Fig. 4.

Inhibition of the spatial reorganization of retinal neurons and RPE cells by the metalloproteinase inhibitor TIMP-1. (A,B) Phase and (C,D) fluorescence photomicrographs of neuroepithelial cocultures without (A,C) or with (B,D) TIMP-1 (150 ng/mL), added immediately after seeding RPE cells over a 1-day neuronal culture (open arrows). After 24 hr, the cocultures were fixed and labeled with phalloidin (C,D). In the absence of TIMP-1, RPE cells promoted the spatial rearrangement of neuronal cells (open arrows in A,C), which ended on top of RPE cells. Phalloidin staining showed the occurrence of neurites on top of RPE cells in TIMP-lacking cultures (white arrows in C). In cultures treated with TIMP-1, neuronal cell bodies (open arrow in B) and their neurites (thin arrows in B, D) remained attached to the dish surface. Scale bar = 10 µm.