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Autoimmune uveitis is a sight-threatening disease induced by pathogenic T cells that recognize retinal antigens; it is observed in disorders including Vogt-Koyanagi-Harada disease (VKH). The roles of specific T cell subsets and their therapeutic potential against autoimmune uveitis are not fully understood. Here we conducted multi-parametric single-cell protein quantification which shows that the frequency of CD161highTRAV1-2+ mucosal-associated invariant T (MAIT) cells that recognize vitamin B2 metabolite-based antigens is decreased in relapsing VKH patients compared to individuals without active ocular inflammation. An experimental autoimmune uveitis (EAU) mouse model revealed that genetic depletion of MAIT cells reduced the expression of interleukin (Il) 22 and exacerbated retinal pathology. Reduced IL-22 levels were commonly observed in patients with relapsing VKH compared to individuals without active ocular inflammation. Both mouse and human MAIT cells produced IL-22 upon stimulation with their antigenic metabolite in vitro. An intravitreal administration of the antigenic metabolite into EAU mice induced retinal MAIT cell expansion and enhanced the expressions of Il22, as well as its downstream genes related to anti-inflammatory and neuroprotective effects, leading to an improvement in both retinal pathology and visual function. Taken together, we demonstrate that a metabolite-driven approach targeting MAIT cells has therapeutic potential against autoimmune uveitis.

At present, ≥ 20% of patients experience clinically relevant postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP).We developed a new bioabsorbable pancreatic clip (BioPaC) made of polycaprolactone that does not crush the pancreatic parenchyma during occlusion of the pancreatic stump. We confirmed the efficacy of this BioPac in a porcine DP model and compared it to a linear stapling device (Reinforce®).Pigs were killed at 1 month after DP. In the BioPaC group, all swine (n = 3) survived well without POPF. In the Reinforce® group (n = 2), one pig died early at postoperative day 7 with Grade C POPF (amylase 43 700 U/l), and the other survived until 1 month at scarification with biochemical leakage of POPF (amylase 3 725 U/l). Pathologically, the main pancreatic duct and pancreatic parenchyma were well closed by BioPaC.The newly developed BioPaC is effective in a porcine DP model.

Intraretinal hyperreflective foci (HRF) are significant biomarkers for diabetic macular edema. However, HRF at the vitreoretinal interface (VRI) have not been examined in diabetic retinopathy (DR). A prospective observational clinical study with 162 consecutive eyes using OCT imaging showed significantly increased HRF at the VRI during DR progression (Pvegfa+/+) or Akimba (Akita × Kimba) mice (both PIns2+/-) mice, indicating macrophage activation was modulated by elevated VEGF rather than the diabetic milieu. Macrophage depletion significantly reduced HRF at the VRI (PCcr2rfp/+Cx3cr1gfp/+ vegfa+/- mice identified a significant contribution of M2-like tissue-resident macrophages (TRMs) at the VRI. Ki-67- and CD11b-positive cells were observed in preretinal tissues of DR patients while exposure of vitreal macrophages to vitreous derived from PDR patients induced a significant proliferation response in vitro (P

Detecting subtle vitreoretinal interface (VRI) findings, such as a posterior hyaloid membrane, is difficult with conventional retinal imaging. We compared ultra-high-resolution spectral domain optical coherence tomography (UHR-SD-OCT) with standard-resolution OCT (SD-OCT) for the imaging of VRI abnormalities in diabetic retinopathy (DR).This prospective cross-sectional study included 113 consecutive patients (91 patients with diabetes and 22 healthy controls). The VRI was evaluated, and the results were compared between the conventional SD-OCT and UHR-SD-OCT images. VRI findings were also investigated before and after internal limiting membrane peeling during vitrectomy for proliferative DR.A total of 159 eyes (87.4%) of 91 patients with diabetes were analyzed. UHR-SD-OCT could detect a hyperreflective layer at the VRI, in which en face OCT showed a membrane-like structure, termed the hyperreflective membrane (HRMe). The preoperative HRMe could not be detected in all patients with proliferative DR who underwent internal limiting membrane peeling during vitrectomy. Although the HRMe did not correlate with the DR stage, eyes with diabetic macular edema (DME) (64.5%) showed a significant HRMe with UHR-SD-OCT more frequently than those without DME (35.8%) (P = 0.005).UHR-SD-OCT can detect the HRMe at the VRI in DR eyes, particularly in eyes with DME. The HRMe may present a thickened posterior hyaloid membrane that contributes to DME development.UHR-SD-OCT detects slight changes in the VRI in DR eyes. In the future, it may help to elucidate the mechanism of DME formation.

Background/objectives The prevalence of myopia is higher in preterm infants who underwent laser photocoagulation (LPC) for retinopathy of prematurity (ROP). The aim of this study was to investigate factors associated with myopia in preterm infants who undergo LPC for ROP. Subjects/methods We retrospectively analysed the medical records of preterm infants born at Kyushu University Hospital (October 2008-March 2018) at ≤32 weeks of gestational age or with birth weight ≤1500 g. We evaluated the associations between nine clinical factors and the spherical equivalent at 1-year corrected age by performing multivariable linear regression in LPC-treated ROP patients. Results Among the 485 infants enroled, 76 developed ROP requiring treatment. Of these, 71 underwent LPC, which was provided to 63 infants as the primary treatment (LPC alone or the combination therapy of LPC and intravitreal injection of bevacizumab [IVB]) and to eight infants as additional LPC after IVB monotherapy. The results of a refractive examination at 1-year corrected age were available for 110 eyes of 56 infants (78.9%). The mean ± standard deviation of the SE value was -0.5 ± 3.0 dioptres (D). Multivariable linear regression analysis revealed a significant association between laser spot count and SE value (s = -0.081 ± 0.040 D per 100 spots [mean ± standard error], p = 0.045). Conclusions Our results suggest that an increased laser spot count observed during ROP treatment associates with myopia.

