TNFRSF10A downregulation induces retinal pigment epithelium degeneration during the pathogenesis of age-related macular degeneration and central serous chorioretinopathy.

Age-related macular degeneration (AMD) and central serous chorioretinopathy (CSC) are common diseases that can cause vision loss in older and younger populations. These diseases share pathophysiological conditions derived from retinal pigment epithelium (RPE) dysfunction. Tumor necrosis factor receptor superfamily 10A (TNFRSF10A)-LOC389641 with the same lead single-nucleotide polymorphism (SNP) (rs13278062) is the only overlapped susceptibility locus found in both AMD and CSC through genome-wide association studies. This lead SNP has been reported to alter the transcriptional activity of TNFRSF10A. This study aimed to elucidate the function of TNFRSF10A in RPE degeneration using human primary RPE cells and Tnfrsf10 knockout (Tnfrsf10-/-) mice. TNFRSF10A was found to be localized in human RPE. In vitro assays revealed that a T allele of rs13278062, the risk allele for AMD and CSC, downregulated TNFRSF10A transcription in RPE, leading to decreased cell viability and increased apoptosis through protein kinase C-α (PKCA) downregulation. Treatment with phorbol 12-myristate 13-acetate, a PKC activator, rescued the cell viability. Morphological RPE abnormality was found in the retina of Tnfrsf10-/- mice. Our data suggest that downregulation of TNFRSF10A expression inactivates PKCA signaling and causes cellular vulnerability of the RPE, which may contribute to the pathogenesis of AMD and CSC.

Relationships between causative genes and epiretinal membrane formation in Japanese patients with retinitis pigmentosa.

PURPOSE: To investigate the relationships between macular complications and causative genes frequently found in Japanese patients with retinitis pigmentosa (RP). METHODS: In the retrospective and observational study, we analyzed the data of 75 patients with RP (EYS-RP: 42 patients; USH2A-RP: 19 patients; RHO-RP: 14 patients) who were followed-up at Kyushu University Hospital and whose causative genes had been identified. Macular complications including epiretinal membrane (ERM), macular edema (ME), and macular hole (MH) were evaluated using optical coherence tomography and fundus photography. Main outcome was the proportion of macular complications. RESULTS: The proportion of ERM was 35.7% in the EYS group, 10.5% in the USH2A group and 14.3% in the RHO group. The proportion of ME was 7.1% in the EYS group, 5.3% in the USH2A group and 14.3% in the RHO group, and that of MH was 2.4% in the EYS group, 5.3% in the USH2A group and 0% in the RHO group. In the EYS group, the proportion of ERM was relatively higher (p = 0.06), and the presence of EYS was significantly associated with a higher age- and sex-adjusted OR for ERM (OR = 5.67, 95% CI = 1.59-25.20). There was no significant difference in the proportion of MH or ME among causative genes. CONCLUSIONS: EYS causative gene may be associated with higher rate of ERM complication in RP.

Three-month outcomes of treatment with faricimab or aflibercept for neovascular age-related macular degeneration: a propensity score matching study in a Japanese population.

PURPOSE: This study aimed to compare the treatment outcomes of patients with neovascular age-related macular degeneration (nAMD) who initially received faricimab or aflibercept treatment using propensity score matching (PSM) to align patient backgrounds. METHODS: Patients with treatment-naïve nAMD who received either faricimab or aflibercept for three consecutive monthly injections as the loading phase were enrolled in this study. In the 1:1 PSM, sex, age, best-corrected visual acuity (BCVA), central macular thickness (CMT), central choroidal thickness (CCT), and AMD subtypes in the pre-treatment state were selected as covariates. We examined the BCVA, CMT, CCT, and remaining fluid at 1-, 2-, and 3-month after the first injection. RESULTS: After PSM, 43 eyes were included in the faricimab and aflibercept group each. Both groups showed significant improvements in BCVA, CMT, and CCT at 1-, 2-, and 3-month after the initial injection compared with baseline. Meanwhile, no significant differences were observed between the two groups at any time point regarding BCVA, CMT, and CCT. At 1-month, 18.6% of patients in the faricimab group and 41.9% in the aflibercept group demonstrated residual subretinal fluid or intraretinal fluid, with a significant difference between the groups (P = 0.03). CONCLUSION: The BCVA improved after three loading injections of both faricimab and aflibercept. Faricimab may provide a favorable early treatment response in reducing subretinal fluid in a Japanese cohort.

