Effects of growth factors on cell proliferation and matrix synthesis of low-density, primary bovine chondrocytes cultured in collagen I gels

• Published in: Journal of orthopaedic research Vol. 20; no. 5; pp. 1070 - 1078
• Main Authors: Chaipinyo, Kanda, Oakes, Barry W, van Damme, Marie-Paule I
• Format: Journal Article
• Language: English
• Published: Hoboken Elsevier Ltd 01-09-2002; Wiley Subscription Services, Inc., A Wiley Company; Blackwell Publishing Ltd
• Subjects: Animals; Cattle; Cell Division - drug effects; Cell Survival - drug effects; Cells, Cultured; Chondrocytes - drug effects; Chondrocytes - metabolism; Chondrocytes - ultrastructure; Collagen - pharmacology; Extracellular Matrix - drug effects; Extracellular Matrix - metabolism; Extracellular Matrix - ultrastructure; Fibroblast Growth Factor 2 - pharmacology; Fluorescent Antibody Technique; Gels - pharmacology; Growth Substances - pharmacology; Insulin-Like Growth Factor I - pharmacology; Protein Biosynthesis; Proteoglycans - biosynthesis; Transforming Growth Factor beta - pharmacology
• ISSN: 0736-0266; 1554-527X
• DOI: 10.1016/S0736-0266(02)00025-6

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 (3.5×10
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-β1+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.