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Hanna K, Nieves J, Dowd C, Bender KO, Sharma P, Singh B, Renz M, Ver Hoeve JN, Cepeda D, Gelfman CM, Riley BE, Grishanin RN. Preclinical evaluation of ADVM-062, a novel intravitreal gene therapy vector for the treatment of blue cone monochromacy. Mol Ther 2023; 31:2014-2027. [PMID: 36932675 PMCID: PMC10362383 DOI: 10.1016/j.ymthe.2023.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/14/2023] [Accepted: 03/11/2023] [Indexed: 03/18/2023] Open
Abstract
Blue cone monochromacy (BCM) is a rare X-linked retinal disease characterized by the absence of L- and M-opsin in cone photoreceptors, considered a potential gene therapy candidate. However, most experimental ocular gene therapies utilize subretinal vector injection which would pose a risk to the fragile central retinal structure of BCM patients. Here we describe the use of ADVM-062, a vector optimized for cone-specific expression of human L-opsin and administered using a single intravitreal (IVT) injection. Pharmacological activity of ADVM-062 was established in gerbils, whose cone-rich retina naturally lacks L-opsin. A single IVT administration dose of ADVM-062 effectively transduced gerbil cone photoreceptors and produced a de novo response to long-wavelength stimuli. To identify potential first-in-human doses we evaluated ADVM-062 in non-human primates. Cone-specific expression of ADVM-062 in primates was confirmed using ADVM-062.myc, a vector engineered with the same regulatory elements as ADVM-062. Enumeration of human OPN1LW.myc-positive cones demonstrated that doses ≥3 × 1010 vg/eye resulted in transduction of 18%-85% of foveal cones. A Good Laboratory Practice (GLP) toxicology study established that IVT administration of ADVM-062 was well tolerated at doses that could potentially achieve clinically meaningful effect, thus supporting the potential of ADVM-062 as a one-time IVT gene therapy for BCM.
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Affiliation(s)
- Kelly Hanna
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA
| | - Julio Nieves
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA
| | - Christine Dowd
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA
| | | | - Pallavi Sharma
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA
| | - Baljit Singh
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA
| | - Mark Renz
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA
| | | | - Diana Cepeda
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA
| | | | - Brigit E Riley
- Adverum Biotechnologies, Inc., Redwood City, CA 94063, USA.
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Nork TM, Kim CBY, Katz AW, Rasmussen CA, Banghart M, Ver Hoeve JN. Multifocal electroretinography increases following experimental glaucoma in nonhuman primates with retinal ganglion cell axotomy. Doc Ophthalmol 2023; 146:97-112. [PMID: 36763214 PMCID: PMC10284020 DOI: 10.1007/s10633-023-09922-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 01/20/2023] [Indexed: 02/11/2023]
Abstract
PURPOSE To determine whether short-latency changes in multifocal electroretinography (mfERG) observed in experimental glaucoma (EG) are secondary solely to retinal ganglion cell (RGC) loss or whether there is a separate contribution from elevated intraocular pressure (IOP). METHODS Prior to operative procedures, a series of baseline mfERGs were recorded from six rhesus macaques using a 241-element unstretched stimulus. Animals then underwent hemiretinal endodiathermy axotomy (HEA) by placing burns along the inferior 180° of the optic nerve margin in the right eye (OD). mfERG recordings were obtained in each animal at regular intervals following for 3-4 months to allow stabilization of the HEA effects. Laser trabecular meshwork destruction (LTD) to elevate IOP was then performed; first-order kernel (K1) waveform root-mean-square (RMS) amplitudes for the short-latency segment of the mfERG wave (9-35 ms) were computed for two 7-hexagon groupings-the first located within the superior (non-axotomized) macula and the second within the inferior (axotomized) macula. Immunohistochemistry for glial fibrillary acidic protein (GFAP) was done. RESULTS By 3 months post HEA, there was marked thinning of the inferior nerve fiber layer as measured by optical coherence tomography. Compared with baseline, no statistically significant changes in 9-35 ms K1 RMS amplitudes were evident in either the axotomized or non-axotomized portions of the macula. Following LTD, mean IOP in HEA eyes rose to 46 ± 9 compared with 20 ± 2 mmHg (SD) in the fellow control eyes. In the HEA + EG eyes, statistically significant increases in K1 RMS amplitude were present in both the axotomized inferior and non-axotomized superior portions of the OD retinas. No changes in K1 RMS amplitude were found in the fellow control eyes from baseline to HEA epoch, but there was a smaller increase from baseline to HEA + EG. Upregulation of GFAP in the Müller cells was evident in both non-axotomized and axotomized retina in eyes with elevated IOP. CONCLUSIONS The RMS amplitudes of the short-latency mfERG K1 waveforms are not altered following axotomy but undergo marked increases following elevated IOP. This suggests that the increase in mfERG amplitude was not solely a result of RGC loss and may reflect photoreceptor and bipolar cell dysfunction and/or changes in Müller cells.