To investigate the relevance of microaneurysm morphology in optical coherence tomography angiography (OCTA) image averaging and fluorescein leakage in diabetic retinopathy (DR).In 38 consecutive patients with DR, ten consecutive 3- × 3-mm fovea-centered OCTA (HS100, Canon Inc., Tokyo, Japan) and fluorescein angiography (FA) were performed, and averaged OCTA images were created based on the 10 images. After detecting all microaneurysms in FA images, the morphology was classified into four types (focal bulge, saccular/pedunculated, fusiform, and mixed) using averaged OCTA images. The correlation between microaneurysm leakage in FA, retinopathy stage, and microaneurysm morphology was estimated.Thirty-eight eyes (50.0%) of the 33 patients were available for analysis, and 370 (63.5%) of the 583 FA-detected microaneurysms were morphologically classifiable (focal bulge, 46; saccular/pedunculated, 143; fusiform, 29; and mixed, 152) in OCTA. There was a significant correlation between stage and percentage of microaneurysm morphology and between morphology and the presence of leakage (P 0.0001 and P 0.01, respectively). The proportion of focal bulges decreased with stage progression, while the other three types increased with stage progression. The percentage of FA leakage for focal bulge, saccular/pedunculated, fusiform, and mixed was 41.3%, 66.4%, 82.8%, and 66.4%, respectively, and the fusiform type showed significant FA leakage.Microaneurysm morphology is correlated with the DR stage and FA leakage. Microaneurysm morphology recognition using OCTA image averaging may be useful for the clinical evaluation of DR.

Purpose No lymphatic vessels have been identified in the retina. This study investigated whether pathological VEGF-A–overexpressing diabetic retina causes lymphangiogenesis. Methods Three genetic mouse models of diabetic retinopathy (DR) (Akita [Ins2+/−], Kimba [vegfa+/+], and Akimba [Akita × Kimba] mice) were used. Retinas were examined by fundus photography, fluorescence angiography (FA), and immunostaining to detect lymphangiogenesis or angiogenesis. Lyve1-GFP (Lyve1EGFP/Cre) mice were used to examine Lyve1-expressing cells by immunostaining. Lymphatic-related factors were investigated in mouse retina and vitreous fluid from proliferative diabetic retinopathy (PDR) patients by RT-PCR and ELISA, respectively. Aged Kimba and Akimba mice were used to examine the retinal phenotype at the late phase of VEGF overexpression. Results FA and immunostaining showed retinal neovascularization in Kimba and Akimba mice but not wild-type and Akita mice. Immunohistochemistry showed that lymphangiogenesis was not present in the retinas of Akita, Kimba, or Akimba mice despite the significant upregulation of lymphatic-related factors (Lyve1, podoplanin, VEGF-A, VEGF-C, VEGF-D, VEGFR2, and VEGFR3) in the retinas of Kimba and Akimba mice by RT-PCR (P < 0.005). Furthermore, lymphangiogenesis was not present in aged Kimba or Akimba mice. Significantly increased numbers of Lyve1-positive cells present in the retinas of Kimba and Akimba mice, especially in the peripheral areas, were CD11b positive, indicating a macrophage population (P < 0.005). VEGF-C in PDR vitreous with vitreous hemorrhage (VH) was higher than in PDR without VH or a macular hole. Conclusions Retinal VEGF-A overexpression did not cause typical lymphangiogenesis despite upregulated lymphatic-related factors and significant Lyve1-positive macrophage infiltration.

Lifelong visual impairment occurs from retinal diseases due to the inability of photoreceptor cells to regenerate in mammals. We demonstrated that endogenous Müller cells (MCs) in mice differentiate into photoreceptor-like cells by intravitreal injection of four small-molecule compounds: tumor growth factor-β inhibitor, bone morphogenetic protein inhibitor, glycogen synthase kinase 3 inhibitor, and γ-secretase inhibitor. In vitro, the messenger RNA of rhodopsin (Rho) in MCs increased 30-fold, and 25% of cultured MCs expressed Rho protein 7 days after stimulation with these compounds. In vivo, Rho-positive cells were regenerated on day 7 after the intravitreal injection of four compounds, accompanied with recovery of Rho-derived scotopic function. Lineage tracing in mice treated with N-methyl-N-nitrosourea, a disease model of photoreceptor degeneration, showed that the regenerated Rho-positive cells were originated from endogenous MCs. Finally, the regeneration of Rho-positive cells was also induced in the retina of rd10 mice, a model with similar genetic mutation as humans. Notably, the intravitreal injection significantly reduced cone cell death in rd10 mice. This treatment could be a new strategy in retinal regenerative medicine where mammalian endogenous MCs are reprogrammed into photoreceptor cells independent of transplantation or gene transfer.

Autoimmune uveitis is a sight-threatening disease induced by pathogenic T cells that recognize retinal antigens; it is observed in disorders including Vogt-Koyanagi-Harada disease (VKH). The roles of specific T cell subsets and their therapeutic potential against autoimmune uveitis are not fully understood. Here we conducted multi-parametric single-cell protein quantification which shows that the frequency of CD161

Purpose To evaluate structural and angiographic neovascularization in patients with proliferative diabetic retinopathy (PDR) using volumetric three-dimensional optical coherence tomography angiography (OCTA). Methods This prospective, observational cross-sectional study included 29 eyes of 27 patients with PDR. The angiogenic structure, feeding vessel (epicenter), flow volume, and flow volume density (FVD) of the neovasculatures were evaluated using three-dimensional OCTA imaging. The flow area and the flow area density (FAD) were also measured using en face OCTA imaging. Results Sites of neovascularization were imaged successfully in 17 of the 29 eyes (58.6%). Three proposed types of neovascularization were identified on the basis of structural features seen on the three-dimensional OCTA images. Neovascularization of the adhesion type (9 of 17, 52.9%) adhered to the retinal vasculature. Those of the traction type (5 of 17, 29.4%) were partially separated from the retinal vascular plexus. Those of the mushroom type (3 of 17, 17.6%) were connected to the retinal vasculature via several epicenters. There was a significant difference between highly leaky (active) and faintly leaky (inactive) neovascularization for FVD, but not for flow area, flow volume, or FAD (P=0.01, 0.9, 0.6, and 0.1, respectively). Conclusions Volumetric three-dimensional OCTA revealed three types of neovascularization in PDR, and may be useful for assessing neovascular activity and planning vitrectomies.

