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Retinal neovascularization is a severe complication of proliferative diabetic retinopathy (PDR). MicroRNAs (miRNAs) are master regulators of gene expression that play an important role in retinal neovascularization. In this study, we show that miR-143-3p is significantly downregulated in the retina of a rat model of oxygen-induced retinopathy (OIR) by miRNA-sequencing. Intravitreal injection of synthetic miR-143 mimics significantly ameliorate retinal neovascularization in OIR rats. miR-143 is identified to be highly expressed in the neural retina particularly in the ganglion cell layer and retinal vasculature. In miR-143 treated cells, the functional evaluation showed a decrease in cell migration and delayed endothelial vessel-like tube remodeling. The multiomics analysis suggests that miR-143 negatively impacts endothelial cell activity through regulating cell-matrix adhesion and mediating hypoxia-inducible factor-1 signaling. We predict hub genes regulated by miR-143 that may be involved in mediating endothelial cell function by cytoHubba. We also demonstrate that the retinal neovascular membranes in patients with PDR principally consist of endothelial cells by CIBERSORTx. We then identify 2 hub genes, thrombospondin 1 and plasminogen activator inhibitor, direct targets of miR-143, that significantly altered in the PDR patients. These findings suggest that miR-143 appears to be essential for limiting endothelial cell-matrix adhesion, thus suppressing retinal neovascularization.

Gene therapies that chronically suppress vascular endothelial growth factor (VEGF) represent a new approach for managing retinal vascular leakage and neovascularization. However, constitutive suppression of VEGF in the eye may have deleterious side effects. Here, we developed a novel strategy to introduce Flt23k, a decoy receptor that binds intracellular VEGF, fused to the destabilizing domain (DD) of Escherichia coli dihydrofolate reductase (DHFR) into the retina. The expressed DHFR(DD)-Flt23k fusion protein is degraded unless "switched on" by administering a stabilizer; in this case, the antibiotic trimethoprim (TMP). Cells transfected with the DHFR(DD)-Flt23k construct expressed the fusion protein at levels correlated with the TMP dose. Stabilization of the DHFR(DD)-Flt23k fusion protein by TMP was able to inhibit intracellular VEGF in hypoxic cells. Intravitreal injection of self-complementary adeno-associated viral vector (scAAV)-DHFR(DD)-Flt23k and subsequent administration of TMP resulted in tunable suppression of ischemia-induced retinal neovascularization in a rat model of oxygen-induced retinopathy (OIR). Hence, our study suggests a promising novel approach for the treatment of retinal neovascularization. Schematic diagram of the tunable system utilizing the DHFR(DD)-Flt23k approach to reduce VEGF secretion. a The schematic shows normal VEGF secretion. b Without the ligand TMP, the DHFR(DD)-Flt23k protein is destabilized and degraded by the proteasome. c In the presence of the ligand TMP, DHFR(DD)-Flt23k is stabilized and sequestered in the ER, thereby conditionally inhibiting VEGF. Green lines indicate the intracellular and extracellular distributions of VEGF. Blue lines indicate proteasomal degradation of the DHFR(DD)-Flt23k protein. Orange lines indicate the uptake of cell-permeable TMP. TMP, trimethoprim; VEGF, vascular endothelial growth factor; ER, endoplasmic reticulum.

Background: Transplantation of gene transfected endothelial progenitor cells (EPCs) has provided novel methods for tumor neovascularization therapy but not for ocular disease therapy. This study aimed to investigate the efficacy of endostatin transfected EPCs in retinal neovascularization therapy., Results: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) showed the high expression of endostatin in endostatin-lentivirus-EPCs. The neovascularization leakage area and the number of preretinal neovascular cell nuclei were significantly decreased in the endostatin-lentivirus and endostatin-lentivirus-EPC groups, and the effects of these two treatments on inhibiting retinal neovascularization were almost the same. These two groups also showed the greater retinal distribution of endostatin. Intravitreal injections of endostatin-lentivirus-EPCs inhibited retinal neovascularization, vascular endothelial growth factor (VEGF) and CD31 expression, and increased endostatin expression in vivo. Endostatin-lentivirus-EPCs targeted and prevented pathologic retinal neovascularization., Conclusions: Gene-combined EPCs represent a potential new therapeutic agent for the treatment of neovascular eye diseases.

Angiogenesis-mediated neovascularization in the eye is usually associated with visual complications. Pathological angiogenesis is particularly prominent in the retina in the settings of proliferative diabetic retinopathy, in which it can lead to permanent loss of vision. In this study, by bioinformatics analyses, we provide evidence for elevated expression of actin-binding protein PFN1 (profilin1) in the retinal vascular endothelial cells (VECs) of individuals with proliferative diabetic retinopathy, findings further supported by gene expression analyses for PFN1 in experimentally induced abnormal retinal neovascularization in an oxygen-induced retinopathy murine model. We observed that in a conditional knockout mouse model, postnatal deletion of the Pfn1 gene in VECs leads to defects in tip cell activity (marked by impaired filopodial protrusions) and reduced vascular sprouting, resulting in hypovascularization during developmental angiogenesis in the retina. Consistent with these findings, an investigative small molecule compound targeting the PFN1-actin interaction reduced random motility, proliferation, and cord morphogenesis of retinal VECs in vitro and experimentally induced abnormal retinal neovascularization in vivo In summary, these findings provide the first direct in vivo evidence that PFN1 is required for formation of actin-based protrusive structures and developmental angiogenesis in the retina. The proof of concept of susceptibility of abnormal angiogenesis to small molecule intervention of PFN1-actin interaction reported here lays a conceptual foundation for targeting PFN1 as a possible strategy in angiogenesis-dependent retinal diseases., Competing Interests: Conflict of interest—The authors declare that they have no conflicts of interest with the contents of this article., (© 2020 Gau et al.)

This report describes a novel therapeutic technique called photo-mediated ultrasound therapy (PUT). PUT applies synchronized short pulse duration (nanosecond) laser and ultrasound burst on targeted tissue, offering high-precision localized treatment. PUT is based on controlled induction and promotion of micro-cavitation activity in the target tissue. PUT is able to safely and effectively treat retinal neovascularization in rabbits with persistent nonperfusion up to 4 weeks after PUT in the choroidal vasculature.Clinical Relevance- PUT can selectively remove retinal angiogenesis in clinically-relevant disease models in humansized eyes (rabbit) without damaging surrounding tissue.

Purpose: Recent studies have shown that inhibitors of the mechanistic target of rapamycin (mTOR) play important roles in proliferating endothelial cells within the retinal vasculature. Here we explore the effects of inhibiting mTOR as a potential gene therapeutic against pathological retinal angiogenesis in a rat model of oxygen-induced retinopathy (OIR)., Methods: Sprague-Dawley pups were used to generate the OIR model, with a recombinant adeno-associated virus expressing an shRNA (rAAV2-shmTOR-GFP) being administered via intravitreal injection on returning the rats to normoxia, with appropriate controls. Immunohistochemistry and TUNEL assays, as well as fluorescein angiography, were performed on transverse retinal sections and flat mounts, respectively, to determine the in vivo effects of mTOR inhibition., Results: Compared with normal control rats, as well as OIR model animals that were either untreated (20.95 ± 6.85), mock-treated (14.50 ± 2.47), or injected with a control short hairpin RNA (shRNA)-containing virus vector (16.64 ± 4.92), rAAV2-shmTOR-GFP (4.28 ± 2.86, P = 0.00103) treatment resulted in dramatically reduced neovascularization as a percentage of total retinal area. These results mirrored quantifications of retinal avascular area and vessel tortuosity, with rAAV2-shmTOR-GFP exhibiting significantly greater therapeutic efficacy than the other treatments. The virus vector was additionally shown to reduce inflammatory cell infiltration into retinal tissue and possess antiapoptotic properties, both these processes having been implicated in the pathophysiology of angiogenic retinal disorders., Conclusions: Taken together, these results demonstrate the strong promise of rAAV2-shmTOR-GFP as an effective and convenient gene therapy for the treatment of neovascular retinal diseases.

