The Inhibitory Effect of Connective Tissue Growth Factor Antibody on Postoperative Fibrosis in a RabbitModel of Trabeculectomy

Purpose: to compare the efficacy of subconjunctival injection of an anti-connective tissue growth factor antibody (anti-ctgf) versus mitomycin-c (mmc) and placebo in reducing scar formation in a rabbit model of trabeculectomy. methods: a total of 14 rabbits were included. nine rabbits underwent trabeculectomy with subconjunctival injections of either anti-ctgf antibody, mmc, or balanced salt solution (bss), each administered in three eyes, before peritomy. the anti-ctgf group received a repeated dose of the antibody five days after surgery. all nine rabbits were euthanized on day 14; the globes were stained with hematoxylin & eosin, masson’s trichrome, and immunohistochemistry for detecting alpha-smooth muscle (α-sma) actin. rna extraction was performed on five eyes of the remaining rabbits which included one eye without any surgery, one eye 5 hr after trabeculectomy without any injection, one eye five days after trabeculectomy without any injection, and two eyes five days after trabeculectomy with administration of mmc and bss, respectively. results: the mean bleb area in the anti-ctgf, mmc, and control groups was 3.8 ± 1.45, 5.9 ± 1.4, and 3.5 ± 1.9 mm2, respectively. collagenous tissue was found to occupy the bleb area by 13.7%, 13.5%, and 18.5%, respectively. this ratio was significantly higher in the bss group (p = 0.04). the expression of ctgf mrna after 5 hr and five days in eyes undergoing trabeculectomy were significantly more pronounced as compared to the unoperated eye. the mean h-score of α-sma-immune reactive cells calculated as the grade of staining multiplied by the percentage of immune stained cells was 14.6, 10.22,and 140.58 in the anti-ctgf, mmc, and control groups, respectively. while the control eyes had a significantly higher score (ps < 0.001), the anti-ctgf and mmc groups were comparable (p = 0.87). conclusion: based on the results of this animal study, the anti-ctgf antibody injection resulted in a significant reduction in collagenous tissue and myofibroblast cells after trabeculectomy.