When accumulation of a malfolded protein in the endoplastic reticulum (ER) is induced by various adverse conditions, such as hypoxia, glucose starvation, and perturbation of calcium homeostasis, cells respond to the stress by increasing transcription of genes encoding ER molecular chaperones, a process known as unfolded protein response. The signaling is initiated by IRE1s, ER stress sensors. Alternatively, excessive stress to the ER results in apoptosis. Caspase-12 is known to be essential for this ER stress-induced apoptosis. In this study, we analyzed the detailed regulatory mechanisms of IRE1s during ER stress. We identified c-Jun N-terminal inhibitory kinase (JIK) as a binding partner of IRE1α, and JIK was seen to modulate IRE1α-TRAF2 (tumor necrosis factor receptor-associated factor 2) complex formation and the resultant alteration to c-Jun N-terminal kinase signaling from IRE1s in response to ER stress. We also demonstrated that TRAF2 interacts with procaspase-12 and promotes the clustering of procaspase-12 and its activation by cleavage in response to ER stress. These results indicate that TRAF2 plays crucial roles not only in the signaling of the c-Jun N-terminal kinase pathway but also in activation of caspase-12 to transduce signals from IRE1s. Thus, we provide a missing link in the ER stress-induced apoptosis-signaling pathway, one which connects the stress sensor molecule IRE1 and the activation of caspase-12.

Aims: The aim of the study was to assess the short-term efficacy of intravitreal injections of bevacizumab for polypoidal choroidal vasculopathy (PCV). Methods: Intravitreal bevacizumab (1 mg) was injected into 11 eyes of 11 patients with PCV in this retrospective, interventional case series. The main outcome measure was the change in the polypoidal vessels on indocyanine green angiography (IA) 3 months after injection. The foveal height determined by optical coherence tomography and the best-corrected visual acuity (BCVA) also were evaluated before and after treatment. Results: At baseline, subretinal fluid was observed in five eyes and a pigment epithelial detachment in eight eyes. The foveal height 1 month after injection decreased significantly (p = 0.023), but at 3 months, no significant decrease was observed, although an additional injection was administrated in five of 11 eyes. The IA at 3 months showed resolution of polyps in one eye but residual or enlarged lesions in the other ten eyes. The BCVA did not improve significantly, although the subjects had relatively good BCVA at baseline (mean 0.45). Conclusion: Intravitreal injection of bevacizumab may reduce the fluid from PCV but seems to be ineffective for diminishing its choroidal vascular changes.

To develop consensus terminology in the setting of polypoidal choroidal vasculopathy (PCV) and to develop and validate a set of diagnostic criteria not requiring indocyanine green angiography (ICGA) for differentiating PCV from typical neovascular age-related macular degeneration (nAMD) based on a combination of OCT and color fundus photography findings. Evaluation of diagnostic test results. Panel of retina specialists. As part of the Asia-Pacific Ocular Imaging Society, an international group of experts surveyed and discussed the published literature regarding the current nomenclature and lesion components for PCV, and proposed an updated consensus nomenclature that reflects our latest understanding based on imaging and histologic reports. The workgroup evaluated a set of diagnostic features based on OCT images and color fundus photographs for PCV that may distinguish it from typical nAMD and assessed the performance of individual and combinations of these non-ICGA features, aiming to propose a new set of diagnostic criteria that does not require the use of ICGA. The final recommendation was validated in 80 eyes from 2 additional cohorts. Consensus nomenclature system for PCV lesion components and non-ICGA-based criteria to differentiate PCV from typical nAMD. The workgroup recommended the terms polypoidal lesion and branching neovascular network for the 2 key lesion components in PCV. For the diagnosis of PCV, the combination of 3 OCT-based major criteria (sub-retinal pigment epithelium [RPE] ring-like lesion, en face OCT complex RPE elevation, and sharp-peaked PED) achieved an area under the receiver operating characteristic curve of 0.90. Validation of this new scheme in a separate subset 80 eyes achieved an accuracy of 82%. We propose updated terminology for PCV lesion components that better reflects the nature of these lesions and is based on international consensus. A set of practical diagnostic criteria applied easily to spectral-domain OCT results can be used for diagnosing PCV with high accuracy in clinical settings in which ICGA is not performed routinely.

During development, the retinal vasculature grows toward hypoxic areas in an organized fashion. By contrast, in ischemic retinopathies, new blood vessels grow out of the retinal surfaces without ameliorating retinal hypoxia. Restoration of proper angiogenic directionality would be of great benefit to reoxygenize the ischemic retina and resolve disease pathogenesis. Here, we show that binding of the semaphorin 3E (Sema3E) ligand to the transmembrane PlexinD1 receptor initiates a signaling pathway that normalizes angiogenic directionality in both developing retinas and ischemic retinopathy. In developing mouse retinas, inhibition of VEGF signaling resulted in downregulation of endothelial PlexinD1 expression, suggesting that astrocyte-derived VEGF normally promotes PlexinD1 expression in growing blood vessels. Neuron-derived Sema3E signaled to PlexinD1 and activated the small GTPase RhoJ in ECs, thereby counteracting VEGF-induced filopodia projections and defining the retinal vascular pathfinding. In a mouse model of ischemic retinopathy, enhanced expression of PlexinD1 and RhoJ in extraretinal vessels prevented VEGF-induced disoriented projections of the endothelial filopodia. Remarkably, intravitreal administration of Sema3E protein selectively suppressed extraretinal vascular outgrowth without affecting the desired regeneration of the retinal vasculature. Our study suggests a new paradigm for vascular regeneration therapy that guides angiogenesis precisely toward the ischemic retina.