Purpose: To compare the efficacy of intravitreal aflibercept and laser photocoagulation in the treatment of retinopathy of prematurity (ROP)., Methods: The files of patients who were diagnosed as having type 1 ROP or aggressive posterior ROP (APROP) and treated with laser photocoagulation and 1 mg/0.025 mL of intravitreal aflibercept were retrospectively analyzed. The patients' birth weight, gestational age, detection week of the disease, zone, stage, presence of plus disease and rubeosis, regression of ROP, re-treatments administered during the follow-up, and spherical equivalent values obtained at the corrected sixth month were recorded., Results: The study included 27 eyes of 15 patients who underwent laser photocoagulation and 24 eyes of 12 patients who received intravitreal aflibercept. Retinal vascularization was in zone II in all eyes in the laser photocoagulation group and zone 1 in 22 eyes (91.7%) in the intravitreal aflibercept group (P < .05). In the laser photocoagulation group, 25 eyes (92.6%) had stage 3 ROP and 2 eyes (7.4%) had stage 2 ROP. In the intravitreal aflibercept group, 14 eyes (58.3%) had stage 3 ROP and 10 eyes (41.7%) had APROP (P < .05). Treatment was established at a postmenstrual age of 37.6 ± 2.5 weeks in the laser photocoagulation group and 34.2 ± 2.4 weeks in the intravitreal aflibercept group (P < .05). The regression rates after treatment were 92.6% and 100%, respectively (P > .05). In the intravitreal aflibercept group, laser photocoagulation was performed on 10 eyes (41.6%) during follow-up visits. Spherical equivalents were measured as +1.10 ± 2.30 and +1.50 ± 2.41 diopters, respectively (P < .05) at the corrected sixth month., Conclusions: Intravitreal aflibercept is an effective treatment for ROP. However, it requires more additional treatments than laser photocoagulation during the follow-up visits. [J Pediatr Ophthalmol Strabismus. 2020;57(1):54-60.]., (Copyright 2020, SLACK Incorporated.)

Purpose: To study the role of combined vitrectomy and intravitreal anti-vascular endothelial growth factor (VEGF) injection for stage 4 retinopathy of prematurity (ROP) with extensive neovascular proliferation., Methods: In a retrospective interventional study at a tertiary eye care center, 15 eyes (9 infants) with advanced stage 4 ROP underwent 25-gauge vitrectomy combined with intravitreal 0.625 mg of bevacizumab (n = 12) or 0.25 mg of ranibizumab (n = 3) injection and were followed up until 65 weeks' postconceptional age (PCA). The perinatal history, tractional retinal detachment (TRD) characteristics (zone, stage, and presence of "plus" disease), treatment details, and anatomical outcomes were reviewed. The main outcome measures were fibrovascular tissue and TRD regression and final macular status., Results: Mean gestational age and birth weight were 28.5 ± 1.2 weeks and 1,167 ± 185 g, respectively. Thirteen eyes had zone I disease and 2 eyes had zone II disease. Thirteen eyes were stage 4A and 2 eyes were stage 4B ROP. The morphology was aggressive posterior ROP in 10 eyes. The mean PCA at surgery was 37.8 ± 2.3 weeks. Lensectomy was also performed in 2 eyes. Rapid fibrovascular tissue regression was seen in 14 eyes within 2 weeks, followed by TRD regression and macular vascularization, although 2 eyes had macular pucker formation. Persistent vitreous bleeding was present in 1 eye, which needed lavage, and eventually the TRD regressed. Disease reactivation was noted in 1 eye at 5 weeks and was managed with repeat intravitreal anti-VEGF injection., Conclusions: Anti-VEGF treatment combined with vitrectomy leads to rapid disease regression in advanced stage 4 ROP with extensive neovascular proliferation. [J Pediatr Ophthalmol Strabismus. 2020;57(1):61-66.]., (Copyright 2020, SLACK Incorporated.)

Importance: The DRCR Retina Network Protocol S randomized clinical trial suggested that the mean visual acuity of eyes with proliferative diabetic retinopathy (PDR) treated with ranibizumab is not worse at 5 years than that of eyes treated with panretinal photocoagulation (PRP). Moreover, the ranibizumab group had fewer new cases of diabetic macular edema (DME) with vision loss or vitrectomy but had 4 times the number of injections and 3 times the number of visits. Although 2-year cost-effectiveness results of Protocol S were previously identified, incorporating 5-year data from Protocol S could alter the longer-term cost-effectiveness of the treatment strategies from the perspective of the health care system., Objective: To evaluate 5- and 10-year cost-effectiveness of therapy with ranibizumab, 0.5 mg, compared with PRP for treating PDR., Design, Setting, and Participants: A preplanned secondary analysis of the Protocol S randomized clinical trial using efficacy, safety, and resource utilization data through 5 years of follow-up for 213 adults diagnosed with PDR and simulating results through 10 years., Interventions: Intravitreous ranibizumab, 0.5 mg, at baseline and as frequently as every 4 weeks based on a structured retreatment protocol vs PRP at baseline for PDR; eyes in both groups could receive ranibizumab for concomitant DME with vision loss., Main Outcomes and Measures: Incremental cost-effectiveness ratios (ICERs) of ranibizumab therapy compared with PRP were evaluated for those with and without center-involved DME (CI-DME) and vision loss (Snellen equivalent, 20/32 or worse) at baseline., Results: The study included 213 adults with a mean (SD) age of 53 (12) years, of whom 92 (43%) were women and 155 (73%) were white. The ICER of the ranibizumab group compared with PRP for patients without CI-DME at baseline was $582 268 per quality-adjusted life-year (QALY) at 5 years and $742 202/QALY at 10 years. For patients with baseline CI-DME, ICERs were $65 576/QALY at 5 years and $63 930/QALY at 10 years., Conclusions and Relevance: This study suggests that during 5 to 10 years of treatment, ranibizumab, 0.5 mg, as given in the studied trial compared with PRP may be within the frequently cited range considered cost-effective in the United States for eyes presenting with PDR and vision-impairing CI-DME, but not for those with PDR but without vision-impairing CI-DME. Substantial reductions in anti-vascular endothelial growth factor cost may make the ranibizumab therapy cost-effective within this range even for patients without baseline CI-DME., Trial Registration: ClinicalTrials.gov identifier: NCT01489189.

