Polygenic Risk Scores Driving Clinical Change in Glaucoma.

Glaucoma is a clinically heterogeneous disease and the world's leading cause of irreversible blindness. Therapeutic intervention can prevent blindness but relies on early diagnosis, and current clinical risk factors are limited in their ability to predict who will develop sight-threatening glaucoma. The high heritability of glaucoma makes it an ideal substrate for genetic risk prediction, with the bulk of risk being polygenic in nature. Here, we summarize the foundations of glaucoma genetic risk, the development of polygenic risk prediction instruments, and emerging opportunities for genetic risk stratification. Although challenges remain, genetic risk stratification will significantly improve glaucoma screening and management.

Healthcare professionals' knowledge and attitudes towards polygenic risk testing for glaucoma.

BACKGROUND: Effective clinical implementation of polygenic risk testing for glaucoma relies on healthcare professionals' attitudes and knowledge of the test. Given the emerging applications of the test, it will likely impact a range of healthcare professionals and will require competency in polygenic risk scores concepts for all those involved in patient care. To our knowledge, this is the first study to assess healthcare professionals' views towards polygenic testing for glaucoma. METHODS: An online cross-sectional questionnaire was distributed to healthcare professionals via relevant professional organisations in Australia. The questionnaire assessed experience and confidence with genetic testing, glaucoma and genetic knowledge, recommendations for the tests, and factors affecting the decision. RESULTS: A total of 94 participants completed the questionnaire. The sample was composed of ophthalmologists (36%), optometrists (21%), orthoptists (17%), general practitioners (16%) and clinical geneticists/genetic counsellors (10%). Although familiarity with polygenic risk scores for glaucoma was low overall (11%), the majority reported a positive attitude towards recommending testing based on known risk factors such as family history (91%) and older age (57%). Over 95% indicated that ophthalmologists would be the most appropriate group to order polygenic risk testing and communicate results. The majority felt they would benefit from more training on polygenic risk scores (93%). CONCLUSIONS: Our findings indicated that multiple groups of healthcare professionals were neither familiar nor confident with the concept of glaucoma polygenic risk testing, and identified training and education needs to support the implementation of testing into clinical practice.

High Polygenic Risk Is Associated with Earlier Initiation and Escalation of Treatment in Early Primary Open-Angle Glaucoma.

PURPOSE: To assess the association between a glaucoma polygenic risk score (PRS) and treatment outcomes in primary open-angle glaucoma. DESIGN: Prospective, observational cohort study. PARTICIPANTS: Participants from the Progression Risk of Glaucoma: Relevant SNPs with Significant Association Study were divided into a cohort with suspect glaucoma who were treatment naive at enrollment and one with early manifest and suspect glaucoma receiving treatment at enrollment. METHODS: A per-allele weighted glaucoma PRS was calculated for 1107 participants. Multivariable mixed-effects Cox proportional regression analysis assessed the association between PRS and time to commencement of intraocular pressure (IOP)-lowering therapy in 416 patients with suspect glaucoma who were treatment naive at study enrollment. Secondary analysis evaluated the association between PRS and escalation of IOP-lowering therapy among 691 patients with suspect and early manifest glaucoma who were receiving IOP-lowering therapy at enrollment. MAIN OUTCOME MEASURES: Commencement or escalation of IOP-lowering therapy. RESULTS: A higher PRS was associated with a greater risk of commencing IOP-lowering therapy within 5 years (hazard ratio [HR], 1.45 per 1 standard deviation [/SD]; 95% confidence interval [CI], 1.27-1.62; P < 0.001). Participants in the upper population-based quintile showed a 3.3 times greater risk of commencing therapy by 5 years than those in the lowest quintile (HR, 3.30; 95% CI, 1.63-6,70; P < 0.001) and a 5.4 times greater risk of commencing IOP-lowering therapy by 2 years than the those in the lowest quintile (HR, 5.45; 95% CI, 2.08-14.25; P < 0.001). A higher PRS was associated with a greater risk of treatment escalation among patients receiving treatment at enrollment (HR, 1.19/SD; 95% CI, 1.09-1.31; P < 0.001). In combined analysis of all participants, participants in the top population-based quintile were at 2.3 times greater risk of requiring initiation or escalation of IOP-lowering therapy than those in the lowest quintile (HR, 2.33; 95% CI, 1.75-3.01; P < 0.001). CONCLUSIONS: This study demonstrated novel associations between glaucoma polygenic risk and risk of commencement or escalation of IOP-lowering therapy, building on previous work highlighting the potential clinical usefulness of genetic risk stratification in glaucoma. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