IMPACT OF MACULAR INTRARETINAL HEMORRHAGE AND MACULAR HOLE ON THE VISUAL PROGNOSIS OF SUBMACULAR HEMORRHAGE DUE TO RETINAL ARTERIAL MACROANEURYSM RUPTURE.

PURPOSE: To compare the effects of macular intraretinal hemorrhage (IRH) and macular hole (MH) on best-corrected visual acuity (BCVA) after displacement of submacular hemorrhage (SMH) due to retinal arterial macroaneurysm (RAM) rupture. METHODS: This multicenter retrospective study included 48 eyes with SMH due to RAM rupture. Cases underwent vitrectomy to displace SMH and were followed up for 6 months. We classified cases according to the presence of IRH and MH and compared the postoperative BCVA among the groups. RESULTS: We classified the eyes into IRH(+)MH(+) group (10 eyes), IRH(+)MH(-) group (23 eyes), and IRH(-)MH(-) group (15 eyes). The postoperative BCVA was significantly worse in the IRH(+)MH(+) and IRH(+)MH(-) groups than in the IRH(-)MH(-) group (0.91 ± 0.41 in logarithm of the minimal angle of resolution units, Snellen equivalent 20/163, 0.87 ± 0.45, 20/148, and 0.18 ± 0.21, 20/30, respectively; P < 0.001). The postoperative central retinal thickness was significantly lower in the IRH(+) group (IRH(+)MH(+) and IRH(+)MH(-) groups combined) than in the IRH(-) group (IRH(-)MH(-) group) (121.4 ± 70.1 µ m and 174.3 ± 32.9 µ m, respectively, P = 0.008). The postoperative external limiting membrane and ellipsoid zone continuities were significantly discontinuous in the IRH(+) group ( P < 0.001, P = 0.001, respectively). The multiple linear regression analysis showed that both IRH(+)MH(+) and IRH(+)MH(-) were associated with the postoperative BCVA (regression coefficient, 0.799 and 0.711, respectively; P < 0.001 for both). CONCLUSION: Both IRH and MH were poor prognostic indicators in cases with SMH due to RAM rupture.

Development of in situ crosslinked hyaluronan as an adjunct to vitrectomy surgery.

Ophthalmologists have used hyaluronan (HA) products as adjuncts to ocular surgery since the 1970s. However, HA products are not always functional in surgeries of the posterior eye segment due to their lack of biomechanical strength. In this study, we developed an in situ crosslinked HA (XL-HA) and evaluated its potential as an adjunct to vitrectomy surgery in an in vitro model with a triamcinolone acetonide (TA) layer used as a pseudo residual vitreous cortex (RVC). Within a few minutes at concentrations over 0.9%, XL-HA, generated by the click chemistry of HA-dibenzocyclooctyne and HA-azidoethylamine, formed a hydrogel with the appropriate hardness for tweezers peeling. XL-HA (concentration, 0.76-1.73%) without dispersion successfully entered the TA layer and removed more than 45% of the total TA. Dynamic viscoelasticity helps to explain the rheological behavior of hydrogels, and the assessment results for XL-HA indicated that suitable concentrations were between 0.97% and 1.30%. For example, 1.30% XL-HA hydrogel reached sufficient hardness at 3 min for tweezers peeling, and the TA removal ability exceeded 70%. These results demonstrated that XL-HA was a potential adjunct to successful vitrectomy.

Increased vitreous levels of B cell activation factor (BAFF) and soluble interleukin-6 receptor in patients with macular edema due to uveitis related to Behçet's disease and sarcoidosis.

