Publishing date: December 2013
Author(s): Wallace DM, Clark AF, Lipson K, Andrews D, Crean J, O'Brien CJ.
PURPOSE: We have previously demonstrated elevated levels of Connective Tissue Growth Factor (CTGF/CCN2) in the aqueous humour (AqH) of pseudoexfoliation glaucoma (PXFG) patients when compared to cataract controls. Furthermore, there is a significant trabecular meshwork (TM) and lamina cribrosa (LC) fibrotic phenotype associated with glaucoma possibly driven by CTGF. The purpose of this study was to investigate the potential of anti-CTGF immunotherapy in glaucoma.
METHODS: Primary TM and LC cells were cultured from human donors with (GTM/GLC) and without (NTM/NLC) primary open angle glaucoma (POAG). AqH samples from PXFG, POAG and control cataract patients were applied to N/GTM and N/G LC cells in the presence or absence of a therapeutic, humanized monoclonal anti-CTGF antibody FG-3019 (10µg/ml) (FibroGen Inc.). Hydrogen peroxide, (H2O2) was also used as a stimulus. Expression of fibrotic genes (fibronectin-1, fibrillin-1, CTGF, collagen 1A1 and a-smooth muscle actin) was assessed by q-PCR. Protein expression of collagen 1A1 and a-smooth muscle actin was examined in N/G TM cells by SDS-PAGE. The modulatory effect of FG3019 (10µg/ml) and IgG (10µg/ml) were also assessed.
RESULTS: Treatment of cells with AqH from PXFG & POAG patients and H2O2 induced a significant (P<0.05) increase in expression of pro-fibrotic genes, which was significantly reduced by pre-treatment with FG-3019 (P<0.05). FG-3019 also reduced expression of a-smooth muscle actin and collagen 1A1 protein expression in N/G TM cells.
CONCLUSIONS: FG-3019 is effective in blocking extracellular matrix production in TM and LC cells thus supporting a role for the use of anti-CTGF immunotherapy in the treatment of glaucoma.
Invest Ophthalmol Vis Sci. 2013 Nov 7. pii: iovs.13-12494v1. doi: 10.1167/iovs.13-12494.
Experimental Paper of the Month manager: Andreas Boehm