Time-course of experimental choroidal neovascularization in Dutch-Belted rabbit: clinical and histological evaluation.

In order to study the pathogenesis of choroidal neovascularization (CNV) and explore a suitable animal model for assessing anti-angiogenic agents, rabbit CNV was induced by subretinal injection of a cocktail containing endotoxin and growth-factor, incorporated in Heparin-sepharose beads. The presence and development of CNV lesions was visualized by fluorescein angiography and quantified by image analysis. The time-course of experimental CNV was evaluated clinically and histologically, with some lesions followed up to 3-years. The suitability of this model for drug evaluation was appraised by the systemic administration of dexamethasone. The experimental results suggest two subsets of CNV, primary and secondary, observed in all treated eyes. Primary CNV, defined as neovascularization extending into the subretinal space and associated with injury to Bruch's membrane at the time of injection, was visible in 100% of eyes by 2-weeks and stable by 3-months. Secondary CNV, defined as neovascularization extending into the sub RPE space away from the initial injection related injury, became visible as early as 2-weeks in some of eyes and developed in 100% of eyes by 8-months. Both primary and secondary CNV were maintained and demonstrated leakage throughout the entire observation period. Atrophy of primary retinal pigmented epithelium (RPE) cells and hyper-proliferation of secondary RPE cells were observed in tissue sections with CNV lesions. The formation and growth of primary and secondary CNV were significantly inhibited by dexamethasone. This study indicates that a reproducible and quantitative model of rabbit CNV has been established utilizing subretinal administration of endotoxin and growth-factor. Studies of the stages of experimental CNV both clinically and histologically indicated an intimate relationship between CNV, macrophages and RPE. Furthermore, the inhibition observed with dexamethasone points to the possibility of being able to evaluate effective means of pharmacological intervention.

[1]  R. D'Amato,et al.  Strain‐dependent anterior segment neovascularization following intravitreal gene transfer of basic fibroblast growth factor (bFGF) , 2001, The journal of gene medicine.

[2]  P. Campochiaro,et al.  Retinal and choroidal neovascularization , 2000, Journal of cellular physiology.

[3]  B. Griffin,et al.  Topical formulations of novel angiostatic steroids inhibit rabbit corneal neovascularization. , 1997, Investigative ophthalmology & visual science.

[4]  J. Grunwald,et al.  Changes in Choriocapillaris and Retinal Pigment Epithelium ( RPE ) in Age-Related Macular Degeneration , 1999 .

[5]  M. Zarbin,et al.  Age-Related Macular Degeneration: Review of Pathogenesis , 1998, European journal of ophthalmology.

[6]  K. Nakagawa,et al.  Expression of vascular endothelial growth factor in experimental choroidal neovascularization , 1997, Graefe's Archive for Clinical and Experimental Ophthalmology.

[7]  P. Campochiaro,et al.  Cell injury unmasks a latent proangiogenic phenotype in mice with increased expression of FGF2 in the retina , 2000, Journal of cellular physiology.

[8]  M. Mandai,et al.  Inhibitory effect of TNP-470 on experimental choroidal neovascularization in a rat model. , 1999, Investigative ophthalmology & visual science.

[9]  R. Frank,et al.  Growth factor localization in choroidal neovascular membranes of age-related macular degeneration. , 1994, Investigative ophthalmology & visual science.

[10]  R. Frank.  Growth factors in age-related macular degeneration: pathogenic and therapeutic implications. , 1997, Ophthalmic research.

[11]  J. Marshall,et al.  Expression of metalloproteinases from human retinal pigment epithelial cells and their effects on the hydraulic conductivity of Bruch's membrane. , 2002, Investigative ophthalmology & visual science.

[12]  P. Campochiaro,et al.  The pathogenesis of choroidal neovascularization in patients with age-related macular degeneration. , 1999, Molecular vision.

[13]  F. Luscinskas,et al.  MCP-1 and IL-8 trigger firm adhesion of monocytes to vascular endothelium under flow conditions , 1999, Nature.

[14]  C. Puliafito,et al.  A new model of experimental choroidal neovascularization in the rat. , 1989, Archives of ophthalmology.

[15]  S. Marcus,et al.  Activation of progelatinase A (MMP‐2) by neutrophil elastase, cathepsin G, and proteinase‐3: A role for inflammatory cells in tumor invasion and angiogenesis , 2001, Journal of cellular physiology.

[16]  T. Hla,et al.  Lysophospholipids--Receptor Revelations , 2001, Science.

[17]  M. Uyama,et al.  Expression of transforming growth factor-beta mRNA in experimental choroidal neovascularization. , 1997, Current eye research.

[18]  G. Chader,et al.  Animal models in research on retinal degenerations: past progress and future hope , 2002, Vision Research.

[19]  Y. Mori,et al.  Differential roles of ICAM-1 and E-selectin in polymorphonuclear leukocyte-induced angiogenesis. , 2002, American journal of physiology. Cell physiology.

