Enhanced recombinant adeno-associated virus-mediated vascular endothelial growth factor expression in the adult mouse retina: a potential model for diabetic retinopathy.
Diabetic retinopathy, one of the most serious complications of long-term diabetes, could clinically be divided into two stages: 1) background retinopathy that does not cause visual impairment and 2) proliferative retinopathy, which is a potentially blinding condition. This study aims to investigate the correlation between enhancement of vascular endothelial growth factor (VEGF) expression and neovascular changes. A binary recombinant adeno-associated virus construct producing green fluorescent protein (GFP) and VEGF under the control of the human cytomegalovirus promoter, recombinant adeno-associated virus (rAAV).VEGF.GFP, was produced and injected into the subretinal space of C57BL mice. GFP expression was tracked by fluorescence fundus photography, and VEGF expression was confirmed by immunohistochemistry and enzyme-linked immunoassay. Neovascular changes were monitored by fluorescein angiography and histology and by quantifying the number of inner retinal vessels. GFP expression was found in 100% of injected eyes, and vascular changes were detected in 9 of 10 rAAV.VEGF.GFP-injected eyes. Of these, four demonstrated microaneurysms and five showed moderate to severe leakage. There was a statistically significant increase in blood vessel number in the inner nuclear layer (P < 0.03) and dilatation of retinal veins (P < or = 0.05). This work has demonstrated that the development of different stages of diabetic retinopathy is closely correlated with an increased VEGF level in the retina.
Rakoczy
P Elizabeth
PE
Centre of Ophthalmology and Visual Science, the University of Western Australia, 2 Verdun Street, Nedlands, 6009 WA, Australia. rakoczy@cyllene.uwa.edu.au
Brankov
Meliha
M
Fonceca
Angela
A
Zaknich
Tammy
T
Rae
Ben C
BC
Lai
Chooi-May
CM
D000818:Animals; D003587:Cytomegalovirus / Q000235:genetics; D000229:Dependovirus / Q000235:genetics*; D003930:Diabetic Retinopathy / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D016228:Endothelial Growth Factors / Q000032:analysis / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D005451:Fluorescein Angiography; D015870:Gene Expression; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis / Q000235:genetics*; D008164:Luminescent Proteins / Q000235:genetics; D008222:Lymphokines / Q000032:analysis / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins; D012160:Retina / Q000737:chemistry / Q000378:metabolism*; D012171:Retinal Vessels / Q000473:pathology / Q000503:physiopathology; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D014664:Vasodilation
D016228:Endothelial Growth Factors; D036341:Intercellular Signaling Peptides and Proteins; D008164:Luminescent Proteins; D008222:Lymphokines; D011993:Recombinant Fusion Proteins; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D049452:Green Fluorescent Proteins