PLASMA SURFACE MODIFICATION OF ARTIFICIAL CORNEAS FOR OPTIMAL EPITHELIALIZATION

We have demonstrated that the optimal surface treatment of a polyvinyl alcoholcopolymer hydrogel for epithelial cell migration and proliferat ion is an argon radio frequency (rf) plasma treatment. The surface che mistry of the material was determined prior to each cellular evaluatio n, allowing us to compare the biological response with a known surface chemistry. The cellular response was carried out in a consistent mann er a minimum of three separate runs. We found that the optimal conditi ons required culturing the cells under constant rotation. Cells became confluent on argon-plasma-treated surfaces coated under several diffe rent reaction pressures, and after 2 weeks they became multilayered. O ur experiments demonstrated that cells proliferated and extracellular matrix and adhesion proteins were present only when the surface was tr eated with an argon rf plasma; acetone- and ammonia-treated surfaces d id not yield the desired results. Organ culture experiments further de monstrated the efficacy of the argon-treated surfaces. In these experi ments, intact keratoprosthetic devices with modified hydrogel surfaces were implanted into rabbit corneas. The excised corneas containing th e devices were cultured, and 3 weeks later, using confocal laser scann ing microscopy, confluent epithelium was detected on the modified hydr ogel surface. This is the first demonstration that rabbit limbal epith elial cells can migrate onto a synthetic cornea containing a modified hydrogel-treated surface and form a confluent surface of epithelium. ( C) 1997 John Wiley & Sons, Inc.