Atsunobu Takeda,1,2 Eiichi Hasegawa,1 Shoji Notomi,1,2 Keijiro Ishikawa,1 Mitsuru Arima,1,2 Yusuke Murakami,1 Shintaro Nakao,1 Toshio Hisatomi,3 Koh-Hei Sonoda1,4 1Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; 2Department of Ophthalmology, Clinical Research Institute, National Hospital Organization, Kyushu Medical Center, Fukuoka, Japan; 3Department of Ophthalmology, Chikushi Hospital, Fukuoka University, Fukuoka, Japan; 4Department of Ocular Pathology and Imaging Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, JapanCorrespondence: Atsunobu TakedaDepartment of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-Ku, Fukuoka, 812-8582, JapanTel +81-92-642-5648Fax +81-92-642-5663Email takeda.atsunobu.248@m.kyushu-u.ac.jpPurpose: To evaluate the pre- and post-operative outcomes of phacoemulsification in patients with uveitis-associated cataract in remission, such as conventional visual acuity (VA), photopic and mesopic contrast visual acuity (CVA), and flares in the anterior chamber objectively assessed as intraocular inflammation.Patients and Methods: This prospective study included 26 eyes of 19 patients with uveitis and 45 eyes of 26 controls who underwent cataract surgery at the Kyushu University Hospital and Kyushu Medical Center in Fukuoka, Japan, from October 2016 to December 2018. Conventional VA and flare values in the anterior chamber were evaluated preoperatively and 1 and 3 months postoperatively. Photopic and mesopic CVAs were assessed preoperatively and 3 months postoperatively.Results: The best-corrected VA (BCVA) was improved significantly from baseline to 1 and 3 months postoperatively in both groups (P < 0.01 in both groups). The mean preoperative 100% and 10% CVAs under the photopic condition were significantly lower in the uveitis group than in the control group (P < 0.05 for both CVA), whereas the mean preoperative 100% CVA under the mesopic condition was comparable between the two groups. Although the mean preoperative 100% and 10% CVAs improved significantly from baseline under both photopic and mesopic conditions in both groups (P < 0.01 in both groups), the postoperative contrast sensitivities under both photopic and mesopic conditions remained lower in the uveitis group than in the control group (P < 0.01 for both conditions). The postoperative complications included recurrence of active inflammation in five eyes and cystoid macular edema in one eye and were managed by topical steroid therapy alone.Conclusion: Cataract surgery for uveitis-associated cataracts during remission is well tolerated. However, the present results suggest that amelioration of hemeralopia and/or nyctalopia is not as good as expected after cataract surgery in patients with uveitis.Keywords: cataract, phacoemulsification, uveitis, contrast sensitivity, photopic and mesopic conditions

Our study assessed the influence of vascular permeability on vascular flow density (FD)-correlated retinal sensitivity (RS) in DR. In this cross-sectional, prospective, consecutive study, RS in the extrafoveal macula of DR patient was measured by microperimetry. FD was measured in the total, superficial, and deep capillary plexus layers (TCP, SCP, and DCP) by optical coherence tomography angiography. All measurement points were classified into four categories according to intensity of fluorescein leakage and FD, and the RS reduction was compared. A stratified analysis by retinal thickness (RT) was also performed. Fourteen eyes (14 patients) were enrolled. FDs at 207 RS measurement points were analyzable. For TCP, SCP and DCP, the leakage did not decrease RS at points where FD was maintained. The greater the leakage, the smaller the RS reduction at points with low FD in TCP (P = .020). Points with high leakage showed a significant smaller RS reduction than points with low leakage (P = .001 for TCP, P = .040 for SCP, and P = .046 for DCP) only in areas with low RT and low FD. Our results suggested that vascular hyperpermeability may inhibit the RS reduction in the non-edematous ischemic diabetic retina.

Background Pierson syndrome (PS) is a rare autosomal recessive disorder, characterized by congenital nephrotic syndrome and microcoria. Advances in renal replacement therapies have extended the lifespan of patients, whereas the full clinical spectrum of PS in infancy and beyond remains elusive. Case presentation We present the case of a 12-month-old boy with PS, manifesting as the bilateral microcoria and congenital nephrotic syndrome. He was born without asphyxia, and was neurologically intact from birth through the neonatal period. Generalized muscle weakness and hypotonia were recognized from 3 months of age. The infant showed recurrent vomiting at age 5 months of age, and was diagnosed with gastroesophageal reflux and intestinal malrotation. Despite the successful surgical treatment, vomiting persisted and led to severely impaired growth. Tulobuterol treatment was effective in reducing the frequency of vomiting. Targeted sequencing confirmed that he had a compound heterozygous mutation in LAMB2 (NM_002292.3: p.Arg550X and p.Glu1507X). A search of the relevant literature identified 19 patients with severe neuro-muscular phenotypes. Among these, only 8 survived the first 12 months of life, and one had feeding difficulty with similar gastrointestinal problems. Conclusions This report demonstrated that severe neurological deficits and gastrointestinal dysfunction may emerge in PS patients after the first few months of life.

