Figure 8
Prolonged transforming growth factor (TGF)-β1 treatment induced a decrease in total Smad2 and/or Smad3 in many cell strains. Twenty-four human and mouse established cell lines and three primary human cell cultures were treated with TGF-β1 (5 ng/ml) for 48 hours. Extracts from control (-) and treated (+) cells were prepared and subjected to immunoblot analyses using antibodies for phosphorylated Smad2 (Ser 465/467), total Smad2, total Smad3, or actin.