The Role of Tocilizumab in Glucocorticoid Resistant Giant Cell Arteritis: A Case Series and Literature Review.

BACKGROUND: Glucocorticoid-resistant giant cell arteritis (GCA) describes a subgroup of patients whose visual acuity further declines despite immediate administration of high-dose intravenous glucocorticoids. Tocilizumab, a recombinant humanized anti-interleukin-6 receptor monoclonal antibody may be used as "rescue" therapy in these cases but requires more research. METHODS: We present a literature review on tocilizumab as rescue therapy and a retrospective case series of 5 consecutive glucocorticoid (GC) resistant, temporal artery biopsy (TAB)-positive [corrected] patients. RESULTS: The use of tocilizumab as rescue therapy for GC-resistant GCA is limited to 3 case reports. Two cases saw visual acuity improvement in the newly affected contralateral eye after 8 mg/kg of intravenous tocilizumab (from 6/60 to 6/15 in one case and hand motion to 6/6 in another). The third described stabilization and prevention of further best-corrected visual acuity (BCVA) decline. All 5 of our patients presented with acute monocular vision loss. BCVA ranged from 6/12 to light perception (LP). All patients were promptly commenced on 1 g intravenous methylprednisolone daily. Weekly 162 mg of subcutaneous tocilizumab was commenced once contralateral eye involvement was noted. Tocilizumab resulted in bilateral BCVA gains in 2 cases, recovery of the contralateral eye in one, and no effect in the remaining 2 cases. BCVA recovery was no light perception to 6/6 after 6 weeks of tocilizumab. Tocilizumab had no effect in cases with severe vision loss and high C-reactive protein on presentation. CONCLUSIONS: We agree with existing hypothesis that tocilizumab likely prevents a "pending" central retinal artery occlusion by maintaining retinal vasculature perfusion. Our case series suggests that there is a role for tocilizumab as "rescue" therapy for GC-resistant GCA, where vision loss would otherwise be imminent.

Pallid Disc Oedema in a Young Patient: Clinical and Diagnostic Challenge.

A mid-thirties male with end-stage renal failure receiving haemodialysis on a background of four failed renal transplants, post-transplant lymphoproliferative disorder,and autonomic dysfunction presented with acute vision change in his left eye. Over days his vision in that eye deteriorated from 20/25 to no light perception. Given his complex medical background he was extensively investigated for infective, inflammatory, infiltrative and vasculitic aetiologies to explain acute vision loss with pallid disc swelling. A final diagnosis of non-arteritic anterior ischaemic optic neuropathy secondary to refractive hypotension and haemodialysis was reached.

A novel GSN variant outside the G2 calcium-binding domain associated with Amyloidosis of the Finnish type.

