FIGURE 11.

BMP7 drives changes in variant CD44 gene expression, which are essential for mediating BMP7-driven alterations in myofibroblast phenotype. A, fibroblasts were grown to confluence before growth arrest in serum-free medium for 48 h. Cells were then treated under various cytokine conditions, as indicated, before extraction with TRIzol reagent. RNAs were purified, reverse-transcribed, and assessed for CD44v7/8 mRNA expression using RT-QPCR. B–D, cells were grown to subconfluence and transfected with specific siRNA nucleotides targeting CD44v7/8 for 24 h prior to the indicated cellular treatments. Cells were then treated under various cytokine conditions according to experimental models as described under “Experimental Procedures” before extraction with TRIzol reagent. RT-QPCR was used to assess CD44v7/8 (B), CD44s (C), and α-SMA (D) mRNA expression. Results are shown as the mean ± S.E. of three individual experiments. Statistical significance used the paired Student's t test, and p < 0.05 was considered as significant. E and F, cells were grown to subconfluence and transfected with specific siRNA nucleotides targeting CD44v7/8 24 h prior to the indicated cellular treatments. Cells were subsequently fixed and stained for HABP (E) and α-SMA (F) as shown. Original magnification ×400. Images shown are representative of three individual experiments.