Figure 3
Lung development is highly abnormal in transgenic embryos. Hematoxylin and Eosin staining. A: Wildtype E18.5 lung lobe. B: Transgenic E18.5 lung lobe. Transgenic embryos exhibited highly abnormal lung development with disruption of branching morhogenesis leading to formation of empty lumens and dense tissue in place of alveolar sacks. The alveolar epithelium appeared undifferentiated without the typical flattening usually seen at this stage. Proximal bronchi development had occurred to some degree, but distal bronchioles were absent. C: One of two embryos that expressed Fgf10FLAG in a single lobe only. Surrounding lobes expressed no transgene and appeared normal, thus providing and excellent comparison for the transgenic phenotype. D: Magnification from A. E: Magnification from B. The lung lobe shown in C and the transgenic lung represented in B are shown throughout the paper, as they were representative for the phenotypes.