Pathologic posterior neovascularization of eye is a major cause of irreversible vision loss and limitations of therapeutics to be successfully delivered to back of the eye has been a main obstacle for its effective treatment. Current pharmacological treatment using anti-VEGF agents being delivered intravitreally are effective but complicated due to anatomical and physiological barriers, as well as administration of high and frequent doses. With expanding horizons of nanotechnology, it can be possible to formulate promising nanoscale delivery system to improve penetration and sustained the release of therapeutic in posterior segment of the eye. Taking into consideration advances in the field of nanoscale delivery systems, this special report focuses on emerging strategies and their applications for treatment of posterior ocular neovascularization.

Retinopathy of prematurity (ROP) is a common retinal disease in preterm babies. To prolong the lives of preterm babies, high oxygen is provided to mimic the oxygen level in the intrauterine environment for postnatal organ development. However, hyperoxia-hypoxia induced pathological events occur when babies return to room air, leading to ROP with neuronal degeneration and vascular abnormality that affects retinal functions. With advances in neonatal intensive care, it is no longer uncommon for increased survival of very-low-birth-weight preterm infants, which, therefore, increased the incidence of ROP. ROP is now a major cause of preventable childhood blindness worldwide. Current proven treatment for ROP is limited to invasive retinal ablation, inherently destructive to the retina. The lack of pharmacological treatment for ROP creates a great need for effective and safe therapies in these developing infants. Therefore, it is essential to identify potential therapeutic agents that may have positive ROP outcomes, especially in preserving retinal functions. This review gives an overview of various agents in their efficacy in reducing retinal damages in cell culture tests, animal experiments and clinical studies. New perspectives along the neuroprotective pathways in the developing retina are also reviewed., Competing Interests: The authors declare no conflict of interest.

Purpose: To report the rate of new vessel (NV) regression after monthly injections of bevacizumab in laser-treated proliferative diabetic retinopathy (PDR) eyes with persistent neovascularization., Design: Prospective cohort study., Participants: Eyes with PDR with incomplete response to prior complete panretinal photocoagulation (PRP)., Methods: Ninety eyes of 80 patients with persistent PDR (pPDR) despite adequate PRP were prospectively followed on a monthly basis with anti-vascular endothelial growth factor (VEGF) injections when needed and stereo fundus images looking at the regression of NVs., Main Outcome Measures: Regression of NVs., Results: A total of 70 of 90 eyes (77.8%) had regression of the NV. Mean number of injections to reach quiescence was 9±3 for pPDR in the high-risk characteristics (HRC) group (80 eyes) and 3±1 for PDR in the group without HRC (10 eyes) (P < 0.001). All patients with PDR without HRC responded to the adjuvant therapy, whereas 75.0% of the eyes with PDR with HRC responded. Eyes with initial retinal neovascularization all responded to the adjuvant treatment. Eyes without a vitreous hemorrhage at study entry were more likely to respond (odds ratio, 5.43; 95% confidence interval, 1.37-21.44; P < 0.01). Therapy was judged unsuccessful because of the continuous growth of the NV despite treatment (3 eyes), the development of traction (5 eyes), and the development of a dense vitreous hemorrhage (6 eyes)., Conclusions: Anti-VEGF rescue therapy has a potential role in select cases of laser-treated PDR with persistent NVs and no evidence of traction to achieve regression of neovessels., (Copyright © 2019 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Objective: To investigate the treatment of retinopathy of incontinentia pigmenti by anti-vascular endothelial growth factor. Methods: Retrospective study of 5 patients(8 eyes) diagnosed retinopathy of incontinentia pigmenti from 2005 to 2017, including 0 males and 5 females (8 eyes involved) with an average age of 2.4 months(range, 1-5 months). Medical history and family history were recorded in detail for all children. We did the examination of anterior segment of the eyeball, vitreous body,fundus and intraocular pressure for the 5 patients(8eyes).What's more,wo also took pictures for fundus with the machine of Retcam. Fundus fluorescence angiography (FFA) was performed in 2 patients(4 eyes). Different surgical methods were selected according to the specific conditions of the eye and postoperative were observed. Results: At the time of initial diagnosis, preretinal hemorrhage did not affect the macular region in 3 cases (5 eyes), pre retinal hemorrhage affected the macular region in 1 case(1 eye), the retinal neovascularization in 3 cases(5 eyes), the retinal detachment in 2 cases(2 eyes), and nonvascular zone of peripheral retinal in 5cases(8 eyes). Treatment and drug selection: 3 cases(5 eyes) were treated with injection anti-VEGF drug into vitreous body cavity, 1 case(1 eye) was treated with injection anti-VEGF drug into vitreous body cavity plus laser photocoagulation, 1 case(1 eye) was treated with anti-VEGF drugs plus vitrectomy. 1 case(1 eye) was treated with anti-VEGF drugs plus retinal cryotherapy and sclera bucking. In patients of injection anti-VEGF drug into vitreous body cavity, 2 cases(3 eyes) were given a single dose and 1 case (2 eyes) was given a repeated dose. Drug selection: 4 cases(6 eyes) ranibizumab injection (injection dose 0.025 ml), 1 case (2 eyes)conbercept injection (injection dose 0.025 ml). To follow-up date, etina was flat in 4 patients (7 eyes), epiretinal membrane in 2 patients(2 eyes), retinal detachment in 1 patient(1 eye). Conclusions: The efficacy of anti-vascular endothelial growth factor in the treatment of retinopathy of incontinentia pigmenti was prelininarily confimed.However,the optimal use timing,dosage,local and systemic safety issues were needed to be further studied. (Chin J Ophthalmol, 2019, 55:294-301) .

Purpose: Submacular haemorrhage (SMH) is a cause of severe visual loss in neovascular age-related macular degeneration (nAMD). The incidence is uncertain and furthermore there is no widely used classification system nor agreed best practice. The aim of this national surveillance study was to identify the incidence, presenting features and clinical course of new fovea-involving submacular haemorrhage associated with nAMD., Methods: A questionnaire was sent monthly to every ophthalmic specialist in Scotland over a 12-month period asking them to report all newly presenting patients with acute SMH secondary to nAMD of at least two disc diameters (DDs) in greatest linear diameter. A follow-up questionnaire was sent 6 months after initial presentation. Cases related to other causes were excluded., Results: Twenty-nine cases were reported giving an incidence of 5.4 per million per annum (range 2-15). The mean age was 83 years (range 66-96) and females accounted for 17/29 (59%). Fifteen of the 29 cases (52%) had a past history of AMD, of which 7 had nAMD. Nineteen of the 29 cases (66%) presented within 7 days of onset and the majority had SMH of < 11 DD (20/29, 69%). Treatment options comprised the following: observation (n = 6, 21%), anti-VEGF alone (n = 6, 21%) or vitrectomy with co-application of tissue plasminogen activator (TPA), anti-VEGF and gas (n = 17, 58%). The vitrectomy group experienced the greatest change in vision from logMAR 1.89-1.50 (p = 0.374). Four of 20 (20%) cases with 6 months follow-up suffered a re-bleed at a mean time of 96 days., Conclusions: The incidence, clinical features and course of a consecutive national cohort of patients with SMH secondary to nAMD are presented.

