Figure 3.

Effect of TGFβ inhibition on airway branch development in cultured E11 whole fetal lungs. (a) Images are high-power views of the left lung of representative ex vivo whole lungs in culture photographed at 24-hour intervals. The dashed lines outline airway branches. Over time in culture, lungs in all three conditions had progressive branching. However, at 48 and 72 hours the lungs treated with TGFβ inhibitory antibody had more developed airway arborization, and these branches appeared normal in size and shape compared to no antibody and control antibody treated lungs. (b) Terminal bud counts confirmed that airway branch numbers were significantly increased by TGFβ inhibitory antibody treatment after 24 and 72 hours of culture (**P = 0.02, *P = 0.03, TGFβ Ab versus control antibody and no Tx, mean ± SEM, N = 6–17 lungs). (c) The velocity of branching was significantly increased with TGFβ antibody treatment (*P = 0.01, TGFβ Ab versus control Ab and no Tx, mean ± SEM).