Adhesion of fibronectin, vitronectin, laminin, and collagen type IV to intraocular lens materials in pseudophakic human autopsy eyes : Part 2: explanted intraocular lenses

Abstract

Purpose To evaluate fibronectin, vitronectin, laminin, and collagen type IV adhesion to poly(methyl methacrylate) (PMMA), silicone, hydrophobic soft acrylate, and hydrogel intraocular lenses (IOLs) in human pseudophakic autopsy eyes. Setting Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. Methods Thirty-two autopsy eyes containing PMMA, silicone, soft acrylate, or hydrogel IOLs were assessed. The IOLs were explanted from the capsular bag, and both sides of the IOLs were immunohistochemically stained for fibronectin, vitronectin, laminin, or collagen type IV. The number of cells on the IOL surfaces was counted. The capsular bag from 1 eye containing a soft acrylate IOL was examined for fibronectin and vitronectin. Results Hydrophobic soft acrylate IOLs had significantly more fibronectin adhering to their surfaces than PMMA ( P < .01) or silicone ( P < .01) IOLs, as well as more vitronectin. Silicone IOLs had more collagen type IV adhesion than the other IOLs ( P < .05–.06). Collective protein adhesion differed significantly between soft acrylate IOLs and PMMA and silicone IOLs, but not between PMMA and silicone IOLs. Conclusions The greater amount of protein on the hydrophobic soft acrylate (AcrySof®) IOLs seems to support an adhesive mechanism for their attachment to the capsular bag. Fibronectin and vitronectin have functional domains to bind them to lens epithelial cells and the collagenous capsule. This kind of attachment could be a true bioactive bond and may be 1 reason the PCO and neodymium:YAG capsulotomy rates are lower in eyes with a soft acrylate IOL.