Abstract
Purpose: :
To compare aqueous humor levels of transforming growth factor (TGF)-β2 in non-glaucomatous eyes of African-American (Af-Am) and Caucasian (Cauc) subjects.
Methods: :
Patients undergoing cataract surgery aged >40 years without associated significant intraocular pathology (e.g., uveitis, glaucoma, etc.) were selected for this ongoing study. In bilateral cases, only the first operated study eye was included in this study. Aqueous humor was aspirated prior to any conjunctival or intraocular manipulation. A small amount of aqueous was withdrawn through an ab-externo corneal paracentesis site using a 27-G needle on a tuberculin syringe. All aqueous samples were stored at -80ºC until analyzed. The concentration of active TGF-β2 was measured by ELISA assay. All measurements were performed in duplicate by a masked observer.
Results: :
Twelve samples were analyzed (n=8 Af-Am; n=4 Cauc). Mean age was 68 years. Af-Am subjects were relatively younger with a mean age of 64 compared to 70 for Cauc. Age showed positive correlation with TGF-β2 (R2 = 0.43, 0.91 Af-Am and Cauc subjects, respectively; 0.59 for all subjects). Overall mean TGF-β2 concentration was 165.5 pg/mL. Average concentration of TGF-β2 was higher in Af-Am subjects compared to Cauc (250.6, 123.0 pg/mL, respectively).
Conclusions: :
Our results demonstrate a positive correlation between age and TGF-β2 in aqueous humor concentration. Despite overall positive correlation with age and younger age, Af-Am subjects tended to have higher TGF-β2 concentrations compared with Cauc subjects. Higher aqueous humor levels of TGF-β2 with age and in Af-Am population may explain the increase risk of these groups for developing open angle glaucoma.
Keywords: aqueous • cataract