PURPOSE: Uveitis accounts for 10-15% of all cases of blindness in the developed world. Uveitic macular edema (UME) is a primary cause of permanent visual impairment in patients with uveitis. Because proinflammatory mediators elicit inflammation and lead to UME, we determined the profiles of proinflammatory mediators associated with complications, such as ME, in the vitreous humor of patients with panuveitis related to Behçet's disease (BD) and sarcoidosis. METHODS: In this retrospective study, we enrolled 21 patients with uveitis, including 6 with BD and 15 with sarcoidosis, and 15 patients with idiopathic epiretinal membrane (iERM) at the Department of Ophthalmology, Kyushu University Hospital, between January 2008 and April 2016. Vitreous concentrations of 32 proinflammatory mediators, including cytokines and soluble receptors of tumor necrosis factor (TNF) and interleukin (IL)-6 families, were assessed using a bead-based multiplex assay and their association with clinical data was examined. RESULTS: The levels of proinflammatory mediators, including a proliferation-inducing ligand (APRIL), B cell activating factor belonging to the TNF family (BAFF), soluble cluster of differentiation 30 (sCD30), soluble TNF receptor-1 (sTNFR1), sTNFR2, TNF-α, IL-6, and soluble IL-6 receptor-α (sIL-6Rα), were significantly higher in patients with uveitis. With regard to clinical parameters in patients with uveitis, vitreous levels of BAFF and sIL-6Rα were prominently elevated in patients with UME compared to in those without UME (P < 0.01, respectively). CONCLUSIONS: Our results suggest that elevated vitreous levels of BAFF and sIL-6Rα are associated with the pathogenesis of UME in patients with panuveitis related to BD and sarcoidosis.

Genetic LAMP2 deficiency accelerates the age-associated formation of basal laminar deposits in the retina.

The early stages of age-related macular degeneration (AMD) are characterized by the accumulation of basal laminar deposits (BLamDs). The mechanism for BLamDs accumulating between the retinal pigment epithelium (RPE) and its basal lamina remains elusive. Here we examined the role in AMD of lysosome-associated membrane protein-2 (LAMP2), a glycoprotein that plays a critical role in lysosomal biogenesis and maturation of autophagosomes/phagosomes. LAMP2 was preferentially expressed by RPE cells, and its expression declined with age. Deletion of the Lamp2 gene in mice resulted in age-dependent autofluorescence abnormalities of the fundus, thickening of Bruch's membrane, and the formation of BLamDs, resembling histopathological changes occurring in AMD. Moreover, LAMP2-deficient mice developed molecular signatures similar to those found in human AMD-namely, the accumulation of APOE, APOA1, clusterin, and vitronectin-adjacent to BLamDs. In contrast, collagen 4, laminin, and fibronectin, which are extracellular matrix proteins constituting RPE basal lamina and Bruch's membrane were reduced in Lamp2 knockout (KO) mice. Mechanistically, retarded phagocytic degradation of photoreceptor outer segments compromised lysosomal degradation and increased exocytosis in LAMP2-deficient RPE cells. The accumulation of BLamDs observed in LAMP2-deficient mice was eventually followed by loss of the RPE and photoreceptors. Finally, we observed loss of LAMP2 expression along with ultramicroscopic features of abnormal phagocytosis and exocytosis in eyes from AMD patients but not from control individuals. Taken together, these results indicate an important role for LAMP2 in RPE function in health and disease, suggesting that LAMP2 reduction may contribute to the formation of BLamDs in AMD.

Decrease in the number of microaneurysms in diabetic macular edema after anti-vascular endothelial growth factor therapy: implications for indocyanine green angiography-guided detection of refractory microaneurysms.

PURPOSE: We evaluated changes in the numbers of microaneurysms (MAs) on fluorescein angiography (FA) and indocyanine green angiography (IA) in eyes with diabetic macular edema (DME) following intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents. METHODS: Twenty-one eyes of 16 patients with DME were included in this retrospective study. All patients received an initial loading dose of three monthly injections of anti-VEGF agents; thereafter, they received a pro re nata regimen for at least 12 months of follow-up. FA and IA images were obtained before and at 6 months after the initial injection. RESULTS: The median numbers of MAs significantly decreased from six (interquartile range [IQR] 3-7) MAs in early-phase FA, three (IQR 3-5) leaky MAs in late-phase FA, and two (IQR 1-4) MAs in late-phase IA at baseline to two (IQR 1-3) MAs in early-phase FA, one (IQR 0-2) leaky MA in late-phase FA, and one (IQR 0-2) MA in late-phase IA at 6 months (P < 0.0001 for all). Only the median numbers of MAs in late-phase IA at baseline and at 6 months were significantly higher in the recurrent DME group (13 eyes) than in the non-recurrent DME group (five eyes) (three [IQR 2-4] vs one [IQR 1-2], one [IQR 0.5-2] vs zero [P = 0.0185 and P = 0.009]). CONCLUSION: Intravitreal injection of anti-VEGF agents reduced the numbers of MAs in patients with DME. The numbers of MAs detected by late-phase IA might be useful predictors of DME recurrence.

Development of a novel noninvasive system for measurement and imaging of the arterial phase oxygen density ratio in the retinal microcirculation.

