Fig. 4

PEDF-sEVs suppress retinal neovascularisation and vaso-obliteration in OIR mice. A A schematic diagram showing the treatment of OIR mice with PBS, PEDF, sEVs, a mixture of PEDF and sEVs without sonication, anti-VEGF drugs, or PEDF-sEVs through intravitreal injection on P12. Pups were sacrificed and eyes were dissected on P17, P25, or P42. B The expression of PEDF and VEGF in the retinas of NOR and OIR mice on P12, P14, and P17. NOR refers to the normal C57BL/6J mice kept in room air that have not undergone hyperoxia. C Relative expression of PEDF and VEGF compared with that of GAPDH (n = 6 mice/group). D PCR analysis of PEDF and VEGF gene expression in the retinas of NOR and OIR mice on P12, P14, and P17 (n = 6 mice/group). E Representative confocal images of retinal vasculature stained with IsoB4 of OIR mice treated with PBS, PEDF, sEVs, a mixture, anti-VEGF drugs, or PEDF-sEVs on P17; scale bar = 500 μm. F Quantitative analysis of avascular area/total retinal area (n = 5 mice/group). G Quantitative analysis of neovascularisation/total retinal area (n = 5 mice/group). H VEGF expression in the retinas of OIR mice treated with PBS, PEDF, sEVs, and PEDF-sEVs on P17. I Relative expression of VEGF compared with that of GAPDH (n = 9 mice/group). J PCR analysis of VEGF gene expression in the retinas of OIR mice treated with PBS, PEDF, sEVs, and PEDF-sEVs on P17 (n = 6 mice/group). K VEGF expression in the retinas of OIR mice treated with PBS, anti-VEGF drugs, and PEDF-sEVs on P17. L Relative expression of VEGF compared with that of GAPDH (n = 6 mice/group). The data are represented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001