The ontogeny of transferrin receptors in the embryonic chick retina: an immunohistochemical study

Transferrin receptor (TfR) immunoreactivity in the developing chick retina was examined. Immunoreactivity was detectable in the ganglion cells of embryonic day (E) 4 retina. At E9, diffuse TfR immunoreactivity appeared in the outer portion of the inner nuclear layer. Amacrine cells were the most intensely TfR-positive cells in the inner nuclear layer. At E11, the inner segment of photoreceptor cells showed moderate immunoreactivity. With the appearance of the outer segments, positive immunoreactivity was observed in these structures. TfR's developmental distribution in the retina may reflect the developmental and physiological role of transferrin.