Gelsolin (GSN) variants have been implicated in amyloidosis of the Finnish type. This case series reports a novel GSN:c.1477T>C,p.(Trp493Arg) variant in a family with ocular and systemic features consistent with Finnish Amyloidosis. Exome sequencing performed on affected individuals from two families manifesting cutis laxa and polymorphic corneal stromal opacities demonstrated the classic GSN:c.654G>A,p.Asp214Asn variant in single affected individual from one family, and a previously undocumented GSN:c.1477T>C variant in three affected first-degree relatives from a separate family. Immunohistochemical studies on corneal tissue from a proband with the c.1477T>C variant identified gelsolin protein within histologically defined corneal amyloid deposits. This study reports a novel association between the predicted pathogenic GSN:c.1477T>C variant and amyloidosis of the Finnish type, and is the first to provide functional evidence of a pathological GSN variant at a locus distant to the critical G2 calcium-binding region, resulting in the phenotype of amyloidosis of the Finnish type.

Genome-wide association analysis of 95 549 individuals identifies novel loci and genes influencing optic disc morphology.

Optic nerve head morphology is affected by several retinal diseases. We measured the vertical optic disc diameter (DD) of the UK Biobank (UKBB) cohort (N = 67 040) and performed the largest genome-wide association study (GWAS) of DD to date. We identified 81 loci (66 novel) for vertical DD. We then replicated the novel loci in International Glaucoma Genetic Consortium (IGGC, N = 22 504) and European Prospective Investigation into Cancer-Norfolk (N = 6005); in general the concordance in effect sizes was very high (correlation in effect size estimates 0.90): 44 of the 66 novel loci were significant at P < 0.05, with 19 remaining significant after Bonferroni correction. We identified another 26 novel loci in the meta-analysis of UKBB and IGGC data. Gene-based analyses identified an additional 57 genes. Human ocular tissue gene expression analysis showed that most of the identified genes are enriched in optic nerve head tissue. Some of the identified loci exhibited pleiotropic effects with vertical cup-to-disc ratio, intraocular pressure, glaucoma and myopia. These results can enhance our understanding of the genetics of optic disc morphology and shed light on the genetic findings for other ophthalmic disorders such as glaucoma and other optic nerve diseases.

Cardiovascular Disease Predicts Structural and Functional Progression in Early Glaucoma.

PURPOSE: To investigate the association between cardiovascular disease and baseline structural defects and disease progression in glaucoma. DESIGN: Prospective, longitudinal study of preperimetric and perimetric glaucoma. PARTICIPANTS: Two thousand six hundred twenty-eight eyes from 1314 participants recruited to the Progression Risk of Glaucoma: Relevant SNPs with Significant Association (PROGRESSA) study were evaluated for baseline and longitudinal structural thinning using spectral-domain OCT and for visual field progression on Humphrey visual field (HVF) assessment. METHODS: Patients were classified as either predominantly macula ganglion cell-inner plexiform layer (mGCIPL), predominantly peripapillary retinal nerve fiber layer (pRNFL), or both mGCIPL and pRNFL structural change at enrollment, and then evaluated for longitudinal OCT or HVF progression. Cardiovascular disease and medication characteristics of the participants were compared with a reference group of stable patients. MAIN OUTCOME MEASURES: OCT and HVF baseline status and longitudinal progression. RESULTS: After accounting for age and cardiovascular characteristics, patients with predominantly mGCIPL thinning at baseline showed a higher prevalence of hypertension (odds ratio [OR], 2.70; 95% confidence interval [CI], 1.66-4.41; P < 0.001), antihypertensive use (OR, 2.03; 95% CI, 1.20-3.46; P = 0.008), and statin use (OR, 1.98; 95% CI, 1.07-3.66; P = 0.029) than reference patients. Patients with predominantly pRNFL thinning exhibited a comparable prevalence of cardiovascular disease or medication with reference patients. Review of longitudinal OCT and HVF data (mean follow-up, 5.34 ± 1.29 years) showed that hypertension was associated with an increased risk of both OCT (OR, 1.79; 95% CI, 1.17-2.75; P = 0.006) and HVF progression (OR, 1.92; 95% CI, 1.18-3.15; P = 0.013). A 1-standard deviation (approximately 21 mmHg) increase in systolic blood pressure at baseline was associated with a greater risk of OCT progression (OR, 1.27; 95% CI, 1.01-1.63; P = 0.041) and HVF progression (OR, 1.32; 95% CI, 1.01-1.73; P = 0.043). The association between systolic blood pressure and structural progression was comparable to that observed between intraocular pressure and structural progression (OR, 1.30; 95% CI, 1.01-1.67; P = 0.039). CONCLUSIONS: Cardiovascular disease is an important risk factor for glaucoma progression.

