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Shu Kachi

Publications and source records attributed to Shu Kachi.

At least 19 recordsLinked to original sources
PubMed2007

Differential sensitivity of cones to iron-mediated oxidative damage.

PURPOSE: In this study, the hypothesis that increased intraocular levels of iron cause oxidative damage to the retina was tested. METHODS: Adult C57BL/6 mice were given an intravitreous injection of saline or 0.10, 0.25, or 0.50 mM FeSO(4). Scotopic electroretinograms (ERGs) were performed 3, 7, and 14 days after injection, and photopic ERGs were performed on day 14. Hydroethidine was used to identify superoxide radicals and lipid peroxidation was visualized by staining for hydroxynonenal (HNE). Retinal cell death was evaluated by TUNEL and measurement of inner nuclear layer (INL) and outer nuclear layer (ONL) thickness. Levels of rhodopsin and cone-opsin mRNA were measured by quantitative real time RT-PCR. Cone density was assessed by peanut agglutinin staining and confocal microscopy. RESULTS: Compared with retinas in saline-injected eyes, retinas from eyes injected with FeSO(4) showed greater fluorescence after intravenous injection of hydroethidine due to superoxide radicals in photoreceptors, greater photoreceptor staining for HNE, a marker of lipid peroxidation, and increased expression of Heme oxygenase 1, an indicator of oxidative stress. ERG b-wave amplitudes were reduced (photopic > scotopic) in FeSO(4)-injected eyes compared with those in saline-injected eyes. Numerous TUNEL-stained nuclei were seen along the outer border of the ONL, the location of cone cell nuclei, at 1 and 2 days after injection of FeSO(4). In FeSO(4)-injected eyes, the thickness of the ONL, but not the INL, was significantly reduced, and 17 days after injection, there were 3.8- and 2.6-fold reductions in the mRNAs for M-cone and S-cone opsin, respectively, whereas there was no significant difference in rhodopsin mRNA. Confocal microscopy of peanut agglutinin-stained sections showed dose-dependent FeSO(4)-induced cone drop out. CONCLUSIONS: Increased intraocular levels of FeSO(4) cause oxidative damage to photoreceptors with greater damage to cones than rods. This finding suggests that the oxidative defense system of cones differs from that of rods and other retinal cells, and that cones are more susceptible to damage from the type of oxidative stress imposed by iron.

Animals↗
PubMed2006

VMD2 promoter requires two proximal E-box sites for its activity in vivo and is regulated by the MITF-TFE family.

The retinal pigment epithelium (RPE) is crucial for the function and survival of retinal photoreceptors. VMD2 encodes bestrophin, an oligomeric chloride channel that is preferentially expressed in the RPE and, when mutated, causes Best macular dystrophy. Previously, we defined the VMD2 upstream region from -253 to +38 bp as being sufficient to direct RPE-specific expression in the eye, and we suggested microphthalmia-associated transcription factor (MITF) as a possible positive regulator. Here we show that in transgenic mice the -154 to +38 bp region is sufficient for RPE expression, and mutation of two E-boxes, 1 and 2, within this region leads to loss of promoter activity. A yeast one-hybrid screen using bait containing E-box 1 identified clones encoding MITF, TFE3, and TFEB, and chromatin immunoprecipitation with antibodies against these proteins enriched the VMD2 proximal promoter. Analysis using in vivo electroporation with constructs containing mutation of each E-box indicated that expression in native RPE requires both E-boxes, yet in vitro DNA binding studies suggested that MITF binds well to E-box 1 but only minimally to E-box 2. MITF knockdown by small interfering RNA (siRNA) in cell culture revealed a strong correlation between MITF and VMD2 mRNA levels. Sequential transfection of a luciferase construct with expression vectors following MITF siRNA revealed that TFE3 and TFEB can also transactivate the VMD2 promoter. Taken together, we suggest that VMD2 is regulated by the MITF-TFE family through two E-boxes, with E-box 1 required for a direct interaction of MITF-TFE factors and E-box 2 for binding of the as yet unidentified factor(s).

Animals↗
PubMed2006

Trans-scleral delivery of polyamine analogs for ocular neovascularization.

