PURPOSE: The aim of this study was to develop a modified ex vivo corneal cross-linking method that increases stromal resistance to enzymatic degradation for use as a carrier for the Boston keratoprosthesis. METHODS: Ex vivo cross-linking of human corneas was performed using Barron artificial anterior chambers. The corneas were deepithelialized, pretreated with riboflavin solution (0.1% riboflavin/20% dextran), and irradiated with ultraviolet A (UV-A) light (λ = 370 nm, irradiance = 3 mW/cm) for various durations. The combined effect of UV-A and gamma (γ) irradiation was also assessed using the commercially available γ-irradiated corneal donors. The corneas were then trephined and incubated at 37°C with 0.3% collagenase A solution. The time to dissolution of each cornea was compared across treatments. RESULTS: Deepithelialized corneas (no UV light, no riboflavin) dissolved in 5.8 ± 0.6 hours. Cross-linked corneas demonstrated increased resistance to dissolution, with a time to dissolution of 17.8 ± 2.6 hours (P < 0.0001). The corneal tissues' resistance to collagenase increased with longer UV-A exposure, reaching a plateau at 30 minutes. Cross-linking both the anterior and posterior corneas did not provide added resistance when compared with cross-linking the anterior corneas only (P > 0.05). γ-irradiated corneas dissolved as readily as deepithelialized controls regardless of whether they were further cross-linked (5.6 ± 1.2 hours) or not (6.1 ± 0.6 hours) (P = 0.43). CONCLUSIONS: Collagen cross-linking of the deepithelialized anterior corneal surface for 30 minutes conferred optimal resistance to in vitro keratolysis by collagenase A.
PURPOSE: To investigate the levels of neutrophil elastase (NE), matrix metalloproteinases (MMPs), and myeloperoxidase (MPO) in tear washes of patients with ocular graft-vs-host disease (oGVHD). DESIGN: Case-control study. METHODS: Based on established criteria, oGVHD patients (n = 14; 28 eyes) and age-/sex-matched healthy controls (n = 14; 28 eyes) were enrolled. Tear washes were collected and analyzed for NE using a single-analyte enzyme-linked immunosorbent assay (ELISA). MMPs (1, 2, 3, 7, 8, 9, 12), MPO, and tissue inhibitor of matrix metalloproteinase (TIMP)-1 were analyzed using multianalyte bead-based ELISA assays. Total MMP activity was measured using a fluorimetric assay. Correlation studies were performed between NE, MMP-8, MMP-9, and MPO within study groups. RESULTS: NE, MMP-8, MMP-9, and MPO levels were elevated in oGVHD tears when compared with controls (P < .0001). NE was the most elevated analyte. MMP activity was higher and TIMP-1 levels were lower in oGVHD than in control (P < .0001). In oGVHD, NE significantly correlated with MMP-8 (r = 0.92), MMP-9 (r = 0.90), and MPO (r = 0.79) (P < .0001). MMP-8 correlated with MMP-9 (r = 0.96, P < .0001), and MPO (r = 0.60, P = .001). MMP-9 correlated with MPO (r = 0.55, P = .002). In controls, NE, MMP-9, and MPO significantly correlated with each other (P < .0001). CONCLUSIONS: The marked increase in NE in oGVHD tears that correlated strongly with elevated MMP-8, MMP-9, and MPO suggests a common neutrophilic source and provides evidence of neutrophil activity on the ocular surface of oGVHD patients.
Pericytes, the mural cells that constitute the capillaries along with endothelial cells, have been associated with the pathobiology of diabetic retinopathy; however, therapeutic implications of this association remain largely unexplored. Pericytes appear to be highly susceptible to the metabolic challenges associated with a diabetic environment, and there is substantial evidence that their loss may contribute to microvascular instability leading to the formation of microaneurysms, microhemorrhages, acellular capillaries, and capillary nonperfusion. Since pericytes are strategically located at the interface between the vascular and neural components of the retina, they offer extraordinary opportunities for therapeutic interventions in diabetic retinopathy. Moreover, the availability of novel imaging methodologies now allows for the in vivo visualization of pericytes, enabling a new generation of clinical trials that use pericyte tracking as clinical endpoints. The recognition of multiple signaling mechanisms involved in pericyte development and survival should allow for a renewed interest in pericytes as a therapeutic target for diabetic retinopathy.
