Ophthalmology Commons^™

Gene-Agnostic Therapeutic Strategies For Inherited Retinal Diseases: Neuroprotection And Immunomodulation, Lucas W. Rowe, S. Patricia Becerra, Robert E. Maclaren, Robert L. Avery, Charles C. Wykoff, Allen C. Ho, Carl D. Regillo, Dean Eliott, Andrew Osborne, Katie M. Binley, Thomas A. Ciulla

Wills Eye Hospital Papers

Background/Objectives: Inherited retinal diseases (IRDs) represent a genetically heterogeneous group of disorders caused by mutations in over 280 genes with more than 3100 identified variants. While gene-specific replacement therapies have achieved landmark success with voretigene neparvovec (Luxturna) for biallelic RPE65-associated retinal dystrophy, developing individual therapies for each genetic subtype remains impractical. This review examines gene-agnostic therapeutic approaches utilizing neuroprotection and immunomodulation that target common pathophysiological mechanisms shared across multiple IRD genotypes. Methods: We reviewed the literature on neuroprotective and immunomodulatory gene therapy strategies for IRDs, focusing on neurotrophic factors and complement system modulation. Results: Neuroprotective approaches delivering neurotrophic factors—including pigment …

Apostel-R Recommendations For Reporting Retinal Optical Coherence Tomography Studies In Rodents, Frederike Cosima Oertel, Delia Cabrera Debuc, Peter A. Calabresi, Mei Chen, Christian Cordano, Michael Dietrich, Nicolas Feltgen, Oliver Gramlich, Ari J. Green, Janos Groh, Su-Chun Huang, Benjamin Knier, Thomas Korn, Letizia Leocani, Anat Loewenstein, Christian Van Oterendorp, Tunde Peto, Sven Schippling, Leopold Schmetterer, Steffen Schmitz-Valckenberg, Mathias W. Seeliger, Kenneth S. Shindler, Joel Schuman, Mustafa Sindi, Adnan Tufail, Jui-Kai Wang, Sebastian Wolf, Yuyi You, Martin Zinkernagel, Wolf Lagrèze, Philipp Albrecht

Department of Medicine Faculty Papers

BACKGROUND AND OBJECTIVES: Retinal optical coherence tomography (OCT) in rodent models has been used to longitudinally image retinal changes, to define end points for more costly or time-consuming experiments, and to better understand the pathophysiology underlying OCT findings in human diseases. No standardization of rodent OCT reporting currently exists. Here, we aim to establish consensus recommendation for reporting results from retinal OCT studies in rodents.

METHODS: Initial recommendations were developed based on the APOSTEL criteria for quantitative OCT reporting in humans by a core team. Using a modified Delphi process, an expert panel of rodent OCT researchers (N = 31) …

Lamina Cribrosa Microstructure In Nonhuman Primates With Naturally Occurring Peripapillary Retinal Nerve Fiber Layer Thinning, Palaiologos Alexopoulos, Arthur G Fernandes, Zeinab Ghassabi, Ronald Zambrano, Anse Vellappally, Eitan Shemuelian, Tingfang Lee, Jiyuan Hu, Armando Burgos-Rodriguez, Melween I Martinez, Joel S. Schuman, Amanda D Melin, James P Higham, John Danias, Gadi Wollstein

Wills Eye Hospital Papers

PURPOSE: The lamina cribrosa (LC) is hypothesized to be the site of initial axonal damage in glaucoma with the circumpapillary retinal nerve fiber layer thickness (RNFL-T) widely used as a standard metric for quantifying the glaucomatous damage. The purpose of this study was to determine in vivo, 3-dimensional (3D) differences in the microstructure of the LC in eyes of nonhuman primates (NHPs) with naturally occurring glaucoma.