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Affiliation(s)
- T Michael Nork
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA.
| | - Charlene B Y Kim
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Alexander W Katz
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Carol A Rasmussen
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Mark Banghart
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - James N Ver Hoeve
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
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Bradfield YS, Ver Hoeve JN, Aul B, Struck MC. Use of sweep visual evoked potential in preverbal children with optic nerve hypoplasia. J AAPOS 2022; 26:131.e1-131.e6. [PMID: 35577018 DOI: 10.1016/j.jaapos.2022.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 01/11/2022] [Accepted: 01/21/2022] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate sweep VEP (sVEP) in preverbal children with optic nerve hypoplasia (ONH) and to assess associations between sVEP results, patient clinical characteristics and future recognition visual acuity. METHODS The medical records of children with ONH who had sVEP testing and documented recognition visual acuity at the University of Wisconsin from 2005 to 2013 were reviewed retrospectively. Optic nerve size, amblyopia treatment, and neurologic diagnoses were collected. RESULTS A total of 57 patients were included: 41 (71%) with bilateral ONH and 27 (47%) with neurologic abnormality. Mean age at initial sVEP was 13.3 months (range, 1-32). Mean duration between initial sVEP and final recognition acuity was 5.5 years (range, 3.5-7). Sweep VEP was associated with ONH severity (P < 0.05). Sweep VEP, and the combination of ONH severity and neurologic status, were significant predictors (P < 0.05) of logMAR optotype acuity, together accounting for 54%-61% of the variance in final recognition acuity. CONCLUSIONS Sweep VEP in preverbal children with ONH depends on ONH severity and correlates with final recognition visual acuity. Children with milder degrees of ONH without neurologic abnormalities had better final vision, and patients with severe ONH and neurologic diagnoses had worse vision outcomes.
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Affiliation(s)
- Yasmin S Bradfield
- University of Wisconsin Department of Ophthalmology and Visual Sciences.