Periocular injections of the polyamine analog CGC-11144 three times a week causes regression of choroidal neovascularization. This regimen was selected to maximize chances of success for proof of concept, but is not ideal for clinical application. In this study we explored other regimens for periocular delivery of CGC-11144, and 2 other polyamine analogs, CGC-11047 and CGC-11093. A single periocular injection of 200 microg of CGC-11144, 2 mg of CGC-11047, or 1.5 mg of CGC-11093 caused significant suppression and regression of laser-induced choroidal neovascularization. An injection of 2 mg of CGC-11047 or 1.5 mg of CGC-11093 one or two weeks before, but not 3 weeks before, rupture of Bruch's membrane also caused significant suppression. Periocular injection of polyamine analogs also caused strong inhibition of retinal or subretinal neovascularization in mice with oxygen-induced ischemic retinopathy or Rhodopsin promoter/VEGF transgenic mice, respectively. These data suggest that periocular injection of one of 3 different polyamine analogs inhibits retinal or choroidal neovascularization and a single injection provides inhibitory activity for at least 2 to 3 weeks, which could provide the basis for a feasible treatment regimen for clinical trials.

Animals↗
PubMed2006

Adeno-associated virus (AAV) capsid genes isolated from rat and mouse liver genomic DNA define two new AAV species distantly related to AAV-5.

Using polymerase chain reactions and genome walking strategies, adeno-associated virus (AAV)-like capsid genes were isolated from rat and mouse liver genomic DNA, where they are present at <5 copies per cell. These genes define two new species of AAVs since their amino acid sequences are <60% identical to each other or to any other AAV capsid. They are most similar to the AAV-5 and goat AAV capsids. A recombinant vector with the mouse AAV capsid and a lacZ transgene (rAAV-mo.1 lacZ) was able to transduce rodent cell lines in vitro. However, it was not able to transduce eight human cell lines or primary human fibroblasts in vitro. It did not bind heparin and its ability to transduce cells in vitro was not inhibited by heparin, mucin, or sialic acid suggesting it uses a novel entry receptor. rAAV-mo.1 lacZ was 29 times more resistant to in vitro neutralization by pooled, purified human IgG than AAV-2. In vivo, rAAV-mo.1 lacZ efficiently transduced murine ocular cells after a subretinal injection. Intramuscular injection of a rAAV-mo.1 human factor IX (hFIX) vector into mice resulted in no detectable hFIX in plasma, but intravenous injection resulted in high plasma levels of hFIX, equivalent to that obtained from a rAAV-8 hFIX vector. Biodistribution analysis showed that rAAV-mo.1 primarily transduced liver after an intravenous injection. These AAV capsids may be useful for gene transfer in rodents.

Amino Acid Sequence↗
PubMed2006

Suppression and regression of choroidal neovascularization by systemic administration of an alpha5beta1 integrin antagonist.

Integrin alpha(5)beta(1) plays an important role in developmental angiogenesis, but its role in various types of pathologic neovascularization has not been completely defined. In this study, we found strong up-regulation of alpha(5)beta(1) in choroidal neovascularization. Implantation of an osmotic pump delivering 1.5 or 10 microg/h ( approximately 1.8 or 12 mg/kg/day) of 3-(2-{1-alkyl-5-[(pyridin-2-ylamino)-methyl]-pyrrolidin-3-yloxy}-acetylamino)-2-(alkylamino)-propionic acid (JSM6427), a selective alpha(5)beta(1) antagonist, caused significant suppression of choroidal neovascularization; the area of neovascularization was reduced by 33 to 40%. When an osmotic pump delivering 10 microg/h of JSM6427 was implanted 7 days after rupture of Bruch's membrane, there was terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining in vascular cells within the neovascularization and significant regression of the neovascularization over the next week. JSM6427 also induced apoptosis of cultured vascular endothelial cells. Fibronectin stimulates phosphorylation of extracellular signal-regulated kinase (ERK) in alpha(5)beta(1)-expressing cells that is blocked by JSM6427. These data suggest that alpha(5)beta(1) plays a role in the development and maintenance of choroidal neovascularization and provides a target for therapeutic intervention.

Administration, Cutaneous↗
PubMed2006

Intraocular injection of an aptamer that binds PDGF-B: a potential treatment for proliferative retinopathies.