PURPOSE: Pericytes, the vascular cells that constitute the outer layer of capillaries, have been shown to have a crucial role in vascular development and stability. Loss of pericytes precedes endothelial cell dysfunction and vascular degeneration in small-vessel diseases, including diabetic retinopathy. Despite their clinical relevance, the cellular pathways controlling survival of retinal pericytes remain largely uncharacterized. Therefore, we investigated the role of Notch signaling, a master regulator of cell fate decisions, in retinal pericyte survival. METHODS: A coculture system of ligand-dependent Notch signaling was developed using primary cultured retinal pericytes and a mesenchymal cell line derived from an inducible mouse model expressing the Delta-like 1 Notch ligand. This model was used to examine the effect of Notch activity on pericyte survival using quantitative PCR (qPCR) and a light-induced cell death assay. The effect of Notch gain- and loss-of-function was analyzed in monocultures of retinal pericytes using antibody arrays to interrogate the expression of apoptosis-related proteins. RESULTS: Primary cultured retinal pericytes differentially expressed key molecules of the Notch pathway and displayed strong expression of canonical Notch/RBPJK (recombination signal-binding protein 1 for J-kappa) downstream targets. A gene expression screen using gain- and loss-of-function approaches identified genes relevant to cell survival as downstream targets of Notch activity in retinal pericytes. Ligand-mediated Notch activity protected retinal pericytes from light-induced cell death. CONCLUSIONS: Our results have identified signature genes downstream of Notch activity in retinal pericytes and suggest that tight regulation of Notch signaling is crucial for pericyte survival.
Cell types are the basic building blocks of multicellular organisms and are extensively diversified in animals. Despite recent advances in characterizing cell types, classification schemes remain ambiguous. We propose an evolutionary definition of a cell type that allows cell types to be delineated and compared within and between species. Key to cell type identity are evolutionary changes in the 'core regulatory complex' (CoRC) of transcription factors, that make emergent sister cell types distinct, enable their independent evolution and regulate cell type-specific traits termed apomeres. We discuss the distinction between developmental and evolutionary lineages, and present a roadmap for future research.
Glycosylation is an important and common form of posttranscriptional modification of proteins in cells. During the last decade, a vast array of biological functions has been ascribed to glycans because of a rapid evolution in glycomic technologies. Glycogenes that are highly expressed at the human ocular surface include families of glycosyltransferases, proteoglycans, and glycan degradation proteins, as well as mucins and carbohydrate-binding proteins, such as the galectins. On the apical glycocalyx, mucin O-glycans promote boundary lubrication, prevent bacterial adhesion and endocytic activity, and maintain epithelial barrier function through interactions with galectins. The emerging roles attributed to glycans are contributing to the appreciation of their biological capabilities at the ocular surface.
The function of the meibomian gland in the upper and lower eyelids is critical to maintaining homeostasis at the ocular surface. Highly specialized meibocytes within the gland must differentiate and accumulate intracellular lipid droplets that are released into the tear film following rupture of the cell membrane. Proteases and their inhibitors have been recognized as key players in remodeling extracellular matrices and promoting the normal integrity of glandular tissue. They modulate a wide range of biological processes, such as cell proliferation and differentiation, and can contribute to disease when aberrantly expressed. Deciphering the role of proteolytic activity in the meibomian gland offers an opportunity to gain a more comprehensive and fundamental understanding of the developmental, physiological, and pathological processes associated with this gland.
PURPOSE: Mutation of RGR, encoding retinal G-protein coupled receptor was originally reported in association with retinal dystrophy in 1999. A single convincing recessive variant segregated perfectly in one family of five affected and two unaffected siblings. At least one further individual, homozygous for the same variant has since been reported. The aim of this report was to reevaluate the findings in consideration of data from a whole genome sequencing (WGS) study of a large cohort of retinal dystrophy families. METHODS: Whole genome sequencing was performed on 599 unrelated probands with inherited retinal disease. Detailed phenotyping was performed, including clinical evaluation, electroretinography, fundus photography, fundus autofluorescence imaging (FAF) and spectral-domain optical coherence tomography (OCT). RESULTS: Overall we confirmed that affected individuals from six unrelated families were homozygous for both the reported RGR p.Ser66Arg variant and a nearby frameshifting deletion in CDHR1 (p.Ile841Serfs119*). All had generalized rod and cone dysfunction with severe macular involvement. An additional proband was heterozygous for the same CDHR1/RGR haplotype but also carried a second null CDHR1 mutation on a different haplotype. A comparison of the clinical presentation of the probands reported here with other CDHR1-related retinopathy patients shows the phenotypes to be similar in presentation, severity, and rod/cone involvement. CONCLUSIONS: These data suggest that the recessive retinal disorder previously reported to be due to homozygous mutation in RGR is, at least in part, due to variants in CDHR1 and that the true consequences of RGR knock-out on human retinal structure and function are yet to be determined.