Corneal Stiffness Parameters Are Predictive of Structural and Functional Progression in Glaucoma Suspect Eyes.

PURPOSE: To investigate corneal stiffness parameters (SPs) as predictors of future progression risk in glaucoma suspect eyes. DESIGN: Prospective, longitudinal study. PARTICIPANTS: Three hundred seventy-one eyes from 228 primary open-angle glaucoma suspects, based on optic disc appearance, with normal baseline Humphrey Visual Field (HVF; Carl Zeiss Meditec) results. METHODS: Baseline corneal SPs were measured using Corvis ST (Oculus Optikgeräte GmbH). Participants were followed up every 6 months with clinical examination, HVF testing, and OCT. The baseline SP at first applanation (SP-A1) and highest concavity predicted the prospective outcome measures. MAIN OUTCOME MEASURES: Structural progression was measured by the OCT rate of thinning of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL). Functional progression was assessed by permutation analysis of pointwise linear regression criteria on HVF testing. RESULTS: Stiffness parameters correlated positively with central corneal thickness (CCT), which was adjusted for in all analyses. A higher SP-A1, suggestive of a stiffer cornea, was associated with a faster rate of RNFL thinning (P < 0.001), synergistic with thinner CCT (P = 0.004) over a mean follow-up of 4.2 years. Eyes with higher SP-A1 and thinner CCT (thin and stiff corneas) showed accelerated RNFL thinning by 0.72 µm/year relative to eyes with lower SP-A1 and thicker CCT (95% confidence interval [CI], 0.17-1.28; P = 0.011) and were at 2.9-fold higher likelihood of fast RNFL progression of more than 1 µm/year (95% CI, 1.4-6.1; P = 0.006). Consistent results also were observed with GCIPL thinning. Furthermore, a higher SP-A1 was associated with a greater risk of visual field progression (P = 0.002), synergistic with thinner CCT (P = 0.010). Eyes with higher SP-A1 and thinner CCT were at 3.7-fold greater risk of visual field progression relative to eyes with thicker CCT and lower SP-A1 (95% CI, 1.3-10.5; P = 0.014). CONCLUSIONS: Glaucoma suspect eyes with higher corneal SPs and lower CCT, suggestive of thin and stiff corneas, are at greater risk of progression. Corneal SPs seem to act synergistically with CCT as risk factors for glaucoma progression.

Vaccination of Macaques with DNA Followed by Adenoviral Vectors Encoding Simian Immunodeficiency Virus (SIV) Gag Alone Delays Infection by Repeated Mucosal Challenge with SIV.