[20]  Y. Ikada,et al.  Cellular response in subretinal neovascularization induced by bFGF-impregnated microspheres. , 1999, Investigative ophthalmology & visual science.

[21]  T. Hisatomi,et al.  The critical role of ocular‐infiltrating macrophages in the development of choroidal neovascularization , 2003, Journal of leukocyte biology.

[22]  R. Strieter,et al.  IL-4 potentiates IL-1beta- and TNF-alpha-stimulated IL-8 and MCP-1 protein production in human retinal pigment epithelial cells. , 1999, Current eye research.

[23]  M. Uyama,et al.  Expression of basic fibroblast growth factor mRNA in developing choroidal neovascularization. , 1996, Current eye research.

[24]  Cord Sunderkötter,et al.  Macrophages and angiogenesis , 1994, Journal of leukocyte biology.

[25]  K. Csaky,et al.  Macrophage depletion diminishes lesion size and severity in experimental choroidal neovascularization. , 2003, Investigative ophthalmology & visual science.

[26]  J L Edelman,et al.  Quantitative image analysis of laser-induced choroidal neovascularization in rat. , 2000, Experimental eye research.

[27]  D. S. Mcleod,et al.  Quantifying changes in RPE and choroidal vasculature in eyes with age-related macular degeneration. , 2002, Investigative ophthalmology & visual science.

[28]  K. Schulze-Osthoff,et al.  Macrophage-derived angiogenesis factors. , 1991, Pharmacology & therapeutics.

[29]  J. Ambati,et al.  Macrophage depletion inhibits experimental choroidal neovascularization. , 2003, Investigative ophthalmology & visual science.

[30]  M. P. Hartmann,et al.  Basic fibroblast growth factor experimentally induced choroidal angiogenesis in the minipig. , 1994, Current eye research.

[31]  D. Hinton,et al.  Promotion of adhesion and migration of RPE cells to provisional extracellular matrices by TNF-alpha. , 2000, Investigative ophthalmology & visual science.

[32]  Beatriz Munoz,et al.  Causes of blindness and visual impairment in a population-based sample of U.S. Hispanics. , 2002, Ophthalmology.

[33]  K. Suzuma,et al.  The potential angiogenic role of macrophages in the formation of choroidal neovascular membranes. , 1999, Investigative ophthalmology & visual science.

[34]  P. D'Amore,et al.  Mechanisms of retinal and choroidal neovascularization. , 1994, Investigative ophthalmology & visual science.

[35]  Eiji Sakurai,et al.  An animal model of age-related macular degeneration in senescent Ccl-2- or Ccr-2-deficient mice , 2003, Nature Medicine.

[36]  J. Yanni,et al.  Angiostatic activity of steroids in the chick embryo CAM and rabbit cornea models of neovascularization. , 1999, Journal of ocular pharmacology and therapeutics : the official journal of the Association for Ocular Pharmacology and Therapeutics.

[37]  S. Ryan,et al.  The development of an experimental model of subretinal neovascularization in disciform macular degeneration. , 1979, Transactions of the American Ophthalmological Society.

[38]  K. Csaky,et al.  Age as an independent risk factor for severity of experimental choroidal neovascularization. , 2002, Investigative ophthalmology & visual science.

[39]  T. Maciag,et al.  The heparin-binding (fibroblast) growth factor family of proteins. , 1989, Annual review of biochemistry.

[40]  R. Danis,et al.  The squirrel monkey: characterization of a new-world primate model of experimental choroidal neovascularization and comparison with the macaque. , 2004, Investigative ophthalmology & visual science.

[41]  H. Grossniklaus,et al.  Macrophage and retinal pigment epithelium expression of angiogenic cytokines in choroidal neovascularization. , 2002, Molecular vision.

[42]  Z. Werb,et al.  Matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 in the retinal pigment epithelium and interphotoreceptor matrix: vectorial secretion and regulation. , 1997, Experimental eye research.

[43]  A. Hendrickson,et al.  Normal and pathological mechanisms in retinalvascular development , 1996 .

[44]  J. Carrascosa,et al.  An immunohistopathologic study in cutaneous necrotizing vasculitis , 2000, Journal of cutaneous pathology.

[45]  D. Eliott,et al.  Basic fibroblast growth factor and vascular endothelial growth factor are present in epiretinal and choroidal neovascular membranes. , 1996, American journal of ophthalmology.

[46]  M. Matsumura,et al.  Expression of pigment epithelium derived factor and vascular endothelial growth factor in choroidal neovascular membranes and polypoidal choroidal vasculopathy , 2004, British Journal of Ophthalmology.

[47]  P. Dell’Era,et al.  Examining new models for the study of autocrine and paracrine mechanisms of angiogenesis through FGF2-transfected endothelial and tumour cells. , 2000, Advances in experimental medicine and biology.