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Abstract #3708 Published in IGR 4-2
Adenovirus-mediated gene therapy using human p21WAF-1/Cip 1 to prevent wound healing in a rabbit model of glaucoma filtration surgery
Perkins TW; Faha B; Ni M; Kiland JA; Poulsen GL; Antelman D; Atencio I; Shinoda J; Sinha D; Brumback LArchives of Ophthalmology 2002; 120: 941-949
OBJECTIVE: To determine if adenovirus-mediated p21(WAF-1/Cip-1) (p21) gene therapy can prevent fibroproliferation and wound healing in a rabbit model of glaucoma filtration surgery. METHODS: In vitro studies were performed using rabbit Tenon fibroblasts harvested from fresh tissue. In vivo studies were conducted in New Zealand white rabbits. A full-thickness sclerotomy was performed under a limbal-based conjunctival flap. Reagents tested included a replication-deficient recombinant adenovirus containing the human p21 gene (rAd.p21); the nonspecific marker gene for green fluorescent protein or beta-galactosidase; mitomycin, 0.5 mg/ml; and balanced saline solution. Each treatment was applied episclerally for five minutes before the sclerotomy using a soaked cellulose sponge placed under the surgically created conjunctival flap. Independent experiments were conducted: (1) to monitor changes in intraocular pressure during a 30-day period after treatment and examine surgical site histological features; (2) to examine changes in bleb morphological features over 30 days; (3) to determine outflow facility 14 days after treatment; and (4) to examine the localization and persistence of rAd.p21 expression between three and 60 days after treatment. RESULTS: Treatment of tenon fibroblasts with rAd.p21 resulted in a dose-dependent inhibition of DNA synthesis and cell growth in vitro. In vivo, rAd.p21 inhibited wound healing and fibroproliferation after filtration surgery, comparably to mitomycin. Mitomycin caused notable thinning of the bleb wall. In addition, two of the 5 mitomycin-treated eyes exhibited an abscess with hypopyon and hyalitis 30 days after surgery, which was not observed in any of the rAd.p21-treated eyes. None of the treatments resulted in a significantly sustained decrease in intraocular pressure during the 30-day period, although mitomycin treatment resulted in a significant (p = 0.02) increase in outflow facility two weeks after surgery in separate animals. Mitomycin- and rAd.p21-treated eyes had functioning blebs at the end of the experiment based on slit-lamp examination. CONCLUSIONS: Mitomycin and rAd.p21 were effective in preventing fibroproliferation and wound healing in a rabbit model of glaucoma surgery. Mitomycin treatment increased outflow facility in normal-pressure eyes. CLINICAL RELEVANCE: Gene therapy with rAd.p21 may provide an effective antiproliferative for glaucoma filtration surgery, without the complications associated with mitomycin.
Dr. T.W. Perkins, Department of Ophthalmology and Visual Sciences, University of Wisconsin, 1300 University Avenue, Room 6640 MSC, Madison, WI 53706-1532, USA
Classification:
12.8.10 Woundhealing antifibrosis (Part of: 12 Surgical treatment > 12.8 Filtering surgery)