Approximately 40% of patients with diabetic macular edema (DME) are resistant to anti–vascular endothelial growth factor (VEGF) therapy (rDME). Here, we demonstrate that significant correlations between inflammatory cytokines and VEGF, as observed in naive DME, are lost in patients with rDME. VEGF overexpression in the mouse retina caused delayed inflammatory cytokine upregulation, monocyte/macrophage infiltration (CD11b+ Ly6C+ CCR2+ cells), macrophage/microglia activation (CD11b+ CD80+ cells), and blood-retinal barrier disruption due to claudin-5 redistribution, which did not recover with VEGF blockade alone. Phosphorylated protein analysis of VEGF-overexpressed retinas revealed rho-associated coiled-coil–containing protein kinase (ROCK) activation. Administration of ripasudil, a selective ROCK inhibitor, attenuated retinal inflammation and claudin-5 redistribution. Ripasudil also contributed to the stability of claudin-5 expression by both transcriptional enhancement and degradation suppression in inflammatory cytokine–stimulated endothelium. Notably, the anti-VEGF agent and the ROCK inhibitor were synergic in suppressing cytokine upregulation, monocyte/macrophage infiltration, macrophage/microglia activation, and claudin-5 redistribution. Furthermore, in vitro analysis confirmed that claudin-5 redistribution depends on ROCK2 but not on ROCK1. This synergistic effect was also confirmed in human rDME cases. Our results suggest that ROCK-mediated claudin-5 redistribution by inflammation is a key mechanism in the anti-VEGF resistance of DME.

To investigate the roles of P2X7 receptors (P2RX7) in the pathogenesis of experimental autoimmune uveoretinitis (EAU). Experimental. Either wild-type (P2rx7 +/+ ) or P2rx7-deficient (P2rx7 −∕− ) mice were immunized with interphotoreceptor retinoid-binding protein (IRBP) peptide 1-20. Severity of EAU was evaluated clinically and histopathologically. The induction of IRBP-specific proliferation and cytokines in draining lymph nodes was assessed by enzyme-linked immunosorbent assays (ELISA). The frequency of activation markers was examined by flow cytometry. Furthermore, inhibitory roles of systemic administration of Brilliant Blue G (BBG), an antagonist for P2RX7, in EAU were also assessed in the wild-type mice. The severity of EAU in P2rx7 −∕− mice was reduced as compared with that in P2rx7 +/+ mice, both clinically and histopathologically. IRBP-specific proliferation in P2rx7 −∕− on day 16 was slightly decreased compared to that in P2rx7 +/+ mice. The induction of IRBP-specific interferon (IFN)-γ and interleukin (IL)-17 in P2rx7 −∕− mice on day 16 was lower than that in P2rx7 +/+ mice. The up-regulation of surface expression of activation markers such as CD25, CD44, and CD69 in response to TCR stimulation in P2rx7 −∕− mice was decreased as compared with that in P2rx7 +/+ mice. Furthermore, neutralization of P2RX7 in vivo by BBG suppressed EAU clinically and histopathologically. IRBP-specific IFN-γ and IL-17 induction in BBG-treated mice was significantly lower than that in vehicle-treated mice. The results suggest that P2RX7 is a novel preventative therapeutic target for uveitis as it suppresses the effector functions of both Th1 and Th17 cell responses.

Subretinal fibrosis has been recognized as a feature of an advanced stage of exudative age-related macular degeneration (AMD) that leads to irreversible loss of vision. This study was aimed at elucidating roles of interlukin-6 (IL-6) in the development of subretinal fibrosis. Immunohistochemistry (IHC) was performed with anti-human IL-6 antibody in surgically excised choroidal neovascular tissues from patients with exudative AMD. The area of subretinal fibrosis was measured in a mouse subretinal fibrosis model with injection of control small interfering RNA(siRNA) or IL-6 siRNA, or isotype control antibody or anti-IL-6 receptor antibody after peritoneal exudative cells (PECs) injection into the vitreous cavity. PECs derived from IL-6+/+ or IL-6-∕- mice were placed into the subretinal space of IL-6+/+ mice. IL-6 was expressed in the stroma and retinal pigment epithelial (RPE) layer in the choroidal neovascular tissues. IL-6 knockdown or blocking of the IL-6 receptor suppressed the formation of subretinal fibroblastic scars. The area of subretinal fibrosis induced by PECs derived from IL-6-∕- mice was less than that induced by PECs from IL-6+/+ mice. The results suggested that IL-6, expressed by activated macrophages, is a crucial mediator that promotes subretinal fibrosis. Targeting IL-6 and the corresponding signaling pathway would be an attractive therapeutic approach not only in choroidal neovascularization, but also in subretinal fibrosis.

Tenascin-C is expressed in choroidal neovascular (CNV) membranes in eyes with age-related macular degeneration (AMD). However, its role in the pathogenesis of CNV remains to be elucidated. Here we investigated the role of tenascin-C in CNV formation. In immunofluorescence analyses, tenascin-C co-stained with α-SMA, pan-cytokeratin, CD31, CD34, and integrin αV in the CNV membranes of patients with AMD and a mouse model of laser-induced CNV. A marked increase in the expression of tenascin-C mRNA and protein was observed 3 days after laser photocoagulation in the mouse CNV model. Tenascin-C was also shown to promote proliferation and inhibit adhesion of human retinal pigment epithelial (hRPE) cells in vitro. Moreover, tenascin-C promoted proliferation, adhesion, migration, and tube formation in human microvascular endothelial cells (HMVECs); these functions were, however, blocked by cilengitide, an integrin αV inhibitor. Exposure to TGF-β2 increased tenascin-C expression in hRPE cells. Conditioned media harvested from TGF-β2-treated hRPE cell cultures enhanced HMVEC proliferation and tube formation, which were inhibited by pretreatment with tenascin-C siRNA. The CNV volume was significantly reduced in tenascin-C knockout mice and tenascin-C siRNA-injected mice. These findings suggest that tenascin-C is secreted by transdifferentiated RPE cells and promotes the development of CNV via integrin αV in a paracrine manner. Therefore, tenascin-C could be a potential therapeutic target for the inhibition of CNV development associated with AMD.

Necrotizing retinopathies, including acute retinal necrosis (ARN) and progressive outer retinal necrosis (PORN), are a group of uncommon posterior segment complications associated with infections caused by the herpes virus. ARN was first described in 1971 by Urayama et al., Japanese ophthalmologists who termed the condition as Kirisawa uveitis and described it as acute unilateral panuveitis associated with optic neuritis and retinal panarteritis in healthy adults, with subsequent procession to diffuse necrotizing retinitis and/or subsequent rhegmatogenous retinal detachment (RRD) (Urayama et al. 1971). Standard diagnostic criteria for ARN were published by the American Uveitis Committee (Table 27.1) (Holland 1994).