PURPOSE: To report a case of successful medical treatment with oral posaconazole in refractory fungal keratitis caused by Paecilomyces lilacinus. METHODS: Case report. RESULTS: A 57-year-old male, soft contact lens wearer presented with irritation, pain, photophobia, and reduced vision. Slit-lamp examination showed a large corneal epithelial defect with a peripheral infiltrate. The patient did not improve on fortified topical antibiotics. After the diagnosis of P. lilacinus fungal keratitis, oral voriconazole and topical antifungal therapy were started. Despite antifungal therapy, progressive disease required therapeutic penetrating keratoplasty. Postoperatively, because of clinical signs of recurrence and in vivo confocal microscopy findings of presumed hyphae in the cornea, intracameral miconazole was injected and oral posaconazole was started. The patient improved and demonstrated no hyphae 6 weeks after starting posaconazole. When posaconazole was stopped, the cornea remained clear with excellent acuity. However, because of acute graft rejection 2 months after stopping posaconazole, keratoprosthesis was implanted, with no evidence of infection at surgery or during the 3.5-year follow-up. CONCLUSIONS: To the best of our knowledge, this is the first report on the use of oral posaconazole for Paecilomyces keratitis. Posaconazole might be indicated in the treatment of refractory Paecilomyces keratitis that is resistant to conventional therapy.
PURPOSE: To identify factors predictive of remission of inflammation in new-onset anterior uveitis cases treated at tertiary uveitis care facilities.
DESIGN: Retrospective cohort study.
PARTICIPANTS: Patients seeking treatment at participating academic uveitis clinics within 90 days of initial diagnosis of anterior uveitis.
METHODS: Retrospective cohort study based on standardized chart review.
MAIN OUTCOME MEASURES: Factors predictive of remission (no disease activity without corticosteroid or immunosuppressive treatments at all visits during a 90-day period).
RESULTS: Nine hundred ninety eyes (687 patients) had a first-ever diagnosis of anterior uveitis within 90 days before initial presentation and had follow-up visits thereafter. The median follow-up time was 160 days. Systemic diagnoses with juvenile idiopathic arthritis (JIA; adjusted hazard ratio [aHR], 0.38; 95% confidence interval [CI], 0.19-0.74) and Behçet's disease (aHR, 0.10; 95% CI, 0.01-0.85) were associated with a lower incidence of uveitis remission. Cases of bilateral uveitis (aHR, 0.68; 95% CI, 0.54-0.87) and those with a history of cataract surgery before presentation (aHR, 0.51; 95% CI, 0.29-0.87) also had a lower incidence of remission. Regarding clinical findings at the initial visit, a high degree of vitreous cells at initial presentation was associated with a lower incidence of remission (for 1+ or more vs. none: aHR, 0.72; 95% CI, 0.55-0.95). An initial visual acuity of 20/200 or worse, with respect to 20/40 or better, also was predictive of a lower incidence of remission (aHR, 0.52; 95% CI, 0.32-0.86).
CONCLUSIONS: Factors associated with a lower incidence of remission among new-onset anterior uveitis cases included diagnosis with JIA, Behçet's disease, bilateral uveitis, history of cataract surgery, findings of 1+ or more vitreous cells at presentation, and an initial visual acuity of 20/200 or worse. Patients with these risk factors seem to be at higher risk of persistent inflammation; reciprocally, patients lacking these factors would be more likely to experience remission. Patients with risk factors for nonremission of uveitis should be managed taking into account the higher probability of a chronic inflammatory course.
