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PURPOSE: To describe in detail the phenotype of a patient with enhanced S-cone syndrome. METHODS: We describe a 13-year-old boy who presented with blurred vision, vitreous cells, cystoid macular edema refractory to steroid treatment, and a negative uveitic workup. The patient underwent a complete ophthalmic examination, full-field electroretinograms (ffERG), automatic static perimetry and multimodal imaging with spectral domain optical coherence tomography, and adaptive optics scanning laser ophthalmoscopy (AOSLO). RESULTS: Spectral domain optical coherence tomography demonstrated cystoid macular edema and a hyperthick, delaminated midperipheral retina. Fluorescein angiography did not demonstrate macular leakage. Rod-mediated ffERGs were undetectable, and there was a supernormal response to short-wavelength stimuli compared with photopically matched longer wavelengths of light consistent with enhanced S-cone syndrome. Gene screening was positive for compound heterozygous mutations NR2E3: a known (c.119-2 A>C) and a novel (c.119-1G>A) mutation. By perimetry, sensitivities were normal or above normal for short-wavelength stimuli; there was no detectable rod-mediated vision. AOSLO demonstrated higher than normal cone densities in the perifoveal retina and evidence for smaller outer segment cone diameters. CONCLUSION: Evidence for supernumerary cones (at least twice the normal complement) by AOSLO and spectral domain optical coherence tomography was associated with supernormal S-cone sensitivities and electroretinogram responses confirming previous in vivo findings in postmortem human specimens. Smaller than normal cones in enhanced S-cone syndrome may represent “hybrid” photoreceptors analogous to the rd7/rd7 murine model of the disease.

To describe in detail the retinal phenotype of LAMP2-associated Danon disease.Three LAMP2-positive patients from two unrelated families were studied with spectral-domain optical coherence tomography and with short-wavelength and near-infrared fundus autofluorescence (FAF) imaging. Visual function was measured with full-field electroretinography and chromatic perimetry. A patient with choroideremia was also studied for comparison.A 45-year-old LAMP2-heterozygous woman, her 21-year-old hemizygous son, and an unrelated heterozygous 60-year-old woman had normal visual acuities. Central spectral-domain optical coherence tomographies were grossly normal in the younger two patients (mother and son). The oldest patient showed a tenuous interdigitation signal, interruptions of the inner segment ellipsoid zone band, and parafoveal outer nuclear layer thinning. Quantitatively, all patients had shorter than normal ellipsoid zone to retinal pigment epithelium distance in pericentral retina, normal at the foveola. A speckled hypoautofluorescence pattern on short-wavelength FAF contrasted with grossly abnormal near-infrared FAF in the heterozygous carriers. The oldest patient had reduced full-field electroretinography amplitudes (to ∼50% of normal) for rod- and cone-mediated responses and her perimetry showed severe rod dysfunction but substantial cone function. A disproportionate loss of the near-infrared FAF compared with the short-wavelength FAF, predominantly outer segment changes, and severe rod dysfunction with preserved cone function was similarly documented in a 9-year-old choroideremia hemizygous patient.A disproportionate loss of the near-infrared FAF signal compared with the short-wavelength FAF signal, outer segment abnormalities, and severe rod dysfunction but relatively preserved cone vision suggests a stereotypical pattern of primary retinal pigment epithelial or parallel retinal pigment epithelial + photoreceptor disease in Danon disease.

Gene regulation in embryonic stem cells (ESCs) has been extensively studied at the epigenetic-transcriptional level, but not at the posttranscriptional level. Pumilio (Pum) proteins are among the few known translational regulators required for stem-cell maintenance in invertebrates and plants. Here we report the essential function of two murine Pum proteins, Pum1 and Pum2, in ESCs and early embryogenesis. Pum1/2 double-mutant ESCs display severely reduced self-renewal and differentiation, and Pum1/2 double-mutant mice are developmentally delayed at the morula stage and lethal by embryonic day 8.5. Remarkably, Pum1-deficient ESCs show increased expression of pluripotency genes but not differentiation genes, whereas Pum2-deficient ESCs show decreased pluripotency markers and accelerated differentiation. Thus, despite their high homology and overlapping target messenger RNAs (mRNAs), Pum1 promotes differentiation while Pum2 promotes self-renewal in ESCs. Pum1 and Pum2 achieve these two complementary aspects of pluripotency by forming a negative interregulatory feedback loop that directly regulates at least 1,486 mRNAs. Pum1 and Pum2 regulate target mRNAs not only by repressing translation, but also by promoting translation and enhancing or reducing mRNA stability of different target mRNAs. Together, these findings reveal distinct roles of individual mammalian Pum proteins in ESCs and their essential functions in ESC pluripotency and embryogenesis.