Purpose: To compare anatomic and functional outcomes in eyes with proliferative diabetic retinopathy (PDR) that were lost to follow-up (LTFU) for more than 6 months after treatment with either intravitreal injection (IVI) of anti-vascular endothelial growth factor (VEGF) agents or panretinal photocoagulation (PRP)., Design: Retrospective cohort study., Participants: Fifty-nine patients who were LTFU immediately after treatment for more than 6 months between September 2013 and September 2016., Methods: Patients with eyes receiving either intravitreal anti-VEGF treatment or PRP with the next follow-up visit occurring more than 6 months after treatment were identified. Visual acuity (VA) and anatomic outcomes at the visit before being LTFU, the return visit, the 6-month visit after return, the 12-month visit after return, and the final visit were gathered and compared between the 2 treatment groups., Main Outcomes Measures: Visual acuity and anatomic outcomes., Results: Seventy-six eyes of 59 patients were included in the study, of which 30 received IVI with anti-VEGF and 46 received PRP. In the anti-VEGF group, mean VA worsened significantly when comparing the visit before being LTFU (0.43±0.38 logarithm of the minimum angle of resolution [logMAR]) with the return visit (0.97±0.80 logMAR; P = 0.001) as well as with the final visit (0.92±0.94 logMAR; P = 0.01). In the PRP group, mean VA worsened significantly when comparing the visit before being LTFU (0.42±0.34 logMAR) with the return visit (0.62±0.64 logMAR; P = 0.03). However, no significant difference was observed at the final visit (0.46±0.47 logMAR; P = 0.38). There was a significantly greater number of eyes with tractional retinal detachment in the IVI group compared with the PRP group at the final visit (10 vs. 1, respectively; P = 0.005). There was a significantly greater incidence of neovascularization of the iris in the IVI arm compared with the PRP arm at the final visit (4 vs. 0, respectively; P = 0.02)., Conclusions: Eyes with PDR that received only intravitreal anti-VEGF demonstrated worse anatomic and functional outcomes after being LTFU compared with eyes that received PRP. Given the potential sequelae of being LTFU, the choice of treatment for PDR must be considered carefully., (Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Inhibition of vascular endothelial growth factor (VEGF) in retinopathy of prematurity (ROP) raises concerns for premature infants because VEGF is essential for retinovascular development as well as neuronal and glial health. This study tested the hypothesis that endothelial cell-specific knockdown of VEGF receptor 2 (VEGFR2), or downstream STAT3, would inhibit VEGF-induced retinopathy without delaying physiologic retinal vascular development. We developed an endothelial cell-specific lentiviral vector that delivered shRNAs to VEGFR2 or STAT3 and a green fluorescent protein reporter under control of the VE-cadherin promoter. The specificity and efficacy of the lentiviral vector-driven shRNAs were validated in vitro and in vivo. In the rat oxygen-induced retinopathy model highly representative of human ROP, the effects of endothelial cell knockdown of VEGFR2 or STAT3 were determined on intravitreal neovascularization (IVNV), physiologic retinal vascular development [assessed as area of peripheral avascular/total retina (AVA)], retinal structure, and retinal function. Targeted knockdown of VEGFR2 or STAT3 specifically in retinal endothelial cells by subretinal injection of lentiviral vectors into postnatal day 8 rat pup eyes efficiently inhibited IVNV, and knockdown of VEGFR2 also reduced AVA and increased retinal thickness without altering retinal function. Taken together, our results support specific knockdown of VEGFR2 in retinal endothelial cells as a novel therapeutic method to treat retinopathy.

Purpose: To compare retinal function changes in eyes with proliferative diabetic retinopathy (PDR) after intravitreal ranibizumab (IVR), combined or not with conventional (ETDRS) or multispot laser panretinal (PASCAL) photocoagulation (PRP)., Methods: This study included laser-naive PDR patients that required PRP. Eyes were randomly and prospectively assigned to receive IVR or IVR combined with PASCAL or EDTRS. PRP was performed at baseline in 1 (PASCAL) or 2 (ETDRS) sessions. In eyes with macular edema, macular short pulse grid laser was associated with IVR at baseline and IVR was repeated monthly or quarterly if neovascularization was detected on angiography. Comprehensive ophthalmological evaluations, including SD-OCT, were performed at baseline and every 4 weeks after treatment. Full-field electroretinography (ERG: extended ISCEV standard) was performed at baseline and at 12, 24 and 48 weeks., Results: IVR = 13, PASCAL = 15 and ETDRS = 15 eyes finished 48-week follow-up. There was a statistically significant BCVA improvement of 0.1-0.3 logMAR in all groups, and fluorescein angiography leakage area (FLA) reduced in 56%, 73%, and 73% from baseline for ETDRS, IVR and PASCAL, respectively, up to 48 weeks without significant differences between groups (p > 0.05). A significant a- and b-wave amplitudes reduction was observed for dark- and light-adapted ERG for ETDRS and PASCAL, but only minor dark-adapted b-wave reduction was found for IVR, up to 48 weeks. As an example, at week 48, combined response b-wave amplitude reduced in 181.5 ± 31.4 µV, 128.0 ± 27.9 µV and 82.4 ± 15.2 µV for ETDRS, PASCAL and IVR (p < 0.05 each group), respectively. No significant difference was observed between ETDRS and PASCAL for any ERG parameter., Conclusions: IVR combined with single or multiple spot PRP causes similar retinal function impairment during 48 weeks of observation, while IVR alone seems to be similarly effective controlling FLA without changing retinal function.

Purpose: Comparison of the efficacy of ranibizumab (RBZ) 0.5 mg intravitreal injections plus panretinal photocoagulation (PRP) versus PRP alone in the regression of the neovascularization (NV) area in subjects with high-risk proliferative diabetic retinopathy (HR-PDR) over a 12-month period., Design: Prospective, randomized, multicenter, open-label, phase II/III study., Participants: Eighty-seven participants (aged ≥18 years) with type 1/2 diabetes and HR-PDR (mean age, 55.2 years; 37% were female)., Methods: Participants were randomized (1:1) to receive RBZ+PRP (n = 41) or PRP monotherapy (n = 46). The RBZ+PRP group received 3 monthly RBZ injections along with standard PRP. The PRP monotherapy group received standard PRP between day 1 and month 2; thereafter, re-treatments in both groups were at the investigators' discretion., Main Outcome Measures: The primary outcome was regression of NV total, on the disc (NVD) plus elsewhere (NVE), defined as any decrease in the area of NV from the baseline to month 12. Secondary outcomes included best-corrected visual acuity (BCVA) changes from baseline to month 12, time to complete NV regression, recurrence of NV, macular retinal thickness changes from baseline to month 12, need for treatment for diabetic macular edema, need for vitrectomy because of occurrence of vitreous hemorrhage, tractional retinal detachment or other complications of DR, and adverse events (AEs) related to treatments., Results: Seventy-seven participants (88.5%) completed the study. Overall baseline demographics were similar for both groups, except for age. At month 12, 92.7% of participants in the RBZ+PRP group presented NV total reduction versus 70.5% of the PRP monotherapy participants (P = 0.009). The number of participants with NVD and NVE reductions was higher with RBZ+PRP (93.3% and 91.4%, respectively) versus PRP (68.8% and 73.7%, respectively), significant only for NVE (P = 0.048). Complete NV total regression was observed in 43.9% in the RBZ+PRP group versus 25.0% in the PRP monotherapy group (P = 0.066). At month 12, the mean BCVA was 75.2 letters (20/32) in the RBZ+PRP group versus 69.2 letters (20/40) in the PRP monotherapy group (P = 0.104). In the RBZ+PRP group, the mean number of PRP treatments over month 12 was 3.5±1.3, whereas in the PRP monotherapy group, it was 4.6±1.5 (P = 0.001). No deaths or unexpected AEs were reported., Conclusions: Treatment with RBZ+PRP was more effective than PRP monotherapy for NV regression in HR-PDR participants over 12 months., (Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Sustained suppression of VEGF is needed in many patients with neovascular age-related macular degeneration (NVAMD), and gene transfer of a VEGF-neutralizing protein is a promising approach to achieve it. Initial clinical trials testing this approach have shown encouraging signals, but evidence of robust transgene expression and consistent antiangiogenic and antipermeability activity has been lacking. In this study, we demonstrate expression of an anti-human VEGF antibody fragment (antiVEGFfab) after subretinal injection of AAV8-antiVEGFfab. In transgenic mice expressing human VEGF in retina (rho/VEGF mice), a model of type 3 choroidal neovascularization (NV), eyes injected with ≥1 × 10 7 gene copies (GC) of AAV8-antiVEGFfab had significantly less mean area of NV than null vector-injected eyes. A dose-dependent response was observed with modest reduction of NV with ≤3 × 10 7 , >50% reduction with ≥1 × 10 8 GC and almost complete elimination of NV with 3 × 10 9 or 1 × 10 10 GC. In Tet/opsin/VEGF mice, in which doxycycline-induced high expression of VEGF leads to severe vascular leakage and exudative retinal detachment (RD), reduction of total RD by 70%-80% occurred with 3 × 10 9 or 1 × 10 10 GC of AAV8-antiVEGFfab, an effect that was sustained for at least a month. These data strongly support initiating clinical trials testing subretinal injection of AAV8-antiVEGFfab in patients with NVAMD., (Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)