METHODS: Spectral-domain optical coherence tomography (OCT) scans (Leica, Chicago, IL, USA) of the optic nerve head were acquired from a colony of 50 adult rhesus monkeys suspected of having high prevalence of glaucoma. The …

Immunoregulatory Properties Of Immune Cells That Associate With The Lens Capsule Surface During Acute And Resolution Phases Of Experimental Autoimmune Uveitis, Phuong M. Le, Mary J. Mattapallil, Rachel R. Caspi, Mary Ann Stepp, A. Sue Menko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Inflammation in the eye is tightly regulated to prevent vision impairment and irreversible blindness. Emerging evidence shows that immune cells are specifically recruited to the lens capsule in response to autoimmune uveitis, yet the potential that they have a role in regulating this inflammatory disease remained unexplored. Here, an immunolocalization approach combined with high-resolution confocal microscopy was used to investigate whether the immune cells that become stably associated with the lens capsule in the eyes of C57BL/6J mice with experimental autoimmune uveitis (EAU) have an immunoregulatory phenotype. These studies revealed that during the acute phase of uveitis, at day 18 …

High Clinical Exome Sequencing Diagnostic Rates And Novel Phenotypic Expansions For Nonisolated Microphthalmia, Anophthalmia, And Coloboma, Bhavana Kunisetty, Bailey A Martin-Giacalone, Xiaonan Zhao, Pamela N Luna, Brian P Brooks, Robert B Hufnagel, Chad A Shaw, Jill A Rosenfeld, A J Agopian, Philip J Lupo, Daryl A Scott

Faculty, Staff and Student Publications

PURPOSE: A molecular diagnosis is only made in a subset of individuals with nonisolated microphthalmia, anophthalmia, and coloboma (MAC). This may be due to underutilization of clinical (whole) exome sequencing (cES) and an incomplete understanding of the genes that cause MAC. The purpose of this study is to determine the efficacy of cES in cases of nonisolated MAC and to identify new MAC phenotypic expansions.

METHODS: We determined the efficacy of cES in 189 individuals with nonisolated MAC. We then used cES data, a validated machine learning algorithm, and previously published expression data, case reports, and animal models to determine …

The Atoh1-Cre Knock-In Allele Ectopically Labels A Subpopulation Of Amacrine Cells And Bipolar Cells In Mouse Retina, Sih-Rong Wu, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

The retina has diverse neuronal cell types derived from a common pool of retinal progenitors. Many molecular drivers, mostly transcription factors, have been identified to promote different cell fates. In Drosophila, atonal is required for specifying photoreceptors. In mice, there are two closely related atonal homologs, Atoh1 and Atoh7. While Atoh7 is known to promote the genesis of retinal ganglion cells, there is no study on the function of Atoh1 in retinal development. Here, we crossed Atoh1^Cre/+ mice to mice carrying a Cre-dependent TdTomato reporter to track potential Atoh1-lineage neurons in retinas. We characterized a heterogeneous …

Nlrp3 Selectively Drives Il-1Β Secretion By Pseudomonas Aeruginosa Infected Neutrophils And Regulates Corneal Disease Severity, Martin S Minns, Karl Liboro, Tatiane S Lima, Serena Abbondante, Brandon A Miller, Michaela E Marshall, Jolynn Tran Chau, Alicia Roistacher, Arne Rietsch, George R Dubyak, Eric Pearlman

Faculty, Staff and Student Publications

Macrophages infected with Gram-negative bacteria expressing Type III secretion system (T3SS) activate the NLRC4 inflammasome, resulting in Gasdermin D (GSDMD)-dependent, but GSDME independent IL-1β secretion and pyroptosis. Here we examine inflammasome signaling in neutrophils infected with Pseudomonas aeruginosa strain PAO1 that expresses the T3SS effectors ExoS and ExoT. IL-1β secretion by neutrophils requires the T3SS needle and translocon proteins and GSDMD. In macrophages, PAO1 and mutants lacking ExoS and ExoT (ΔexoST) require NLRC4 for IL-1β secretion. While IL-1β release from ΔexoST infected neutrophils is also NLRC4-dependent, infection with PAO1 is instead NLRP3-dependent and driven by the ADP ribosyl transferase activity …

