Transforming growth factor-β2 levels in aqueous humor of glaucomatous eyes

Purpose: To determine whether clinical characteristics are correlated with increased levels of transforming growth factor-beta (2) (TGF-beta (2)) in aqueous humor in glaucomatous eyes. Methods: Aqueous humor samples were collected from 91 glaucomatous eyes. Included were samples from primary open-angle glaucoma (POAG) in 40 eyes, (pseudo)exfoliation syndrome (EXS) in 18 eyes, primary angle-closure glaucoma (PACG) in 26 eyes and uveitis-related secondary glaucoma (SG) in 7 eyes. TGF-beta (2) in aqueous humor was assessed with a specific-capture ELISA. Results: The mean concentration (+/- standard error) of mature (biologically active) TGF-beta (2) in the aqueous humor of eyes with POAG was 293.6 +/- 33.6 pg/ml, significantly higher than that in eyes with PACG, EXS and SG: 147.5 +/- 28.1, 135.8 +/- 30.2 and 41.0 +/- 10.7 pg/ml, respectively (P=0.0006, P=0.0010 and P=0.0003; analysis of variance). The mean concentration (rt standard error) Of total TGF-beta (2) in the aqueous humor of eyes with POAG was 1647.6 +/- 124.5 pg/ml, not significantly different from that in eyes with PACG, EXS and SG: 1482.9 +/- 148.2, 1442.7 +/- 187.8 and 1929.0 +/- 367.6 pg/ml, respectively. A multivariate analysis using logistic regression showed significant correlations between mature TGF-beta (2) concentration and history of cataract surgery (P=0.0225) and the use of carbonic anhydrase inhibitors (P=0.0133). Conclusions: Our results indicate that increased levels of TGF-beta (2) may play an important role in the pathogenesis of POAG.