Fig. 9. Decreased expression of C/EBP in Titf1^–/– mice and Foxa2^/ mice. Lung sections from Titf1^+/–, Titf1^–/–, Foxa2^flx/flx and Foxa2^/ mice were prepared on E18.5 and immunostained for C/EBP. C/EBP was not altered in lungs from Titf1^+/– (A) and Foxa2^flx/flx (C) mice. Titf1^–/– mice (B) have a rudimentary bronchial tree associated with absent peripheral lung formation in which C/EBP staining was markedly decreased or absent. Expression of C/EBP was decreased in respiratory epithelial cells in the lungs of Foxa2^/ (deficient) mice (D). Scale bar: 25 µm.