Demodex Blepharitis: A Comprehensive Review Of The Disease, Current Management, And Emerging Therapies, Michelle K. Rhee, Elizabeth Yeu, Melissa Barnett, Christopher J. Rapuano, Deepinder K Dhaliwal, Kelly K. Nichols, Paul Karpecki, Francis S. Mah, Arthur Chan, James Mun, Ian Benjamin Gaddie

Wills Eye Hospital Papers

Demodex blepharitis is a common disease of the eyelid, affecting approximately 25 million Americans. This article reviews what is known about the mechanisms and impact of Demodex blepharitis, risk factors, signs and symptoms, diagnostic techniques, current management options, and emerging treatments. Demodex mites contribute to blepharitis in several ways: direct mechanical damage, as a vector for bacteria, and by inducing hypersensitivity and inflammation. Risk factors for Demodex blepharitis include increasing age, rosacea, and diabetes. The costs, symptom burden, and psychosocial effects of Demodex blepharitis are considerable. The presence of collarettes is pathognomonic for Demodex blepharitis. Redness, dryness, discomfort, foreign body …

Upregulation Of Epac1 Promotes Pericyte Loss By Inducing Mitochondrial Fission, Reactive Oxygen Species Production, And Apoptosis, Wenli Yang, Fan Xia, Fang Mei, Shuizhen Shi, William G Robichaux, Wei Lin, Wenbo Zhang, Hua Liu, Xiaodong Cheng

The Brown Foundation: Institute of Molecular Medicine

PURPOSE: The pathogenic mechanisms behind the development of ischemic retinopathy are complex and poorly understood. This study investigates the involvement of exchange protein directly activated by cAMP (Epac)1 signaling in pericyte injury during ischemic retinopathy, including diabetic retinopathy, a disease that threatens vision.

METHODS: Mouse models of retinal ischemia-reperfusion injury and type 1 diabetes induced by streptozotocin were used to investigate the pathogenesis of these diseases. The roles of Epac1 signaling in the pathogenesis of ischemic retinopathy were determined by an Epac1 knockout mouse model. The cellular and molecular mechanisms of Epac1-mediated pericyte dysfunction in response to high glucose were …

Soy Isoflavone Reduces Lps-Induced Acute Lung Injury Via Increasing Aquaporin 1 And Aquaporin 5 In Rats, Yuan-Hao Lee, W Wade Kothmann, Ya-Ping Lin, Alice Z Chuang, Jeffrey S Diamond, John O'Brien

Faculty, Staff and Student Publications

Synaptic plasticity is a fundamental feature of the CNS that controls the magnitude of signal transmission between communicating cells. Many electrical synapses exhibit substantial plasticity that modulates the degree of coupling within groups of neurons, alters the fidelity of signal transmission, or even reconfigures functional circuits. In several known examples, such plasticity depends on calcium and is associated with neuronal activity. Calcium-driven signaling is known to promote potentiation of electrical synapses in fish Mauthner cells, mammalian retinal AII amacrine cells, and inferior olive neurons, and to promote depression in thalamic reticular neurons. To measure local calcium dynamics

Preparation And Immunofluorescence Staining Of Bundles And Single Fiber Cells From The Cortex And Nucleus Of The Eye Lens, Michael P Vu, Catherine Cheng

Faculty, Staff and Student Publications

The lens is a transparent and ellipsoid organ in the anterior chamber of the eye that changes shape to finely focus light onto the retina to form a clear image. The bulk of this tissue comprises specialized, differentiated fiber cells that have a hexagonal cross section and extend from the anterior to the posterior poles of the lens. These long and skinny cells are tightly opposed to neighboring cells and have complex interdigitations along the length of the cell. The specialized interlocking structures are required for normal biomechanical properties of the lens and have been extensively described using electron microscopy …

Effects Of Different Spectrum Of Leds On Retinal Degeneration Through Regulating Endoplasmic Reticulum Stress, Wenyi Chen, Rong Lin, Kunhong Xiao, Kun Yuan, Zhongjiang Chen, Yan Huang

Faculty, Staff and Student Publications

PURPOSE: To evaluate the impact of full-spectrum light-emitting diodes (LEDs) on albino guinea pigs' retina and investigate the roles of short-wavelength opsin (S-opsin) and endoplasmic reticulum (ER) stress in light-induced retinal degeneration (LIRD).

