Figure 2.

Co‐culture down‐regulates expression of specific genes in both osteoblasts and chondrocytes under physiological oxygen tension. (a) Aggrecan, COL II and SOX9 gene expression in chondrocytes and (b) ALP and RUNX2 gene expression in osteoblasts measured at different oxygen tensions and from different culture methods. GAPDH and β‐ACTIN were used as internal references. The product sizes are indicated in the left lane. The samples were collected at 1, 2, 3 and 5 days. The gels shown are representative of three different experiments (n = 3).