The choroid, a vascularized tissue situated between the retina and the sclera, plays a crucial role in maintaining ocular homeostasis. Despite its significance, research on choroidal abnormalities and the establishment of effective in vitro models have been limited. In this study, we developed an in vitro choroid model through the co-culture of human induced pluripotent stem cells (hiPSC)-derived endothelial cells (ECs) and mouse choroidal fibroblasts (msCFs) with hiPSC-derived retinal pigment epithelial (RPE) cells via a permeable membrane. This model, inclusive of ECs, CFs, and RPE cells, exhibited similarities with in vivo choroidal vessels, as confirmed through immunohistochemistry of extracellular matrix markers and vascular-related markers, as well as choroid angiogenesis sprouting assay analysis. The effectiveness of our in vitro model was demonstrated in assessing vascular changes induced by drugs targeting vasoregulation. Our model offers a valuable tool for gaining insights into the pathological mechanisms underlying choroid development and the progression of choroidal vascular diseases.

Identifying macular neovascularization (MNV) in eyes with central serous chorioretinopathy (CSC) has important implications for its management. Optical coherence tomography angiography (OCTA) is increasingly used for this purpose. Here, we systematically reviewed the literature and conducted meta-analysis to determine the diagnostic accuracy of OCTA for detecting MNV in eyes with CSC. We systematically searched the literature in 12 databases for relevant studies from database inception until 18 November 2023. Eligible studies had eyes with CSC with MNV and CSC without MNV. Index test was OCTA. Reference test was retinal dye angiography. Study selection and data extraction were performed in duplicate, and study was evaluated using the Quality Assessment of Diagnostic Accuracy Studies 2. Our main outcome of interest was the sensitivity and specificity of OCTA for detecting MNV in CSC. Pooled diagnostic test accuracy estimates were computed using MetaDTA. Of 177 records screened, seven fulfilled the eligibility criteria for our study. These studies summarized data from a total of 1061 eyes. Summary estimate sensitivity and specificity to diagnose MNV in eyes with CSC using OCTA was 92.9% (95% CI: 81.7%-97.5%) and 99.4% (95% CI: 84.1%-100.0%), respectively. The main source of bias across studies was the reference standard, as four studies used multimodal imaging including OCTA for the reference standard. OCTA alone is excellent for detecting MNV in CSC compared to retinal dye angiography or multimodal imaging. Using OCTA first before considering retinal dye angiography could potentially save an important number of retinal dye angiographies.

UNASSIGNED: The cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) stimulator of interferon gene (STING) pathway is a crucial cascade in the inflammatory response initiated by the recognition of cytosolic double-stranded DNA (dsDNA). The aim of this study was to evaluate the effect of STING inhibitor in murine choroidal neovascularization (CNV).
UNASSIGNED: To investigate whether the cGAS-STING pathway is activated during CNV, CNV was induced using laser photocoagulation in male C57BL/6J mice. The expression of change of cGAS and STING during CNV development was confirmed by Western-blotting. H-151, a potent STING palmitoylation antagonist, was used as a STING inhibitor. H-151 was administered intravitreally immediately after laser induction. To confirm the role of the cGAS-STING pathway in CNV formation, we evaluated CNV size and performed fundus fluorescein angiography.
UNASSIGNED: The expression levels of cGAS and STING were significantly upregulated in the RPE-choroid complex after CNV induction, and dsDNA merged with cGAS was observed in CNV lesions. Intravitreal administration of H-151 suppressed CNV development and fluorescent leakage from neovessels. In CNV lesions, the high expression of STING and cGAS was observed in infiltrating F4/80+ macrophages. H-151 administration attenuated downstream signals of the cGAS-STING pathway, including the phosphorylation of nuclear factor-κB, and downregulated the expression of interleukin 1β.
UNASSIGNED: These findings support that the inhibition of cGAS-STING pathway treats abnormal ocular angiogenesis.