METHODS: Three-week-old albino guinea pigs (n = 30) were distributed into five groups under 12/12 light/dark cycles with indoor natural light (NC; 300-500 lux, n = 6), full-spectrum LEDs (FL; 300 lux, n = 6; 3000 lux, n = 6), and commercial cold-white LEDs (CL; 300 lux, n = 6; 3000 lux, n = 6) and raised for 28 days. Hematoxylin and eosin staining and transmission electron …

Extracellular-Vesicle-Based Therapeutics In Neuro-Ophthalmic Disorders, Hamed Massoumi, Sohil Amin, Mohammad Soleimani, Bita Momenaei, Mohammad Javad Ashraf, Victor H Guaiquil, Peiman Hematti, Mark I Rosenblatt, Ali R Djalilian, Elmira Jalilian

Wills Eye Hospital Papers

Extracellular vesicles (EVs) have been recognized as promising candidates for developing novel therapeutics for a wide range of pathologies, including ocular disorders, due to their ability to deliver a diverse array of bioactive molecules, including proteins, lipids, and nucleic acids, to recipient cells. Recent studies have shown that EVs derived from various cell types, including mesenchymal stromal cells (MSCs), retinal pigment epithelium cells, and endothelial cells, have therapeutic potential in ocular disorders, such as corneal injury and diabetic retinopathy. EVs exert their effects through various mechanisms, including promoting cell survival, reducing inflammation, and inducing tissue regeneration. Furthermore, EVs have shown …

Local Ocular Safety Of The Subconjunctival Injection Of Cetuximab In Rabbits, Hossein Aghaei, Ahmad Kheirkhah, Ali Mohammad Alizadeh, Acieh Es'haghi, Roshanak Aliakbar-Navahi, Zahra Keikha, Samira Chaibakhsh

Faculty, Staff and Student Publications

BACKGROUND: To evaluate the safety of different doses of subconjunctival cetuximab in rabbits.

METHODS: After general anesthesia rabbits received a subconjunctival injection of 2.5 mg in 0.5 ml, 5 mg in 1 ml, and 10 mg in 2 ml of cetuximab in their right eyes (two rabbits in each group). A similar volume of normal saline solution was injected subconjunctivally in the left eyes. The histopathologic changes were evaluated after enucleation with the aid of H&E staining.

RESULTS: No significant difference were observed between the treated and control eyes in terms of conjunctival inflammation, goblet cell density, or limbal blood …

Autophagy Requirements For Eye Lens Differentiation And Transparency, Lisa Brennan, M Joseph Costello, J Fielding Hejtmancik, A. Menko, S Amer Riazuddin, Alan Shiels, Marc Kantorow

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Recent evidence points to autophagy as an essential cellular requirement for achieving the mature structure, homeostasis, and transparency of the lens. Collective evidence from multiple laboratories using chick, mouse, primate, and human model systems provides evidence that classic autophagy structures, ranging from double-membrane autophagosomes to single-membrane autolysosomes, are found throughout the lens in both undifferentiated lens epithelial cells and maturing lens fiber cells. Recently, key autophagy signaling pathways have been identified to initiate critical steps in the lens differentiation program, including the elimination of organelles to form the core lens organelle-free zone. Other recent studies using ex vivo lens culture …

