Figure 3. RT-PCR analysis. The vitreal cavity of rabbit eyes was injected with rAAV-IL-1Ra (4×10⁷ infectious units), and the contralateral eye was injected with the same amount of rAAV-LacZ. In another group, the right eye was injected with the same amount of PBS. Ten days later, the rabbit eyes were enucleated, extracted, and subjected to RT-PCR. No human IL-1Ra mRNA was observed in the rAAV-LacZ-injected (lane 1) or PBS-injected (lane 2) eyes. Significant transgene expression was observed in rAAV-IL-1Ra-injected eyes (lane 3). After 100 days, the eyes of different rabbits were enucleated, extracted, and subjected to RT-PCR. No human IL-1Ra mRNA was found in the rAAV-LacZ-injected (lane 4) or PBS-injected (lane 5) eyes. Significant transgene expression was still detected in the rAAV-IL-1Ra-injected eye (lane 6). Lane M shows the molecular weight markers.