PURPOSE: This study was conducted in order to develop a novel noninvasive system for measurement and imaging of the arterial oxygen density ratio (ODR) in the retinal microcirculation. METHODS: We developed a system composed of two digital cameras with two different filters, which were attached to a fundus camera capable of simultaneously obtaining two images. Actual measurements were performed on healthy volunteer eyes (n = 61). A new algorithm for ODR measurement and pixel-level imaging of erythrocytes was constructed from these data. The algorithm was based on the morphological closing operation and the line convergence index filter. For system calibration, we compared and verified the ODR values in arterioles and venules that were specified in advance for 56 eyes with reproducibility. In 10 additional volunteers, ODR measurements and imaging of the arterial phase in the retinal microcirculation corresponding to changes in oxygen saturation of the peripheral arteries at normal breathing and breath holding were performed. RESULTS: Estimation of incident light to erythrocytes and pixel-level ODR calculation were achieved using the algorithm. The mean ODR values of arterioles and venules were 0.77 ± 0.060 and 1.02 ± 0.067, respectively. It was possible to separate these regions, calibrate at the pixel level, and estimate the arterial phase. In each of the 10 volunteers, changes in the arterial phase ODR corresponding to changes in oxygen saturation of the peripheral arteries were observed before and after breath holding on ODR images. The mean ODR in 10 volunteers was increased by breath holding (p < 0.05). CONCLUSIONS: We developed a basic system for arterial phase ODR measurement and imaging of the retinal microcirculation. With further validation and development, this may provide a useful tool for evaluating retinal oxygen metabolism in the retinal microcirculation.

Retinal flow density by optical coherence tomography angiography is useful for detection of nonperfused areas in diabetic retinopathy.

PURPOSE: Fluorescein angiography (FA) has been conventionally used for detection of retinal nonperfused area (NPA) in diabetic retinopathy (DR) in spite of its qualitative evaluation. Optical coherence tomography angiography (OCTA) has been recently reported to be useful for the quantification of retinal vascular disorder in DR. In this study, we examined whether retinal flow density (FD) measurement in OCTA was useful for NPA detection in DR. METHODS: The study included 41 eyes from 29 patients with DR who underwent FA and OCTA. Regions surrounded by arteries or veins were extracted in the OCTA image, and the FDs in each region were measured by Image J. Furthermore, each region was classified as NPA or perfused area (PA) in FA. The receiver operating characteristic (ROC) curve was prepared by logistic regression analysis of the FD. The AUC (area under the ROC curve) and cutoff value of FD were also calculated. RESULTS: Two hundred fifty-two regions were analyzed and classified into 38 NPA regions and 214 PA regions using FA. FD of each capillary plexus in NPA was significantly smaller than in PA (p < 0.0001). The AUC of total capillary plexus layers (TCP), superficial capillary plexus layer (SCP), and deep capillary plexus layer (DCP) was 0.975, 0.974, and 0.971, respectively. All areas, where the FD was more than the cutoff value (0.07 in TCP), were diagnosed with PA. Three areas with intraretinal microvascular abnormalities (IRMA) were diagnosed as PA despite being below the cutoff value. CONCLUSIONS: FD measurement in OCTA is useful for NPA detection in DR.

INTERNAL LIMITING MEMBRANE PEELING-DEPENDENT RETINAL STRUCTURAL CHANGES AFTER VITRECTOMY IN RHEGMATOGENOUS RETINAL DETACHMENT.

PURPOSE: To examine retinal changes after vitrectomy with internal limiting membrane (ILM) peeling, we used 3-dimensional optical coherence tomography (3D-OCT) in rhegmatogenous retinal detachment cases. METHODS: The 68 eyes from 67 patients with rhegmatogenous retinal detachment were studied, including 35 detached macula cases (51%) and 33 attached macula cases. Internal limiting membrane peeling was performed with fine forceps after brilliant blue G staining. The 3D-OCT images were obtained with volume-rendering technologies from cross-sectional OCT images. RESULTS: The 3D-OCT detected 45 eyes (66%) with ILM peeling-dependent retinal changes, including dissociated optic nerve fiber layer appearance, dimple sign, temporal macular thinning, ILM peeling area thinning, or forceps-related retinal thinning. The ILM peeled area was detectable in only 9 eyes with 3D-OCT, whereas it was undetectable in other 59 eyes. The dissociated optic nerve fiber layer appearance was detected in 8 of the total cases (12%), and dimple signs were observed in 14 cases (21%). Forceps-related thinning was also noted in eight cases (24%) of attached macula cases and in four cases (11%) of detached macula cases. No postoperative macular pucker was noted in the observational period. CONCLUSION: The 3D-OCT clearly revealed spatial and time-dependent retinal changes after ILM peeling. The changes occurred in 2 months and remained thereafter.