Aschard H, Kang JH, Iglesias AI, Hysi P, Cooke Bailey JN, Khawaja AP, Allingham RR, Ashley-Koch A, Lee RK, Moroi SE, Brilliant MH, Wollstein G, Schuman JS, Fingert JH, Budenz DL, Realini T, Gaasterland T, Scott WK, Singh K, Sit AJ, Igo RP, Song YE, Hark L, Ritch R, Rhee DJ, Gulati V, Haven S, Vollrath D, Zack DJ, Medeiros F, Weinreb RN, Cheng C-Y, Chasman DI, Christen WG, Pericak-Vance MA, Liu Y, Kraft P, Richards JE, Rosner BA, Hauser MA, Hauser MA, Klaver CCW, van Duijn CM, Haines J, Wiggs JL, Pasquale LR. Genetic correlations between intraocular pressure, blood pressure and primary open-angle glaucoma: a multi-cohort analysis. Eur J Hum Genet 2017;25(11):1261-1267.Abstract
Primary open-angle glaucoma (POAG) is the most common chronic optic neuropathy worldwide. Epidemiological studies show a robust positive relation between intraocular pressure (IOP) and POAG and modest positive association between IOP and blood pressure (BP), while the relation between BP and POAG is controversial. The International Glaucoma Genetics Consortium (n=27 558), the International Consortium on Blood Pressure (n=69 395), and the National Eye Institute Glaucoma Human Genetics Collaboration Heritable Overall Operational Database (n=37 333), represent genome-wide data sets for IOP, BP traits and POAG, respectively. We formed genome-wide significant variant panels for IOP and diastolic BP and found a strong relation with POAG (odds ratio and 95% confidence interval: 1.18 (1.14-1.21), P=1.8 × 10-27) for the former trait but no association for the latter (P=0.93). Next, we used linkage disequilibrium (LD) score regression, to provide genome-wide estimates of correlation between traits without the need for additional phenotyping. We also compared our genome-wide estimate of heritability between IOP and BP to an estimate based solely on direct measures of these traits in the Erasmus Rucphen Family (ERF; n=2519) study using Sequential Oligogenic Linkage Analysis Routines (SOLAR). LD score regression revealed high genetic correlation between IOP and POAG (48.5%, P=2.1 × 10-5); however, genetic correlation between IOP and diastolic BP (P=0.86) and between diastolic BP and POAG (P=0.42) were negligible. Using SOLAR in the ERF study, we confirmed the minimal heritability between IOP and diastolic BP (P=0.63). Overall, IOP shares genetic basis with POAG, whereas BP has limited shared genetic correlation with IOP or POAG.
Long intervening non-coding RNAs (lincRNAs) are increasingly being implicated as important factors in many aspects of cellular development, function, and disease, but remain poorly understood. In this study, we examine the human retinal pigment epithelium (RPE) lincRNA transcriptome using RNA-Seq data generated from human fetal RPE (fRPE), RPE derived from human induced pluripotent stem cells (iPS-RPE), and undifferentiated iPS (iPS). In addition, we determine the suitability of iPS-RPE, from a transcriptome standpoint, as a model for use in future studies of lincRNA structure and function. A comparison of gene and isoform expression across the whole transcriptome shows only minimal differences between all sample types, though fRPE and iPS-RPE show higher concordance than either shows with iPS. Notably, RPE signature genes show the highest degree of fRPE to iPS-RPE concordance, indicating that iPS-RPE cells provide a suitable model for use in future studies. An analysis of lincRNAs demonstrates high concordance between fRPE and iPS-RPE, but low concordance between either RPE and iPS. While most lincRNAs are expressed at low levels (RPKM < 10), there is a high degree of concordance among replicates within each sample type, suggesting the expression is consistent, even at levels subject to high variability. Finally, we identified and annotated 180 putative novel genes in the fRPE samples, a majority of which are also expressed in the iPS-RPE. Overall, this study represents the first characterization of lincRNA expression in the human RPE, and provides a model for studying the role lincRNAs play in RPE development, function, and disease.
