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1.
Curr Opin Pharmacol ; 48: 114-119, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31590110

RESUMO

Human pluripotent stem cells can be differentiated into specific, relevant cell types of interest including the cells of the retina and optic nerve. These cells can then be used to study fundamental biology as well as disease modelling and subsequent screening of potential treatments. Many models of differentiation and modelling have relied on two-dimensional monocultures of specific cell types, which are not representative of the complexity of the human retina and optic nerve. Hence, more complex models of the human retina and optic nerve are required. Three-dimensional organoids and emerging cell culture methods may provide more physiologically relevant models to study developmental biology and pathology of the retina and optic nerve.

2.
Stem Cell Reports ; 13(4): 669-683, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31522977

RESUMO

Here we elucidate the effect of Alzheimer disease (AD)-predisposing genetic backgrounds, APOE4, PSEN1ΔE9, and APPswe, on functionality of human microglia-like cells (iMGLs). We present a physiologically relevant high-yield protocol for producing iMGLs from induced pluripotent stem cells. Differentiation is directed with small molecules through primitive erythromyeloid progenitors to re-create microglial ontogeny from yolk sac. The iMGLs express microglial signature genes and respond to ADP with intracellular Ca2+ release distinguishing them from macrophages. Using 16 iPSC lines from healthy donors, AD patients and isogenic controls, we reveal that the APOE4 genotype has a profound impact on several aspects of microglial functionality, whereas PSEN1ΔE9 and APPswe mutations trigger minor alterations. The APOE4 genotype impairs phagocytosis, migration, and metabolic activity of iMGLs but exacerbates their cytokine secretion. This indicates that APOE4 iMGLs are fundamentally unable to mount normal microglial functionality in AD.

3.
Invest Ophthalmol Vis Sci ; 60(12): 3937-3942, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31546259

RESUMO

Purpose: Few studies have explored the association of genetic variants in microRNA genes and binding sites with diabetic retinopathy (DR) in type 1 diabetes. We conducted a genome-wide scan for single nucleotide polymorphisms (SNPs) in these genes by using data from a genome-wide association study (GWAS). Methods: All known SNPs were imputed from our GWAS data (n = 325) of DR cases and diabetic controls (no DR). Relevant SNPS were extracted using miRNASNP and PolymiRTS (version 2) databases. χ2 tests and logistic regression (adjusting for age, sex, duration of diabetes, HbA1c, and hypertension) were used to test the association between the imputed SNPs and DR phenotypes (any DR, nonproliferative DR [NPDR], proliferative DR [PDR], diabetic macular edema [DME], and sight-threatening DR defined as PDR, severe NPDR, or clinically significant macula edema [CSME]) compared with diabetic controls. Top-ranking SNPs were genotyped in a larger cohort (N = 560) to confirm their association with DR. Results: Three SNPs (rs10061133, rs1049835, rs9501255) were selected and genotyped in the final cohort. Rs10061133 in MIR449b was protective of sight-threatening DR (odds ratio [OR] = 0.32, P = 3.68 × 10-4) and PDR (OR = 0.30, P = 8.12 × 10-4), and the associations became more significant as the cohort increased in size. Conclusions: Rs10061133 in MIR449b is significantly associated with a decreased risk of PDR and sight-threatening DR in Caucasian patients with type 1 diabetes. This can guide future studies on genetic risk profiling and on developing microRNA-related therapies for sight-threatening DR.

4.
Surv Ophthalmol ; 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31541618

RESUMO

Smartphones are an increasingly common and rapidly developing tool in clinical practice. Numerous applications or 'apps' are available for use on smartphones that aim to help clinicians perform a variety of tasks at the point of care. A large number of ophthalmology-related medical apps that can perform a variety of clinically relevant functions are now available in virtual stores such as the Google Play™ Store or the Apple App Store®. On the ophthalmic front, these include measures of visual acuity, tools to assist in the assessment and treatment of conditions such as amblyopia and glaucoma, as well as add-on devices that allow visualization and photography of the anterior and posterior segments of the eye. Despite the large number of available programs, the evidence supporting their use is unclear, with issues concerning professional input in development, regulation, validation and security of information. We present the various uses of smartphones in ophthalmology and summarize the current literature.

