Inhibition of lens epithelial cell proliferation by substituted PMMA intraocular lenses

Background: Migration and proliferation of lens epithelial cells (LECs) are based on interactions between cellular integrins and extracellular matrix proteins (ECMs). We were able to design polymers substituted with COO- and SO3- groups that counteract LEC proliferation through modification of the i ntegrin/ECM interaction. The objective of this study was to compare the cel l proliferation-inhibiting properties of differently substituted copolymers with those of a homopolymer. Methods: Polymers were synthesized by radical polymerization and characterized by nuclear resonance spectroscopy. Second -passage rabbit LECs were cultured either on PMMA homopolymers (control) or on substituted PMMA copolymers, Cells were counted on days 2, 7, and 7, Ce ll vitality was evaluated by trypan blue staining. Experiments were run in quadruplicate. Statistical analysis was performed using the Wilcoxon test a nd the Mann-WhitneyU-test, Results: Compared with control, cells cultured o n copolymers grew to significantly lower cell numbers. The inhibitory effec t became evident at day 2 after seeding and persisted throughout the experi ment. Different ratios of COO-/SO3- substitutions yielded different grades of inhibition. No toxic effect was seen on rabbit LECs. Conclusions: The te st ed copolymers inhibit cell proliferation and are nontoxic. Further evalu ation could lead to the development of new intraocular lens materials that prevent secondary cataract.