Fig. 7.

Active migration of photoreceptor cell bodies. Photomicrographs of RPE cells seeded over neuronal cells, taken at 0 hr (A), 1 hr (B), and 2 hr (C) after seeding RPE cells on top of retinal neurons. A photoreceptor cell body (A–C, black solid arrows) is visible rapidly moving along its own neurite, migrating parallel to RPE cells, while other photoreceptors (white arrows) were left behind. Photomicrographs after 2 hr (D) and 3 hr (E) of seeding RPE cells on top of neuronal cells show that RPE lamellipodia (white arrowheads) reached the neuronal processes (black empty arrows, D) and extended beneath neurons (E). Some neurons (black thin arrows in D,E) initially extended their neurites (empty arrows in D,E) toward the RPE cells, but then changed their orientation by displacing their cell bodies toward the epithelium (black thin arrow in E). Scale bars = 10 µm.