Figure 3.

Blocking the Fas ligand-Fas-caspase pathway interferes with palatal fusion in organ culture. H&E staining after organ culture of E13.5 palatal shelves from wild-type mice treated with BSA (A), blocking Fas-L antibody (B, C), or pan-caspase-inhibitor z-VAD (D) for 4 days. All of the samples treated with BSA fused together completely (A), whereas samples treated with Fas ligand antibody fused partially (B) or not at all (C), and all samples treated with z-VAD failed to fuse (D). Scale bars: A-D, 50 µm.