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)
Objective To observe the influence of rAAV-mediated antisense vascular endothelial growth factor (rAAV-aVEGF165) on the expression of retinal VEGF in diabetic rats. Methods 40 Sprague-Dawley rats induced diabetic rat model by intraperitoneal injection with streptozotocin (STZ). 32 rats were involved in study besides death and blood sugar recovery in experimental process, 16 spragud-Dawleg (SD) rats were received intravitreal injection with rAAV-aVEGF165 (1010 pfu) as experimental group, another group of Sprague-Dawleg (SD) rats were injected with phosphate buffered saline (PBS) as control group. One and five month after model establishment, the expression of retinal VEGF was evaluate by immunhistochemistry and Western blot; the retinal vasular was examined by transmission electron microscopy. Results On 1 month,the expression of retinal VEGF was lowest in each group. On 5 month, the expression of retinal VEGF was decreased in experimental group which compared to control, the difference are statistically significant (t=23.87,Plt;0.01). The transmission electron microscopy results showed that retina has no obvious chages in experimental group, however,contral group showed fragmental thickening and splitting of basement membrane, swelling and deformation of endothelia cells,fingerlike prcess into the capillary cavity,and uneven distibution of heterochromatin in pericytes. Conclusion rAAV-aVEGF165 can reduce the expression of retinal VEGF thereby preventing occurrence and development of diabetic retinopathy. rAAV is an effective vectors of eye antisense gene. (Chin J Ocul Fundus Dis,2008,24:255-258)
Adeno-associated viral vector (AAV) is the most important viral tool and has been widely used in gene therapy. Because of its small size, non-enveloped, non-pathogenic and other characteristics, so it is one of the main means to treat hereditary retinal diseases. Aiming at MERTK for retinitis pigmentosa, ND4 for Leber hereditary optic neuropathy or RPE1 for choroideremia, AAV gene therapy improved half patients’ visual acuity in clinic tests. Besides, there are some clinic tests in progress for Leber’s congenital amaurosis, X-linked retinoschisis, Achromatopsia, age-related macular degeneration. But more researches need to be found before clinic test for Stargardt disease, Usher syndrome and nanophthalmos. At present, AAV gene therapy is mainly used for recessive hereditary retinal diseases, and technology is needed to intervene for dominant retinal diseases. For the treatment of hereditary retinal diseases, this will be an important and complex systematic project, which requires more human and material resources to participate in and study together, and we expect to have a great breakthrough in the near future.
OBJECTIVE: To review the research progress and medical application of nano-materials. METHODS: The literature review and comprehensive analysis, methods were used in this study. RESULTS: The Nanotechnology is a typical crossing knowledge. It could be extensively applied in the fields of novel biomaterials, effective transmission of bioactive factor; the detection of functions for all vital organ systems, vascular circulation condition, the control of repair of burn trauma wounds will be monitored by the varied methods of nano technology combined with molecular biological engineering. CONCLUSION: The application of Nanotechnology will play important roles in clinical medicine, wound repair and basic research for the traditional Chinese medicine.
Objective To investigate the inhibitive effect of E2F decoy oligodeoxynucleotides (E2F decoy ODNs) on cultured human retinal pigment epithelial (HRPE) cells.Methods E2F decoy ODNs or scramble decoy ODNs at varied concentrations were put into the HRPE cells mediated by lipofectamineTM2000. The proliferative activity of HRPE was detected by methythiazolyl-terazollium assay, and the competitive combinative activity of E2F decoy ODNs and transcription factor E2F was detected by electrophoresis mobility-shift assay. Results The proliferation of HRPE was inhibited markedly by E2F decoy ODNs at the concentration of 0.2 μmol/L (P=0.002) in a dose-dependent manner but not by scrambled decoy. The results of electrophoresis mobility-shift assay showed that the combinative activity of transcription factor E2F was abolished completely by E2F decoy ODNs. Conclusions E2F decoy ODNs may sequence-specifically inhibit the combinative activity of transcripti on factor E2F,and inhibit the proliferation of HRPE cells.(Chin J Ocul Fundus Dis,2004,20:182-185)
The application of gene therapy in ocular diseases is gradually expanding from mono-gene inherited diseases to multigene, multifactorial, common and chronic diseases. This emerging therapeutic approach is still in the early exploratory stage of treating diseases, and the expected benefits and risks remain highly uncertain. In the delivery process of gene therapy drugs, viral vector is currently one of the most mature and widely used vectors. The occurrence of vector-associated immunity will affect the short-term and long-term effects of gene therapy, and even cause permanent and serious damage to visual function. Therefore, gene therapy vector-associated immunity is the focus and challenge for the safety and long-term efficacy of gene therapy. During the perioperative and follow-up of gene therapy, attention should be paid to the monitoring of vector-associated immune inflammation, and appropriate measures should be taken to deal with the corresponding immune response, so as to achieve the best visual benefits for patients.
