February 2019

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Singh G, Ismail AM, Lee JY, Ramke M, Lee JS, Dyer DW, Seto D, Rajaiya J, Chodosh J. Divergent Evolution of E1A CR3 in Human Adenovirus Species D. Viruses 2019;11(2)Abstract
Adenovirus E1A is the first viral protein expressed during infection. E1A controls critical aspects of downstream viral gene expression and cell cycle deregulation, and its function is thought to be highly conserved among adenoviruses. Various bioinformatics analyses of E1A from 38 human adenoviruses of species D (HAdV-D), including likelihood clade model partitioning, provided highly significant evidence of divergence of HAdV-Ds into two distinct groups for the conserved region 3 (CR3), present only in the E1A 13S isoform. This variance within E1A 13S of HAdV-Ds was not found in any other human adenovirus (HAdV) species. By protein sequence and structural analysis, the zinc finger motif of E1A CR3, previously shown as critical for transcriptional activation, showed the greatest differences. Subsequent codon usage bias analysis revealed substantial divergence in E1A 13S between the two groups of HAdV-Ds, suggesting that these two sub-groups of HAdV-D evolved under different cellular conditions. Hence, HAdV-D E1A embodies a previously unappreciated evolutionary divergence among HAdVs.
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Thorne JE, Sugar EA, Holbrook JT, Burke AE, Altaweel MM, Vitale AT, Acharya NR, Kempen JH, Jabs DA, Jabs DA. Periocular Triamcinolone vs. Intravitreal Triamcinolone vs. Intravitreal Dexamethasone Implant for the Treatment of Uveitic Macular Edema: The PeriOcular vs. INTravitreal corticosteroids for uveitic macular edema (POINT) Trial. Ophthalmology 2019;126(2):283-295.Abstract
PURPOSE: To evaluate the comparative effectiveness of 3 regional corticosteroid injections for uveitic macular edema (ME): periocular triamcinolone acetonide (PTA), intravitreal triamcinolone acetonide (ITA), and the intravitreal dexamethasone implant (IDI). DESIGN: Multicenter, randomized clinical trial. PARTICIPANTS: Patients with uveitic ME. METHODS: Patients were randomized 1:1:1 to receive 1 of the 3 therapies. Patients with bilateral ME were assigned the same treatment for both eyes. MAIN OUTCOME MEASURES: The primary outcome was the proportion of baseline (PropBL) central subfield thickness (CST) at 8 weeks (CST at 8 weeks/CST at baseline) assessed with OCT by masked readers. Secondary outcomes included ≥20% improvement and resolution of ME, best-corrected visual acuity (BCVA), and intraocular pressure (IOP) events over 24 weeks. RESULTS: All treatment groups demonstrated improved CST during follow-up. At 8 weeks, each group had clinically meaningful reductions in CST relative to baseline (PropBL: 0.77, 0.61, and 0.54, respectively, which translates to reductions of 23%, 39%, and 46% for PTA, ITA, and IDI, respectively). Intravitreal triamcinolone acetonide (PropBL ITA/PropBL PTA, hazard ratio [HR], 0.79; 99.87% confidence interval [CI], 0.65-0.96) and IDI (PropBL IDI/PropBL PTA, HR, 0.69; 99.87% CI, 0.56-0.86) had larger reductions in CST than PTA (P < 0.0001). Intravitreal dexamethasone implant was noninferior to ITA at 8 weeks (PropBL IDI/PropBL ITA, HR, 0.88; 99.87% CI, 0.71-1.08). Both ITA and IDI treatments also were superior to PTA treatment in improving and resolving uveitic ME. All treatment groups demonstrated BCVA improvement throughout follow-up. Both ITA and IDI groups had improvements in BCVA that was 5 letters greater than in the PTA group at 8 weeks (P < 0.004). The risk of having IOP ≥24 mmHg was higher in the intravitreal treatment groups compared with the periocular group (HR, 1.83; 95% CI, 0.91-3.65 and HR, 2.52; 95% CI, 1.29-4.91 for ITA and IDI, respectively); however, there was no significant difference between the 2 intravitreal treatment groups. CONCLUSIONS: Intravitreal triamcinolone acetonide and the IDI were superior to PTA for treating uveitic ME with modest increases in the risk of IOP elevation. This risk did not differ significantly between intravitreal treatments.
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Wang Y, Liu C-H, Ji T, Mehta M, Wang W, Marino E, Chen J, Kohane DS. Intravenous treatment of choroidal neovascularization by photo-targeted nanoparticles. Nat Commun 2019;10(1):804.Abstract
Choroidal neovascularization (CNV) is the major cause of vision loss in wet age-related macular degeneration (AMD). Current therapies require repeated intravitreal injections, which are painful and can cause infection, bleeding, and retinal detachment. Here we develop nanoparticles (NP-[CPP]) that can be administered intravenously and allow local drug delivery to the diseased choroid via light-triggered targeting. NP-[CPP] is formed by PEG-PLA chains modified with a cell penetrating peptide (CPP). Attachment of a DEACM photocleavable group to the CPP inhibits cellular uptake of NP-[CPP]. Irradiation with blue light cleaves DEACM from the CPP, allowing the CPP to migrate from the NP core to the surface, rendering it active. In mice with laser-induced CNV, intravenous injection of NP-[CPP] coupled to irradiation of the eye allows NP accumulation in the neovascular lesions. When loaded with doxorubicin, irradiated NP-[CPP] significantly reduces neovascular lesion size. We propose a strategy for non-invasive treatment of CNV and enhanced drug accumulation specifically in diseased areas of the eye.
Woodward AM, Lehoux S, Mantelli F, Di Zazzo A, Brockhausen I, Bonini S, Argüeso P. Inflammatory Stress Causes N-Glycan Processing Deficiency in Ocular Autoimmune Disease. Am J Pathol 2019;189(2):283-294.Abstract
High levels of proinflammatory cytokines have been associated with a loss of tissue function in ocular autoimmune diseases, but the basis for this relationship remains poorly understood. Here we investigate a new role for tumor necrosis factor α in promoting N-glycan-processing deficiency at the surface of the eye through inhibition of N-acetylglucosaminyltransferase expression in the Golgi. Using mass spectrometry, complex-type biantennary oligosaccharides were identified as major N-glycan structures in differentiated human corneal epithelial cells. Remarkably, significant differences were detected between the efficacies of cytokines in regulating the expression of glycogenes involved in the biosynthesis of N-glycans. Tumor necrosis factor α but not IL-1β had a profound effect in suppressing the expression of enzymes involved in the Golgi branching pathway, including N-acetylglucosaminyltransferases 1 and 2, which are required for the formation of biantennary structures. This decrease in gene expression was correlated with a reduction in enzymatic activity and impaired N-glycan branching. Moreover, patients with ocular mucous membrane pemphigoid were characterized by marginal N-acetylglucosaminyltransferase expression and decreased N-glycan branching in the conjunctiva. Together, these data indicate that proinflammatory cytokines differentially influence the expression of N-glycan-processing enzymes in the Golgi and set the stage for future studies to explore the pathophysiology of ocular autoimmune diseases.

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