Platelet-derived growth factor-B (PDGF-B) has been implicated in the pathogenesis of proliferative retinopathies and other scarring disorders in the eye. In this study, we sought to test the therapeutic potential of an aptamer that selectively binds PDGF-B, ARC126, and its PEGylated derivative, ARC127. Both ARC126 and ARC127 blocked PDGF-B-induced proliferation of cultured fibroblasts with an IC50 of 4 nM. Pharmacokinetic studies in rabbits showed similar peak vitreous concentrations of approximately 110 microM after intravitreous injection of 1 mg of either ARC126 or ARC127, but the terminal half-life was longer for ARC127 (98 versus 43 h). Efficacy was tested in rho/PDGF-B transgenic mice that express PDGF-B in photoreceptors and develop severe proliferative retinopathy resulting in retinal detachment. Compared to eyes injected with 20 microg of scrambled aptamer in which five of six developed detachments (three total and two partial), eyes injected with ARC126 (no detachment in five of six and one partial detachment), or ARC127 (no detachment in six of six) had significantly fewer retinal detachments. They also showed a significant reduction in epiretinal membrane formation. These data demonstrate that a single intravitreous injection of an aptamer that specifically binds PDGF-B is able to significantly reduce epiretinal membrane formation and retinal detachment in rho/PDGF-B mice. These striking effects in an aggressive model of proliferative retinopathy suggest that ARC126 and ARC127 should be considered for treatment of diseases in which PDGF-B has been implicated, including ischemic retinopathies such as proliferative diabetic retinopathy, proliferative vitreoretinopathy (PVR), and choroidal neovascularization.

3T3 Cells↗
PubMed2006

Recombinant non-collagenous domain of alpha2(IV) collagen causes involution of choroidal neovascularization by inducing apoptosis.

Vascular endothelial cells receive proangiogenic or antiangiogenic signals from components of extracellular matrix (ECM) depending upon the situation and many molecular signals can have opposite effects in different vascular beds. Tissue inhibitor of metalloproteinase 1 is antiangiogenic in several tissues, but promotes retinal neovascularization. When cleaved from native collagens, several of the non-collagenous domains (NC1) of basement membrane collagens have antiangiogenic effects in some tissues, but this is context dependent for the NC1 of the alpha 1 chain of collagen IV. It is critical to examine effects in several well-defined model systems before assuming that an ECM component is universally antiangiogenic. In this study, we examined the effects of a recombinant fragment of NC1 of the alpha 2 chain of type IV collagen (alpha2(IV)NC1) in a well-characterized model of ocular neovascularization. Intravitreous or periocular injections of alpha2(IV)NC1 caused selective apoptosis of endothelial cells participating in neovascularization resulting in suppression of neovascularization when the peptide was given prior to onset of new vessel sprouting. Importantly, when the peptide was given after neovascularization had already developed, it caused the new vessels to regress. This suggests that alpha2(IV)NC1, which has previously been shown to suppress tumor angiogenesis in xenograft models, is also a strong antiangiogenic agent in the choroid and is a therapeutic candidate for treatment of neovascular age-related macular degeneration.

Angiogenesis Inhibitors↗
PubMed2006

Reduction of p66Shc suppresses oxidative damage in retinal pigmented epithelial cells and retina.

The largest isoform of the Shc adapter protein, p66Shc, has been implicated in oxidative damage-induced apoptosis in vital organs, because mice deficient in p66Shc have a 30% increase in life span and are resistant to the lethal effects of systemically administered paraquat, a source of severe oxidative damage. In this study, we utilized siRNA directed against the CH2 domain of Shc, to reduce p66Shc, but not p52Shc nor p46Shc in retinal pigmented epithelial (RPE) cells. RPE cells deficient in p66Shc had reduced susceptibility to oxidative stress-induced apoptosis. Compared to control cells, those with reduced p66Shc had increased basal and oxidative stress-induced NF-kappaB transcriptional activity, increased levels of antioxidant enzymes, and less generation of reactive oxygen species when challenged with H(2)O(2). The increase in oxidative stress-induced NF-kappaB activity was mediated by activation of ERK. Compared to eyes injected with GFP siRNA, those injected with p66Shc siRNA showed less loss of retinal function as assessed by electroretinograms from paraquat-induced oxidative stress. These data suggest that p66Shc and molecular signals involved in its regulation provide therapeutic targets for retinal degenerations in which oxidative-damage plays a major role, including age-related macular degeneration and cone cell death in retinitis pigmentosa.

Adaptor Proteins, Signal Transducing↗
PubMed2005

Retinal degeneration from oxidative damage.