Objective To invesitgate the influence of recombinant adenovirus vector of human pigment epithelium-derived factor(AV-hPEDF)on retinal new vessels mediated by recombinant adenovirus vector. Methods Twenty 7-days-old Sprague-Dawley (SD) rat were divided into two groups randomly after the establishment of retinal neovascularization model. At postnatal 14 day, they were accepted intravitreal injection with blankadenovirus-vector (AV-Blank group) and adenovirus-vector PEDF(AV-PEDF group) respectively. The retinal vascular endothelial cells were counted, the PEDF mRNA and protein expression in retina and vitreous were determined by reverse transcriptionpolymerase chain reaction (RT-PCR) and immunohistochemistry. Results After injection with medicine, the number of RNV was decreased obviously in AV-PEDF group(t=42.009,Plt;0.001);the protein expression of retinal PEDF was increased obviously in AV-PEDF group(t=36.638,Plt;0.001); the PEDF mRNA expression in vitreous was also increased obviously in AV-PEDF group (t=9.128,Plt;0.001). Conclusion Recombinant Adenovirus vector mediated PEDF can raise the PEDF expression in the retinal and vitreous neovascularized tissues in rat, which suggested that the expression of PEDF may be related to inhibition and reduction of RNV.
ObjectiveTo detect the effect of adeno-associated-virus induced Kringles5 gene on retinal neovascularization in rats with retinopathy of prematurity (ROP), and to explore the new ways of treatment for ROP.MethodspSNAV-Kringle5-gfp carrier was constructed by subclone and adeno-associated-virus was packed to form rAAV-Kringle5-gfp. ROP model was set up under circumstances of high oxygen in 21 SD rats which were divided into experimental (21 eyes) and control group (21 eyes). Eighteen eyes from each group was used to making the histologic section of retina, and the other 3 eyes in each group was detected by polymerase chain reaction (PCR) and Western blotting. There were 5 rats in the normal control group. AAV-Kringle5-gfp with the dosage of 10 μl and titer of 2.5×1012vg/ml was injected into the eyes in experimental group, while rAAVlacZ with the same dosage and titer of 2.5×1011vg/ml was injected in to the eyes in control group. The expression of target gene in ocular tissues was observed under the fluoroscope. Twelve weeks later, the rats were executed, and the staining of Ⅷ factor related antigens in retinal vascular endothelial cells was performed and number of nucleolus of vascular endothelial cells were counted. ResultsThe plasmid of pSNAV-Kringle5-gfp was correct according to the sequence measurement; the expression of rAAV-Kringle5-gfp was found in vitreous cavity and on retina; the expression of target gene was found on the level of mRNA and protein; the number of nucleolus of vascular endothelial cells on the surface of retina was (19.954 2±3.825 7) in experimental group and (7.335 2±2.731 3) in the control group, which had significant difference between the two groups (P<0.01).ConclusionsAdeno-associated-virus induced Kringles5 gene can inhibit the occurrence of retinal neovascularization in patients with ROP.(Chin J Ocul Fundus Dis, 2005,21:288-291)
Objective To observe the protective effect of ultrasound microbubble contrast agentmediated transfection of brain-derived neurotrophic factor(BDNF) into the retina and visual cortex on retinal ganglion cells (RGC) after optic nerve injury. Methods A total of 88 male Sprague-Dawley (SD) rats were randomly divided into normal group (group A, eight rats), sham operation group (group B, 16 rats), control group (group C, 16 rats), eyes transfection group (group D, 16 rats), brain transfection group (group E, 16 rats), combined transfection group (group F, 16 rats). The optic nerve crush injury was induced, and then the groups B to F were divided into one-week and two-week after optic nerve injury subgroup with eight rats each, respectively. The rats in group B and C underwent intravitreal and visual cortex injection with phosphate buffered solution respectively. The rats in group D and E underwent intravitreal and visual cortex injection with the mixture solution of microbubbles and BDNF plasmids respectively. The rats in group F underwent both intravitreal and visual cortex injection with the mixture solution of microbubbles and BDNF plasmids at the same time. The ultrasound exposure was performed on the rats in group D to F after injection with the mixture solution of microbubbles and BDNF plasmids. One and two weeks after optic nerve injury, RGC were retrogradely labeled with Fluorogold; active caspase-3 protein was observed by immunohistochemistry and the N95 amplitude was detected by pattern electroretinogram (PERG). Results Golden fluorescence can be observed exactly in labeled RGC in all groups,the difference of the number of RGC between the six groups and ten subgroups were significant(F=256.30,65.18;P<0.01). Active caspase-3 in ganglion cell layer was detected in group C to F, but not in group A and B. The difference of the N95 amplitude between the six groups and ten subgroups were significant(F=121.56,82.38;P<0.01).Conclusion Ultrasound microbubble contrast agent-mediated BDNF transfection to the rat retina and visual cortex can inhibit the RGC apoptosis after optic nerve injury and protect the visual function.