Tnf-Α And Nf-Κb Signaling Play A Critical Role In Cigarette Smoke-Induced Epithelial-Mesenchymal Transition Of Retinal Pigment Epithelial Cells In Proliferative Vitreoretinopathy, Victor Wang, Alison Heffer, Elisa Roztocil, Steven E Feldon, Richard T Libby, Collynn F Woeller, Ajay E Kuriyan

Wills Eye Hospital Papers

Proliferative vitreoretinopathy (PVR) is characterized by the growth and contraction of cellular membranes within the vitreous cavity and on both surfaces of the retina, resulting in recurrent retinal detachments and poor visual outcomes. Proinflammatory cytokines like tumor necrosis factor alpha (TNFα) have been associated with PVR and the epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells. Cigarette smoke is the only known modifiable risk factor for PVR, but the mechanisms are unclear. The purpose of this study was to examine the impact of cigarette smoke on the proinflammatory TNFα/NF-κB/Snail pathway in RPE cells to better understand the mechanisms through …

Divergent Outer Retinal Circuits Drive Image And Non-Image Visual Behaviors, Corinne Beier, Ulisse Bocchero, Lior Levy, Zhijing Zhang, Nange Jin, Stephen C Massey, Christophe P Ribelayga, Kirill Martemyanov, Samer Hattar, Johan Pahlberg

Faculty, Staff and Student Publications

Image- and non-image-forming vision are essential for animal behavior. Here we use genetically modified mouse lines to examine retinal circuits driving image- and non-image-functions. We describe the outer retinal circuits underlying the pupillary light response (PLR) and circadian photoentrainment, two non-image-forming behaviors. Rods and cones signal light increments and decrements through the ON and OFF pathways, respectively. We find that the OFF pathway drives image-forming vision but cannot drive circadian photoentrainment or the PLR. Cone light responses drive image formation but fail to drive the PLR. At photopic levels, rods use the primary and secondary rod pathways to drive the …

Platelet And Erythrocyte Extravasation Across Inflamed Corneal Venules Depend On Cd18, Neutrophils, And Mast Cell Degranulation, Angie De La Cruz, Aubrey Hargrave, Sri Magadi, Justin A Courson, Paul T Landry, Wanyu Zhang, Fong W Lam, Monica A Bray, C Wayne Smith, Alan R Burns, Rolando E Rumbaut

Faculty, Staff and Student Publications

Platelet extravasation during inflammation is under-appreciated. In wild-type (WT) mice, a central corneal epithelial abrasion initiates neutrophil (PMN) and platelet extravasation from peripheral limbal venules. The same injury in mice expressing low levels of the β2-integrin, CD18 (CD18hypo mice) shows reduced platelet extravasation with PMN extravasation apparently unaffected. To better define the role of CD18 on platelet extravasation, we focused on two relevant cell types expressing CD18: PMNs and mast cells. Following corneal abrasion in WT mice, we observed not only extravasated PMNs and platelets but also extravasated erythrocytes (RBCs). Ultrastructural observations of engorged limbal venules showed platelets and RBCs …

Cgas Drives Noncanonical-Inflammasome Activation In Age-Related Macular Degeneration, Nagaraj Kerur, Shinichi Fukuda, Daipayan Banerjee, Younghee Kim, Dongxu Fu, Ivana Apicella, Akhil Varshney, Reo Yasuma, Benjamin J. Fowler, Elmira Baghdasaryan, Kenneth M. Marion, Xiwen Huang, Tetsuhiro Yasuma, Yoshio Hirano, Vlad Serbulea, Meenakshi Ambati, Vidya L. Ambati, Yuji Kajiwara, Kameshwari Ambati, Shuichiro Hirahara, Ana Bastos-Carvalho, Yuichiro Ogura, Hiroko Terasaki, Tetsuro Oshika, Kyung Bo Kim, David R. Hinton, Norbert Leitinger, John C. Cambier, Joseph D. Buxbaum, M. Cristina Kenney, Bradley D. Gelfand, Jayakrishna Ambati

