Trabeculectomy is the standard surgical intervention to reduce intraocular pressure in subjects no longer sufficiently responding to pressure-lowering medications. Scarring of the surgically opened canal (bleb) often abolishes the effect of trabeculectomy (despite the intraoperative use of Mitomycin C to prevent this). TGF-β2 has been described to play a distinct role in the fibrotic process of bleb closure.