Self-complementary AAV virus (scAAV) safe and long-term gene transfer in the trabecular meshwork of living rats and monkeys.

Kaufman Lab // Publications // Jan 01 2010

PubMed ID: 19684004

Author(s): Buie LK, Rasmussen CA, Porterfield EC, Ramgolam VS, Choi VW, Markovic-Plese S, Samulski RJ, Kaufman PL, Borrás T. Self-complementary AAV virus (scAAV) safe and long-term gene transfer in the trabecular meshwork of living rats and monkeys. Invest Ophthalmol Vis Sci. 2010 Jan;51(1):236-48. doi: 10.1167/iovs.09-3847. Epub 2009 Aug 13. PMID 19684004

Journal: Investigative Ophthalmology & Visual Science, Volume 51, Issue 1, Jan 2010

PURPOSE AAV vectors produce stable transgene expression and elicit low immune response in many tissues. AAVs have been the vectors of choice for gene therapy for the eye, in particular the retina. scAAVs are modified AAVs that bypass the required second-strand DNA synthesis to achieve transcription of the transgene. The goal was to investigate the ability of AAV vectors to induce long-term, safe delivery of transgenes to the trabecular meshwork of living animals.

METHODS Single doses of AAV2.GFP and AAV2.RGD.GFP/Ad5.LacZ were injected intracamerally (IC) into rats (n = 28 eyes). A single dose of scAAV.GFP was IC-injected into rats (n = 72 eyes) and cynomolgus monkeys (n = 3). GFP expression was evaluated by fluorescence, immunohistochemistry, and noninvasive gonioscopy. Intraocular pressure (IOP) was measured with calibrated tonometer (rats) and Goldmann tonometer (monkeys). Differential expression of scAAV-infected human trabecular meshwork cells (HTM) was determined by microarrays. Humoral and cell-mediated immune responses were evaluated by ELISA and peripheral blood proliferation assays.

RESULTS No GFP transduction was observed on the anterior segment tissues of AAV-injected rats up to 27 days after injection. In contrast, scAAV2 transduced the trabecular meshwork very efficiently, with a fast onset (4 days). Eyes remained clear and no adverse effects were observed. Transgene expression lasted >3.5 months in rats and >2.35 years in monkeys.

CONCLUSIONS The scAAV viral vector provides prolonged and safe transduction in the trabecular meshwork of rats and monkeys. The stable expression and safe properties of this vector could facilitate the development of trabecular meshwork drugs for gene therapy for glaucoma.