Visual Outcomes Based on Early Response to Anti-Vascular Endothelial Growth Factor Treatment for Diabetic Macular Edema.

OBJECTIVE: To examine the relationship between early response to anti-vascular endothelial growth factor (VEGF) treatment and visual prognosis. METHODS: We retrospectively separated 20 patients with persistent diabetic macular edema (DME) into two responder status groups based on the reduction of central macular thickness (CMT) from baseline to month 3: a delayed responder group (DRG) (≤25% CMT reduction, n = 11) and an immediate responder group (IRG) (>25% CMT reduction, n = 14). We also separated the patients into two responder status groups based on the logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA): a visual nonimprovement group (VNIG) (≥0 logMAR BCVA improvement, n = 11) and a vi sual improvement group (VIG) (<0 logMAR BCVA improvement, n = 14). Finally, we assessed the correlations between logMAR BCVA changes from baseline to month 3 (ΔBCVAM3) and those from baseline to month 12 (ΔBCVAM12). RESULTS: At month 12, BCVA was significantly more improved in the VIG than the VNIG (p < 0.005), but was not significantly different between the DRG and the IRG (p = 0.75). The Pearson correlation coefficient showed a significant relationship between ΔBCVAM3 and ΔBCVAM12 (r = 0.60, p < 0.005). CONCLUSIONS: BCVA showed significantly greater improvement in the VIG than in the VNIG. ΔBCVAM3 may predict the visual outcome at month 12 in DME patients treated with anti-VEGF drugs.

INCOMPLETE REPAIR OF RETINAL STRUCTURE AFTER VITRECTOMY WITH INTERNAL LIMITING MEMBRANE PEELING.

PURPOSE: To examine retinal changes after vitrectomy with internal limiting membrane (ILM) peeling, we used a cynomolgus monkey model and focused on surgical damages of ILM peeling for long observational period of 3 years. METHODS: Vitrectomy was performed followed by ILM peeling similar to clinical settings in humans. Ultrastructural changes of the retina were investigated by light, transmission, and scanning electron microscopy at 3 months and 3 years after ILM peeling. RESULTS: Ultrastructural study showed that the ILM peeled area was still clearly recognized after 3 years. The Müller cell processes covered most of the retina; however, the nerve fiber layer was partly uncovered and exposed to the vitreous space. The arcuate linear nerve fiber bundles were observed as comparable with dissociated optic nerve fiber layer appearance. Small round retinal surface defects were also observed around macula, resembling the dimple sign. Forceps-related retinal thinning was also found on the edge of ILM peeling, where we started peeling with fine forceps. CONCLUSION: The ultrastructural studies showed that most of ILM peeling area was covered with glial cells during wound healing processes. Retinal changes were found comparable with dissociated optic nerve fiber layer appearance or dimple sign, which were clinically observed with optical coherence tomography.

PERMEABILITY AND ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR EFFECTS OF BEVACIZUMAB, RANIBIZUMAB, AND AFLIBERCEPT IN POLARIZED RETINAL PIGMENT EPITHELIAL LAYER IN VITRO.

PURPOSE: To determine the effects of bevacizumab, ranibizumab, and aflibercept on the permeability and the effects of anti-vascular endothelial growth factor (VEGF) on highly polarized retinal pigment epithelial cells (RPECs) in vitro. METHODS: Highly polarized RPECs were cultured in the upper chamber of a Transwell system. Anti-VEGF antibodies were added to the upper chamber, and the concentrations of the drugs in the lower chambers were measured. The permeability rates of the three anti-VEGF drugs through the RPEC layer and the concentration of VEGF in each chamber were determined. RESULTS: The permeability of aflibercept was significantly lower by about 40% than that of bevacizumab through the RPEC layer (P < 0.05). Ranibizumab was significantly more permeable through the RPECs than bevacizumab (180% of bevacizumab, P < 0.05). Although VEGF was almost absent in the upper chamber after exposure to the 3 antibodies, it was decreased more significantly with aflibercept than with bevacizumab in the lower chamber (2.8% vs. 65.8% of control; P < 0.01). Ranibizumab also decreased the VEGF level compared with bevacizumab (31.7% vs. 65.8% of control; P < 0.01). CONCLUSION: The greater reduction of the amount of VEGF in the lower chamber by aflibercept and ranibizumab than bevacizumab may explain why aflibercept and ranibizumab are more effective than bevacizumab against type 1 choroidal neovascularization.

