title: Effects of growth factors on cell proliferation and matrix synthesis of low-density, primary bovine chondrocytes cultured in collagen I gels.
abstract: Low cell density cell numbers and dedifferentiation are two major problems of human chondrocyte culture associated with articular cartilage repair. Bovine chondrocytes seeded at low density (3.5 x 10(4) cells/ml of gels) in three-dimensional collagen type I gels do proliferate and maintain their phenotype as shown by cell counts, morphology and matrix synthesis. The combination of three growth factors (3GFs; 10 ng/ml TGF-beta1 + 100 ng/ml IGF-I + 10 ng/ml b-FGF) added to serum-free culture medium in this culture system enhances the mitotic activity of bovine chondrocytes similar to 20% foetal calf serum (FCS). At day 21, cells proliferated by 41 fold in gels-FCS and 37 fold in gels-3GFs. Protein synthesis by gels-3GFs cultures was similar to 20% FCS when cultured for 3 weeks but much less proteoglycan was synthesized. The matrix deposition as observed by light and electron microscopy was quite different. More small diameter branching collagen fibrils and a denser matrix were presented in gels-FCS culture whilst loosely arranged larger diameter collagen fibrils were observed in gels-3GFs.
authors.affiliation: kanda.chaipinyo@med.monash.edu.au
authors.forename: Kanda
authors.initials: K
authors.lastname: Chaipinyo
authors.forename: Barry W
authors.initials: BW
authors.lastname: Oakes
authors.forename: Marie-Paule I
authors.initials: MP
authors.lastname: van Damme
mesh_terms: D000818:Animals; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D003094:Collagen / Q000494:pharmacology; D005109:Extracellular Matrix / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D005782:Gels / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D014176:Protein Biosynthesis; D011509:Proteoglycans / Q000096:biosynthesis; D016212:Transforming Growth Factor beta / Q000494:pharmacology
chemical_list: D005782:Gels; D006133:Growth Substances; D011509:Proteoglycans; D016212:Transforming Growth Factor beta; D016222:Fibroblast Growth Factor 2; D007334:Insulin-Like Growth Factor I; D003094:Collagen