Abstract:

Abstract:Objective To investigate the expression and function of intravitreal injection of pigment epithelium-derived factor (PEDF) gene eukaryotic expression vector in proliferative vitreoretinopath (PVR) model eye,and to clarify the inhibitory effect of PEDF gene transfection on PVR  induced by macrophages in rats. Methods The pcDNA3-PEDF with cationic liposome was injected into vitreous of 36 SD rats (the right eye of each rat as the experimental eye and the left eye as the negative control eye).The rats were divided into PVR control group (injecting macrophages in the vitreous cavity to induce PVR),saline control group (injecting macrophages 3 d after intravitreal injection of saline) and transfection group (injecting macrophages 3 d after intravitreal injection of liposome and  pcDNA3-PEDF),and there were 12 rats in each group.Then the ophthalmoscope and fundus pre-set lens were used to observe the vitreous and retinal conditions of the rats in each group;the stuctures of the  vitreous and retinal layers and the cell proliferation of the specimens of the  rats in various groups were detected by HE staining  under light microscope.Results The ophthalmoscope and fundus pre-set lens results showed that  after intravitreal injection of macrophages,there was  more significant vitreous proliferation in PVR control group and saline control group compared with transfection group 1 week after injection,there was vitreous proliferation in PVR control group and saline control group.2-3 weeks after injection,the proliferation was gradually increased and retina began to detach in PVR　control group and saline control group.4 weeks after injection,there was significant proliferation in all model eyes,and traction retinal detachment occurred in PVR control group and saline control group.Only one   eye of the rats in transfection group showed vitreous traction and shallow retinal detachment,and the other eyes  were normal.The HE staining and light microscope results showed that  the structurs of retina cells of most eyes  were  clear,only one eye occured shallow retinal detachment  with epiretinal membrane proliferation and  small amount of inflammatory cell infiltration in transfection group.There was inflammatory response with the progression of the disease,accumulation of inflammatory cells,proliferation of fibroblasts, and  formation of eyeball atrophy in PVR control group and saline control group. Conclusion PEDF transfected by intravitreal injection in rats’ eyes
can significantly inhibit the  formation and development of PVR induced by macro
phages.