Aung T, Ozaki M, Lee MC, Schlötzer-Schrehardt U, Thorleifsson G, Mizoguchi T, Igo RP, Haripriya A, Williams SE, Astakhov YS, Orr AC, Burdon KP, Nakano S, Mori K, Abu-Amero K, Hauser M, Li Z, Prakadeeswari G, Bailey JCN, Cherecheanu AP, Kang JH, Nelson S, Hayashi K, Manabe S-I, Kazama S, Zarnowski T, Inoue K, Irkec M, Coca-Prados M, Sugiyama K, Järvelä I, Schlottmann P, Lerner FS, Lamari H, Nilgün Y, Bikbov M, Park KH, Cha SC, Yamashiro K, Zenteno JC, Jonas JB, Kumar RS, Perera SA, Chan ASY, Kobakhidze N, George R, Vijaya L, Do T, Edward DP, de Juan Marcos L, Pakravan M, Moghimi S, Ideta R, Bach-Holm D, Kappelgaard P, Wirostko B, Thomas S, Gaston D, Bedard K, Greer WL, Yang Z, Chen X, Huang L, Sang J, Jia H, Jia L, Qiao C, Zhang H, Liu X, Zhao B, Wang Y-X, Xu L, Leruez S, Reynier P, Chichua G, Tabagari S, Uebe S, Zenkel M, Berner D, Mossböck G, Weisschuh N, Hoja U, Welge-Luessen U-C, Mardin C, Founti P, Chatzikyriakidou A, Pappas T, Anastasopoulos E, Lambropoulos A, Ghosh A, Shetty R, Porporato N, Saravanan V, Venkatesh R, Shivkumar C, Kalpana N, Sarangapani S, Kanavi MR, Beni AN, Yazdani S, Lashay A, Naderifar H, Khatibi N, Fea A, Lavia C, Dallorto L, Rolle T, Frezzotti P, Paoli D, Salvi E, Manunta P, Mori Y, Miyata K, Higashide T, Chihara E, Ishiko S, Yoshida A, Yanagi M, Kiuchi Y, Ohashi T, Sakurai T, Sugimoto T, Chuman H, Aihara M, Inatani M, Miyake M, Gotoh N, Matsuda F, Yoshimura N, Ikeda Y, Ueno M, Sotozono C, Jeoung JW, Sagong M, Park KH, Ahn J, Cruz-Aguilar M, Ezzouhairi SM, Rafei A, Chong YF, Ng XY, Goh SR, Chen Y, Yong VHK, Khan MI, Olawoye OO, Ashaye AO, Ugbede I, Onakoya A, Kizor-Akaraiwe N, Teekhasaenee C, Suwan Y, Supakontanasan W, Okeke S, Uche NJ, Asimadu I, Ayub H, Akhtar F, Kosior-Jarecka E, Lukasik U, Lischinsky I, Castro V, Grossmann RP, Megevand GS, Roy S, Dervan E, Silke E, Rao A, Sahay P, Fornero P, Cuello O, Sivori D, Zompa T, Mills RA, Souzeau E, Mitchell P, Wang JJ, Hewitt AW, Coote M, Crowston JG, Astakhov SY, Akopov EL, Emelyanov A, Vysochinskaya V, Kazakbaeva G, Fayzrakhmanov R, Al-Obeidan SA, Owaidhah O, Aljasim LA, Chowbay B, Foo JN, Soh RQ, Sim KS, Xie Z, Cheong AWO, Mok SQ, Soo HM, Chen XY, Peh SQ, Heng KK, Husain R, Ho S-L, Hillmer AM, Cheng C-Y, Escudero-Domínguez FA, González-Sarmiento R, Martinon-Torres F, Salas A, Pathanapitoon K, Hansapinyo L, Wanichwecharugruang B, Kitnarong N, Sakuntabhai A, Nguyn HX, Nguyn GTT, Nguyn TV, Zenz W, Binder A, Klobassa DS, Hibberd ML, Davila S, Herms S, Nöthen MM, Moebus S, Rautenbach RM, Ziskind A, Carmichael TR, Ramsay M, Álvarez L, García M, González-Iglesias H, Rodríguez-Calvo PP, Cueto LF-V, Oguz Ç, Tamcelik N, Atalay E, Batu B, Aktas D, Kasım B, Wilson RM, Coleman AL, Liu Y, Challa P, Herndon L, Kuchtey RW, Kuchtey J, Curtin K, Chaya CJ, Crandall A, Zangwill LM, Wong TY, Nakano M, Kinoshita S, den Hollander AI, Vesti E, Fingert JH, Lee RK, Sit AJ, Shingleton BJ, Wang N, Cusi D, Qamar R, Kraft P, Pericak-Vance MA, Raychaudhuri S, Heegaard S, Kivelä T, Reis A, Kruse FE, Weinreb RN, Pasquale LR, Haines JL, Thorsteinsdottir U, Jonasson F, Allingham RR, Milea D, Ritch R, Kubota T, Tashiro K, Vithana EN, Micheal S, Topouzis F, Craig JE, Dubina M, Sundaresan P, Stefansson K, Wiggs JL, Pasutto F, Khor CC. Genetic association study of exfoliation syndrome identifies a protective rare variant at LOXL1 and five new susceptibility loci. Nat Genet 2017;Abstract
Exfoliation syndrome (XFS) is the most common known risk factor for secondary glaucoma and a major cause of blindness worldwide. Variants in two genes, LOXL1 and CACNA1A, have previously been associated with XFS. To further elucidate the genetic basis of XFS, we collected a global sample of XFS cases to refine the association at LOXL1, which previously showed inconsistent results across populations, and to identify new variants associated with XFS. We identified a rare protective allele at LOXL1 (p.Phe407, odds ratio (OR) = 25, P = 2.9 × 10(-14)) through deep resequencing of XFS cases and controls from nine countries. A genome-wide association study (GWAS) of XFS cases and controls from 24 countries followed by replication in 18 countries identified seven genome-wide significant loci (P < 5 × 10(-8)). We identified association signals at 13q12 (POMP), 11q23.3 (TMEM136), 6p21 (AGPAT1), 3p24 (RBMS3) and 5q23 (near SEMA6A). These findings provide biological insights into the pathology of XFS and highlight a potential role for naturally occurring rare LOXL1 variants in disease biology.