Ischemic proliferative retinopathy (IPR), such as proliferative diabetic retinopathy (PDR), retinal vein occlusion and retinopathy of prematurity is a major cause of vision loss. Our previous studies demonstrated that periostin (PN) and tenascin-C (TNC) are involved in the pathogenesis of IPR. However, the interactive role of PN and TNC in angiogenesis associated with IPR remain unknown. We found significant correlation between concentrations of PN and TNC in PDR vitreous humor. mRNA and protein expression of PN and TNC were found in pre-retinal fibrovascular membranes excised from PDR patients. Interleukin-13 (IL-13) promoted mRNA and protein expression of PN and TNC, and co-immunoprecipitation assay revealed binding between PN and TNC in human microvascular endothelial cells (HRECs). IL-13 promoted angiogenic functions of HRECs. Single inhibition of PN or TNC and their dual inhibition by siRNA suppressed the up-regulated angiogenic functions. Pathological pre-retinal neovessels of oxygen-induced retinopathy (OIR) mice were attenuated in PN knock-out, TNC knock-out and dual knock-out mice compared to wild-type mice. Both in vitro and in vivo, PN inhibition had a stronger inhibitory effect on angiogenesis compared to TNC inhibition, and had a similar effect to dual inhibition of PN and TNC. Furthermore, PN knock-out mice showed scant TNC expression in pre-retinal neovessels of OIR retinas. Our findings suggest that interaction of PN and TNC facilitates pre-retinal angiogenesis, and PN is an effective therapeutic target for IPR such as PDR.

In diabetic retinopathy (DR), OCT angiography (OCTA) could not image all fluorescein angiography (FA)-detected microaneurysms. We investigated whether multiple image averaging could enhance the microaneurysm detection capability of OCTA in patients with DR.Prospective and cross-sectional observational study.Consecutive 31 patients (n = 62 eyes) with DR.All eyes underwent FA and 3 × 3 mm fovea-centered OCTA images were obtained using 2 devices: RTVue XR Avanti (Optovue Inc, Fremont, CA) and OCT HS-100 (Canon Inc, Toyko, Japan). OCTA imaging (HS-100) was performed 10 consecutive times. Microaneurysm detection capability was compared among 5 OCTA images (single image, ×3, ×5, and ×10 averaged images and single scan image with the RTVue XR Avanti device).Microaneurysm detection capability and the correlation between microaneurysm clinical characteristics or morphology and the extent of image averaging required for OCTA detection.A total of 415 microaneurysms could be analyzed in 31 eyes from 25 patients. Microaneurysms detected on single image, ×3, ×5, and ×10 averaged OCTA images were 144 (34.7%), 227 (54.7%), 285 (68.7%), and 306 (73.7%), respectively. Microaneurysm detection capability was significantly increased with increased image averaging. Microaneurysm detection with OCTA was not correlated with retinal thickness, FA leakiness, and indocyanine green angiogram detection or the number of averaged images, whereas there was significant correlation between microaneurysm morphology and microaneurysm visibility by the image-averaging process for 4 morphologies, particular the focal bulge types (P0.01).In DR, multiple image averaging is useful for increasing the microaneurysm detection capability of OCTA, especially for focal bulge-type microaneurysms.

Neural vascular barrier maintains the optimal tissue microenvironment of central nervous system in which neural cells can function normally. In various neural diseases, the decrease in oxygen concentration, hypoxia, of affected tissues is known to accelerate the disease progression through disruption of neural vascular barrier. Therefore, the clarification of mechanisms underlying hypoxia-induced disruption of neural vascular barrier would definitely lead to the establishment of new effective therapies for intractable neural diseases. In the present study, we first found that hypoxia disrupts neural vascular barrier through pathways independent of HIF-1α and HIF-2α. Then, with a specific fluorescence probe for ferrous, Fe(II) ion, we have obtained the interesting data showing that hypoxia increased the intracellular level of Fe(II) ion in endothelial cells of our in vitro model for neural vascular barrier, and that hypoxia-induced disruption of neural vascular barrier could be inhibited by chelating Fe(II) ion in endothelial cells. Furthermore, in the presence of a reducing reagent for reactive oxygen species (ROS), hypoxia could not disrupt the neural vascular barrier despite that the hypoxic increase in intracellular level of Fe(II) ion was confirmed in endothelial cells. These results indicate that hypoxia-triggered increase in the level of intracellular Fe(II) ion and subsequent production of ROS, probably through Fenton reaction, are the essential pathway mediating the disruption of neural vascular barrier under hypoxia.

Retinopathy of prematurity (ROP), a vascular proliferative disease affecting preterm infants, is a leading cause of childhood blindness. Various studies have investigated the pathogenesis of ROP. Clinical experience indicates that oxygen levels are strongly correlated with ROP development, which led to the development of oxygen-induced retinopathy (OIR) as an animal model of ROP. OIR has been used extensively to investigate the molecular mechanisms underlying ROP and to evaluate the efficacy of new drug candidates. Large clinical trials have demonstrated the efficacy of anti-vascular endothelial growth factor (VEGF) agents to treat ROP, and anti-VEGF therapy is presently becoming the first-line treatment worldwide. Anti-VEGF therapy has advantages over conventional treatments, including being minimally invasive with a low risk of refractive error. However, long-term safety concerns and the risk of late recurrence limit this treatment. There is an unmet medical need for novel ROP therapies, which need to be addressed by safe and minimally invasive therapies. The recent progress in biotechnology has contributed greatly to translational research. In this review, we outline how basic ROP research has evolved with clinical experience and the subsequent emergence of new drugs. We discuss previous and ongoing trials and present the candidate molecules expected to become novel targets.