Ophthalmology and Visual Science Faculty Publications

Geographic atrophy is a blinding form of age-related macular degeneration characterized by retinal pigmented epithelium (RPE) death; the RPE also exhibits DICER1 deficiency, resultant accumulation of endogenous Alu-retroelement RNA, and NLRP3-inflammasome activation. How the inflammasome is activated in this untreatable disease is largely unknown. Here we demonstrate that RPE degeneration in human-cell-culture and mouse models is driven by a noncanonical-inflammasome pathway that activates caspase-4 (caspase-11 in mice) and caspase-1, and requires cyclic GMP-AMP synthase (cGAS)-dependent interferon-β production and gasdermin D-dependent interleukin-18 secretion. Decreased DICER1 levels or Alu-RNA accumulation triggers cytosolic escape of mitochondrial DNA, which engages cGAS. Moreover, caspase-4, gasdermin …

GabaB Receptor Attenuation Of GabaA Currents In Neurons Of The Mammalian Central Nervous System, Wen Shen, Changlong Nan, Peter T. Nelson, Harris Ripps, Malcolm M. Slaughter

Pathology and Laboratory Medicine Faculty Publications

Ionotropic receptors are tightly regulated by second messenger systems and are often present along with their metabotropic counterparts on a neuron's plasma membrane. This leads to the hypothesis that the two receptor subtypes can interact, and indeed this has been observed in excitatory glutamate and inhibitory GABA receptors. In both systems the metabotropic pathway augments the ionotropic receptor response. However, we have found that the metabotropic GABA_B receptor can suppress the ionotropic GABA_A receptor current, in both the in vitro mouse retina and in human amygdala membrane fractions. Expression of amygdala membrane microdomains in Xenopus oocytes by microtransplantation …

Naturally Occurring Deletion Mutants Of The Pig-Specific, Intestinal Crypt Epithelial Cell Protein Clca4b Without Apparent Phenotype., Stephanie Plog, Nikolai Klymiuk, Stefanie Binder, Matthew J. Van Hook, Wallace B. Thoreson, Achim D. Gruber, Lars Mundhenk

Journal Articles: Ophthalmology

The human CLCA4 (chloride channel regulator, calcium-activated) modulates the intestinal phenotype of cystic fibrosis (CF) patients via an as yet unknown pathway. With the generation of new porcine CF models, species-specific differences between human modifiers of CF and their porcine orthologs are considered critical for the translation of experimental data. Specifically, the porcine ortholog to the human CF modulator gene CLCA4 has recently been shown to be duplicated into two separate genes, CLCA4a and CLCA4b. Here, we characterize the duplication product, CLCA4b, in terms of its genomic structure, tissue and cellular expression patterns as well as its in vitro electrophysiological …

Ca2+ Diffusion Through Endoplasmic Reticulum Supports Elevated Intraterminal Ca2+ Levels Needed To Sustain Synaptic Release From Rods In Darkness., Minghui Chen, Matthew J. Van Hook, Wallace B. Thoreson

Journal Articles: Ophthalmology

UNLABELLED: In addition to vesicle release at synaptic ribbons, rod photoreceptors are capable of substantial slow release at non-ribbon release sites triggered by Ca(2+)-induced Ca(2+) release (CICR) from intracellular stores. To maintain CICR as rods remain depolarized in darkness, we hypothesized that Ca(2+) released into the cytoplasm from terminal endoplasmic reticulum (ER) can be replenished continuously by ions diffusing within the ER from the soma. We measured [Ca(2+)] changes in cytoplasm and ER of rods from Ambystoma tigrinum retina using various dyes. ER [Ca(2+)] changes were measured by loading ER with fluo-5N and then washing dye from the cytoplasm with …