5.
EMBO J ; 38(18): e100811, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31436334

RESUMO

The retina is a specialized neural tissue that senses light and initiates image processing. Although the functional organization of specific retina cells has been well studied, the molecular profile of many cell types remains unclear in humans. To comprehensively profile the human retina, we performed single-cell RNA sequencing on 20,009 cells from three donors and compiled a reference transcriptome atlas. Using unsupervised clustering analysis, we identified 18 transcriptionally distinct cell populations representing all known neural retinal cells: rod photoreceptors, cone photoreceptors, Müller glia, bipolar cells, amacrine cells, retinal ganglion cells, horizontal cells, astrocytes, and microglia. Our data captured molecular profiles for healthy and putative early degenerating rod photoreceptors, and revealed the loss of MALAT1 expression with longer post-mortem time, which potentially suggested a novel role of MALAT1 in rod photoreceptor degeneration. We have demonstrated the use of this retina transcriptome atlas to benchmark pluripotent stem cell-derived cone photoreceptors and an adult Müller glia cell line. This work provides an important reference with unprecedented insights into the transcriptional landscape of human retinal cells, which is fundamental to understanding retinal biology and disease.

7.
Hum Gene Ther ; 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31373227

RESUMO

Safe delivery of CRISPR/Cas endonucleases remains one of the major barriers to the widespread application of in vivo genome editing. We previously reported the utility of adeno-associated virus (AAV)-mediated CRISPR/Cas genome editing in the retina; however, with this type of viral delivery system, active endonucleases will remain in the retina for an extended period, making genotoxicity a significant consideration in clinical applications. To address this issue, we have designed a self-destructing "kamikaze" CRISPR/Cas system that disrupts the Cas enzyme itself following expression. Four guide RNAs (sgRNAs) were initially designed to target Streptococcus pyogenes Cas9 (SpCas9) and after in situ validation, the selected sgRNAs were cloned into a dual AAV vector. One construct was used to deliver SpCas9 and the other delivered sgRNAs directed against SpCas9 and the target locus (yellow fluorescent protein, YFP), in the presence of mCherry. Both constructs were packaged into AAV2 vectors and intravitreally administered in C57BL/6 and Thy1-YFP transgenic mice. After 8 weeks the expression of SpCas9 and the efficacy of YFP gene disruption was quantified. A reduction of SpCas9 mRNA was found in retinas treated with AAV2-mediated-YFP/SpCas9 targeting CRISPR/Cas compared to those treated with YFP targeting CRISPR/Cas alone. We also show that AAV2-mediated delivery of YFP/SpCas9 targeting CRISPR/Cas significantly reduced the number of YFP fluorescent cells among mCherry-expressing cells (~85.5% reduction compared to LacZ/SpCas9 targeting CRISPR/Cas) in the transfected retina of Thy1-YFP transgenic mice. In conclusion, our data suggest that a self-destructive "kamikaze" CRISPR/Cas system can be used as a robust tool for genome editing in the retina, without compromising on-target efficiency.

8.
Ophthalmology ; 126(10): 1372-1384, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31196726

RESUMO

PURPOSE: Obstructive sleep apnea (OSA) is linked to increased glaucoma risk in middle-aged and older adults. However, little is known about associations between OSA and glaucoma-related optic disc parameters in young adults. We explored associations between overnight polysomnography-derived measures of OSA and the optic disc in young adults. DESIGN: Cross-sectional cohort study. PARTICIPANTS: Eight hundred forty-eight adults 19 to 22 years of age. METHODS: Participants underwent an ophthalmic examination that included OCT imaging of the optic disc and measurements of intraocular pressure, axial length, and refractive error. Participants then underwent an overnight polysomnography study that obtained measurements of apnea-hypopnea index (AHI), peripheral oxygen saturation level, and number of cortical arousals from sleep. Based on the AHI results, participants were grouped into no OSA (AHI < 5 events/hour), mild OSA (AHI ≥ 5 and <15 events/hour), moderate OSA (AHI ≥ 15 and <30 events/hour), or severe OSA (AHI ≥ 30 events/hour). MAIN OUTCOME MEASURES: Neuroretinal rim area, horizontal and vertical widths, and peripapillary retinal nerve fiber layer (RNFL) thickness. RESULTS: The median AHI result across the study cohort was 2.2 events per hour (interquartile range, 1.0-4.4 events/hour). Based on the AHI results, 178 participants (21.0%) demonstrated OSA: 150 with mild OSA, 26 with moderate OSA, and 2 with severe OSA. In the unadjusted analyses, participants with OSA on average showed thinner peripapillary RNFL at the inferotemporal (P = 0.026) and superotemporal (P = 0.008) segments compared with those without OSA. Additionally, higher AHI results were associated with thinner RNFL superotemporally (P = 0.007). These findings remained significant after adjusting for gender, body mass index, ethnicity, and potential ocular confounders. There were no significant differences in optic disc measures between groups of OSA severity. CONCLUSIONS: Obstructive sleep apnea may be associated with preclinical thinning of the peripapillary RNFL in young adults. This suggests that an increased glaucoma risk already may be present in individuals with OSA since young adulthood. Long-term follow-up of this cohort will allow further optic disc changes in relationship to polysomnography parameters to be documented and associations with future glaucoma diagnosis to be explored.