Vaccines aimed at inducing T cell responses to protect against human immunodeficiency virus (HIV) infection have been under development for more than 15 years. Replication-defective adenovirus (rAd) vaccine vectors are at the forefront of this work and have been tested extensively in the simian immunodeficiency virus (SIV) challenge macaque model. Vaccination with rAd vectors coding for SIV Gag or other nonenvelope proteins induces T cell responses that control virus load but disappointingly is unsuccessful so far in preventing infection, and attention has turned to inducing antibodies to the envelope. However, here we report that Mauritian cynomolgus macaques (MCM), Macaca fascicularis, vaccinated with unmodified SIV gag alone in a DNA prime followed by an rAd boost exhibit increased protection from infection by repeated intrarectal challenge with low-dose SIVmac251. There was no evidence of infection followed by eradication. A significant correlation was observed between cytokine expression by CD4 T cells and delayed infection. Vaccination with gag fused to the ubiquitin gene or fragmented, designed to increase CD8 magnitude and breadth, did not confer resistance to challenge or enhance immunity. On infection, a significant reduction in peak virus load was observed in all vaccinated animals, including those vaccinated with modified gag These findings suggest that a nonpersistent viral vector vaccine coding for internal virus proteins may be able to protect against HIV type 1 (HIV-1) infection. The mechanisms are probably distinct from those of antibody-mediated virus neutralization or cytotoxic CD8 cell killing of virus-infected cells and may be mediated in part by CD4 T cells.IMPORTANCE The simian immunodeficiency virus (SIV) macaque model represents the best animal model for testing new human immunodeficiency virus type 1 (HIV-1) vaccines. Previous studies employing replication-defective adenovirus (rAd) vectors that transiently express SIV internal proteins induced T cell responses that controlled virus load but did not protect against virus challenge. However, we show for the first time that SIV gag delivered in a DNA prime followed by a boost with an rAd vector confers resistance to SIV intrarectal challenge. Other partially successful SIV/HIV-1 protective vaccines induce antibody to the envelope and neutralize the virus or mediate antibody-dependent cytotoxicity. Induction of CD8 T cells which do not prevent initial infection but eradicate infected cells before infection becomes established has also shown some success. In contrast, the vaccine described here mediates resistance by a different mechanism from that described above, which may reflect CD4 T cell activity. This could indicate an alternative approach for HIV-1 vaccine development.

An Intraocular Pressure Polygenic Risk Score Stratifies Multiple Primary Open-Angle Glaucoma Parameters Including Treatment Intensity.

PURPOSE: To examine the combined effects of common genetic variants associated with intraocular pressure (IOP) on primary open-angle glaucoma (POAG) phenotype using a polygenic risk score (PRS) stratification. DESIGN: Cross-sectional study. PARTICIPANTS: For the primary analysis, we examined the glaucoma phenotype of 2154 POAG patients enrolled in the Australian and New Zealand Registry of Advanced Glaucoma, including patients recruited from the United Kingdom. For replication, we examined an independent cohort of 624 early POAG patients. METHODS: Using IOP genome-wide association study summary statistics, we developed a PRS derived solely from IOP-associated variants and stratified POAG patients into 3 risk tiers. The lowest and highest quintiles of the score were set as the low- and high-risk groups, respectively, and the other quintiles were set as the intermediate risk group. MAIN OUTCOME MEASURES: Clinical glaucoma phenotype including maximum recorded IOP, age at diagnosis, number of family members affected by glaucoma, cup-to-disc ratio, visual field mean deviation, and treatment intensity. RESULTS: A dose-response relationship was found between the IOP PRS and the maximum recorded IOP, with the high genetic risk group having a higher maximum IOP by 1.7 mmHg (standard deviation [SD], 0.62 mmHg) than the low genetic risk group (P = 0.006). Compared with the low genetic risk group, the high genetic risk group had a younger age of diagnosis by 3.7 years (SD, 1.0 years; P < 0.001), more family members affected by 0.46 members (SD, 0.11 members; P < 0.001), and higher rates of incisional surgery (odds ratio, 1.5; 95% confidence interval, 1.1-2.0; P = 0.007). No statistically significant difference was found in mean deviation. We further replicated the maximum IOP, number of family members affected by glaucoma, and treatment intensity (number of medications) results in the early POAG cohort (P ≤ 0.01). CONCLUSIONS: The IOP PRS was correlated positively with maximum IOP, disease severity, need for surgery, and number of affected family members. Genes acting via IOP-mediated pathways, when considered in aggregate, have clinically important and reproducible implications for glaucoma patients and their close family members.

Updating the model of eye care for Aboriginal populations in remote Central Australia.