Powerful Anti-Tumor And Anti-Angiogenic Activity Of A New Anti-Vascular Endothelial Growth Factor Receptor 1 Peptide In Colorectal Cancer Models, Valeria Cicatiello, Ivana Apicella, Laura Tudisco, Valeria Tarallo, Luigi Formisano, Annamaria Sandomenico, Younghee Kim, Ana Bastos-Carvalho, Augusto Orlandi, Jayakrishna Ambati, Menotti Ruvo, Roberto Bianco, Sandro De Falco

Ophthalmology and Visual Science Faculty Publications

To assess the therapeutic outcome of selective block of VEGFR1, we have evaluated the activity of a new specific antagonist of VEGFR1, named iVR1 (inhibitor of VEGFR1), in syngenic and xenograft colorectal cancer models, in an artificial model of metastatization, and in laser-induced choroid neovascularization. iVR1 inhibited tumor growth and neoangiogenesis in both models of colorectal cancer, with an extent similar to that of bevacizumab, a monoclonal antibody anti-VEGF-A. It potently inhibited VEGFR1 phosphorylation in vivo, determining a strong inhibition of the recruitment of monocyte-macrophages and of mural cells as confirmed, in vitro, by the ability to inhibit …

Swelling And Eicosanoid Metabolites Differentially Gate Trpv4 Channels In Retinal Neurons And Glia., Daniel A. Ryskamp, Andrew O. Jo, Amber M M. Frye, Felix Vazquez-Chona, Nanna Macaulay, Wallace B. Thoreson, David Križaj

Journal Articles: Ophthalmology

Activity-dependent shifts in ionic concentrations and water that accompany neuronal and glial activity can generate osmotic forces with biological consequences for brain physiology. Active regulation of osmotic gradients and cellular volume requires volume-sensitive ion channels. In the vertebrate retina, critical support to volume regulation is provided by Müller astroglia, but the identity of their osmosensor is unknown. Here, we identify TRPV4 channels as transducers of mouse Müller cell volume increases into physiological responses. Hypotonic stimuli induced sustained [Ca(2+)]i elevations that were inhibited by TRPV4 antagonists and absent in TRPV4(-/-) Müller cells. Glial TRPV4 signals were phospholipase A2- and cytochrome P450-dependent, …

Retinal Angiogenesis Suppression Through Small Molecule Activation Of P53, Sai H. Chavala, Younghee Kim, Laura Tudisco, Valeria Cicatiello, Till Milde, Nagaraj Kerur, Nidia Claros, Susan Yanni, Victor H. Guaiquil, William W. Hauswirth, John S. Penn, Shahin Rafii, Sandro De Falco, Thomas C. Lee, Jayakrishna Ambati

Ophthalmology and Visual Science Faculty Publications

Neovascular age-related macular degeneration is a leading cause of irreversible vision loss in the Western world. Cytokine-targeted therapies (such as anti-vascular endothelial growth factor) are effective in treating pathologic ocular angiogenesis, but have not led to a durable effect and often require indefinite treatment. Here, we show that Nutlin-3, a small molecule antagonist of the E3 ubiquitin protein ligase MDM2, inhibited angiogenesis in several model systems. We found that a functional p53 pathway was essential for Nutlin-3-mediated retinal antiangiogenesis and disruption of the p53 transcriptional network abolished the antiangiogenic activity of Nutlin-3. Nutlin-3 did not inhibit established, mature blood vessels …

Withaferin A Effectively Targets Soluble Vimentin In The Glaucoma Filtration Surgical Model Of Fibrosis, Paola Bargagna-Mohan, Sunil P. Deokule, Kyle G. Thompson, John Wizeman, Cidambi Srinivasan, Sunil Vooturi, Uday B. Kompella, Royce Mohan

