title: Hyaline cartilage tissue is formed through the co-culture of passaged human chondrocytes and primary bovine chondrocytes.
abstract: To circumvent the problem of a sufficient number of cells for cartilage engineering, the authors previously developed a two-stage culture system to redifferentiate monolayer culture-expanded dedifferentiated human articular chondrocytes by co-culture with primary bovine chondrocytes (bP0). The aim of this study was to analyze the composition of the cartilage tissue formed in stage 1 and compare it with bP0 grown alone to determine the optimal length of the co-culture stage of the system. Biochemical data show that extracellular matrix accumulation was evident after 2 weeks of co-culture, which was 1 week behind the bP0 control culture. By 3 to 4 weeks, the amounts of accumulated proteoglycans and collagens were comparable. Expression of chondrogenic genes, Sox 9, aggrecan, and collagen type II, was also at similar levels by week 3 of culture. Immunohistochemical staining of both co-culture and control tissues showed accumulation of type II collagen, aggrecan, biglycan, decorin, and chondroitin sulfate in appropriate zonal distributions. These data indicate that co-cultured cells form cartilaginous tissue that starts to resemble that formed by bP0 after 3 weeks, suggesting that the optimal time to terminate the co-culture stage, isolate the now redifferentiated cells, and start stage 2 is just after 3 weeks.
authors.affiliation: CIHR-BioEngineering of Skeletal Tissues Team, Mount Sinai Hospital, Toronto, Canada.
authors.forename: Drew W
authors.initials: DW
authors.lastname: Taylor
authors.forename: Nazish
authors.initials: N
authors.lastname: Ahmed
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Hayes
authors.forename: Peter
authors.initials: P
authors.lastname: Ferguson
authors.forename: Allan E
authors.initials: AE
authors.lastname: Gross
authors.forename: Bruce
authors.initials: B
authors.lastname: Caterson
authors.forename: Rita A
authors.initials: RA
authors.lastname: Kandel
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D002417:Cattle; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism; D018920:Coculture Techniques; D003094:Collagen / Q000378:metabolism; D005260:Female; D006801:Humans; D011509:Proteoglycans / Q000378:metabolism; D013997:Time Factors; D023822:Tissue Engineering
chemical_list: D011509:Proteoglycans; D003094:Collagen