| | - James N Ver Hoeve
- University of Wisconsin Department of Ophthalmology and Visual Sciences
| | - Bryce Aul
- University of Wisconsin Department of Ophthalmology and Visual Sciences
| | - Michael C Struck
- University of Wisconsin Department of Ophthalmology and Visual Sciences
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Etheridge T, Kellom ER, Sullivan R, Ver Hoeve JN, Schmitt MA. Ocular evaluation and genetic test for an early Alström Syndrome diagnosis. Am J Ophthalmol Case Rep 2020; 20:100873. [PMID: 32944671 PMCID: PMC7481517 DOI: 10.1016/j.ajoc.2020.100873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 07/18/2020] [Accepted: 08/09/2020] [Indexed: 11/05/2022] Open
Abstract
Purpose We present 3 cases of Alström syndrome (ALMS) that highlight the importance of the ophthalmic exam, as well as the diagnostic challenges and management considerations of this ultra-rare disease. Observations The first case is of a 2-year-old boy with history of spasmus nutans who presented with head bobbing and nystagmus. The second patient is a 5-year-old boy with history of infantile dilated cardiomyopathy status post heart transplant, Burkitt lymphoma status post chemotherapy, obesity, global developmental delay, and high hyperopia previously thought to have cortical visual impairment secondary to heart surgery/possible ischemic event. This patient presented with nystagmus, photophobia, and reduced vision. The third case involves a 8-year-old boy with history of obesity, bilateral optic nerve atrophy, hyperopic astigmatism, exotropia, and nystagmus. Upon presentation to the consulting pediatric ophthalmologist, none of the patients had yet been diagnosed with ALMS. All 3 cases were subsequently found to have an electroretinogram (ERG) that exhibited severe global depression and to carry ALMS1 pathogenic variants. Conclusions and Importance ALMS is an autosomal recessive disease caused by ALMS1 variations, characterized by cone-rod dystrophy, obesity, progressive sensorineural hearing loss, cardiomyopathy, insulin resistance, and multiorgan dysfunction. Retinal dystrophy diagnosis is critical given clinical criteria and detection rates of genetic testing. Early diagnosis is extremely important because progression to flat ERG leads to the inability to differentiate between rod-cone or cone-rod involvement, either of which have their own differential diagnoses. In our series, the ophthalmic exam and abnormal ERG prompted further genetic testing and the subsequent diagnosis of ALMS. Multidisciplinary care ensures the best possible outcome with the ophthalmologist playing a key role.
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Key Words
- ALMS, Alström Syndrome
- ALMS1 gene
- APD, Afferent pupillary defect
- Alström syndrome
- Autosomal recessive
- BMI, Body mass index
- CHF, Congestive heart failure
- CLIA, Clinical Laboratory Improvement Amendments
- Cone-rod dystrophy
- DA, Dark-adapted
- DFE, Dilated fundus exam
- EEG, Electroencephalogram
- ERG, Electroretinogram
- EUA, Exam under anesthesia
- FAF, Fundus autofluorescence
- IGF, Insulin-like growth factor
- IR, Insulin resistance
- ISCEV, International Society for Clinical Electrophysiology of Vision
- LA, Light-adapted
- MRI, Magnetic resonance imaging
- OCT, Optical coherence tomography
- OD, Right eye
- OPs, Oscillatory potentials
- OS, Left eye
- OU, Both eyes
- RPE, Retinal pigment epithelium
- T2DM, Type II diabetes mellitus
- VA, Visual acuity
- VEP, Visual evoked potential
- VGB, Vigabatrin
- cDNA, complementary DNA
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Affiliation(s)
- Tyler Etheridge
- University of Wisconsin School of Medicine and Public Health, Department of Ophthalmology & Visual Sciences, Madison, WI, United States
| | - Elizabeth R Kellom
- University of Wisconsin School of Medicine and Public Health, Department of Ophthalmology & Visual Sciences, Madison, WI, United States
| | - Rachel Sullivan
- University of Wisconsin School of Medicine and Public Health, Department of Ophthalmology & Visual Sciences, Madison, WI, United States
| | - James N Ver Hoeve
- University of Wisconsin School of Medicine and Public Health, Department of Ophthalmology & Visual Sciences, Madison, WI, United States
| | - Melanie A Schmitt
- University of Wisconsin School of Medicine and Public Health, Department of Ophthalmology & Visual Sciences, Madison, WI, United States
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Oikawa K, Ver Hoeve JN, Teixeira LBC, Snyder KC, Kiland JA, Ellinwood NM, McLellan GJ. Sub-region-Specific Optic Nerve Head Glial Activation in Glaucoma. Mol Neurobiol 2020; 57:2620-2638. [PMID: 32266645 DOI: 10.1007/s12035-020-01910-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/23/2020] [Indexed: 12/22/2022]
Abstract
Glaucoma, a multifactorial neurodegenerative disease characterized by progressive loss of retinal ganglion cells and their axons in the optic nerve, is a leading cause of irreversible vision loss. Intraocular pressure (IOP) is a risk factor for axonal damage, which initially occurs at the optic nerve head (ONH). Complex cellular and molecular mechanisms involved in the pathogenesis of glaucomatous optic neuropathy remain unclear. Here we define early molecular events in the ONH in an inherited large animal glaucoma model in which ONH structure resembles that of humans. Gene expression profiling of ONH tissues from rigorously phenotyped feline subjects with early-stage glaucoma and precisely age-matched controls was performed by RNA-sequencing (RNA-seq) analysis and complementary bioinformatic approaches applied to identify molecular processes and pathways of interest. Immunolabeling supported RNA-seq findings while providing cell-, region-, and disease stage-specific context in the ONH in situ. Transcriptomic evidence for cell proliferation and immune/inflammatory responses is identifiable in early glaucoma, soon after IOP elevation and prior to morphologically detectable axon loss, in this large animal model. In particular, proliferation of microglia and oligodendrocyte precursor cells is a prominent feature of early-stage, but not chronic, glaucoma. ONH microgliosis is a consistent hallmark in both early and chronic stages of glaucoma. Molecular pathways and cell type-specific responses strongly implicate toll-like receptor and NF-κB signaling in early glaucoma pathophysiology. The current study provides critical insights into molecular pathways, highly dependent on cell type and sub-region in the ONH even prior to irreversible axon degeneration in glaucoma.
