with differential chondrogenic capacity and again assessed in pellet cultures. Results Significance Analysis of Microarrays indicated that chondrocytes with low chondrogenic capacity expressed higher levels of insulin‐like growth factor 1 and of catabolic genes (e.g., matrix metalloproteinase 2, aggrecanase 2), while chondrocytes with high chondrogenic capacity expressed higher levels of genes involved in cell–cell or cell–matrix interactions (e.g., CD49c, CD49f). Flow cytometry analysis showed that CD44, CD151, and CD49c were expressed at significantly higher levels in chondrocytes with higher chondrogenic capacity. Flow cytometry analysis of clonal chondrocyte strains indicated that CD44 and CD151 could also identify more chondrogenic clones. Chondrocytes sorted for brighter CD49c or CD44 signal expression produced tissues with higher levels of GAG per DNA (up to 1.4‐fold) and type II collagen messenger RNA (up to 3.4‐fold) than did unsorted cells. Conclusion We identified markers that allow characterization of the capacity of monolayer‐expanded chondrocytes to form in vitro cartilaginous tissue and enable enrichment for subpopulations with higher chondrogenic capacity. These markers might be used as a means to predict and possibly improve the outcome of cell‐based cartilage repair techniques.