title: Adeno-associated vector (type 8)-mediated expression of soluble Flt-1 efficiently inhibits neovascularization in a murine choroidal neovascularization model.
abstract: To assess the feasibility of a gene therapeutic approach to treating choroidal neovascularization (CNV), we generated a recombinant adeno-associated viral (AAV) vector (type 8) encoding soluble Flt-1 (AAV-sflt-1), and determined its ability to inhibit angiogenesis. When we treated human umbilical vein endothelial cells (HUVECs) with the supernatant of cells transduced with AAV-sflt-1 or AAV-EGFP (control), we found that tube formation was significantly inhibited by the former but not the latter (area: 25,121 +/- 557 vs. 68,628 +/- 1357 pixels [p < 0.01]; length: 4811 +/- 246 vs. 10,894 +/- 297 pixels [p < 0.01]). CNV was induced in C57BL/6 mice by making four separate choroidal burns around the optic nerve in each eye, using a diode laser. Thereafter, 2 microl (5 x 10(11) vector genomes/ml) of AAV-sflt-1 (n = 11) or control AAV-LacZ (n = 12) was injected into the subretinal space, and 2 weeks later the eyes were removed for flatmount analysis of CNV surface area. Notably, subretinal delivery of AAV-sflt-1 significantly diminished CNV at the laser lesions, as compared with AAV-LacZ (555 +/- 304 vs. 1470 +/- 1000 microm(2); p = 0.007). These results suggest that there was diffusion of the secreted sFlt-1 across the retina and that long-term suppression of CNV is possible through the use of stable rAAV-mediated sflt-1 expression. In vivo gene therapy thus appears to be a feasible approach to the clinical management of CNV in conditions such as age-related macular degeneration.
authors.affiliation: Department of Ophthalmology, Research Center for Advanced Medical Technology, Nippon Medical School, Bunkyo-ku, Tokyo 113-8603, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Igarashi
authors.forename: Koichi
authors.initials: K
authors.lastname: Miyake
authors.forename: Ikuya
authors.initials: I
authors.lastname: Masuda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimada
mesh_terms: D000818:Animals; D002829:Choroid / Q000098:blood supply / Q000378:metabolism; D020256:Choroidal Neovascularization / Q000235:genetics / Q000378:metabolism* / Q000628:therapy*; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D007267:Injections; D007763:Lac Operon; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000378:metabolism / Q000628:therapy*; D012160:Retina / Q000378:metabolism; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000235:genetics / Q000378:metabolism
chemical_list: D040281:Vascular Endothelial Growth Factor Receptor-1