Fig. 3. Morphological alterations of E6 chick retinae after neutralization of TGF-ß. Hematoxylin and Eosin-stained retinal cross sections of untreated (A,C) or anti-TGF-ß-treated (B,D) E6 chick embryos. The insets in A and B demarcate the region shown at higher magnification in C and D, respectively. Compared with control retinae, retinae of anti-TGF-ß-treated embryos are noticeably thicker and the retinal neuroepithelium exhibits protrusions and indentations (asterisks in B). le, lens; nr, neural retina; on, optic nerve; pe, pigment epithelium. Scale bars: 500 µm in A,B; 50 µm in C,D.