11.
Am J Ophthalmol ; 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31121135

RESUMO

PURPOSE: A genetic correlation is the proportion of phenotypic variance between traits that is shared on a genetic basis. Here we explore genetic correlations between diabetes- and glaucoma-related traits. DESIGN: Cross-sectional study. METHODS: We assembled genome-wide association study summary statistics from European-derived participants regarding diabetes-related traits like fasting blood sugar (FBS) and type 2 diabetes (T2D) and glaucoma-related traits (intraocular pressure (IOP), central corneal thickness (CCT), corneal hysteresis (CH), corneal resistance factor (CRF), cup-disc ratio (CDR), and primary open-angle glaucoma (POAG)). We included data from the National Eye Institute Glaucoma Human Genetics Collaboration Heritable Overall Operational Database, the UK Biobank and the International Glaucoma Genetics Consortium. We calculated genetic correlation (rg) between traits using linkage disequilibrium score regression. We also calculated genetic correlations between IOP, CCT and selected diabetes-related traits based on individual level phenotype data in two Northern European population-based samples using pedigree information and Sequential Oligogenic Linkage Analysis Routines (SOLAR). RESULTS: Overall, there was little rg between diabetes- and glaucoma-related traits. Specifically, we found a non-significant negative correlation between T2D and POAG (rg=-0.14; p=0.16). Using SOLAR, the genetic correlations between measured IOP, CCT, FBS, fasting insulin and hemoglobin A1c, were null. In contrast, genetic correlations between IOP and POAG (rg ≥0.45; p≤3.0E-04) and between CDR and POAG were high (rg =0.57; p=2.8E-10). However, genetic correlations between corneal properties (CCT, CRF and CH) and POAG were low (rg range: -0.18 - 0.11) and non-significant (p≥0.07). CONCLUSION: These analyses suggest there is limited genetic correlation between diabetes- and glaucoma-related traits.

12.
Front Cell Neurosci ; 13: 147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130844

RESUMO

[This corrects the article DOI: 10.3389/fncel.2018.00460.].

13.
Mol Vis ; 25: 174-182, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30996586

RESUMO

Purpose: To evaluate the efficacy of using a CRISPR/Cas-mediated strategy to correct a common high-risk allele that is associated with age-related macular degeneration (AMD; rs1061170; NM_000186.3:c.1204T>C; NP_000177.2:p.His402Tyr) in the complement factor H (CFH) gene. Methods: A human embryonic kidney cell line (HEK293A) was engineered to contain the pathogenic risk variant for AMD (HEK293A-CFH). Several different base editor constructs (BE3, SaBE3, SaKKH-BE3, VQR-BE3, and Target-AID) and their respective single-guide RNA (sgRNA) expression cassettes targeting either the pathogenic risk variant allele in the CFH locus or the LacZ gene, as a negative control, were evaluated head-to-head for the incidence of a cytosine-to-thymine nucleotide correction. The base editor construct that showed appreciable editing activity was selected for further assessment in which the base-edited region was subjected to next-generation deep sequencing to quantify on-target and off-target editing efficacy. Results: The tandem use of the Target-AID base editor and its respective sgRNA demonstrated a base editing efficiency of facilitating a cytosine-to-thymine nucleotide correction in 21.5% of the total sequencing reads. Additionally, the incidence of insertions and deletions (indels) was detected in only 0.15% of the sequencing reads with virtually no off-target effects evident across the top 11 predicted off-target sites containing at least one cytosine in the activity window (n = 3, pooled amplicons). Conclusions: CRISPR-mediated base editing can be used to facilitate a permanent and stably inherited cytosine-to-thymine nucleotide correction of the rs1061170 SNP in the CFH gene with minimal off-target effects.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Edição de Genes/métodos , RNA Guia/genética , Sequência de Bases , Proteína 9 Associada à CRISPR/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Fator H do Complemento/genética , Fator H do Complemento/metabolismo , Citosina/metabolismo , Expressão Gênica , Células HEK293 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Óperon Lac , Degeneração Macular/genética , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Mutação , Plasmídeos/química , Plasmídeos/metabolismo , RNA Guia/metabolismo , Timina/metabolismo
14.
Ophthalmology ; 126(8): 1119-1130, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30910584