Aung T, Ozaki M, Mizoguchi T, Allingham RR, Li Z, Haripriya A, Nakano S, Uebe S, Harder JM, Chan ASY, Lee MC, Burdon KP, Astakhov YS, Abu-Amero KK, Zenteno JC, Nilgün Y, Zarnowski T, Pakravan M, Safieh LA, Jia L, Wang YX, Williams S, Paoli D, Schlottmann PG, Huang L, Sim KS, Foo JN, Nakano M, Ikeda Y, Kumar RS, Ueno M, Manabe S-I, Hayashi K, Kazama S, Ideta R, Mori Y, Miyata K, Sugiyama K, Higashide T, Chihara E, Inoue K, Ishiko S, Yoshida A, Yanagi M, Kiuchi Y, Aihara M, Ohashi T, Sakurai T, Sugimoto T, Chuman H, Matsuda F, Yamashiro K, Gotoh N, Miyake M, Astakhov SY, Osman EA, Al-Obeidan SA, Owaidhah O, Al-Jasim L, Shahwan SA, Fogarty RA, Leo P, Yetkin Y, Oğuz Ç, Kanavi MR, Beni AN, Yazdani S, Akopov EL, Toh K-Y, Howell GR, Orr AC, Goh Y, Meah WY, Peh SQ, Kosior-Jarecka E, Lukasik U, Krumbiegel M, Vithana EN, Wong TY, Liu Y, Koch AAE, Challa P, Rautenbach RM, Mackey DA, Hewitt AW, Mitchell P, Wang JJ, Ziskind A, Carmichael T, Ramakrishnan R, Narendran K, Venkatesh R, Vijayan S, Zhao P, Chen X, Guadarrama-Vallejo D, Cheng CY, Perera SA, Husain R, Ho S-L, Welge-Luessen U-C, Mardin C, Schloetzer-Schrehardt U, Hillmer AM, Herms S, Moebus S, Nöthen MM, Weisschuh N, Shetty R, Ghosh A, Teo YY, Brown MA, Lischinsky I, Lischinsky I, Lischinsky I, Crowston JG, Coote M, Zhao B, Sang J, Zhang N, You Q, Vysochinskaya V, Founti P, Chatzikyriakidou A, Lambropoulos A, Anastasopoulos E, Coleman AL, Wilson RM, Rhee DJ, Kang JH, May-Bolchakova I, Heegaard S, Mori K, Alward WLM, Jonas JB, Xu L, Liebmann JM, Chowbay B, Schaeffeler E, Schwab M, Lerner F, Wang N, Yang Z, Frezzotti P, Kinoshita S, Fingert JH, Inatani M, Tashiro K, Reis A, Edward DP, Pasquale LR, Kubota T, Wiggs JL, Pasutto F, Topouzis F, Dubina M, Craig JE, Yoshimura N, Sundaresan P, John SWM, Ritch R, Hauser MA, Khor C-C. A common variant mapping to CACNA1A is associated with susceptibility to exfoliation syndrome. Nat Genet 2015;47(4):387-92.Abstract
Exfoliation syndrome (XFS) is the most common recognizable cause of open-angle glaucoma worldwide. To better understand the etiology of XFS, we conducted a genome-wide association study (GWAS) of 1,484 cases and 1,188 controls from Japan and followed up the most significant findings in a further 6,901 cases and 20,727 controls from 17 countries across 6 continents. We discovered a genome-wide significant association between a new locus (CACNA1A rs4926244) and increased susceptibility to XFS (odds ratio (OR) = 1.16, P = 3.36 × 10(-11)). Although we also confirmed overwhelming association at the LOXL1 locus, the key SNP marker (LOXL1 rs4886776) demonstrated allelic reversal depending on the ancestry group (Japanese: ORA allele = 9.87, P = 2.13 × 10(-217); non-Japanese: ORA allele = 0.49, P = 2.35 × 10(-31)). Our findings represent the first genetic locus outside of LOXL1 surpassing genome-wide significance for XFS and provide insight into the biology and pathogenesis of the disease.