Katherine Uyhazi and renowned gene therapy pioneer Jean Bennett share their perspective on the 2020 Nobel Prize in Chemistry awarded to Emmanuelle Charpentier and Jennifer Doudna for their discovery of the CRISPR/Cas9 genetic scissors that have revolutionized genome editing.

SUMMARYGlaucoma is the leading cause of irreversible blindness worldwide and is characterized by the death of retinal ganglion cells. Reduction of intraocular pressure (IOP) is the only therapeutic mechanism available to slow disease progression. However, glaucoma can continue to progress despite normalization of IOP. New treatments are needed to reduce vision loss and improve outcomes for patients who have exhausted existing therapeutic avenues. Recent studies have implicated neuroinflammation in the pathogenesis of neurodegenerative diseases of both the retina and the brain, including glaucoma and Parkinson’s disease. Pro-inflammatory A1 astrocytes contribute to neuronal cell death in multiple disease processes and have been targeted therapeutically in mouse models of Parkinson’s disease. Microglial release of pro-inflammatory cytokines C1q, IL-1α, and TNF-α is sufficient to drive the formation of A1 astrocytes. The role of A1 astrocytes in glaucoma pathogenesis has not been explored. Using a mouse model of glaucoma, we demonstrated that IOP elevation was sufficient to trigger production of C1q, IL-1α, and TNF-α by infiltrating macrophages followed by resident microglia. These three cytokines drove the formation of A1 astrocytes in the retina. Furthermore, cytokine production and A1 astrocyte transformation persisted following IOP normalization. Ablation of this pathway, by either genetic deletions of C1q, IL-1α, and TNF-α, or treatment with glucagon-like peptide-1 receptor agonist NLY01, reduced A1 astrocyte transformation and RGC death. Together, these results highlight a new neuroinflammatory mechanism behind glaucomatous neurodegeneration that can be therapeutically targeted by NLY01 administration.

SUMMARY Glaucoma is the leading cause of irreversible blindness and is characterized by the death of retinal ganglion cells (RGCs). Recent studies have implicated pro-inflammatory microglia, macrophages, and A1 astrocytes in the pathogenesis of neurodegenerative diseases. The role of pro-inflammatory, neurotoxic A1 astrocytes in glaucoma is just beginning to be explored. Using a mouse model of glaucoma, we demonstrate that ocular hypertension is sufficient to trigger production of C1q, interleukin-1α (IL-1α), and tumor necrosis factor α (TNF-α), three cytokines necessary and sufficient to drive the formation of A1 astrocytes. Upregulation of these cytokines occurs first in CD11b+ CD11c+ cells followed by CD11b+ CD11c− cells. Ablation of this pathway, by either genetic deletions of C1qa, IL-1α, and TNF-α, or treatment with glucagon-like peptide-1 receptor agonist NLY01, reduces A1 astrocyte transformation and RGC death. Together, these results highlight a neuroinflammatory mechanism of glaucomatous neurodegeneration that can be therapeutically targeted by NLY01 administration., Graphical Abstract, In Brief Sterling et al. show that in response to ocular hypertension, CD11b+ CD11c+ cells contribute to early retinal inflammation and astrogliosis in a mouse model of glaucoma. Ablation of this inflammatory pathway, via genetic deletion or administration of the GLP-1R agonist NLY01, prevents astrogliosis and retinal ganglion cell death.