Generation of lentivirus (LV)-based vectors holding multiple gene cassettes for coexpression of several therapeutic factors provides potent tools in both gene delivery studies as well as in gene therapy. Here we describe the development of such multigenic LV gene delivery vectors enabling cell-specific coexpression of antiangiogenic microRNA (miRNA) and protein factors and, if preferred, a fluorescent reporter, from RNApol(II)-driven expression cassettes orientated in a back-to-back fashion. This configuration may contribute to the development of new combination therapies for amelioration of diseases involving intraocular neovascularization including exudative age-related macular degeneration (AMD).

Neoangiogenesis is the main pathogenic event involved in a variety of retinal diseases. It has been recently demonstrated that inhibiting the urokinase-type plasminogen activator receptor (uPAR) results in reduced angiogenesis in a mouse model of oxygen-induced retinopathy (OIR), establishing uPAR as a therapeutic target in proliferative retinopathies. Here, we evaluated in cultured human retinal endothelial cells (HRECs) and in OIR mice the potential of a specific antisense oligodeoxyribonucleotide (ASO) in blocking the synthesis of uPAR and in providing antiangiogenic effects. uPAR expression in HRECs was inhibited by lipofection with the phosphorotioated 5'-CGGCGGGTGACCCATGTG-3' ASO-uPAR, complementary to the initial translation site of uPAR mRNA. Inhibition of uPAR expression via ASO-uPAR was evaluated in HRECs by analyzing VEGF-induced tube formation and migration. In addition, the well-established and reproducible murine OIR model was used to induce retinal neovascularization in vivo. OIR mice were injected intraperitoneally with ASO-uPAR and retinopathy was evaluated considering the extent of the avascular area in the central retina and neovascular tuft formation. The ASO-uPAR specifically decreased uPAR mRNA and protein levels in HRECs and mitigated VEGF-induced tube formation and cell migration. Noteworthy, in OIR mice ASO-uPAR administration reduced both the avascular area and the formation of neovascular tufts. In conclusion, although the extrapolation of these experimental findings to the clinic is not straightforward, ASO-uPAR may be considered a potential therapeutic tool for treatment of proliferative retinal diseases., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Despite the advance in medical technology, diabetic retinopathy (DR) is still an intractable disease which leads to the damage of retinal cells and finally the visual loss. Impairment of retinal vascular barrier triggered by an admixture of multiple inflammatory cytokines is a core of pathophysiology of DR. Therefore, the molecules involved commonly in multiple cytokines-induced impairment of vascular barrier would be the targets of curative treatment of DR. Here, we demonstrate that basigin, a transmembrane molecule expressed in neural barrier-forming endothelial cells, is the molecule essential for vascular barrier impairment which is shared by various triggers including VEGF, TNFα and IL-1β. In vitro data with neural microvascular endothelial cells indicated that stimulation with cytokines decreases the levels of claudin-5 in cell membranes and consequently impairs the barrier function in a manner dependent on the interaction of claudin-5 with basigin and caveolin-1. In addition, the increased vascular permeability in retinas of streptozotocin-induced diabetic mice was shown to be clearly normalized by intravitreous injection of siRNAs specific for basigin. This study has highlighted basigin as a common essential molecule for various stimuli-induced impairment of retinal vascular barrier, which can be a target for strategies to establish a curative treatment of DR.

Retinal neovascularization (NV) due to retinal ischemia is one of the major causes of vision reduction in patients with different types of retinal diseases although anti-vascular endothelial growth factor (anti-VEGF) therapy can partially reduce the size of the retinal NV. We recently reported that periostin plays an important role in the development of NV and the formation of preretinal fibrovascular membranes, but the role of the splice variants of periostin on retinal NV has not been determined. We examined the expressions of periostin splice variants in the ischemic retinas of a mouse model of oxygen-induced retinal NV. We also studied the function of periostin splice variants on retinal NV using periostin knock out mice, and the effects of anti-periostin antibodies on retinal NV. Our results showed that the expressions of the periostin splice variants were increased in ischemic retinas. The degree of increase of periostin lacking exon 17 was the highest among the periostin splice variants examined. Both genetic ablation of periostin exons 17 and 21 and antibodies for periostin exons 17 and 21 affected preretinal pathological NV. Inhibition of exon 17 of periostin had the greatest effect in reducing preretinal pathological NV. These findings suggest a causal link between periostin splice variants and retinal NV, and an intravitreal injection of antibody for exon 17 and exon 21 of periostin should be considered to inhibit preretinal pathological NV., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Purpose: To compare choroidal thickness (CT) and retinal thickness (RT) between eyes with proliferative diabetic retinopathy treated with panretinal photocoagulation (PRP) or PRP with intravitreal bevacizumab (PRP + IVB)., Methods: Thirty-three patients with proliferative diabetic retinopathy were randomized to have one eye treated with PRP and the other with PRP + IVB. Change in CT was compared with baseline using enhanced depth imaging-optical coherence tomography at baseline and Months 1, 3, 6, and 10 after treatment. Change in RT was similarly assessed using spectral domain optical coherence tomography. Changes in both CT and RT were assessed in all nine macular areas as defined by Early Treatment Diabetic Retinopathy Study subfields., Results: The PRP + IVB group had a significant decrease in subfoveal CT at 3 and 10 months (323.9 ± 62 μm at baseline vs. 320.7 ± 64.8 μm at Month 3 [P = 0.024] and 304.7 ± 65.6 μm at Month 10 [P = 0.003]). Subfoveal CT significantly decreased at 10 months compared with baseline in the PRP group (320.8 ± 57.7 at baseline to 297 ± 66.3 μm at 10 months, P = 0.01). Subfoveal CT was not significantly different between the 2 groups at 10 months. The best-corrected visual acuity did not change after treatment in the two groups, and there was no correlation between BCVA and CT changes (r = 0.222, P = 0.37 in the PRP group and r = 0.387, P = 0.12 in the PRP + IVB group). Significant increases in RT were seen in the PRP + IVB group at 6 months and in the PRP group at Months 1, 3, 6, and 10. A correlation between changes in CT and RT was only seen in the PRP group at 10 months after treatment., Conclusion: Eyes with proliferative diabetic retinopathy treated with PRP + IVB and PRP both had significant reduction in CT at 10 months; however, the eyes that were also treated with IVB also underwent an earlier but transient reduction at 3 months. Patients treated with IVB underwent less increase in RT.