RESUMO

PURPOSE: To investigate which clinical measures influence whether an individual demonstrates earliest glaucomatous structural progression on peripapillary retinal nerve fiber layer (pRNFL) or macular ganglion cell-inner plexiform layer (mGCIPL). DESIGN: Prospective, longitudinal cohort study. PARTICIPANTS: Two hundred seventy-one eyes from 207 individuals with statistically significant evidence of glaucomatous progression on OCT Guided Progression Analysis (GPA) software were drawn from a total of 1271 eyes from 686 individuals categorized as glaucoma suspect or having early manifest glaucoma undergoing glaucoma surveillance. METHODS: Individuals demonstrating earliest evidence of longitudinal progression on mGCIPL GPA event analysis were compared with individuals demonstrating evidence of earliest longitudinal progression on pRNFL GPA event analysis. MAIN OUTCOME MEASURES: Correlation of OCT event change analysis with intraocular pressure (IOP), clinical variables, and baseline thickness of the pRNFL and mGCIPL. RESULTS: Intraocular pressure, baseline pRNFL thickness, baseline mGCIPL thickness, and systemic hypertension were associated with location of first progression. Eyes demonstrating earliest longitudinal progression on mGCIPL had significantly lower maximum-recorded pretreatment IOP (mean difference, 3.90 mmHg; 95% confidence interval [CI], 2.37-5.43 mmHg; P < 0.001). The interval between progression on pRNFL and progression on mGCIPL increased by 12.4 months for every 5-mmHg increase in IOP (95% CI, 10.32-15.72 months). Eyes demonstrating earliest longitudinal progression on mGCIPL showed significantly lower baseline average pRNFL thickness than eyes progressing on pRNFL first (mean difference, 7.07 µm; 95% CI, 4.38-9.77 µm; P < 0.001). Eyes progressing first on mGCIPL parameters were 3.03 times more likely to demonstrate a new paracentral field defect than eyes progressing first on pRNFL parameters (odds ratio, 3.03; 95% CI, 1.26-7.28; P = 0.01). CONCLUSIONS: Clinical features, particularly pretreatment IOP, influence whether structural glaucoma progression is detected earlier with mGCIPL or pRNFL imaging. These data support the usefulness of mGCIPL imaging in addition to pRNFL analysis for detection of glaucoma progression, particularly in patients with normal IOP.

15.
JAMA Ophthalmol ; 137(4): 348-355, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30653210

RESUMO

Importance: Both primary and secondary forms of childhood glaucoma have many distinct causative mechanisms, and in many cases a cause is not immediately clear. The broad phenotypic spectrum of secondary glaucoma, particularly in individuals with variants in FOXC1 or PITX2 genes associated with Axenfeld-Rieger syndrome, makes it more difficult to diagnose patients with milder phenotypes. These cases are occasionally classified and managed as primary congenital glaucoma. Objective: To investigate the prevalence of FOXC1 variants in participants with a suspected diagnosis of primary congenital glaucoma. Design, Setting, and Participants: Australian and Italian cohorts were recruited from January 1, 2007, through March 1, 2016. Australian individuals were recruited through the Australian and New Zealand Registry of Advanced Glaucoma and Italian individuals through the Genetic and Ophthalmology Unit of l'Azienda Socio-Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda in Milan, Italy. We performed exome sequencing, in combination with Sanger sequencing and multiplex ligation-dependent probe amplification, to detect variants of FOXC1 in individuals with a suspected diagnosis of primary congenital glaucoma established by their treating specialist. Data analysis was completed from June 2015 to November 2017. Main Outcome and Measures: Identification of single-nucleotide and copy number variants in FOXC1, along with phenotypic characterization of the individuals who carried them. Results: A total of 131 individuals with a suspected diagnosis of primary congenital glaucoma were included. The mean (SD) age at recruitment in the Australian cohort was 24.3 (18.1) years; 37 of 84 Australian participants (44.0%) were female, and 71 of 84 (84.5%) were of European ancestry. The mean (SD) age at recruitment was 22.5 (18.4) years in the Italian cohort; 21 of 47 Italian participants (44.7%) were female, and 45 of 47 (95.7%) were of European ancestry. We observed rare, predicted deleterious FOXC1 variants in 8 of 131 participants (6.1%), or 8 of 166 participants (4.8%) when including those explained by variants in CYP1B1. On reexamination or reinvestigation, all of these individuals had at least 1 detectable ocular and/or systemic feature associated with Axenfeld-Rieger syndrome. Conclusions and Relevance: These data highlight the genetic and phenotypic heterogeneity of childhood glaucoma and support the use of gene panels incorporating FOXC1 as a diagnostic aid, especially because clinical features of Axenfeld-Rieger syndrome can be subtle. Further replication of these results will be needed to support the future use of such panels.