Purpose To determine the therapeutic window for gene augmentation for Leber congenital amaurosis (LCA) associated with mutations in LCA5. Methods Five patients (ages 6-31) with LCA and biallelic LCA5 mutations underwent an ophthalmic examination including optical coherence tomography (SD-OCT), full-field stimulus testing (FST), and pupillometry. The time course of photoreceptor degeneration in the Lca5gt/gt mouse model and the efficacy of subretinal gene augmentation therapy with AAV8-hLCA5 delivered at postnatal day 5 (P5) (early, n = 11 eyes), P15 (mid, n = 14), and P30 (late, n = 13) were assessed using SD-OCT, histologic study, electroretinography (ERG), and pupillometry. Comparisons were made with the human disease. Results Patients with LCA5-LCA showed a maculopathy with detectable outer nuclear layer (ONL) in the pericentral retina and at least 4 log units of dark-adapted sensitivity loss. The Lca5gt/gt mouse has a similarly severe and rapid photoreceptor degeneration. The ONL became progressively thinner and was undetectable by P60. Rod- and cone-mediated ERGs were severely reduced in amplitudes at P30 and became nondetectable by P60. Subretinal AAV8-hLCA5 administered to Lca5gt/gt mice at P5 and P15, but not at P30, resulted in structural and functional rescue. Conclusions LCA5-LCA is a particularly severe form of LCA that was recapitulated in the Lca5gt/gt mouse. Gene augmentation resulted in structural and functional rescue in the Lca5gt/gt mouse if delivered before P30. Retained photoreceptors were visible within the central retina in all patients with LCA5-LCA, at a level equivalent to that observed in rescued Lca5gt/gt mice, suggesting a window of opportunity for the treatment of patients with LCA5-LCA.

To describe early structural and functional retinal changes in a patient with Cohen syndrome.A 13-month-old Caucasian girl of Irish and Spanish ancestry was noted to have micrognathia and laryngomalacia at birth, which prompted a genetic evaluation that revealed biallelic deletions in COH1 (VPS13B) (a maternally inherited 60-kb deletion involving exons 26-32 and a paternally inherited 3.5-kb deletion within exon 17) consistent with Cohen syndrome. She underwent a complete ophthalmic examination, full-field flash electroretinography and retinal imaging with spectral domain optical coherence tomography.Central vision was central, steady, and maintained. There was bilateral myopic astigmatic refractive error. Fundus exam was notable for dark foveolar pigmentation, but no obvious abnormalities of either eye. Spectral domain optical coherence tomography cross sections through the fovea revealed a normal appearing photoreceptor outer nuclear layer but loss of the interdigitation signal between the photoreceptor outer segments and the apical retinal pigment epithelium. Retinoschisis involving the inner nuclear layer of both eyes and possible ganglion cell layer thinning were also noted. There was a detectable electroretinogram with similarly reduced amplitudes of rod- (white, 0.01 cd.s.mPhotoreceptor outer segment abnormalities and retinoschisis may represent the earliest structural retinal change detected by spectral domain optical coherence tomography in patients with Cohen syndrome, suggesting a complex pathophysiology with primary involvement of the photoreceptor cilium and disorganization of the structural integrity of the inner retina.

Gene regulation in embryonic stem cells (ESCs) has been extensively studied at the epigenetic-transcriptional levels, but not at the post-transcriptional levels. Pumilio (Pum) proteins are among the few known translational regulators required for stem cell maintenance in invertebrates and plants. Here we report the essential function of two murine Pum proteins, Pum1 and Pum2, in ESCs and early embryogenesis. Pum1/2 double mutants are developmentally delayed at the morula stage and lethal by embryonic day 8.5 (e8.5). Correspondingly, Pum1/2 double mutant ESCs display severely reduced self-renewal and differentiation, revealing the combined function of Pum1 and Pum2 in ESC pluripotency. Remarkably, Pum1-deficient ESCs show increased expression of pluripotency genes but not differentiation genes, indicating that Pum1 mainly promote differentiation; whereas Pum2-deficient ESCs show decreased expression of pluripotency genes and accelerated differentiation, indicating that Pum2 promotes self-renewal. Thus, Pum1 and Pum2 each uniquely contributes to one of the two complementary aspects of pluripotency. Furthermore, we show that Pum1 and Pum2 achieve ESC functions by forming a negative auto- and inter-regulatory feedback loop that directly regulates at least 1,486 mRNAs. Pum1 and Pum2 regulate target mRNAs not only by repressing translation as expected but also by promoting translation and enhancing or reducing mRNA stability of different target mRNAs. Together, these findings reveal the distinct roles of individual mammalian Pum proteins in ESCs and their collectively essential functions in ESC pluripotency and embryogenesis. Moreover, they demonstrate three novel modes of regulation of Pum proteins towards target mRNAs.SIGNIFICANCE STATEMENTThis report demonstrates the essential functions of mammalian Pumilio (Pum) proteins for embryonic stem cells (ESCs) pluripotency and embryogenesis. Moreover, it reveals the contrasting but complementary function of individual Pum proteins in regulating distinct aspects of ESC pluripotency, despite their largely overlapping expression and extremely high homology. Furthermore, it unravels a complex regulatory network in which Pum1 and Pum2 form a negative auto- and inter-regulatory feedback loop that regulates 1,486 mRNAs not only by translational repression as expected but also by promoting translation and enhancing or reducing stability of different target mRNAs, which reveals novel modes of post-transcriptional regulation mediated by Pum.

