Figure 3.

IGFBP‐4 expression is reduced in SSc lung fibroblasts and IGFBP‐4 decreases ECM and α‐SMA levels in SSc lung tissues in organ culture. (A) IGFBP‐4 expression is reduced in SSc fibroblasts. IGFBP‐4 mRNA was measured by real‐time PCR in primary pulmonary fibroblasts from nine patients with SSc and nine normal donors. All fibroblasts were in passage 3. Levels were normalized to GAPDH. (B) IGFBP‐4 reduces SSc lung collagen mRNA levels in ex vivo lung culture. Human SSc lung tissue cores were infected with adenovirus encoding IGFBP‐4 or control virus for 4 days. Collagen mRNA levels were measured by real‐time PCR. The graph shows results from eight different human SSc lung donors. (C) IGFBP‐4 reduces ECM production and levels of the myofibroblast marker α‐SMA. Human SSc lung tissues in ex vivo culture were infected with adenovirus encoding IGFBP‐4 or control virus for 7 days. Lung tissues were harvested and homogenized. An equal amount of total protein was analyzed by WB for collagen, fibronectin, and α‐SMA. GAPDH was used to confirm equal loading of protein. D. Graphical presentation of densitometry results from three different human SSc donor lung tissues. *P < 0.05