Tenascin-C secreted by transdifferentiated retinal pigment epithelial cells promotes choroidal neovascularization via integrin αV.

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-ß2 increased tenascin-C expression in hRPE cells. Conditioned media harvested from TGF-ß2-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.

Tenascin-C promotes angiogenesis in fibrovascular membranes in eyes with proliferative diabetic retinopathy.

PURPOSE: We previously demonstrated that tenascin-C was highly expressed in the fibrovascular membranes (FVMs) of patients with proliferative diabetic retinopathy (PDR). However, its role in the pathogenesis of FVMs has not been determined. The purpose of this study was to investigate what role tenascin-C plays in the formation and angiogenesis of FVMs. METHODS: The level of tenascin-C was determined by sandwich enzyme-linked immunosorbent assay in the vitreous samples collected from patients with PDR and with a macular hole as control. The locations of tenascin-C, α- smooth muscle actin (SMA), CD34, glial fibrillary acidic protein (GFAP), and integrin αV in the FVMs from PDR patients were determined by immunohistochemistry. We also measured the in vitro expression of the mRNA and protein of tenascin-C in vascular smooth muscle cells (VSMCs) stimulated by interleukin (IL)-13. The effects of tenascin-C on cell proliferation, migration, and tube formation were determined in human retinal endothelial cells (HRECs) in culture. RESULTS: The mean vitreous levels of tenascin-C were significantly higher in patients with PDR than in patients with a macular hole (p<0.001). Double immunofluorescence analyses of FVMs from PDR patients showed that tenascin-C co-stained FVMs with α-SMA, CD34, and integrin αV but not with GFAP. In addition, IL-13 treatment increased both the expression and secretion of tenascin-C by VSMCs in a dose-dependent manner. Tenascin-C exposure promoted proliferation, migration, and tube formation in HRECs. Tenascin-C neutralizing antibody significantly blocked the tube formation by HRECs exposed to VSMC-IL-13-conditioned medium. CONCLUSIONS: Our findings suggest that tenascin-C is secreted from VSMCs and promotes angiogenesis in the FVMs associated with PDR.

Factors affecting visual acuity after cataract surgery in patients with retinitis pigmentosa.

PURPOSE: To investigate the factors affecting visual acuity after cataract surgery in patients with retinitis pigmentosa (RP). DESIGN: Retrospective, observational study. PARTICIPANTS: We retrospectively reviewed the charts of a consecutive series of 40 patients with RP who underwent cataract surgery. METHODS: The changes in preoperative and postoperative best-corrected visual acuity (BCVA) were measured. We investigated the relation between preoperative mean deviation (MD) value on the Humphrey Field Analyzer (HFA: the central 10-2 program; Humphrey Instruments, Inc, San Leandro, CA) and final BCVA. We also investigated the relationship between preoperative ellipsoid zone (EZ; also called the inner/outer segment junction) conditions and final BCVA. In addition, we showed the prevalence of macular complications and capsule complications. MAIN OUTCOME MEASURES: The BCVA, slit-lamp biomicroscopic analysis, visual field, and optical coherence tomography (OCT) were obtained. RESULTS: The mean of the BCVA significantly improved after cataract surgery from 0.76 (range, -0.08 to 2.30) to 0.45 (range, -0.18 to 2.00) (P < 0.005). However, final BCVA did not improve in 30 eyes (53.6%). The preoperative MD value and the final BCVA were significantly correlated, and the final BCVA significantly improved in the less advanced RP group (MD was ≥-15 decibels [dB]). The final BCVA was significantly better in the group in which preoperative OCT showed a normal EZ than in the groups in which the EZ was abnormal or not visible. Posterior capsular opacification was observed in 47 eyes (83.9%), and 23 eyes (41.1%) underwent YAG laser capsulotomy within a mean follow-up time of 3 years. CONCLUSIONS: Final BCVA in approximately half of the eyes improved after cataract surgery in patients with RP. The preoperative ophthalmic examinations that may reflect macular (or foveal) function, such as HFA 10-2 program and OCT, are important parameters to assess postoperative visual outcome.