Purpose Our purpose is to evaluate the spatial bias of macular capillary dropout accompanying diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA). Methods This study included 47 patients with diabetes and 29 healthy individuals who underwent OCTA. Retinal capillary flow density (FD) of 2.6 × 2.6 or 5.2 × 5.2 mm foveal area as well as the four divided areas (superior, inferior, temporal, nasal) without a foveal avascular zone (FAZ) at the superficial capillary plexus and deep capillary plexus (DCP) were measured respectively using ImageJ and NI Vision. Spatial biases of FD (orientation bias ratio and hierarchical bias ratio) and the correlation between FAZ and FD were examined. Results OCTA showed focal capillary dropout in DR patients. The orientation bias of FD was significantly higher in NPDR compared to NDR in the DCP (P = 0.03). The hierarchical bias of FD was significantly shifted to a DCP dominance with progression of DR (P < 0.01). In addition, the FD and FAZ area were significantly inversely correlated in both plexus in DR patients but not in healthy subjects (P < 0.01). Conclusions Area-divided OCTA quantification shows the appearance of spatial biases of macular capillary dropout with the onset of DR, suggesting that DR-related macular capillary dropout occurs locally and randomly. Future studies are necessary to determine the clinical relevance of the spatial pattern of capillary dropout in DR.

To investigate the roles of P2X7 receptors (P2RX7) in the pathogenesis of experimental autoimmune uveoretinitis (EAU).Experimental.Either wild-type (P2rx7The severity of EAU in P2rx7The results suggest that P2RX7 is a novel preventative therapeutic target for uveitis as it suppresses the effector functions of both Th1 and Th17 cell responses.

sVisual loss caused by retinopathy of prematurity (ROP) will be prevented if treatment-requiring ROP (TR-ROP) can be predicted. In this retrospective study including 418 infants with ≤32 weeks of gestational age (GA) and/or ≤1500 grams of birthweight, we attempted to identify useful predictors. We also examined the efficiency of significant predictors compared with existing predictive models, ROPScore and CHOP model. Multivariable logistic regression analyses supported the following factors were useful for predicting TR-ROP from all infants and infants with any ROP: GA (odds ratio [OR], 0.47 and 0.48), history of late-onset circulatory collapse (LCC) (OR, 2.76 and 2.44) and use of continuous positive airway pressure (CPAP) at 35 weeks of postmenstrual age (OR, 3.78 and 4.50). The comparison of areas under receiver operating characteristic curves indicated the combination of LCC, CPAP and ROPScore was better than ROPScore to predict TR-ROP from all infants and infants with any ROP (P = 0.007 and 0.02) and the combination of LCC, CPAP and CHOP model was also better than CHOP model to predict TR-ROP from all infants and infants with any ROP (P = 0.01 and 0.02). Our results suggested infants with a history of LCC and a long CPAP support have a high incidence of TR-ROP.

Rho-associated kinase (Rho-kinase/ROCK) was originally identified as an effector protein of the G protein Rho. Its involvement in various diseases, particularly cancer and cardiovascular disease, has been elucidated, and ROCK inhibitors have already been applied clinically for cerebral vasospasm and glaucoma. Vitreoretinal diseases including diabetic retinopathy, age-related macular degeneration, and proliferative vitreoretinoapthy are still a major cause of blindness. While anti-VEGF therapy has recently been widely used for vitreoretinal disorders due to its efficacy, attention has been drawn to new unmet needs. The importance of ROCK in pathological vitreoretinal conditions has also been elucidated and is attracting attention as a potential therapeutic target. ROCK is involved in angiogenesis and hyperpermeability and also in the pathogenesis of various pathologies such as inflammation and fibrosis. It has been expected that ROCK inhibitors will become new molecular target drugs for vitreoretinal diseases. This review summarizes the recent progress on the mechanisms of action of ROCK and their applications in disease treatment.

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.

Histological studies from autopsy specimens have characterized hard exudates as a composition of lipid-laden macrophages or noncellular materials including lipid and proteinaceous substances (hyaline substances). However, the characteristics of hard exudates in living patients have not been examined due to insufficient resolution of existing equipment. In this study, we used adaptive optics scanning laser ophthalmoscopy (AO-SLO) to examine the characteristics of hard exudates in patients with retinal vascular diseases. High resolution imaging using AO-SLO enables morphological classification of retinal hard exudates into two types, which could not be distinguished either on fundus examination or by spectral domain optical coherence tomography (SD-OCT). One, termed a round type, consisted of an accumulation of spherical particles (average diameter of particles: 26.9 ± 4.4 μm). The other, termed an irregular type, comprised an irregularly shaped hyper-reflective deposition. The retinal thickness in regions with round hard exudates was significantly greater than the thickness in regions with irregular hard exudates (P = 0.02). This differentiation of retinal hard exudates in patients by AO-SLO may help in understanding the pathogenesis and clinical prognosis of retinal vascular diseases

Histological studies from autopsy specimens have characterized hard exudates as a composition of lipid-laden macrophages or noncellular materials including lipid and proteinaceous substances (hyaline substances). However, the characteristics of hard exudates in living patients have not been examined due to insufficient resolution of existing equipment. In this study, we used adaptive optics scanning laser ophthalmoscopy (AO-SLO) to examine the characteristics of hard exudates in patients with retinal vascular diseases. High resolution imaging using AO-SLO enables morphological classification of retinal hard exudates into two types, which could not be distinguished either on fundus examination or by spectral domain optical coherence tomography (SD-OCT). One, termed a round type, consisted of an accumulation of spherical particles (average diameter of particles: 26.9 ± 4.4 μm). The other, termed an irregular type, comprised an irregularly shaped hyper-reflective deposition. The retinal thickness in regions with round hard exudates was significantly greater than the thickness in regions with irregular hard exudates (P = 0.02). This differentiation of retinal hard exudates in patients by AO-SLO may help in understanding the pathogenesis and clinical prognosis of retinal vascular diseases.