Ophthalmology and Visual Science Faculty Publications

Withaferin A (WFA) is a natural product that binds to soluble forms of the type III intermediate filament (IF) vimentin. Currently, it is unknown under what pathophysiological contexts vimentin is druggable, as cytoskeltal vimentin-IFs are abundantly expressed. To investigate druggability of vimentin, we exploited rabbit Tenon's capsule fibroblast (RbTCF) cell cultures and the rabbit glaucoma filtration surgical (GFS) model of fibrosis. WFA potently caused G₀/G₁ cell cycle inhibition (IC₅₀ 25 nM) in RbTCFs, downregulating ubiquitin E3 ligase skp2 and inducing p27(Kip1) expression. Transforming growth factor (TGF)-ß-induced myofibroblast transformation caused development of cell spheroids with numerous elongated invadopodia, which WFA blocked …

Lateral Mobility Of L-Type Calcium Channels In Synaptic Terminals Of Retinal Bipolar Cells., Wallace B. Thoreson, Aaron J. Mercer, Karlene M. Cork, Robert J. Szalewski

Journal Articles: Ophthalmology

PURPOSE: Efficient and precise release of glutamate from retinal bipolar cells is ensured by the positioning of L-type Ca(2+) channels close to release sites at the base of the synaptic ribbon. We investigated whether Ca(2+) channels at bipolar cell ribbon synapses are fixed in position or capable of moving in the membrane.

METHODS: We tracked the movements of individual L-type Ca(2+) channels in bipolar cell terminals after labeling channels with quantum dots (QDs) attached to α(2)δ(4) accessory Ca(2+) channel subunits via intermediary antibodies.

RESULTS: We found that individual Ca(2+) channels moved within a confined domain of 0.13-0.15 μm(2) in bipolar …

Therapies For Neovascular Age-Related Macular Degeneration: Current Approaches And Pharmacologic Agents In Development., Mostafa Hanout, Daniel Ferraz, Mehreen Ansari, Natasha Maqsood, Saleema Kherani, Yasir J. Sepah, Nithya Rajagopalan, Mohamed Ibrahim, Diana V. Do, Quan Dong Nguyen

Journal Articles: Ophthalmology

As one of the leading causes of blindness, age-related macular degeneration (AMD) has remained at the epicenter of clinical research in ophthalmology. During the past decade, focus of researchers has ranged from understanding the role of vascular endothelial growth factor (VEGF) in the angiogenic cascades to developing new therapies for retinal vascular diseases. Anti-VEGF agents such as ranibizumab and aflibercept are becoming increasingly well-established therapies and have replaced earlier approaches such as laser photocoagulation or photodynamic therapy. Many other new therapeutic agents, which are in the early phase clinical trials, have shown promising results. The purpose of this paper is …

Rapid Synaptic Vesicle Endocytosis In Cone Photoreceptors Of Salamander Retina., Matthew J. Van Hook, Wallace B. Thoreson

Journal Articles: Ophthalmology

Following synaptic vesicle exocytosis, neurons retrieve the fused membrane by a process of endocytosis to provide a supply of vesicles for subsequent release and maintain the presynaptic active zone. Rod and cone photoreceptors use a specialized structure called the synaptic ribbon that enables them to sustain high rates of neurotransmitter release. They must also employ mechanisms of synaptic vesicle endocytosis capable of keeping up with release. While much is known about endocytosis at another retinal ribbon synapse, that of the goldfish Mb1 bipolar cell, less is known about endocytosis in photoreceptors. We used capacitance recording techniques to measure vesicle membrane …

Corneal Replication Is An Interferon Response-Independent Bottleneck For Virulence Of Herpes Simplex Virus 1 In The Absence Of Virion Host Shutoff, Tracy J. Pasieka, Vineet D. Menachery, Pamela C. Rosato, David A. Leib

Dartmouth Scholarship

Herpes simplex viruses lacking the virion host shutoff function (Δvhs) are avirulent and hypersensitive to type I and type II interferon (IFN). In this study, we demonstrate that even in the absence of IFN responses in AG129 (IFN-αβγR^−/−) mice, Δvhs remains highly attenuated via corneal infection but is fully virulent via intracranial infection. The data demonstrate that the interferon-independent inherent replication defect of Δvhs has a significant impact upon peripheral replication and neuroinvasion.