Purpose: To evaluate lens epithelial cell (LEC) adhesion on different intraocular lens (IOL) materials with particular attention to the distribution of proteins located in the focal contacts.
Setting: Center of Biotechnological and Clinical Research in Ophthalmology, University of Bologna, Italy.
Methods: The IOL materials tested were poly(methyl methacrylate) (PMMA), heparin-surface-modified PMMA (HSM PMMA), polyHEMA, and silicone. Primary cultures of human LECs were established from human anterior capsules obtained during cataract surgery. The mean number of cells attached per square millimeter was calculated for each material after 24 and 72 hours. Transmission electron microscopy and immunocytochemical analysis were performed to detect the proteins actin, vinculin, and talin.
Results: Mean adhesiveness of human LECs increased over time with PMMA and decreased with the other materials. At 72 hours, mean LECs ranged from 54.8 cells/mm2 +/- 12.8 (SD) on PMMA to 2.1 +/- 0.7 cells/mm2 on silicone. The means for HSM PMMA and polyHEMA fell in between. The cytoskeletal proteins were arranged to produce focal contacts in only the LECs cultured on PMMA. The LECs cultured on polyHEMA, HSM PMMA, and silicone attached but failed to develop focal contacts or stress fibers.
Conclusion: This study confirms the multifactorial pathogenesis of posterior capsule opacification and suggests its incidence will be reduced by improving surgical techniques and using IOL surfaces that discourage cell adhesion.