Inherited retinal degenerations are a common cause of untreatable blindness worldwide, with retinitis pigmentosa and cone dystrophy affecting approximately 1 in 3500 and 1 in 10,000 individuals, respectively. A major limitation to the development of effective therapies is the lack of availability of animal models that fully replicate the human condition. Particularly for cone disorders, rodent, canine, and feline models with no true macula have substantive limitations. By contrast, the cone-rich macula of a nonhuman primate (NHP) closely mirrors that of the human retina. Consequently, well-defined NHP models of heritable retinal diseases, particularly cone disorders that are predictive of human conditions, are necessary to more efficiently advance new therapies for patients. We have identified 4 related NHPs at the California National Primate Research Center with visual impairment and findings from clinical ophthalmic examination, advanced retinal imaging, and electrophysiology consistent with achromatopsia. Genetic sequencing confirmed a homozygous R565Q missense mutation in the catalytic domain of PDE6C, a cone-specific phototransduction enzyme associated with achromatopsia in humans. Biochemical studies demonstrate that the mutant mRNA is translated into a stable protein that displays normal cellular localization but is unable to hydrolyze cyclic GMP (cGMP). This NHP model of a cone disorder will not only serve as a therapeutic testing ground for achromatopsia gene replacement, but also for optimization of gene editing in the macula and of cone cell replacement in general.

PURPOSE: To assess the potential ocular toxicity of a combined BRAF inhibition (BRAFi) + MEK inhibition (MEKi) + hydroxychloroquine (HCQ) regime used to treat metastatic BRAF mutant melanoma. METHODS: Patients with stage IV metastatic melanoma and BRAF V600E mutations (n = 11, 31–68 years of age) were included. Treatment was with oral dabrafenib, 150 mg bid, trametinib, 2 mg/day, and HCQ, 400 mg to 600 mg bid. An ophthalmic examination, spectral domain optical coherence tomography, near-infrared and short-wavelength fundus autofluorescence, and static perimetry were performed at baseline, 1 month, and q/6 months after treatment. RESULTS: There were no clinically significant ocular events; there was no ocular inflammation. The only medication-related change was a separation of the photoreceptor outer segment tip from the apical retinal pigment epithelium that could be traced from the fovea to the perifoveal retina noted in 9/11 (82%) of the patients. There were no changes in retinal pigment epithelium melanization or lipofuscin content by near-infrared fundus autofluorescence and short-wavelength fundus autofluorescence, respectively. There were no inner retinal or outer nuclear layer changes. Visual acuities and sensitivities were unchanged. CONCLUSION: BRAFi (trametinib) + MEKi (dabrafenib) + HCQ causes very frequent, subclinical separation of the photoreceptor outer segment from the apical retinal pigment epithelium without inner retinal changes or signs of inflammation. The changes suggest interference with the maintenance of the outer retinal barrier and/or phagocytic/pump functions of the retinal pigment epithelium by effective MEK inhibition.