Recent clinical observations have indicated that vascular endothelial growth factor (VEGF) is a key factor that stimulates the development of preretinal pathological neovascularization (NV). However, it has not been established how intraretinal physiological revascularization of hypoxic avascular areas is regulated. Our earlier study on the gene expression profile of hypoxic retinas in a mouse model of oxygen-induced retinopathy (OIR) showed that macrophage inflammatory protein-1β (MIP-1β) was the most upregulated protein. The purpose of this study was to investigate the role played by MIP-1β in recruiting bone marrow-derived monocyte lineage cells (BM-MLCs) in a mouse model of OIR. Our results showed that MIP-1β was upregulated, and its receptor, CCR5, was expressed in BM-MLCs in the hypoxic inner retina. Neutralizing Ab against MIP-1β reduced the infiltration of BM-MLCs into the OIR retinas and increased the avascular area and preretinal neovascular tufts. A very strong significant correlation was found between the area of the preretinal neovascular tufts and the avascular area, regardless of the extent of BM-MLC infiltration into the OIR retinas. Additional treatment with VEGF-A-neutralizing Ab showed that the MIP-1β-regulated pathological NV strongly depended on VEGF-A, which was probably secreted by the hypoxic avascular retinas. These results indicate that MIP-1β is involved in the recruitment of BM-MLCs, which have a significant role in the physiological revascularization of hypoxic avascular retinas. Overall, these findings indicate that the MIP-1β induction of BM-MLCs might possibly be used to promote intraretinal revascularization and thus prevent the abnormal NV in ischemic vision-threatening retinal diseases.

Purpose: To investigate the change in localization of recurrent or persistent macular edema (ME) secondary to branch retinal vein occlusion (BRVO) after a therapeutic intervention. Methods: Twenty-six eyes of 23 patients with recurrent or persistent ME secondary to BRVO were included in this retrospective case series. We analyzed the distance between the fovea and the top of the ME (fovea–ME top distance) and the ME area using optical coherence tomography before treatment and when ME recurred or persisted. Results: The fovea–ME top distance decreased from 1.8 ± 1.6 to 1.2 ± 1.3 mm (p = 0.008). The ME area also decreased from 11.9 ± 4.9 to 7.6 ± 5.0 mm2 (p = 0.0003). The retinal vascular leakage area correlated with the ME area in all eyes. Conclusion: The site of recurrent or persistent ME tends to shift toward the fovea. These results suggest that residual perifoveal vascular leakage might be the predominant cause of recurrent or persistent ME.

Neural vascular barrier is essential for the life of multicellular organisms and its impairment by tissue hypoxia is known to be a central of pathophysiology accelerating the progression of various intractable neural diseases. Therefore, the molecules involved in hypoxia-induced impairment of vascular barrier can be the targets to establish new therapies for intractable diseases. Here, we demonstrate that a disintegrin and metalloproteinases (ADAMs) 12 and 17 expressed in endothelial cells are the molecules responsible for the impairment of neural vascular barrier by hypoxia. Brain microvascular endothelial cells in vitro lost their barrier properties immediately after hypoxic stimulation through diminished localization of claudin-5, a tight junction molecule, on cell membranes. Hypoxic disappearance of claudin-5 from cell membranes and the consequent loss of barrier properties were completely suppressed by inhibition of the metalloproteinase activity which was found to be attributed to ADAM12 and ADAM17. Inhibition of either ADAM12 or ADAM17 was sufficient to rescue the in vivo neural vasculature under hypoxia from the loss of barrier function. This is the first report to specify the molecules which are responsible for hypoxia-induced impairment of neural vascular barrier and furthermore can be the targets of new therapeutic strategies for intractable neural diseases.

The choroid is an area of the eye commonly affected both by metastatic tumors and by primary malignant melanomas [1]. Although the accuracy of the clinical diagnosis of uveal melanoma has improved [2], atypical ocular manifestations may lead to misdiagnosis in some cases. In the case presented here, we observed choroidal metastasis with melanocytic proliferation that mimicked malignant choroidal melanoma.

Purpose In this study, we investigated the therapeutic potential of a Rho-associated coiled-coil-containing protein kinase (ROCK) inhibitor ripasudil (K-115) eye drop on retinal neovascularization and hypoxia. Methods In vitro, human retinal microvascular endothelial cells (HRMECs) were pretreated with ripasudil and then stimulated with VEGF. ROCK activity was evaluated by phosphorylation of myosin phosphatase target protein (MYPT)-1. Endothelial migration and cell viability were assessed by cell migration and MTT assay, respectively. The concentration of ripasudil in the retina was measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). In vivo, normal saline, 0.4%, or 0.8% ripasudil were administered three times a day to mice with oxygen-induced retinopathy (OIR). The areas of neovascularization and avascular retina were also quantified with retinal flat-mounts at postnatal day (P) 15, P17, or P21. The retinal hypoxic area was evaluated using hypoxia-sensitive drug pimonidazole by immunohistochemistry at P17. The vascular normalization was also evaluated by immunohistochemistry at P17. Results Ripasudil but not fasudil significantly reduced VEGF-induced MYPT-1 phosphorylation in HRMECs at 30 μmol/L. Ripasudil significantly inhibited VEGF-induced HRMECs migration and proliferation. The concentration of ripasudil in the retina was 3.8 to 10.4 μmol/L and 6.8 to 14.8 μmol/L after 0.4% and 0.8% ripasudil treatment, respectively. In the 0.4% and 0.8% ripasudil treated OIR mice, the areas of neovascularization as well as avascular area in the retina was significantly reduced compared with those of saline-treated mice at P17 and P21. Pimonidazole staining revealed that treatment with 0.4% and 0.8% ripasudil significantly inhibited the increase in the hypoxic area compared with saline. 0.8% ripasudil could cause intraretinal vascular sprouting and increase retinal vascular perfusion. Conclusions Novel ROCK inhibitor ripasudil eye drop has therapeutic potential in the treatment of retinal hypoxic neovascular diseases via antiangiogenic effects as well as vascular normalization.

