Effect of TGF-(beta)2 and Anti-TGF(beta)2 antibody in a new in vivo rodent model of posterior capsule opacification

PURPOSE. This study evaluated the effect of transforming growth factor (TGF)-beta 2 and anti-TGF-beta 2 antibody in a rodent model of posterior capsule opacification (PCO).

METHODS. An extracapsular lens extraction (ECLE) was performed in 72 Sprague - Dawley rats. At the end of the procedure, 10 mu L TGF-beta 2 (TGF-beta 2-treated group), fetal calf serum (FCS)/phosphate-buffered saline (PBS; FCS/PBS-treated control group), a human monoclonal TGF-beta 2 antibody ( anti - TGF-beta 2 treated group), or a null control IgG4 antibody ( null antibody treated control group) was injected into the capsule. Animals were killed 3 and 14 days postoperatively. Eyes were evaluated clinically prior to euthanatization, then enucleated and processed for light microscopy and immunohistochemistry afterward. PCO was evaluated clinically and histopathologically. Student's t-test and chi(2) were used to assess differences between groups.

RESULTS. There were no statistically significant clinical or histopathological differences in degree of PCO between the TGF-beta 2 - and FCS/PBS-treated groups at 3 and 14 days after ECLE. Nor were there differences between the anti - TGF-beta 2 - and the null antibody - treated groups, with the exception of the histopathology score for capsule wrinkling 3 days after ECLE ( P = 0.02). alpha-Smooth-muscle actin staining was observed in the lens capsular bag only in areas where there was close contact with the iris.

CONCLUSIONS. No sustained effect of TGF-beta 2 or anti - TGF-beta 2 antibody on PCO was found in rodents at the dose and timing administered in this study. Iris cells may play a role in the process of epithelial mesenchymal transition linked to PCO.