Purpose To study the possibility of prevention of proliferative vitreoretinopathy(PVR) by transduction of exogenous gene in vivo. Methods PVR model of rabbits was induced by intravitreal injection of fibroblasts.beta;-galactosidase (lacZ) gene as a reporter gene was transfered into the vitreous of PVR model eyes mediated by retroviral vector, and the expression of the gene in eye tissues was determined . Gene transfection was done on the 6th day after fibroblasts injection,and the dosage of intravitreal injection of reporter gene was 0.1ml PLXSN/lacZ serum-free supernatant (1.1times;106 cfu/ml). Results lacZ gene expression was seen in proliferative membranes after gene transfection, and the expression was located maily at the surface of PVR membrane.The reporter gene expression lasted at least more than 30 days.No expression was found in retinal tissues. Conclusions Retrovirus mediated gene can be directionally transducted in PVR membrane,and might possess the feasibility of gene therapy for PVR. (Chin J Ocul Fundus Dis, 2001,17:224-226)
One hundred and eighty-nine cases of retinal detachment complicated with advanced proliferative vitreoretinopathy (grade C or D)were treated with scleral buckling or vitreous surgery,The reattachment rate was 63% ,ranging from 87.5% in grade C1 to 30.4% in grade D3.Retinas were reattached in 119,of which the postoperative visual acuity was counting finger or better in 95.8% and 20/200 or better in 26.9% in those cases,of grade C1 to C2 without proliferative vitreoretinopathy. The major causes of surgical failure were development of new or recurrent anterior PVR(51.4%),posterior epiretinal proliferation making pre-existing retinal breaks open and creation of new breaks (25.7%). Finally,we discussed the time of vitreoretinal surgery,methods of operation and the formation of anterior PVR. (Chin J Ocul Fundus Dis,1994,10:199-202)
Our previous experiments showed limited results of treatment with daunomycin when given at the inflammatory stage of proliferative vitreoretinopathy(PVR)induced by macrophages in rabbits.In the present study,we observed the inhibition of intraocular cellular proliferation in the same model by daunomycin which was injected in a dosage of 5mu;g 6 days after intravitreal macrophage injection,with 3H-thymidine autoradiography.The efficacy of daunomycin was also compared with that of triamcinolone,and combined triamcinlone and daunomycin.The retinal detachment occurred in 33.3%,16.1%,8.3%and 83.3%(P<0.01) of the eyes treated with daunomycin,triamcinolone,combined drugs and the control groups,respectively.Autoradiography revealed a singnificantly decreased number of labelled nuclei of proliferative cells on days 7 and 14 in daunomycin-treated eyes(compared to controls,18.8plusmn;3.2 vs 35.7plusmn;3.4;52.1plusmn;8.0 vs 81.3plusmn;14.6,P<0.01,respectively).Significantly decreased numbers of inflammatory cells and labelled cells were also noted in eyes treated with triamcinolone and combined drugs.The results suggest that daunomycin given at the proliferative stage,and triamcionlone given at the inflammatory stage of PVR,or combined drugs can prevent traction retinal detachment. (Chin J Ocul Fundus Dis,1994,10:229-231)
The stimulating effects of subretinal fluid (SRF) of 31 patients with rhegnmtoganous retinal detachment (among them 5 are recurrent) on the growth of fihroblasts were investigated. The results demonstrated that all samples of SRF showed stimulating effect in a variable degree.The range of proliferation-stimulating activity was from 86. 7% to 366.7% above the baseline.The stimulating ahility was mainly related to the degree of PVR and may be also related to the extent and clinical course of the detaehrnent. When stimulating rate was S0Y0 ,the dilution multiple of SRF was higher in recurrent patients than that in initiate ( P<0.01). (Chin J Ocul Fundus Dis,1993,9:11-13)
The classical Hippo pathway leads to the phosphorylation of downstream effector molecules Hippo-Yes-associated protein (Yap) and transcriptional coactivator PDZ-binding motif (Taz) serine sites through a kinase response, thereby promoting cell proliferation, controlling cell polarity, changing cytoskeleton, it plays an important regulatory role in various pathophysiological processes such as epithelial-mesenchymal transition and inhibition of cell contact. Studies have shown that Yap/Taz can affect the progression of vitreoretinal diseases, opening up new prospects for the pathogenesis and clinical treatment of diabetic retinopathy, proliferative vitreoretinopathy, and retinal ischemia-reperfusion injury. Exploring the molecular mechanism of Yap/Taz provides a possible therapeutic target for future research in the treatment of retinal fibrosis diseases such as diabetic retinopathy and proliferative vitreoretinopathy. At the same time, regulating the activity of local Yap/Taz in the retina will also become an effective therapeutic target for damage-repair in retinal ischemia-reperfusion injury. However, Yap inhibitors have potential retinal toxicity and are still in the preclinical development stage. Further research on the mechanism of action and clinical safety of Yap inhibitors will provide new methods for the treatment of retinal diseases.