17.
Sci Rep ; 9(1): 612, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679766

RESUMO

Mitochondrial haplogroups H1, H2 and UK have previously been reported to be associated with proliferative diabetic retinopathy (PDR) in Caucasian patients with diabetes. We aimed to replicate this finding with a larger sample and expand the analysis to include different severities of DR, and diabetic macular edema (DME). Caucasian participants (n = 2935) with either type 1 or type 2 diabetes from the Australian Registry of Advanced Diabetic Retinopathy were enrolled in this study. Twenty-two mitochondrial single nucleotide polymorphisms were genotyped by MassArray and haplogroups reconstructed using Haplogrep. Chi square tests and logistic regressions were used to test associations between haplogroup and DR phenotypes including any DR, non-proliferative DR (NPDR), proliferative DR (PDR) and DME. After stratifying the samples in type 1 and type 2 diabetes groups, and adjusting for sex, age, diabetes duration, concurrent HbA1c and hypertension, neither haplogroups H1, H2, UK, K or JT were associated with any DR, NPDR, PDR or DME.

19.
Asia Pac J Ophthalmol (Phila) ; 8(3): 224-228, 2019 May-Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30596227

RESUMO

PURPOSE: It has been suggested that female sex steroids have neuroprotective properties that may reduce risk of glaucoma in premenopausal women. In this study, we explored the associations of optic disc measures with female reproductive factors in a population of young women. DESIGN: Cohort study. METHODS: Young women (n = 494; age range, 18-22 years) were recruited as part of the Western Australian Pregnancy Cohort (Raine) Study. Information on age at menarche, parity, and use of hormonal contraceptives were obtained from questionnaires. Participants underwent an eye examination, including spectral-domain optical coherence tomography imaging, to obtain optic disc parameters. RESULTS: Women who had given birth at least once (parous women; n = 10) had larger vertical neuroretinal rim widths (P < 0.001) than nulliparous women (n = 484) after correcting for use of hormonal contraceptives, intraocular pressure, refractive error, and family history of glaucoma. Furthermore, vertical and horizontal cup-to-disc ratios, which are inherently related to neuroretinal rim width, were found to be smaller among parous women compared with nulliparous women (both P < 0.001). Age at menarche and use of hormonal contraceptives were not significantly associated with any optic disc parameters. CONCLUSIONS: We found limited evidence that female reproductive factors were related with optic disc parameters during young adulthood. The association between parity and optic disc parameter, though significant, should be further investigated given the small number of parous women in the current sample. Future follow-ups of this cohort will allow us to explore for any associations of these factors with optic disc parameters and glaucoma risk at an older age.


Assuntos
Glaucoma/diagnóstico , Pressão Intraocular/fisiologia , Disco Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/diagnóstico , Reprodução , Adolescente , Feminino , Seguimentos , Glaucoma/fisiopatologia , Humanos , Doenças do Nervo Óptico/fisiopatologia , Estudos Retrospectivos , Inquéritos e Questionários , Fatores de Tempo , Tomografia de Coerência Óptica , Tonometria Ocular , Campos Visuais , Adulto Jovem
20.
Mol Ther Nucleic Acids ; 14: 184-191, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30594894

RESUMO

Gain-of-function studies often require the tedious cloning of transgene cDNA into vectors for overexpression beyond the physiological expression levels. The rapid development of CRISPR/Cas technology presents promising opportunities to address these issues. Here, we report a simple, cloning-free method to induce gene expression at an endogenous locus using CRISPR/Cas9 activators. Our strategy utilizes synthesized sgRNA expression cassettes to direct a nuclease-null Cas9 complex fused with transcriptional activators (VP64, p65, and Rta) for site-specific induction of endogenous genes. This strategy allows rapid initiation of gain-of-function studies in the same day. Using this approach, we tested two CRISPR activation systems, dSpCas9VPR and dSaCas9VPR, for induction of multiple genes in human and rat cells. Our results showed that both CRISPR activators allow efficient induction of six different neural development genes (CRX, RORB, RAX, OTX2, ASCL1, and NEUROD1) in human cells, whereas the rat cells exhibit more variable and less-efficient levels of gene induction, as observed in three different genes (Ascl1, Neurod1, Nrl). Altogether, this study provides a simple method to efficiently activate endogenous gene expression using CRISPR/Cas9 activators, which can be applied as a rapid workflow to initiate gain-of-function studies for a range of molecular- and cell-biology disciplines.

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