Eye disease is the third-highest contributor towards health inequality for Aboriginal Australians. Understanding how the Central Australian ophthalmology service addresses complexities of remote eye care is crucial in understanding how expansion can meet current and future needs. The present study analyses findings from the MEDLINE database and Governmental reports, and descriptive information from stakeholders in Central Australia and the Australian Department of Health. We describe the current Central Australian ophthalmology model at three levels; (a) the healthcare service level (specialized primary care, local/outreach optometry and ophthalmology services, and intensive extended surgical weeks), (b) the community level (local community staff, clinics and initiatives, and eye "champions" and mutual support), and (c) the healthcare system level (federal and state government, and private funding). We conclude that building full-time specialist availability, and system-wide approaches to increase patient utilisation, will facilitate overcoming barriers of remoteness, and create enduring improvements in Central Australian eye care and health-inequality.

Using Icare HOME tonometry for follow-up of patients with open-angle glaucoma before and after selective laser trabeculoplasty.

IMPORTANCE: Monitoring the results of selective laser trabeculoplasty (SLT) on intraocular pressure (IOP) using a home rebound tonometry. BACKGROUND: To evaluate the role of Icare HOME tonometry in open-angle glaucoma patients being treated with SLT. DESIGN: A clinic-based prospective case study. PARTICIPANTS: Fourteen eyes from 14 patients diagnosed with primary open-angle glaucoma were recruited. METHODS: The trabecular meshwork of each eye was treated 360° with a frequency-doubled Q-switched Nd:YAG laser. IOP was measured four times a day for a week before and after SLT. On the day of SLT, the patients were required to measure the IOP in the evening to record any IOP spikes. MAIN OUTCOME MEASURES: The use of Icare HOME in following up patients post-laser trabeculoplasty without the need for clinic attendance. RESULTS: Icare HOME recorded a significant reduction of 5.12 mmHg in the mean IOP post-SLT (95% confidence interval [CI] 3.75-6.50 mmHg, P < .001). The maximum IOP was also reduced by 6.14 mmHg (95% CI 3.07-9.21, P < .001) with no IOP spikes recorded post-SLT. There was a reduction in IOP fluctuation post-SLT by 1.07 mmHg (95% CI 0.24-1.89 mmHg, P = .021). No adverse effects for using the Icare HOME were reported by the study participants. CONCLUSIONS AND RELEVANCE: This methodology could be highly useful for facilitating safe follow-up of patients residing in remote and rural areas, thus reducing healthcare cost with better information on IOP.

Analysis of Early Cone Dysfunction in an In Vivo Model of Rod-Cone Dystrophy.

Retinitis pigmentosa (RP) is a generic term for a group of genetic diseases characterized by loss of rod and cone photoreceptor cells. Although the genetic causes of RP frequently only affect the rod photoreceptor cells, cone photoreceptors become stressed in the absence of rods and undergo a secondary degeneration. Changes in the gene expression profile of cone photoreceptor cells are likely to occur prior to observable physiological changes. To this end, we sought to achieve greater understanding of the changes in cone photoreceptor cells early in the degeneration process of the Rho-/- mouse model. To account for gene expression changes attributed to loss of cone photoreceptor cells, we normalized PCR in the remaining number of cones to a cone cell reporter (OPN1-GFP). Gene expression profiles of key components involved in the cone phototransduction cascade were correlated with tests of retinal cone function prior to cell loss. A significant downregulation of the photoreceptor transcription factor Crx was observed, which preceded a significant downregulation in cone opsin transcripts that coincided with declining cone function. Our data add to the growing understanding of molecular changes that occur prior to cone dysfunction in a model of rod-cone dystrophy. It is of interest that gene supplementation of CRX by adeno-associated viral vector delivery prior to cone cell loss did not prevent cone photoreceptor degeneration in this mouse model.

Comparison of Serologic Assays for Middle East Respiratory Syndrome Coronavirus.

