Figure 2.

IGFBP‐4 decreases ECM production levels ex vivo in human lung and skin organ culture. (A) IGFBP‐4 decreases baseline and TGF‐ß– induced collagen mRNA levels in human lung. Normal human donor lung tissues were cultured with 2 µg/mL of rhIGFBP‐4 with or without 10 ng/mL TGF‐ß1 for 4 days. Collagen mRNA expression was analyzed by real‐time PCR. The graph shows results from lung tissues of three different donors. (B) IGFBP‐4 decreases baseline and TGF‐ß–induced collagen levels in human lung. Donor lungs were cultured as in A, except that the culture time was extended to 7 days. Lung tissues were homogenized and equal amounts of total protein analyzed by WB. The graph shows results from lung tissues of three different donors. (C) IGFBP‐4 decreases TGF‐ß–induced hydroxyproline levels in human skin. Human newborn foreskin was maintained in organ culture in the presence of 2 µg/mL rhIGFBP‐4 with or without 10 ng/mL TGF‐ß1 for 7 days. Collagen content was measured using a hydroxyproline assay. The graph includes results from the skin of four different donors. *P < 0.05, **P < 0.01