Purpose: To compare patient-centered outcomes in patients with proliferative diabetic retinopathy (PDR) treated with ranibizumab vs panretinal photocoagulation (PRP)., Design: Randomized clinical trial., Methods: Setting: Multicenter (55 U.S. sites)., Patient Population: Total of 216 adults with 1 study eye out of 305 adults (excluding participants with 2 study eyes, because each eye received a different treatment) with PDR, visual acuity 20/320 or better, no history of PRP., Intervention: Ranibizumab (0.5 mg/0.05 mL) vs PRP., Main Outcome Measures: Change from baseline to 2 years in composite and prespecified subscale scores from the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25), University of Alabama Low Luminance Questionnaire (UAB-LLQ), and Work Productivity and Activity Impairment Questionnaire (WPAIQ)., Results: For the NEI VFQ-25 and UAB-LLQ composite scores, ranibizumab-PRP treatment group differences (95% CI) were +4.0 (-0.2, +8.3, P = .06) and +1.8 (-3.5, +7.1, P = 0.51) at 1 year, and +2.9 (-1.5, +7.2, P = .20) and +2.3 (-2.9, +7.5, P = .37) at 2 years, respectively. Work productivity loss measured with the WPAIQ was 15.6% less with ranibizumab (-26.3%, -4.8%, P = .005) at 1 year and 2.9% (-12.2%, +6.4%, P = .54) at 2 years. Eighty-three ranibizumab participants (97%) were 20/40 or better in at least 1 eye (visual acuity requirement to qualify for an unrestricted driver's license in many states) at 2 years compared with 82 PRP participants (87%, adjusted risk ratio = 1.1, 95% CI: 1.0, 1.2, P = .005)., Conclusions: Though differences in some work productivity and driving-related outcomes favored ranibizumab over PRP, no differences between treatment regimens for PDR were identified for most of the other patient-centered outcomes considered., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The authors describe two premature infants who developed stage 3, zone I retinopathy of prematurity (ROP) with plus disease in both eyes, despite limited exposure to supra-ambient oxygen. Both infants received noninvasive respiratory support for several weeks. Both cases are notable because the ROP was more posterior and aggressive than is typical for the gestational ages or birth weights. These cases are insufficient to make definitive conclusions regarding the factors that cause ROP. Further investigation is required to determine if there is an association between the use of non-invasive respiratory support, even in the absence of supra-ambient oxygen, and severe ROP development. [J Pediatr Ophthalmol Strabismus. 2016;53:e47-e50.]., (Copyright 2016, SLACK Incorporated.)

Purpose: To evaluate the role, safety, and effectiveness of intravitreal conbercept (KH902) injections as an adjunct to vitrectomy in the management of severe proliferative diabetic retinopathy., Methods: A randomized controlled trial was performed on 36 eyes of 36 patients affected by vitreous hemorrhage and tractional retinal detachment, which occurred as a consequence of active proliferative diabetic retinopathy. The patients were randomly assigned to two groups. The patients in one of the groups received an intravitreal injection of conbercept in the inferior temporal sector 4 mm from the sclerocorneal limbus with a sterile technique 1 week before vitrectomy., Results: In the group without conbercept, intraoperative bleeding occurred in 14 patients (77.8%), and in five of these cases, bleeding was significant. The use of endodiathermy was necessary in 8 patients (44.4%). In 3 patients (16.6%), iatrogenic retinal breaks occurred, and in 1 patient (5.5%), a relaxing retinotomy was performed. Endotamponade with silicone oil was performed in 12 patients (66.6%). In the group treated with conbercept, intraoperative bleeding occurred in 2 cases (11.1%). The use of endodiathermy was necessary in 1 patient (5.5%). No patients experienced iatrogenic breaks or relaxing retinotomy during the surgery. Endotamponade with silicone oil was performed in 2 patients (11.1%)., Conclusion: Preoperative intravitreal injection of conbercept could reduce the chances of intraoperative bleeding, which are beneficial in the management of proliferative diabetic retinopathy.

Abnormal angiogenesis is a primary cause of many eye diseases, including diabetic retinopathy, age-related macular degeneration, and retinopathy of prematurity. Mesenchymal stem cells (MSCs) are currently being investigated as a treatment for several such retinal diseases based on their neuroprotective and angiogenic potentials. In this study, we evaluated the role of systemically injected human placental amniotic membrane-derived MSCs (AMSCs) on pathological neovascularization of proliferative retinopathy. We determined that AMSCs secrete higher levels of transforming growth factor-β (TGF-β1) than other MSCs, and the secreted TGF-β1 directly suppresses the proliferation of endothelial cells under pathological conditions in vitro. Moreover, in a mouse model of oxygen-induced retinopathy, intraperitoneally injected AMSCs migrated into the retina and suppressed excessive neovascularization of the vasculature via expression of TGF-β1, and the antineovascular effect of AMSCs was blocked by treatment with TGF-β1 siRNA. These findings are the first to demonstrate that TGF-β1 secreted from AMSCs is one of the key factors to suppress retinal neovascularization in proliferative retinopathy and further elucidate the therapeutic function of AMSCs for the treatment of retinal neovascular diseases.