UNASSIGNED: This study revealed a core regulator and common upstream mechanisms for the multifaceted pathological processes of age-related macular degeneration (AMD) and provided proof-of-concept for this new therapeutic target.
UNASSIGNED: Comprehensive gene expression analysis was performed using RNA sequencing of eye cup from old mice as well as laser-induced choroidal neovascularization (CNV) mouse model. Through integrative analysis and protein-protein interaction (PPI) analysis, common pathways and key transcription factor was identified simultaneously engaged in age-related retinal degeneration and CNV, the two typical pathological process of AMD. Subsequently, the expression changes of Spi1, the key regulator, as well as the alternation of the downstream mechanisms were validated in both models through qRT-PCR, Elisa, flow cytometry and immunofluorescence. Further, we assessed the impact of Spi1 knockdown in vitro and in vivo using gene intervention vectors carried by adeno-associated virus or lentivirus to test its potential as a therapeutic target.
UNASSIGNED: Compared to corresponding controls, we found 1,939 and 1,319 genes differentially expressed in eye cups of old and CNV mice respectively. The integrative analysis identified a total of 275 overlapping DEGs, of which 150 genes were co-upregulated. PPI analysis verified a central transcription factor, SPI1. The significant upregulation of Spi1 expression was then validated in both models, accompanied by macrophage polarization towards the M1 phenotype. Finally, SPI1 suppression significantly inhibited M1 polarization of BMDMs and attenuated neovascularization in CNV mice.
UNASSIGNED: This study demonstrates that SPI1 exerts a pivotal role in AMD by regulation of macrophage polarization and innate immune response, offering promise as an innovative target for treating AMD.

UNASSIGNED: Recruitment and activation of inflammatory cells, such as retinal microglia/macrophages, in the subretinal space contribute significantly to the pathogenesis of age-related macular degeneration (AMD). This study aims to explore the functional role of vascular endothelial growth factor (VEGF-A), placental growth factor (PlGF) and VEGF-A/PlGF heterodimer in immune homeostasis and activation during pathological laser-induced choroidal neovascularization (CNV).
UNASSIGNED: To investigate these roles, we utilized the PlGF-DE knockin (KI) mouse model, which is the full functional knockout (KO) of PlGF. In this model, mice express a variant of PlGF, named PlGF-DE, that is unable to bind and activate VEGFR-1 but can still form heterodimer with VEGF-A.
UNASSIGNED: Our findings demonstrate that, although there is no difference in healthy conditions, PlGF-DE-KI mice exhibit decreased microglia reactivity and reduced recruitment of both microglia and monocyte-macrophages, compared to wild-type mice during laser-induced CNV. This impairment is associated with a reduction in VEGF receptor 1 (VEGFR-1) phosphorylation in the retinae of PlGF-DE-KI mice compared to C57Bl6/J mice. Corroborating these data, intravitreal delivery of PlGF or VEGF-A/PlGF heterodimer in PlGF-DE-KI mice rescued the immune cell response at the early phase of CNV compared to VEGF-A delivery.
UNASSIGNED: In summary, our study suggests that targeting PlGF and the VEGF-A/PlGF heterodimer, thereby preventing VEGFR-1 activation, could represent a potential therapeutic approach for the management of inflammatory processes in diseases such as AMD.

The prevalence of vision impairment is increasing at an alarming rate. The goal of the study was to create an automated method that uses optical coherence tomography (OCT) to classify retinal disorders into four categories: choroidal neovascularization, diabetic macular edema, drusen, and normal cases. This study proposed a new framework that combines machine learning and deep learning-based techniques. The utilized classifiers were support vector machine (SVM), K-nearest neighbor (K-NN), decision tree (DT), and ensemble model (EM). A feature extractor, the InceptionV3 convolutional neural network, was also employed. The performance of the models was evaluated against nine criteria using a dataset of 18000 OCT images. For the SVM, K-NN, DT, and EM classifiers, the analysis exhibited state-of-the-art performance, with classification accuracies of 99.43%, 99.54%, 97.98%, and 99.31%, respectively. A promising methodology has been introduced for the automatic identification and classification of retinal disorders, leading to reduced human error and saved time.

Age-related macular degeneration (AMD) is a common cause of vision loss. The aggressive form of AMD is associated with ocular neovascularization and subretinal fibrosis, representing a responsive outcome against neovascularization mediated by epithelial-mesenchymal transition of retinal pigment epithelium (RPE) cells. A failure of the current treatment (anti-vascular endothelial growth factor therapy) has also been attributed to the progression of subretinal fibrosis. Hypoxia-inducible factors (HIFs) increase gene expressions to promote fibrosis and neovascularization. HIFs act as a central pathway in the pathogenesis of AMD. HIF inhibitors may suppress ocular neovascularization. Nonetheless, further investigation is required to unravel the aspects of subretinal fibrosis. In this study, we used RPE-specific HIFs or von Hippel-Lindau (VHL, a regulator of HIFs) conditional knockout (cKO) mice, along with pharmacological HIF inhibitors, to demonstrate the suppression of subretinal fibrosis. Fibrosis was suppressed by treatments of HIF inhibitors, and similar suppressive effects were detected in RPE-specific Hif1a/Hif2a- and Hif1a-cKO mice. Promotive effects were observed in RPE-specific Vhl-cKO mice, where fibrosis-mediated pathologic processes were evident. Marine products\' extracts and their component taurine suppressed fibrosis as HIF inhibitors. Our study shows critical roles of HIFs in the progression of fibrosis, linking them to the potential development of therapeutics for AMD.