Paraquat, a herbicide that generates reactive oxygen species, has been used to probe the oxidative defense systems of lung. In this study, we investigated the effects of paraquat in the retina. There was no significant decline in electroretinogram (ERG) a- or b-wave amplitudes after intravitreous injection of 1 mul of 0.5 mM paraquat in C57BL/6 mice, but loss of ERG function occurred after injection of 0.75 or 1 mM paraquat. Histology in paraquat-injected eyes showed condensation of chromatin and thinning of the inner and outer nuclear layers indicating cell death, and terminal deoxynucleotidyl transferase-mediated duTP-biotinide end labeling demonstrated that one mechanism of cell death was apoptosis. Fluorescence in the retina and retinal pigmented epithelium after intraocular injection of paraquat followed by perfusion with hydroethidine indicated high levels of superoxide radicals, and oxidative damage was demonstrated by staining for acrolein and enzyme-linked immunosorbent assay for carbonyl adducts. Paraquat-induced damage to the outer nuclear layer was greater in BALB/c mice than in C57BL/6 mice, suggesting strain differences in the oxidative defense system of photoreceptors and/or other modifier genes. Intravitreous injection of paraquat provides a new model of oxidative damage-induced retinal degeneration that is likely to be useful for testing new antioxidant treatments.

Animals↗
PubMed2005

Vascular targeting of ocular neovascularization with a vascular endothelial growth factor121/gelonin chimeric protein.

Tumors provide an extremely abnormal microenvironment that stimulates neovascularization from surrounding vessels and causes altered gene expression within vascular cells. Up-regulation of vascular endothelial growth factor (VEGF) receptors has allowed selective destruction of tumor vessels by administration of a chimeric protein consisting of VEGF121 coupled to the toxin gelonin (VEGF/rGel). We sought to determine whether there is sufficient up-regulation of VEGF receptors in endothelial cells participating in ocular neovascularization to permit a similar strategy. After intravenous injection of 45 mg/kg VEGF/rGel, but not uncoupled recombinant gelonin (rGel), there was immunofluorescent staining for rGel within choroidal neovascularization in mice and regression of the neovascularization occurred, demonstrating successful vascular targeting via the systemic circulation. Intraocular injection of 5 ng of VEGF/rGel also caused significant regression of choroidal neovascularization and regression of retinal neovascularization in two models, transgenic mice with expression of VEGF in photoreceptors and mice with ischemic retinopathy, whereas injection of 5 ng of rGel had no effect. These data suggest that the strategy of vascular targeting can be applied to nonmalignant neovascular diseases and could serve as the basis of a new treatment to reduce established ocular neovascularization.

Animals↗
PubMed2005

Different effects of angiopoietin-2 in different vascular beds: new vessels are most sensitive.

In this study, we used double transgenic mice with inducible expression of angiopoietin-2 (Ang2) to investigate the role of Ang2 in the retinal and choroidal circulations and in three models of ocular neovascularization (NV). Mice with induced expression of Ang2 ubiquitously, or specifically in the retina, survived and appeared grossly normal. They also had normal-appearing retinal and choroidal circulations, demonstrating that high levels of Ang2 did not induce regression of mature retinal or choroidal vessels. When Ang2 expression was induced soon after birth, there was increased density of the deep capillary bed on postnatal day (P) 11 that returned to normal by P18, the time that retinal vascular development is usually completed. In mice with ischemic retinopathy, induction of Ang2 during the ischemic period resulted in a significant increase in retinal NV, but induction of Ang2 at a later time point when ischemia (and vascular endothelial growth factor [VEGF]) was less, hastened regression of NV. In triple transgenic mice that coexpressed VEGF and Ang2, the increased expression of Ang2 inhibited VEGF-induced NV in the retina. Increased expression of Ang2 also resulted in regression of choroidal neovascularization. These data suggest that ocular neovascularization, but not mature retinal or choroidal vessels, is sensitive to Ang2; a high Ang2/VEGF ratio promotes regression, while high Ang2 in the setting of hypoxia and/or concomitantly high Ang2 and VEGF stimulate neovascularization.

Angiopoietin-2↗
PubMed2005

Effect of plasmin on laminin and fibronectin during plasmin-assisted vitrectomy.

