Retinal pigment epithelial cell function on substrates with chemically micropatterned surfaces

Model substrates with desired chemical micropatterns were fabricated using a microcontact printing technique. The substrate surfaces contained organiz ed arrays of circular glass domains with a diameter of either 10 or 50 mu m surrounded and separated by regions modified with octadecyltrichlorosilane (OTS) self-assembled monolayers (SAMs). The effects of surface patterning on in vitro cell attachment, proliferation, morphology, and cytoskeletal or ganization were evaluated using a human retinal pigment epithelium (RPE) ce ll line. Both micropatterns affected initial RPE cell attachment, limited c ell spreading, and promoted the characteristic cuboidal cell morphology thr oughout the culture period. In contrast, RPE cells on plain glass control w ere elongated and appeared fibroblast-like prior to confluence. In addition , cells seeded at 30 000 cell/cm(2) on the patterned surfaces maintained a normal pattern of actin and cytokeratin expression, and formed confluent mo nolayers within 4 days of culture. The cell density increased about 30-fold on both micropatterns by day 7. These results show that it is feasible to control RPE cell shape and expression of differentiated phenotype using mic ropatterned surfaces. (C) 1999 Elsevier Science Ltd. All rights reserved.