Purpose A timely regression of the hyaloid vascular system (HVS) is required for the normal ocular development. Although macrophages have a critical role in this process, the exact mechanism remains undetermined. Periostin is a matricellular protein involved in tissue and vascular remodeling. The purpose of our study was to determine whether periostin is involved in the HVS regression. Methods We used wild type (WT) and periostin knockout (KO) mice. Indocyanine green angiography and immunohistochemistry with isolectin B4 were used to evaluate the HVS regression. TUNEL-labeling was used to quantify the number of apoptotic hyaloid vascular endothelial cells. F4/80 and Iba-1 staining was performed to determine the number and location of macrophages in the vitreous. The location of periostin also was investigated by immunohistochemistry. To determine the functional role of periostin, the degree of adhesion of human monocytes to fibronectin was measured by an adhesion assay. Results The HVS regression and peak in the number of TUNEL-positive apoptotic endothelial cells were delayed in periostin KO mice. The number of F4/80 positive cells in the vitreous was higher in periostin KO mice. Only a small number of Iba-1-positive cells near the hyaloid vessels was co-stained with periostin, and peripheral blood monocytes were not stained with periostin. Adhesion assay showed that periostin increased the degree of attachment of monocytes to fibronectin. Conclusions These results suggest that periostin, which is secreted by the intraocular macrophages, enhances the HVS regression by intensifying the adhesion of macrophages to hyaloid vessels.

PURPOSE. Anti–VEGF-A antibody (Ab) (e.g., bevacizumab, ranibizumab) is widely used as a treatment against retinal angiogenesis and edema. The purpose of this study was to evaluate whether intravitreal anti-VEGF Ab injection modulates inflammatory cells in retinal angiogenesis. METHODS. To investigate whether intravitreal bevacizumab injections affect the number of inflammatory cells in proliferative diabetic retinopathy (PDR) membranes in patients, immunohistochemical staining with CD45 Ab (pan-leukocyte marker) was performed using the surgically obtained membranes in pars plana vitrectomy with or without pretreatment with bevacizumab. To check whether anti–VEGF-A Ab affects leukocytes going in and out of blood vessels during retinal angiogenesis, the authors performed their novel leukocyte transmigration assay and CD45 immunostaining in a mouse model of oxygen-induced retinopathy (OIR). RESULTS. The authors’ new imaging approach revealed that intravitreal injection of anti–VEGF-A Ab blocks leukocyte infiltration as well as angiogenesis. The Ab injection inhibited leukocyte transmigration before affecting the angiogenenic area. CD45 staining showed no significant difference in the leukocyte number in the angiogenic retina or the human PDR membranes between the anti–VEGF-A Ab injected group and the control group. Furthermore, VEGF-A inhibition also affected leukocytes going out from the retina. CONCLUSIONS. Intravitreal injection of anti-VEGF-A Ab could inhibit leukocyte trafficking in the retina, suggesting that antiVEGF-A therapy could serve as a treatment in retinal inflammation. (Invest Ophthalmol Vis Sci. 2012;53:4323– 4328) DOI:10.1167/iovs.11-9119

Diabetic retinopathy (DR) is one of the leading causes of decreased vision and blindness in industrialized countries (Bhavsar, 2002). Much of the retinal damage that characterizes advanced proliferative diabetic retinopathy (PDR) results from retinal neovascularization (Simo, et al., 2006). When the newly formed vessels are associated with fibrous proliferations that form fibrovascular membranes (FVMs) on the surface of the neuroretina, traction retinal detachments can develop, resulting in potentially severe loss of vision (Hiscott, et al., 2000).

PURPOSE. Preretinal fibrovascular membranes (FVMs) form as a sequela to proliferative diabetic retinopathy (PDR), and their presence can lead to a severe decrease of vision. The purpose of this study was to determine whether periostin, a matricellular protein that plays a role in cell adhesion and migration, is associated with the formation of FVMs. METHODS. One hundred six vitreous samples and 15 FVMs were obtained during vitrectomy on patients with PDR. Semiquantitative RT-PCR was performed to determine the periostin level of the mRNA. Immunohistochemical analyses were performed to determine the sites of periostin expression in the FVMs. ELISA was used to measure the concentrations of periostin, bFGF, and VEGF in the vitreous. RESULTS. The periostin level of the mRNA was high in 10 of 10 FVMs tested but was barely detectable in the control retinas. Sequencing of the periostin PCR products revealed three splice variants of the FVMs. Immunohistochemical analysis showed colocalization of periostin and -SMA in FVM cells. The concentration of periostin in the vitreous was significantly higher in patients with PDR than in the 31 eyes of patients with a macular hole or an epiretinal membrane (P 0.001). Among the PDR patients, the mean vitreous level of periostin in eyes with FVMs was significantly higher than in those without FVMs (epicenter only; P 0.001). The correlation between the vitreous concentrations of periostin and of bFGF and VEGF was not significant. CONCLUSIONS. These findings indicate that periostin may be involved in the development of FVMs. (Invest Ophthalmol Vis Sci. 2011;52:5670‐5678) DOI:10.1167/iovs.10-6625

Anatomical closure of macular holes (MH) is now largely confirmed by optical coherence tomography (OCT). Fundus autofluorescence (FAF) is also helpful in diagnosis and anatomical estimation of MH. We report a case of early reopening of anatomically closed MH, 2 days after release from face-down positioning where FAF abnormalities proceeded OCT findings.A case report. A 67-year-old woman underwent vitrectomy with brilliant blue G-assisted ILM peeling for the treatment of full-thickness stage 4 MH (diameter 578 microm). FAF and OCT were used to evaluate the patient.On post operative day 3, OCT showed anatomical closure of MH, but FAF persistently demonstrated hyperfluorescence in the fovea. On post operative day 5, 2 days after termination of positioning, OCT showed reopening of the MH. Intra-vitreous injection of 50 % sulfur hexafluoride (SF(6)) gas was performed followed by face-down positioning again. Fourteen days after surgery, we confirmed the findings of both the anatomical closure in OCT and hypofluorescence on FAF. Two months later, MH remained closed.FAF might be a useful measure as a supportive method to guide release from posture restriction.