Middle East respiratory syndrome coronavirus (MERS-CoV) was detected in humans in 2012. Since then, sporadic outbreaks with primary transmission through dromedary camels to humans and outbreaks in healthcare settings have shown that MERS-CoV continues to pose a threat to human health. Several serologic assays for MERS-CoV have been developed globally. We describe a collaborative study to investigate the comparability of serologic assays for MERS-CoV and assess any benefit associated with the introduction of a standard reference reagent for MERS-CoV serology. Our study findings indicate that, when possible, laboratories should use a testing algorithm including >2 tests to ensure correct diagnosis of MERS-CoV. We also demonstrate that the use of a reference reagent greatly improves the agreement between assays, enabling more consistent and therefore more meaningful comparisons between results.

Characterization of Antibody Interactions with the G Protein of Vesicular Stomatitis Virus Indiana Strain and Other Vesiculovirus G Proteins.

Vesicular stomatitis virus Indiana strain G protein (VSVind.G) is the most commonly used envelope glycoprotein to pseudotype lentiviral vectors (LV) for experimental and clinical applications. Recently, G proteins derived from other vesiculoviruses (VesG), for example, Cocal virus, have been proposed as alternative LV envelopes with possible advantages over VSVind.G. Well-characterized antibodies that recognize VesG will be useful for vesiculovirus research, development of G protein-containing advanced therapy medicinal products (ATMPs), and deployment of VSVind-based vaccine vectors. Here, we show that one commercially available monoclonal antibody, 8G5F11, binds to and neutralizes G proteins from three strains of VSV, as well as Cocal and Maraba viruses, whereas the other commercially available monoclonal anti-VSVind.G antibody, IE9F9, binds to and neutralizes only VSVind.G. Using a combination of G protein chimeras and site-directed mutations, we mapped the binding epitopes of IE9F9 and 8G5F11 on VSVind.G. IE9F9 binds close to the receptor binding site and competes with soluble low-density lipoprotein receptor (LDLR) for binding to VSVind.G, explaining its mechanism of neutralization. In contrast, 8G5F11 binds close to a region known to undergo conformational changes when the G protein moves to its postfusion structure, and we propose that 8G5F11 cross-neutralizes VesGs by inhibiting this.IMPORTANCE VSVind.G is currently regarded as the gold-standard envelope glycoprotein to pseudotype lentiviral vectors. However, recently other G proteins derived from vesiculoviruses have been proposed as alternative envelopes. Here, we investigated two commercially available anti-VSVind.G monoclonal antibodies for their ability to cross-react with other vesiculovirus G proteins, identified the epitopes they recognize, and explored their neutralization activity. We have identified 8G5F11, for the first time, as a cross-neutralizing antibody against several vesiculovirus G proteins. Furthermore, we elucidated the two different neutralization mechanisms employed by these two monoclonal antibodies. Understanding how cross-neutralizing antibodies interact with other G proteins may be of interest in the context of host-pathogen interaction and coevolution, as well as providing the opportunity to modify the G proteins and improve G protein-containing medicinal products and vaccine vectors.

Macular Ganglion Cell-Inner Plexiform Layer Loss Precedes Peripapillary Retinal Nerve Fiber Layer Loss in Glaucoma with Lower Intraocular Pressure.

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.

Long-term survival rates of patients undergoing vitrectomy for diabetic retinopathy in an Australian population: a population-based audit.