Importance Novel oral anticoagulation and antiplatelet therapies have become a mainstay of treatment for thromboembolic disease. However, the safety profile of these medications has not been completely characterized. Objective To determine the risk of developing intraocular hemorrhages with novel oral antithrombotic therapy compared with that of traditional antithrombotic agents. Design, Setting, and Participants In this retrospective cohort study, a large national insurance claims database was used to generate 2 parallel analyses. All patients with incident use of dabigatran etexilate or rivaroxaban between January 1, 2010, and September 30, 2015, were compared with patients with incident use of warfarin sodium. Similarly, patients with new use of prasugrel hydrochloride were compared with those with new use of clopidogrel bisulfate. Both analyses required the patient to be in the insurance plan for at least 24 months prior to initiation of therapy and excluded patients with any previous diagnosis of intraocular hemorrhages or any prescription for the comparator medications. Furthermore, the antiplatelet analysis required a diagnosis of acute coronary syndrome or a myocardial infarction within 60 days of initiation of pharmacologic therapy. The anticoagulant analysis excluded patients with end-stage renal disease, renal transplants, and those with heart valve disease. Main Outcomes and Measures Incident intraocular hemorrhages at 90 and 365 days. Multivariate Cox proportional hazards regression models were used to compare the hazard ratio (HR) of developing an intraocular hemorrhage in individuals taking novel agents compared with those taking traditional medications. Results A total of 146 137 patients taking warfarin (76 714 women and 69 423 men; mean [SD] age, 69.8 [11.8] years) were compared with 64 291 patients taking dabigatran or rivaroxaban (31 576 women and 32 715 men; mean [SD] age, 67.6 [11.7] years). Cox proportional hazards regression revealed a decreased hazard for developing an intraocular hemorrhage with dabigatran or rivaroxaban at 365 days (HR, 0.75; 95% CI, 0.58-0.97;P = .03), but not at 90 days (HR, 0.73; 95% CI, 0.22-2.63;P = .13). A total of 103 796 patients taking clopidogrel (37 578 women and 66 218 men; mean [SD] age, 68.0 [11.3] years) were compared with 8386 patients taking prasugrel (1988 women and 6380 men; mean [SD] age, 61.0 [9.6] years) and no increased hazard for developing an intraocular hemorrhage with prasugrel was seen at 90 days (HR, 0.75; 95% CI, 0.29-1.92;P = .55) or 365 days (HR, 1.19; 95% CI, 0.69-2.04;P = .53). Conclusions and Relevance These results suggest a decreased risk of intraocular hemorrhage associated with novel direct thrombin inhibitors and direct factor Xa inhibitors, but no difference for P2Y12inhibitors compared with traditional vitamin K anticoagulation and antiplatelet therapy, respectively.

The authors describe a case of presumed endogenous fungal endophthalmitis in an immunocompetent pediatric patient with acute lymphoblastic leukemia. A 15-year-old boy with a history of high-risk B-cell acute lymphoblastic leukemia status post-chemotherapy presented with acute changes in vision in his left eye. Fundus examination revealed a white bi-lobed chorioretinal lesion with overlying vitritis and associated subretinal fluid. Magnetic resonance imaging of the brain revealed small ring-enhancing lesions in the right parietal and left occipital lobes. Blood, cerebrospinal fluid, aqueous, and vitreous cultures were all negative. Bone marrow and vitreous cytology were negative for malignant cells. The patient was treated for presumed fungal endophthalmitis with systemic and intravitreal voriconazole, followed by pars plana vitrectomy with intravitreal voriconazole and amphotericin B injections. The chorioretinal lesion resolved and visual acuity recovered to 20/20. Chorioretinal infiltrates in a patient with leukemia may require treatment even in the absence of a definitive diagnostic test result. Intervention should be guided by risk analysis and clinical judgment. [ J Pediatr Ophthalmol Strabismus. 2017;54:e42–e46.]

