Sustained transduction of ocular cells with a bovine immunodeficiency viral vector

Human immunodeficiency viral (HIV) vectors mediate long-term transduction of many types of nondividing cells in vivo. Bovine immunodeficiency virus (BIV) is a lentivirus that shares many characteristics with HIV, but does not cause human disease. In this study, we investigated the potential of BIV vectors for ocular gene therapy. An enhanced green fluorescent protein (eGFP)-encoding reporter gene was packaged in recombinant BIV vector (BIV.eGFP). Adult C57BL/6 mice were given an intravitreous (5 × 104 or 5 × 105 transducing units [TU]) or subretinal (5 × 105 TU) injection of BIV.eGFP and then GFP expression was assessed at several time points. In vivo examinations of mice showed that subretinal injection of BIV.eGFP resulted in strong expression of GFP from the first examination at 1 week through the final examination at 20 weeks. Only a few mice that received intravitreous injection of BIV.eGFP showed GFP expression by ocular examinations until 11-12 weeks, when most showed small areas of expression. Pos...