OBJECTIVE: To determine whether plasmin will cleave the laminin and fibronectin located at the vitreoretinal junction during plasmin-assisted vitrectomy. METHODS: Western blot analyses were performed with antilaminin or anti-fibronectin antibodies on the internal limiting membranes collected from patients with macular holes or cystoid macular edema who underwent vitrectomy with or without plasmin. The results were compared with the results of in vitro experiments in which commercially available laminin and fibronectin were exposed to commercially available plasmin. RESULTS: In all eyes treated with plasmin, a posterior vitreous detachment was not present before surgery but was created easily with a minimal suction of less than 100 mm Hg during vitrectomy. Western blot analyses showed that the laminin and fibronectin in the internal limiting membrane exposed to plasmin during vitrectomy were degraded to several fragments of lower molecular weights, including a fragment of approximately 13,000 Da for laminin and a fragment of approximately 30,000 Da for fibronectin. These lower-molecular-weight fragments also appeared in the in vitro experiments. CONCLUSION: The laminin and fibronectin at the vitreoretinal junction are degraded during plasmin-assisted vitrectomy. CLINICAL RELEVANCE: These findings provide evidence for the efficacy of using plasmin to create a posterior vitreous detachment during vitreoretinal surgery.

Basement Membrane↗
PubMed2005

Angiopoietin 1 prevents retinal detachment in an aggressive model of proliferative retinopathy, but has no effect on established neovascularization.

Vascular endothelial growth factor (VEGF) plays a central role in vasoproliferative diseases in the retina, however, other gene products modulate its effects. The angiopoietins are particularly important in this regard. Angiopoietin 2 (Ang2) collaborates with VEGF to stimulate neovascularization (NV) in some situations, but in other situations causes regression of NV. Ang2 also causes a transient increase in vascular density during retinal vascular development. In this study, we sought to determine if Ang1 has similar activities. The effects of Ang1 were tested in double transgenic mice with inducible expression of Ang1. Increased expression of Ang1 in the retina during retinal vascular development did not cause a detectable alteration in vascular density. Also, unlike Ang2, increased expression of Ang1 had no effect on established retinal or choroidal NV. However, when Ang1 expression was initiated simultaneously with that of VEGF, it strongly suppressed VEGF-induced NV and prevented retinal detachment. These data indicate that the timing of Ang1 expression is a critical determinate of its effects on VEGF-induced NV in the retina; it effectively blocks the initiation and progression of NV, but cannot reverse established NV or reduce leakage from NV. These data suggest that increased expression of Ang1 may be a good strategy for prophylaxis of retinal NV, but is unlikely to be effective as monotherapy of established NV.

Angiopoietin-1↗
PubMed2005

Periocular gene transfer of pigment epithelium-derived factor inhibits choroidal neovascularization in a human-sized eye.

Gene transfer provides a potential way to achieve sustained delivery of therapeutic proteins to the eye. Studies in rodents have suggested that periocular injection of adenoviral vectors containing expression cassettes for antiangiogenic proteins results in high intraocular levels of the proteins and suppression of choroidal neovascularization (CNV). However, the differences in size and scleral thickness between mouse and human eyes make it difficult to ascertain if periocular gene transfer is a feasible approach for treating human choroidal diseases. To address this issue, we tested the effect of periocular injection of an expression cassette for pigment epithelium-derived factor (PEDF) packaged in adenoviral vector (AdPEDF.11) in a CNV model in pigs, which have eyes that are very similar to humans in size and scleral thickness. Periocular injection of beta-galactosidase (AdLacZ.11) resulted in prominent transduction of periocular tissues, as was seen in mice. Periocular injection of AdPEDF.11 caused increased levels of PEDF in the choroid and significantly reduced the amount of CNV at rupture sites in Bruch's membrane. These data suggest that periocular gene transfer may be feasible for treatment of human choroidal diseases.

Adenoviridae↗
PubMed2005

Suppression and regression of choroidal neovascularization by polyamine analogues.