Rationale: Current treatments for ocular angiogenesis primarily focus on blocking the activity of vascular endothelial growth factor (VEGF), but unfavorable side effects and unsatisfactory efficacy remain issues. The identification of novel targets for anti-angiogenic treatment is still needed. Methods: We investigated the role of tsRNA-1599 in ocular angiogenesis using endothelial cells, a streptozotocin (STZ)-induced diabetic model, a laser-induced choroidal neovascularization model, and an oxygen-induced retinopathy model. CCK-8 assays, EdU assays, transwell assays, and matrigel assays were performed to assess the role of tsRNA-1599 in endothelial cells. Retinal digestion assays, Isolectin B4 (IB4) staining, and choroidal sprouting assays were conducted to evaluate the role of tsRNA-1599 in ocular angiogenesis. Transcriptomic analysis, metabolic analysis, RNA pull-down assays, and mass spectrometry were utilized to elucidate the mechanism underlying angiogenic effects mediated by tsRNA-1599. Results: tsRNA-1599 expression was up-regulated in experimental ocular angiogenesis models and endothelial cells in response to angiogenic stress. Silencing of tsRNA-1599 suppressed angiogenic effects in endothelial cells in vitro and inhibited pathological ocular angiogenesis in vivo. Mechanistically, tsRNA-1599 exhibited little effect on VEGF signaling but could cause reduced glycolysis and NAD+/NADH production in endothelial cells by regulating the expression of HK2 gene through interacting with YBX1, thus affecting endothelial effects. Conclusions: Targeting glycolytic reprogramming of endothelial cells by a tRNA-derived small RNA represents an exploitable therapeutic approach for ocular neovascular diseases.

Choroidal neovascular membrane (CNVM) in Vogt-Koyanagi-Harada disease (VKH) is a known entity, observed primarily during the chronic convalescent and chronic-recurrent phases of the disease. However, the peripapillary location of CNVM is a rare finding.We describe a case of chronic VKH with bilateral peripapillary CNVM detected using multimodal imaging and the associated differential diagnoses and treatment approach.A combination of anti-vascular endothelial growth factor injections, systemic steroids and immunosuppressants is often required to manage the aggressive course of this choroidal neovascularisation.

To compare the efficacy and safety of the proposed aflibercept biosimilar SCD411 and reference aflibercept in patients with neovascular age-related macular degeneration, this randomized, double-masked, parallel-group, multicenter study was conducted in 14 countries from 13 August 2020 to 8 September 2022. Patients with neovascular age-related macular degeneration. With subfoveal, juxtafoveal, or extrafoveal choroidal neovascularization were aged 50 years or older. Intravitreal injection of SCD411 or aflibercept (2.0 mg) were administered every 4 weeks for the first three injections and every 8 weeks until week 48. The primary efficacy endpoint was the change in best-corrected visual acuity from baseline to week 8 with an adjusted equivalence margin of ± 3.0 letters. Patients were randomly assigned to receive either SCD411 (n = 288) or reference aflibercept (n = 288). A total of 566 participants (98.3%) completed week 8 of the study. The least-squares mean difference of change in best-corrected visual acuity from baseline to week 8 (SCD411-aflibercept) was - 0.4 letters (90% confidence interval =  - 1.6 to 0.9). The incidence of ocular (69 of 287 [24.0%] vs. 71 of 286 [24.8%]) and serious ocular (5 of 287 [1.7%] vs. 3 of 286 [1.0%]) treatment-emergent adverse effects were similar between the SCD411 and aflibercept groups. Immunogenicity analysis revealed a low incidence of neutralizing antibody formation in both groups. In conclusion, SCD411 has equivalent efficacy compared with reference aflibercept in patients with neovascular age-related macular degeneration and has a comparable safety profile. The results support the potential use of SCD411 for the treatment of neovascular age-related macular degeneration.