Abstract： Objective To investigate the inhibitory effect oflentivirus-mediated polypyrimidine bundle binding protein-associated splicing factor (PSF) on retinal neovascularization (RNV) in mice model of oxygeninduced retinopathy (OIR).Methods One hundred and twelve 5-day-old C57BL/6J mice were randomly divided into normal control group,simple OIR model group,OIR model + lentivirus empty vector treatment group (Vec group) and OIR model + PSF lentivirus treatment group (PSF group),with 16,32,32 and 32 mice,respectively.When the mice were 7 days old,the mice in the normal control group were fed in a routine environment,and the mice in the OIR model group,Vec group and PSF group were established OIR model.The mice in the Vec group and PSF group were given an intravitreal injection of 1 μl of lentiviral vector and PSF lentivirus (titer 1 × 10~ TU/ml) at the age of 12 days.No injection was performed in the normal control group and simple OIR group.RNV was evaluated by counting the number of pre-retinal neovascular cells and analysis of non-perfusion area by immunofluorescent staining of the mouse retina.Real-time quantitative PCR was applied to detect the mRNA expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase1 (HO-1).Western blot analysis was applied to detect the protein expression ofNrf2,HO-1 and PSF.Results Of the normal control group,simple OIR model group,Vec group and PSF group,the number of pre-retinal neovascular cell nuclei were 0.00,14.36 ± 5.50,15.67 ± 4.96,8.13 ± 2.09,the non-perfusion area were 0.00％,(35.71 ± 2.81)％,(36.57 ± 4.53)％,(15.33 ± 4.75)％,respectively.The differences of the number of pre-retinal neovascular cell nuclei and non-perfusion area among 4 groups were significant (F=24.87,165.70;P＜0.05).Compared with the normal control group,there were more pre-retinal neovascular cell nucleis and larger nonperfusion area in the simple OIR model group and Vec group (P＜0.05).Compared with the simple OIR model group and Vec group,there were lower pre-retinal neovascular cell nucleis and smaller non-perfusion area in the PSF group (P＜0.05).Real-time quantitative PCR and Western blot showed that the mRNA expression of Nrf2,HO-1 (F=53.66,83.54) and protein expression ofNrf2,HO-1 and PSF (F=58.38,52.69,24.79) among 4 groups were significant (P＜0.05).The rnRNA expression ofNrf2,HO-1 and protein expression of Nrf2,HO-1 and PSF in the simple OIR model group and Vec group decreased significantly than those in the normal control group (P＜0.05).The mRNA expression ofNrf2,HO-1 and protein expression ofNrf2,HO-1 and PSF in the PSF group were increased significantly than those in the simple OIR model group and Vec group (P＜0.05).model group and Vec group (P＜0.05).Conclusion Intravitreal injection of lentivirus-mediated PSF inhibits RNV in mice model of OIR possibly through up-regulating the expression of Nrf2 and HO-1.