PURPOSE: Polyamine analogues inhibit tumor growth in vitro and in vivo, and oligoamines with a chain length of 10, 12, or 14 are particularly potent. This study was conducted to investigate the effect of the decamines CGC-11144 and CGC-11150 in a mouse model of choroidal neovascularization (CNV). METHODS: Mice with laser-induced rupture of Bruch's membrane were given intraperitoneal, intravitreous, or periocular injection of CGC-11144, CGC-11150, or vehicle, and after 14 days, they were perfused with fluorescein-labeled dextran, and the area of CNV was measured on choroidal flatmounts by image analysis. In some groups of mice, treatments were started 7 days after rupture of Bruch's membrane to determine the effect of the agent on established CNV. Electroretinograms (ERGs) were performed to assess the effects on retinal function, and histopathology was used to evaluate retinal structure. RESULTS: Intraperitoneal injection of 10 or 20 mg/kg CGC-11144 or CGC-11150 resulted in small but significant reductions in the area of CNV. Intravitreous injection of 20 microg CGC-11144 or CGC-11150 on days 0 and 7 after rupture of Bruch's membrane resulted in a approximately 40% reduction in the area of CNV, with a similar reduction after periocular injections of 0.2 mg CGC-11144 three times a week for 2 weeks. Both intravitreous and periocular delivery of CGC-11144 also caused significant regression of established CNV. Within 2 days of periocular injection of CGC-11144, there was apoptosis in CNV lesions, but not in normal blood vessels or other retinal cells. Periocular injections of d,l-alpha-difluoromethyl-ornithine (DFMO), which decreases polyamine levels by a different mechanism, also inhibited CNV. There was no decline in ERG amplitudes or abnormal retinal morphology after daily injections of 0.2 mg CGC-11144 for 2 weeks, but a single intravitreous injection compromised retinal structure and function. CONCLUSIONS: Periocular delivery of the polyamine analogues may be a useful approach for the treatment of CNV.

Animals↗
PubMed2005

Similar etiologies of functional visual loss observed in children and adults.

BACKGROUND AND PURPOSE: To describe four cases of functional visual loss which challenge the theory that its causes are different in children and adults (i.e., that financial gain is the primary cause in adults while in children it is an involuntary response to psychosocial problems). Rather, we will show a similar etiology of functional visual loss in children and adults. We also describe diagnostic testing and therapeutic approaches that are useful in both children and adults with functional visual loss. SUBJECTS AND METHODS: Two children (5 and 15 years old) and two adults (54 and 73 years old) with presumed functional visual loss and whose visual functions were assessed with verbal assurance, Starlight Test, Flicker Test, and trial glasses or contact lenses. RESULTS: Normal visual function was elicited in all four cases. In both pediatric patients we were able to elicit normal vision using verbal assurance and trial glasses or contact lenses. In both adult patients, we elicited dramatic improvements in vision with verbal assurance and discussion of the patients' psychosocial situation. CONCLUSION: Children and adults present with similar etiologies (psychosocial problems) of functional visual loss. In these cases we believe the children were motivated by their desire to wear glasses or contacts and the adults were involuntarily responding to psychosocial problems. These cases show that we cannot, as has been proposed, clearly categorize patients with functional visual loss based upon age.

Adolescent↗
PubMed2004

Increased expression of VEGF in retinal pigmented epithelial cells is not sufficient to cause choroidal neovascularization.

Increased expression of vascular endothelial cell growth factor (VEGF) in the retina is sufficient to stimulate sprouting of neovascularization from the deep capillary bed of the retina, but not the superficial retinal capillaries or the choriocapillaris. Coexpression of VEGF and angiopoietin 2 (Ang2) results in sprouting of neovascularization from superficial and deep retinal capillaries, but not the choriocapillaris. However, retina-derived VEGF and Ang2 may not reach the choriocapillaris, because of tight junctions between retinal pigmented epithelial (RPE) cells. To eliminate this possible confounding factor, we used the human vitelliform macular dystrophy 2 (VMD2) promoter, an RPE-specific promoter, combined with the tetracycline-inducible promoter system, to generate double transgenic mice with inducible expression of VEGF in RPE cells. Adult mice with increased expression of VEGF in RPE cells had normal retinas and choroids with no choroidal neovascularization (CNV), but when increased expression of VEGF in RPE cells was combined with subretinal injection of a gutless adenoviral vector containing an expression construct for Ang2 (AGVAng2), CNV consistently occurred. In contrast, triple transgenic mice with induced expression of Ang2 and VEGF in RPE cells, did not develop CNV. These data suggest that increased expression of VEGF and/or Ang2 in RPE cells is not sufficient to cause CNV unless it is combined with a subretinal injection of a gutless adenoviral vector, which is likely to perturb RPE cells. These data also suggest that the effects of angiogenic proteins may vary among vascular beds, even those that are closely related, and, therefore, generalizations should be avoided.

Angiopoietin-2↗