Penetration of bevacizumab and ranibizumab through retinal pigment epithelial layer in vitro.

PURPOSE: To determine the permeability of bevacizumab and ranibizumab through highly-polarized retinal pigment epithelial (RPE) cells in vitro. METHODS: Highly-polarized RPE cells were cultured in the upper chamber of a Transwell culture system. Bevacizumab or ranibizumab was added to the upper chamber. After 3 hours, the concentrations of bevacizumab or ranibizumab were determined in the upper and lower chambers. The cytotoxicities of the two anti-vascular endothelial growth factor agents were determined histologically. The effects of inhibiting endocytosis by pharmacologic inhibitors were also evaluated. RESULTS: The concentration of ranibizumab was higher than that of bevacizumab in the lower chamber (P < 0.05). Vascular endothelial growth factor was found mainly in the lower chamber under normal conditions. However, the concentration of vascular endothelial growth factor in the lower chamber was significantly less when ranibizumab was added to the upper chamber than when bevacizumab was added. Histology showed no obvious changes in bevacizumab-exposed or ranibizumab-exposed RPE cells. Pretreatment with protein kinase C inhibitor staurosporine had significant negative effects on the permeability of bevacizumab and ranibizumab (P < 0.05). CONCLUSION: Ranibizumab is more permeable than bevacizumab through the highly-polarized RPE layer at clinically equivalent concentrations, and their permeability was partially protein kinase C-dependent. Ranibizumab might be more therapeutically effective than bevacizumab on choroidal neovascularization beneath the RPE layer.

Brilliant Blue G double staining enhances successful internal limiting membrane peeling with minimal adverse effect by low cellular permeability into live cells.

PURPOSE: Brilliant Blue G is used as a surgical adjuvant for retinal surgery. Although BBG double or multiple staining was reported, the effectiveness and safety of repeated staining is still elusive. To further examine the effectiveness and safety, we examined BBG in clinical cases in vivo, primary cell culture in vitro, and surgically resected specimen ex vivo. METHODS: A retrospective interventional case series with in vitro and ex vivo studies were performed. Vitrectomy was performed in 28 cases of epiretinal membrane with BBG single to multiple staining. The surgically resected membranes were stained by BBG with or without cellular fixation. Primary cell cultures were examined with BBG and live/death cell markers, such as Calcein AM and TUNEL. RESULTS: Single staining provided satisfactory staining in seven cases. Double or multiple staining substantially visualized internal limiting membrane (21 cases), especially the edges of remaining internal limiting membrane (11 cases). Adverse retinal staining was not noted and the final visual acuity showed no difference with multiple staining. The live cells barely stained with BBG, while some dead cells were stained. CONCLUSION: Brilliant Blue G multiple staining substantially enhanced the visualization of internal limiting membrane. The absence of abnormal staining supports the safety of repeated BBG staining.

Receptor interacting protein kinase mediates necrotic cone but not rod cell death in a mouse model of inherited degeneration.

Retinitis pigmentosa comprises a group of inherited retinal photoreceptor degenerations that lead to progressive loss of vision. Although in most cases rods, but not cones, harbor the deleterious gene mutations, cones do die in this disease, usually after the main phase of rod cell loss. Rod photoreceptor death is characterized by apoptotic features. In contrast, the mechanisms and features of subsequent nonautonomous cone cell death remain largely unknown. In this study, we show that receptor-interacting protein (RIP) kinase mediates necrotic cone cell death in rd10 mice, a mouse model of retinitis pigmentosa caused by a mutation in a rod-specific gene. The expression of RIP3, a key regulator of programmed necrosis, was elevated in rd10 mouse retinas in the phase of cone but not rod degeneration. Although rd10 mice lacking Rip3 developed comparable rod degeneration to control rd10 mice, they displayed a significant preservation of cone cells. Ultrastructural analysis of rd10 mouse retinas revealed that a substantial fraction of dying cones exhibited necrotic morphology, which was rescued by Rip3 deficiency. Additionally, pharmacologic treatment with a RIP kinase inhibitor attenuated histological and functional deficits of cones in rd10 mice. Thus, necrotic mechanisms involving RIP kinase are crucial in cone cell death in inherited retinal degeneration, suggesting the RIP kinase pathway as a potential target to protect cone-mediated central and peripheral vision loss in patients with retinitis pigementosa.