Primary open-angle glaucoma (POAG) is a genetically, physiologically, and phenotypically complex neurodegenerative disorder. This study addressed the expanding collection of genes associated with POAG, referred to as the "POAGome." We used bioinformatics tools to perform an extensive, systematic literature search and compiled 542 genes with confirmed associations with POAG and its related phenotypes (normal tension glaucoma, ocular hypertension, juvenile open-angle glaucoma, and primary congenital glaucoma). The genes were classified according to their associated ocular tissues and phenotypes, and functional annotation and pathway analyses were subsequently performed. Our study reveals that no single molecular pathway can encompass the pathophysiology of POAG. The analyses suggested that inflammation and senescence may play pivotal roles in both the development and perpetuation of the retinal ganglion cell degeneration seen in POAG. The TGF-β signaling pathway was repeatedly implicated in our analyses, suggesting that it may be an important contributor to the manifestation of POAG in the anterior and posterior segments of the globe. We propose a molecular model of POAG revolving around TGF-β signaling, which incorporates the roles of inflammation and senescence in this disease. Finally, we highlight emerging molecular therapies that show promise for treating POAG.

Purpose To describe the retinal phenotype of pediatric patients with mutations in the retinol dehydrogenase 12 (RDH12) gene. Methods Twenty-one patients from 14 families (ages 2-17 years) with RDH12-associated inherited retinal degeneration (RDH12-IRD) underwent a complete ophthalmic exam and imaging with spectral domain optical coherence tomography (SD-OCT) and near infrared and short-wavelength fundus autofluorescence. Visual field extent was measured with Goldmann kinetic perimetry, visual thresholds with dark-adapted static perimetry or with dark-adapted chromatic full-field stimulus testing (FST) and transient pupillometry. Results Visual acuity ranged from 20/40 to light perception. There was parafoveal depigmentation or atrophic maculopathies accompanied by midperipheral intraretinal pigment migration. SD-OCT revealed foveal thinning in all patients and detectable but thinned outer nuclear layer (ONL) at greater eccentricities from the fovea. Photoreceptor outer segment (POS) signals were only detectable in small pockets within the central retina. Measurable kinetic visual fields were limited to small (

We previously demonstrated that the Kaposi's sarcoma-associated herpesvirus polyadenylated nuclear RNA contains a 79-nt cis-acting element, the ENE, which allows intronless polyadenylated transcripts to accumulate to high nuclear levels by protecting them from rapid degradation. We proposed a model based on the predicted structure of the ENE in which a U-rich internal loop hybridizes with the 3′-polyadenylate (polyA) tail to sequester it from exonucleolytic attack. We have tested this model by mutational analysis of the ENE. Point mutations in the predicted U-rich internal loop and in the flanking stems abolish the ENE's ability to ( i ) interact with the polyA tail, ( ii ) inhibit deadenylation in vitro , and ( iii ) stabilize transcripts in vivo . In all but one case, compensatory mutations in the flanking stems restore ENE activities, demonstrating the importance of these stems and uncovering a unique role for the loop-proximal G-C base pair in the lower stem. Increasing the U content of the U-rich internal loop surprisingly decreases stability in vivo but does not affect deadenylation in vitro , comparable to the effects of deleting certain “unstructured” regions of the ENE. Taken together, our data support the formation of the proposed ENE secondary structure in vivo and argue that the specific ENE structure inhibits rapid RNA decay in cis by engaging in a limited set of base-pairing interactions with the polyA tail.

SummaryDuring spermatogenesis, germ cells initially expand exponentially through mitoses. A majority of these cells are then eliminated through p53-mediated apoptosis to maintain germline homeostasis [1–4]. However, the activity of p53 must be precisely modulated, especially suppressed in postmitotic spermatogenic cells, to guarantee robustness of spermatogenesis. Currently, how the suppression is achieved is not understood. Here, we show that Pumilio 1, a posttranscriptional regulator, binds to mRNAs representing 1,527 genes, with significant enrichment for mRNAs involved in pathways regulating p53, cell cycle, and MAPK signaling. In particular, eight mRNAs encoding activators of p53 are repressed by Pumilio 1. Deleting Pumilio 1 results in strong activation of p53 and apoptosis mostly in spermatocytes, which disrupts sperm production and fertility. Removing p53 reduces apoptosis and rescues testicular hypotrophy in Pumilio 1 null mice. These results indicate that key components of the p53 pathway are coordinately regulated by Pumilio 1 at the posttranscriptional level, which may exemplify an RNA operon.