title: Suppression of choroidal neovascularization by intramuscular polymer-based gene delivery of vasostatin.
abstract: The purpose of this study was to evaluate the efficacy of gene delivery of angiogenesis inhibitor, vasostatin (VS), in suppressing experimental model of choroidal neovascularization (CNV). A mammalian expression vector carrying VS, pCMV3-VS, was constructed and evaluated for its ability to produce VS in transfected cells using western blot analysis and a cell viability assay. CNV was induced in Brown Norway rats by fundus argon laser photocoagulation and evaluated by fundus fluorescein angiography (FAG). Ten days post-laser treatment, gene delivery was achieved by intramuscular (IM) injection of poly-(N-vinyl pyrrolidone) (PVP) polymer conjugated with pCMV3-VS (PVP-VS) or a control vector (PVP-vector). Systemic VS expression was analysed by western blot analysis and enzyme linked immunosorbent assay (ELISA), and the extent of CNV was monitored by FAG analysis at different time intervals post-PVP treatment. Transfection of pCMV3-VS into muscle cells resulted in increased production and release of exogenous VS, which specifically inhibited the proliferation of endothelial cells. Besides, IM injection of PVP-VS, but not PVP-vector, led to elevated VS level in plasma for 30 days. After laser photocoagulation, rats injected with PVP-VS exhibited significantly lower incidence of CNV comparing with animals of control groups (P < 0.01) for at least 42 days. Moreover, rats treated with PVP-VS also showed a significant reduction in the CNV lesions compared with control groups (P < 0.001) for at least 42 days. Above all, no overt adverse effects were observed in rats received PVP-VS. These results demonstrate the potential of IM VS gene delivery for CNV treatment.
authors.affiliation: Department of Ophthalmology, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan, ROC.
authors.forename: Shwu-Jiuan
authors.initials: SJ
authors.lastname: Sheu
authors.forename: Li-Chen
authors.initials: LC
authors.lastname: Chou
authors.forename: Youn-Shen
authors.initials: YS
authors.lastname: Bee
authors.forename: Jane-Fane
authors.initials: JF
authors.lastname: Chen
authors.forename: Hsiu-Chen
authors.initials: HC
authors.lastname: Lin
authors.forename: Pey-Ru
authors.initials: PR
authors.lastname: Lin
authors.forename: Hsing-Chun
authors.initials: HC
authors.lastname: Lam
authors.forename: Ming-Hong
authors.initials: MH
authors.lastname: Tai
mesh_terms: D020533:Angiogenesis Inhibitors / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D037282:Calreticulin / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D020256:Choroidal Neovascularization / Q000209:etiology / Q000517:prevention & control*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005240:Feasibility Studies; D015870:Gene Expression; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D007273:Injections, Intramuscular; D008028:Light Coagulation; D010446:Peptide Fragments / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D011914:Rats, Inbred BN; D014162:Transfection
chemical_list: D020533:Angiogenesis Inhibitors; D037282:Calreticulin; D010446:Peptide Fragments; C121986:vasostatin