Age-related macular degeneration (AMD) is the leading cause of blindness among the elderly in developed countries. AMD is classified as either neovascular (NV-AMD) or non-neovascular (NNV-AMD). Cumulative damage to the retinal pigment epithelium, Bruch's membrane, and choriocapillaris leads to dysfunction and loss of RPE cells. This causes degeneration of the overlying photoreceptors and consequential vision loss in advanced NNV-AMD (Geographic Atrophy). In NV-AMD, abnormal growth of capillaries under the retina and RPE, which leads to hemorrhage and fluid leakage, is the main cause of photoreceptor damage. Although a number of drugs (e.g., anti-VEGF) are in use for NV-AMD, there is currently no treatment for advanced NNV-AMD. However, replacing dead or dysfunctional RPE with healthy RPE has been shown to rescue dying photoreceptors and improve vision in animal models of retinal degeneration and possibly in AMD patients. Differentiation of RPE from human embryonic stem cells (hESC-RPE) and from induced pluripotent stem cells (iPSC-RPE) has created a potentially unlimited source for replacing dead or dying RPE. Such cells have been shown to incorporate into the degenerating retina and result in anatomic and functional improvement. However, major ethical, regulatory, safety, and technical challenges have yet to be overcome before stem cell-based therapies can be used in standard treatments. This review outlines the current knowledge surrounding the application of hESC-RPE and iPSC-RPE in AMD. Following an introduction on the pathogenesis and available treatments of AMD, methods to generate stem cell-derived RPE, immune reaction against such cells, and approaches to deliver desired cells into the eye will be explored along with broader issues of efficacy and safety. Lastly, strategies to improve these stem cell-based treatments will be discussed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Purpose: The purpose of this study was to investigate whether ultrasound-targeted cationic microbubble destruction could effectively deliver endostatin-green fluorescent protein (ES-GFP) plasmids to human retinal vascular endothelial cells (HRECs)., Methods: Cationic microbubbles (CMBs) were prepared and then compared with neutral microbubbles (NMBs) and liposomes. First, the two types of microbubbles were characterized in terms of size and zeta potential. The cell viability of the HRECs was measured using the 3-(4,5-dimthylthiazol-2-yl)-2,5 diphenyl-tetrazolium bromide (MTT) assay. The transcription and expression of endostatin, VEGF, Bcl-2, and Bcl-xl were measured via quantitative real-time PCR (qPCR) and western blotting, respectively., Results: CMBs differed significantly from NMBs in terms of the zeta potential, but no differences in size were detected. Following ultrasound-targeted microbubble destruction (UTMD)-mediated gene therapy, the transcription and expression of endostatin were highest in the CMB group (p<0.05), while the transcription and expression of VEGF, Bcl-2, and Bcl-xl were lowest compared with the other groups. Moreover, the inhibition of HREC growth was enhanced following treatment with CMBs compared with NMBs or liposomes in vitro (p<0.01)., Conclusions: This study demonstrated that ultrasound-mediated cationic microbubbles could enhance the transfection efficiency of ES-GFP, which had obvious impacts on the inhibition of the growth process of HRECs in vitro. These results suggest that the combination of UTMD and ES-GFP compounds might be a useful tool for gene therapy targeting retinal neovascularization.

The diagnosis of RAP is similar with the diagnosis of the AMD, but PED, exudate and superficial hemorrhages are more common in RAP. A 75-year-old male presented himself at the Ophthalmology Department of the Emergency County Hospital in Craiova in January 2015, with a 4 months history of vision loss. In his right eye the visual acuity was 4/50 eye non-optical correctable and 5/5 with optical correction in the left eye. According to the FA and OCT that were performed in both eyes, in the right eye was found intraretinal neovascularization and sub and intraretinal fluid. A normal aspect was found in the left eye. After the investigations we decided to start the treatment consisting in one single intravitreal injection with Triamcinolone Acetonide (IVTA) in the right eye. The VA improved 1 week after the treatment from 4/50 to 5/30. In comparison with the improved VA, the macular edema gradually resorbed 1 month after the IVTA injection. In spite of the late presentation of the patient in the Ophthalmology Department, the VA and OCT outcome after a single dose of IVTA injection was very good.

Purpose: To describe the structural characteristics of retinal angiomatous proliferation and chorioretinal anastomosis in childhood Coats disease and redefine the previously described macular fibrosis., Methods: Prospective observational case series of consecutive patients with Coats disease examined over a 1-year study period. Multimodal imaging, including color fundus photography, wide-field fluorescein angiography, and spectral domain optical coherence tomography, was used to identify the features of macular retinal angiomatous proliferation and chorioretinal anastomosis., Results: Retinal angiomatous proliferation and chorioretinal anastomosis were present in 5 of 21 patients with Coats disease (24%). The lesions appeared as well demarcated, nodular retinal pigment epithelial detachments surrounded by exudate, with retinal vessels continuous with the underlying choroidal neovascularization., Conclusion: Retinal angiomatous proliferation and chorioretinal anastomoses are features observed in a number of children (24% in the present series) with Coats disease and macular involvement. This lesion represents a distinct macular variant of Coats disease that underlies at least a proportion (all in the present series) of the previously described "macular fibrosis" and "subretinal mounds."

Purpose: To validate known and determine new predictors of non-response to ranibizumab in patients with neovascular age-related macular degeneration (AMD) and to incorporate these factors into a prediction rule., Methods: This multicenter, observational cohort study included 391 patients treated with ranibizumab for neovascular AMD. We performed genetic analysis for single nucleotide polymorphisms in AMD-associated genes and collected questionnaires regarding environmental factors and disease history. The primary outcome was non-response to treatment, defined as a loss of visual acuity ≥30% of letters., Results: Of the 391 patients, 47 were classified as non-responsive. Independent predictors for non-response were age, baseline visual acuity, diabetes mellitus and accumulation of risk alleles in the CFH, ARMS2 and VEGF-A genes. The area under the receiver operating characteristic curve was 0.77 (95% confidence interval 0.70-0.84). We derived a clinical prediction rule, with possible total risk scores ranging from 0-19 points. The absolute risk of non-response varied from 3-52% between risk score groups., Conclusion: This is an important step towards a clinical prediction rule that can aid clinicians in identifying AMD patients with increased likelihood of non-response, and consequently contribute to making shared treatment decisions.

Purpose: Müller cells, the major glial cell in the retina, play a significant role in retinal neovascularization in response to tissue hypoxia. We previously designed and tested a vector using a hypoxia-responsive domain and a glial fibrillary acidic protein (GFAP) promoter to drive green fluorescent protein (GFP) expression in Müller cells in the murine model of oxygen-induced retinopathy (OIR). This study compares the efficacy of regulated and unregulated Müller cell delivery of endostatin in preventing neovascularization in the OIR model., Methods: Endostatin cDNA was cloned into plasmids with hypoxia-regulated GFAP or unregulated GFAP promoters, and packaged into self-complementary adeno-associated virus serotype 2 vectors (scAAV2). Before placement in hyperoxia on postnatal day (P)7, mice were given intravitreal injections of regulated or unregulated scAAV2, capsid, or PBS. Five days after return to room air, on P17, neovascular and avascular areas, as well as expression of the transgene and vascular endothelial growth factor (VEGF), were compared in OIR animals treated with a vector, capsid, or PBS., Results: The hypoxia-regulated, glial-specific, vector-expressing endostatin reduced neovascularization by 93% and reduced the central vaso-obliteration area by 90%, matching the results with the unregulated GFAP-Endo vector. Retinas treated with the regulated endostatin vector expressed substantial amounts of endostatin protein, and significantly reduced VEGF protein. Endostatin production from the regulated vector was undetectable in retinas with undamaged vasculature., Conclusions: These findings suggest that the hypoxia-regulated, glial cell-specific vector expressing endostatin may be useful for treatment of neovascularization in proliferative diabetic retinopathy., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)

Pathological angiogenesis of the retina is a key component of irreversible causes of blindness, as observed in proliferative diabetic retinopathy, age-related macular degeneration, and retinopathy of prematurity. Seminal studies in the early 1980 s about the angiogenic activity exerted by mammalian retinal tissue extracts on the chick embryo chorioallantoic membrane and the later discovery of vascular endothelial growth factor (VEGF) accumulation in eyes of patients with diabetic retinopathy paved the way for the development of anti-angiogenic VEGF blockers for the treatment of retinal neovascularization. Since then, numerous preclinical and clinical studies about diabetic retinopathy and other retinal disorders have opened new lines of angiogenesis inquiry, indicating that limitations to anti-VEGF therapies may exist. Moreover, the production of growth factors other than VEGF may affect the response to anti-VEGF approaches. Thus, experimental models of retinal angiogenesis remain crucial for investigating novel anti-angiogenic therapies and bringing them to patients. To this aim, in vitro and ex vivo angiogenesis assays may be suitable for a rapid screening of potential anti-angiogenic molecules before in vivo validation of the putative lead compounds. This review focuses on the different in vitro and ex vivo angiogenesis assays that have been developed over the years based on the isolation of endothelial cells from the retina of various animal species and ex vivo cultures of neonatal and adult retina explants. Also, recent observations have shown that eye neovascularization in zebrafish (Danio rerio) embryos, an in vivo animal platform experimentally analogous to in vitro/ex vivo models, may represent a novel target for the identification of angiogenesis inhibitors. When compared to in vivo assays, in vitro and ex vivo models of retina neovascularization, including zebrafish embryo, may represent cost-effective and rapid tools for the screening of novel anti-angiogenic therapeutics.

