Figure 5. Effect of XT-I overexpression on GAG anabolism in chondrocytes and cartilage.

(A) Immunoblot of XT-I protein in pCMV- or pCMV-XT-I-transfected chondrocytes 48 h after transfection. XT-I recombinant protein was indicated by the arrow. (B) GAG synthesis in primary human chondrocytes or (C) in cartilage explants from late OA region of human femoral condyle transfected with pCMV- (control) or pCMV-XT-I vector. XT-I- or mock-transfected cells or cartilage were labeled with ³⁵S-sulfate, and the amount of ³⁵S-labeled GAGs was measured 48 h posttransfection. Data are mean ± SD of 3 experiments per parameter, per joint, per patient. **,*Significantly (P<0.01, P<0.05, respectively) higher than controls.