1. Systematic assessment of growth factor treatment on biochemical and biomechanical properties of engineered articular cartilage constructs 
B.D. Elder, M.S., K.A. Athanasiou, Ph.D., P.E. 
Osteoarthritis and Cartilage 
Volume 17, Issue 1, Pages (January 2009)
DOI: /j.joca
Copyright © 2008 Osteoarthritis Research Society International Terms and Conditions

2. Fig. 1
Schematic diagram indicating experimental designs of phases I and II. The experimental design depicted in phase I was carried out for each individual growth factor separately (blocked by growth factor). The best treatment for each growth factor was selected for phase II. Phase II assessed the effects of each growth factor individually and in all combinations of two and three.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2008 Osteoarthritis Research Society International Terms and Conditions

3. Fig. 2
Photomicrographs of collagen and GAG staining for no growth factor control constructs, BMP-2+IGF-I treated constructs, and TGF-β1 treated constructs. 10× original magnification.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2008 Osteoarthritis Research Society International Terms and Conditions

4. Fig. 3
Biomechanical and biochemical properties of BMP-2 treated constructs in phase I. All BMP-2 treatments significantly increased (a) aggregate modulus with no effect on (b) Young's modulus. Likewise, all BMP-2 treatments significantly increased (c) GAG/WW with no effect on (d) collagen/WW. Columns and error bars represent means and standard deviations. Groups denoted by different letters are significantly different (P<0.05).
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2008 Osteoarthritis Research Society International Terms and Conditions

5. Fig. 4
Biomechanical and biochemical properties of IGF-I treated constructs in phase I. All IGF-I treatments, except 10 ng/ml continuous, significantly increased (a) aggregate modulus with no effect on (b) Young's modulus. Likewise, all IGF-I treatments, except 10ng/ml continuous, significantly increased (c) GAG/WW with no effect on (d) collagen/WW. Columns and error bars represent means and standard deviations. Groups denoted by different letters are significantly different (P<0.05).
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2008 Osteoarthritis Research Society International Terms and Conditions

6. Fig. 5
Biomechanical and biochemical properties of TGF-β1 treated constructs in phase I. TGF-β1 treatment at 30ng/ml and 2-wk continuous dosage significantly increased (a) aggregate modulus and (b) Young's modulus, with corresponding increases in (c) GAG/WW and (d) collagen/WW. Columns and error bars represent means and standard deviations. Groups denoted by different letters are significantly different (P<0.05).
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2008 Osteoarthritis Research Society International Terms and Conditions

7. Fig. 6
Biomechanical and biochemical properties of constructs in phase II. Combined treatment with BMP-2 and IGF-I led to the greatest enhancement of aggregate modulus and GAG/WW, while TGF-β1 alone was the only treatment to enhance both compressive and tensile stiffness. (a) Aggregate modulus, (b) Young's modulus, (c) GAG/WW and (d) collagen/WW. Columns and error bars represent means and standard deviations. Groups denoted by different letters are significantly different (P<0.05).
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2008 Osteoarthritis Research Society International Terms and Conditions