Purpose: Intraocular medulloepithelioma (IM), the second most common primary neuroepithelial tumor of the eye, can lead to blindness in the affected eye and in rare cases, is deadly. Intraocular medulloepithelioma lacks targetable biomarkers for potential pharmacologic therapy. The purpose of this study was to identify actionable, tumor-specific proteins for potential diagnostic or therapeutic strategies. We hypothesize that the tumor-specific epigenetic enzyme EZH2 is selectively expressed in IM. Methods: We conducted a retrospective case series study of five IM from five eyes of four children and one adult. Hematoxylin and eosin (H&E) stains of sections from formalin-fixed, paraffin-embedded blocks of IM tumors were used to localize IM tumor cells in each case. Using an EZH2-specific antibody for immunohistochemistry, we semiquantitatively calculated the proportion of IM tumor cells positive for EZH2, and also assayed for EZH2 staining intensity. Results: We found that EZH2 was expressed in all IM cases but this protein was absent in nontumor ciliary body or retinal tissues. However, not all IM tumor cells expressed EZH2. Similar to retinoblastoma, moderately to poorly differentiated (primitive appearing) IM tumor cells strongly expressed EZH2; expression was weaker or absent in areas of well-formed neuroepithelial units. Conclusions: To our knowledge, this is the first study to identify an actionable tumor-specific maker, EZH2, in IM. Our findings point to the possibility of exploring the potential of EZH2 inhibitors, already in clinical trials for other cancers, for IM.
TOPIC: Children and adults with neurofibromatosis type 1 (NF1), a common autosomal dominant condition, manifest a variety of ophthalmologic conditions. Plexiform neurofibromas (PNs) involving the eyelid, orbit, periorbital, and facial structures (orbital-periorbital plexiform neurofibroma [OPPN]) can result in significant visual loss in children. Equally important, OPPNs can cause significant alteration in physical appearance secondary to proptosis, ptosis, and facial disfigurement, leading to social embarrassment and decreased self-esteem. CLINICAL RELEVANCE: Although NF1 is a relatively common disease in which routine ophthalmologic examinations are required, no formal recommendations for clinical care of children with OPPNs exist. Although medical and surgical interventions have been reported, there are no agreed-on criteria for when OPPNs require therapy and which treatment produces the best outcome. METHODS: Because a multidisciplinary team of specialists (oculofacial plastics, pediatric ophthalmology, neuro-ophthalmology, medical genetics, and neuro-oncology) direct management decisions, the absence of a uniform outcome measure that represents visual or aesthetic sequelae complicates the design of evidence-based studies and feasible clinical trials. RESULTS: In September 2013, a multidisciplinary task force, composed of pediatric practitioners from tertiary care centers experienced in caring for children with OPPN, was convened to address the lack of clinical care guidelines for children with OPPN. CONCLUSIONS: This consensus statement provides recommendations for ophthalmologic monitoring, outlines treatment indications and forthcoming biologic therapy, and discusses challenges to performing clinical trials in this complicated condition.