IMPORTANCE: Five-year survival rates in patients undergoing vitrectomy for diabetic retinopathy (DR) vary from 68% to 95%. No study has been conducted in an Australian population. BACKGROUND: We aimed to determine the survival rates of patients undergoing diabetic vitrectomy in an Australian population. DESIGN: Retrospective audit, tertiary centre hospitals and private practices. PARTICIPANTS: All individuals in South Australia and the Northern Territory who underwent their first vitrectomy for diabetic complications between January 1, 2007 and December 31, 2011. METHODS: An audit of all eligible participants has been completed previously. Survival status as of July 6, 2018 and cause of death were obtained using SA/NT DataLink. Kaplan-Meier survival curves and multivariate cox-regressions were used to analyse survival rates and identify risk factors for mortality. MAIN OUTCOME MEASURES: Five-, seven- and nine-year survival rates. RESULTS: The 5-, 7- and 9-year survival rates were 84.4%, 77.9% and 74.7%, respectively. The most common cause of death was cardiovascular disease. Associated with increased mortality independent of age were Indigenous ethnicity (HR = 2.04, 95% confidence interval [CI]: 1.17-3.57, P = 0.012), chronic renal failure (HR = 1.76, 95% CI: 1.07-2.89, P = 0.026) and renal failure requiring dialysis (HR = 2.32, 95% CI: 1.25-4.32, P = 0.008). CONCLUSIONS AND RELEVANCE: Long-term survival rates after diabetic vitrectomy in Australia are similar to rates reported in other populations. Indigenous ethnicity and chronic renal failure were the most significant factors associated with long-term mortality. This information can guide allocation of future resources to improve the prognosis of these high risk groups.

Visual outcomes following vitrectomy for diabetic retinopathy amongst Indigenous and non-Indigenous Australians in South Australia and the Northern Territory.

IMPORTANCE: Visual outcomes following diabetic vitrectomy have not previously been studied in an Australian population. BACKGROUND: This analysis aimed to determine the rate of, and factors associated with visual success following diabetic vitrectomy performed for Indigenous and non-Indigenous Australians, and investigate factors predisposing to early progression to diabetic retinopathy (DR) requiring vitrectomy. DESIGN: Retrospective, population-based audit. PARTICIPANTS: All patients undergoing vitrectomy for the complications of DR in South Australia (SA) and the Northern Territory (NT) between 2007 and 2011. METHODS: Medical records were audited and data collected, including demographics, diabetic history, past treatment for DR, indication for vitrectomy and visual acuity pre and postoperatively. MAIN OUTCOME MEASURES: Visual success (gain of ≥15 ETDRS letters) at 6 and 12 months, postoperatively. RESULTS: A total of 495 diabetic vitrectomies, for 404 eyes of 335 patients were performed in SA and NT between 2007 and 2011. 77 (23%) patients requiring diabetic vitrectomy were Indigenous Australians. 87% of patients undergoing diabetic vitrectomy had stable or improved vision at 1 year, postoperatively. There was no significant difference between indigenous and non-indigenous eyes achieving visual success (P = 0.929). Timely preoperative laser treatment (P = 0.03) and preoperative visual acuity (P = 0.01) were the predominant factors associated with visual success. CONCLUSIONS AND RELEVANCE: Indigenous patients are just as likely to have improved vision following diabetic vitrectomy as non-Indigenous Australians. However, the small subset of indigenous patients with blind eyes prior to vitrectomy are significantly less likely to improve from surgery. The underlying factors associated with poor outcomes in this group requires further exploration.

Gene Therapy for Color Blindness.

Achromatopsia is a rare congenital cause of vision loss due to isolated cone photoreceptor dysfunction. The most common underlying genetic mutations are autosomal recessive changes in CNGA3, CNGB3, GNAT2, PDE6H, PDE6C, or ATF6. Animal models of Cnga3, Cngb3, and Gnat2 have been rescued using AAV gene therapy; showing partial restoration of cone electrophysiology and integration of this new photopic vision in reflexive and behavioral visual tests. Three gene therapy phase I/II trials are currently being conducted in human patients in the USA, the UK, and Germany. This review details the AAV gene therapy treatments of achromatopsia to date. We also present novel data showing rescue of a Cnga3-/- mouse model using an rAAV.CBA.CNGA3 vector. We conclude by synthesizing the implications of this animal work for ongoing human trials, particularly, the challenge of restoring integrated cone retinofugal pathways in an adult visual system. The evidence to date suggests that gene therapy for achromatopsia will need to be applied early in childhood to be effective.