Leber congenital amaurosis is a severe retinal dystrophy that causes blindness or severe visual impairment, usually before the age of 1 year. We present the case of a 13-year-old girl with Leber congenital amaurosis who developed an exudative vasculopathy. She was successfully treated with cryotherapy and argon green laser. To our knowledge, only 4 cases of this condition in patients with Leber congenital amaurosis have been reported previously. This phenotype may be related to c.2991+1655A>G (p.Cys998X) mutations in the CEP290 gene., (Copyright © 2014 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.)

Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a key coordinator of gene programs in metabolism and energy homeostasis in mammals. The aim of this study was to determine whether PGC-1α is involved in the transcriptional regulation of retinal neovascularization in oxygen-induced retinopathy (OIR). The expression of PGC-1α in the retina of mice with OIR was detected by real-time polymerase chain reaction (PCR) and western blot analysis. Mice with OIR were administered small interfering RNA (siRNA) targeting PGC-1α by intravitreal injection, and the effects of PGC-1α siRNA were confirmed by fluorescein angiography and quantification of pre-retinal neovascular nuclei in the retinal sections. PGC-1α was upregulated at both the mRNA and protein level under hypoxic conditions. Retinal neovascularization was inhibited by PGC-1α siRNA. Furthermore, PGC-1α mRNA and protein levels were also reduced by PGC-1α siRNA, which were detected by real-time PCR and western blot analysis. The downregulation of PGC-1α expression resulted in the reduction of vascular endothelial growth factor (VEGF) expression in the mice. In conclusion, siRNA targeting PGC-1α inhibits retinal neovascularization by downregulating the expression of PGC-1α and VEGF in the murine retina. Therefore, PGC-1α represents a potential therapeutic target for ischemia-induced retinal diseases and other ocular neovascular diseases.

15-lipoxygenase-1 (15-LOX-1) plays an important role in angiogenesis, but how it works still remains a controversial subject. The aims of our study are focused on determining whether or not 15-LOX-1 inhibiting oxygen-induced ischemic retinal neovascularization (RNV) and the underlying regulatory mechanism involving of 15-LOX-1, peroxisome proliferator-activated receptor γ (PPAR-γ) and vascular endothelial growth factor receptor 2 (VEGFR-2) in oxygen-induced retinopathy (OIR). Recombinant adenoviral vectors that expressing the 15-LOX-1 gene (Ad-15-LOX-1-GFP) or the green fluorescence protein gene (Ad-GFP) were intravitreous injected into the OIR mice at postnatal day 12 (P12), the mice were sacrificed 5 days later (P17). Retinal 15-LOX-1 expression was significantly increased at both mRNA and protein levels after 15-LOX-1 gene transfer. Immunofluorescence staining of retinal sections revealed 15-LOX-1 expression was primarily in the outer plexiform layer (OPL), inner nuclear layer (INL) and ganglion cell layer (GCL) retina. Meanwhile, RNV was significantly inhibited indicated by fluorescein retinal angiography and quantification of the pre-retinal neovascular cells. The expression levels of PPAR-γ were significantly up-regulated while VEGFR-2 were significantly down-regulated both in mRNA and protein levels. Our results suggested 15-LOX-1 gene transfer inhibited RNV in OIR mouse model via up-regulation of PPAR-γ and further down-regulation of VEGFR-2 expression. This could be a potentially important regulatory mechanism involving 15-LOX-1, PPAR-γ and VEGFR-2 during RNV in OIR. In conclusion, 15-LOX-1 may be a new therapeutic target for treating neovascularization diseases.

Background: Previous studies have proven that long-lasting success in the therapy of neovascular age-related macular degeneration (AMD) and other neovascular retinal diseases depends on monthly follow-up examinations to assess visual acuity and retinal morphology., Materials and Methods: The interactive database Bonn ophthalmology online network (BOON) offers a platform for patient monitoring, increasing control reliability and providing a tool for permanent communication between treating centers and referring ophthalmologists. The BOON data-based project started in 2009 at the department of ophthalmology at Bonn University and ten referring ophthalmology practices. It was programmed to communicate diagnostic findings, images and patient appointments online. In order to react promptly the system gave immediate notice if patients had missed a follow-up appointment or the condition had worsened. Patients were recruited in 2009 and 2010 and were followed for 1 year. Each patient had an electronic master file with several registers in which, besides personal data, precise diagnostic findings, imaging and reports were quickly and easily entered by means of detailed check box and drop-down menus. Each follow-up was registered and an alert email was sent to the referring physician in cases of missed appointments or disease progression., Results and Conclusions: The BOON database supports the requirements for a fast and detailed communication between treating and referring physicians in the treatment of patients with AMD as well as other retinal diseases. It was programmed to support data exchange and monthly control visits and thus a better patient management. Results will show whether this helps to enhance long-term treatment success in neovascular diseases.

Herein, we discuss recent applications of nanotechnology to ophthalmology, including nanoparticles for drug, gene, and trophic factor delivery; regenerative medicine (in the areas of optogenetics and optic nerve regeneration); and diagnostics (eg, minimally invasive biometric monitoring). Specific applications for the management of choroidal neovascularization, retinal neovascularization, oxidative damage, optic nerve damage, and retinal degenerative disease are considered. Nanotechnology will play an important role in early- and late-stage interventions in the management of blinding diseases., (Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

The authors report a rare case of a 48-year-old male with chronic myeloid leukemia (CML) who initially presented with a bilateral proliferative retinopathy. The patient complained of recent visual loss and floaters in both eyes (BE). Ophthalmologic evaluation revealed a best corrected visual acuity (BCVA) of 20/50 in the right eye and 20/200 in the left eye (LE). Fundoscopy showed the presence of bilateral peripheral capillary dropout with multiple retinal sea fan neovascularisations, which were confirmed on fluorescein angiography. Full blood count revealed hyperleukocytosis, thrombocytosis, anemia, and hyperuricemia. Bone marrow aspiration and biopsy showed the reciprocal chromosomal translocation t (9;22), diagnostic of CML. The patient was started on hydroxyurea, allopurinol and imatinib mesylate. He received bilateral panretinal laser photocoagulation and a vitrectomy was performed in the LE. The patient has been in complete hematologic, cytogenetic, and major molecular remission while on imatinib and his BCVA is 20/25 in BE.