Purpose: We describe the clinical features in two pedigrees with dominantly inherited retinopathy segregating the previously reported frameshifting mutation, c.836dupG (p.Ile280Asn*78) in the terminal exon of the RGR gene, and compare their haplotypes to that of the previously reported pedigree. Methods: The probands were ascertained at West Virginia University Eye Institute (WVU) and Moorfields Eye Hospital (MEH) through next generation sequencing (NGS) and whole genome sequencing (WGS) respectively. Clinical data included visual acuity (VA), visual fields, fundus autofluorescence (FAF), optical coherence tomography (OCT), and electroretinography (ERG). Haplotype analysis was performed using Sanger sequencing of the DNA from the molecularly ascertained individuals from the three pedigrees. Results: Nine heterozygous mutation carriers were identified in two families. Four carriers were asymptomatic; five carriers had variable VA reduction, visual field constriction, and experienced difficulty under dim illumination. Fundus examination of the asymptomatic carriers showed diffuse or reticular pigmentation of the retina; the symptomatic carriers had chorioretinal atrophy. FAF imaging showed widespread signal loss in advanced retinopathy, and reticular hyperautofluorescence in mild cases. OCT showed loss of outer retinal lamina in advanced disease. ERG showed moderate-to-severe rod-cone dysfunction in two symptomatic carriers; and was normal in three asymptomatic carriers. A shared haplotype flanking the mutation of up to 6.67 Mb was identified in both families. Within this region, 1.27 Mb were shared with the first family reported with this retinopathy. Conclusions: The clinical data suggest a variable and slow degeneration of the RPE. A shared chromosomal segment surrounding the RGR gene suggests a single ancestral mutational event underlying all three families.
PURPOSE: To report the phenotypic and genotypic data of a patient with retinitis punctata albescens carrying a novel deletion in the RLBP1 gene. RESULTS: A woman of Iranian descent in her forties with a history of progressive visual deterioration since early childhood exhibited phenotypic features of retinitis punctata albescens with multiple white dots in the posterior pole and macular atrophy in both eyes. The microarray analysis identified a ∼2.160 kb homozygous deletion corresponding to a minimum deletion boundary of chr15q26.1:89,756,882-89,759,041/GRCh37 (hg19), which encompasses exon 6 of the RLBP1 gene. CONCLUSION: We describe a novel large homozygous deletion in the RLBP1 gene encoding the cellular retinaldehyde-binding protein in a patient of Iranian descent with retinitis punctata albescens. Genotype-phenotype studies may provide more information about the functions of the RLBP1 encoding proteins and the disease course, because RLBP1 mutations are associated with high phenotypic variability and are therefore a necessity for future tailored individual therapies.
Bailey JCN, Gharahkhani P, Kang JH, Butkiewicz M, Sullivan DA, Weinreb RN, Aschard H, Allingham RR, Ashley-Koch A, Lee RK, Moroi SE, Brilliant MH, Wollstein G, Schuman JS, Fingert JH, Budenz DL, Realini T, Gaasterland T, Scott WK, Singh K, Sit AJ, Igo RP, Song YE, Hark L, Ritch R, Rhee DJ, Vollrath D, Zack DJ, Medeiros F, Vajaranant TS, Chasman DI, Christen WG, Pericak-Vance MA, Liu Y, Kraft P, Richards JE, Rosner BA, Hauser MA, Craig JE, Burdon KP, Hewitt AW, Mackey DA, Haines JL, Macgregor S, Wiggs JL, Pasquale LR, and of Consortium ANZRAG (ANZRAG). Testosterone Pathway Genetic Polymorphisms in Relation to Primary Open-Angle Glaucoma: An Analysis in Two Large Datasets. Invest Ophthalmol Vis Sci 2018;59(2):629-636.Abstract
Purpose: Sex hormones may be associated with primary open-angle glaucoma (POAG), although the mechanisms are unclear. We previously observed that gene variants involved with estrogen metabolism were collectively associated with POAG in women but not men; here we assessed gene variants related to testosterone metabolism collectively and POAG risk. Methods: We used two datasets: one from the United States (3853 cases and 33,480 controls) and another from Australia (1155 cases and 1992 controls). Both datasets contained densely called genotypes imputed to the 1000 Genomes reference panel. We used pathway- and gene-based approaches with Pathway Analysis by Randomization Incorporating Structure (PARIS) software to assess the overall association between a panel of single nucleotide polymorphisms (SNPs) in testosterone metabolism genes and POAG. In sex-stratified analyses, we evaluated POAG overall and POAG subtypes defined by maximum IOP (high-tension [HTG] or normal tension glaucoma [NTG]). Results: In the US dataset, the SNP panel was not associated with POAG (permuted P = 0.77), although there was an association in the Australian sample (permuted P = 0.018). In both datasets, the SNP panel was associated with POAG in men (permuted P ≤ 0.033) and not women (permuted P ≥ 0.42), but in gene-based analyses, there was no consistency on the main genes responsible for these findings. In both datasets, the testosterone pathway association with HTG was significant (permuted P ≤ 0.011), but again, gene-based analyses showed no consistent driver gene associations. Conclusions: Collectively, testosterone metabolism pathway SNPs were consistently associated with the high-tension subtype of POAG in two datasets.