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Affiliation(s)
- Kazuya Oikawa
- Department of Surgical Sciences, University of Wisconsin-Madison, Madison, WI, USA
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, 1300 University Avenue, Madison, WI, 53706, USA
- McPherson Eye Research Institute, Madison, WI, USA
| | - James N Ver Hoeve
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, 1300 University Avenue, Madison, WI, 53706, USA
- McPherson Eye Research Institute, Madison, WI, USA
| | - Leandro B C Teixeira
- McPherson Eye Research Institute, Madison, WI, USA
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Kevin C Snyder
- Department of Surgical Sciences, University of Wisconsin-Madison, Madison, WI, USA
- McPherson Eye Research Institute, Madison, WI, USA
| | - Julie A Kiland
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, 1300 University Avenue, Madison, WI, 53706, USA
| | | | - Gillian J McLellan
- Department of Surgical Sciences, University of Wisconsin-Madison, Madison, WI, USA.
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, 1300 University Avenue, Madison, WI, 53706, USA.
- McPherson Eye Research Institute, Madison, WI, USA.
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Chan K, Hoon M, Pattnaik BR, Ver Hoeve JN, Wahlgren B, Gloe S, Williams J, Wetherbee B, Kiland JA, Vogel KR, Jansen E, Salomons G, Walters D, Roullet JB, Gibson K M, McLellan GJ. Vigabatrin-Induced Retinal Functional Alterations and Second-Order Neuron Plasticity in C57BL/6J Mice. Invest Ophthalmol Vis Sci 2020; 61:17. [PMID: 32053727 PMCID: PMC7326505 DOI: 10.1167/iovs.61.2.17] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 11/07/2019] [Indexed: 12/13/2022] Open
Abstract
Purpose Vigabatrin (VGB) is an effective antiepileptic that increases concentrations of inhibitory γ-aminobutyric acid (GABA) by inhibiting GABA transaminase. Reports of VGB-associated visual field loss limit its clinical usefulness, and retinal toxicity studies in laboratory animals have yielded conflicting results. Methods We examined the functional and morphologic effects of VGB in C57BL/6J mice that received either VGB or saline IP from 10 to 18 weeks of age. Retinal structure and function were assessed in vivo by optical coherence tomography (OCT), ERG, and optomotor response. After euthanasia, retinas were processed for immunohistochemistry, and retinal GABA, and VGB quantified by mass spectrometry. Results No significant differences in visual acuity or total retinal thickness were identified between groups by optomotor response or optical coherence tomography, respectively. After 4 weeks of VGB treatment, ERG b-wave amplitude was enhanced, and amplitudes of oscillatory potentials were reduced. Dramatic rod and cone bipolar and horizontal cell remodeling, with extension of dendrites into the outer nuclear layer, was observed in retinas of VGB-treated mice. VGB treatment resulted in a mean 3.3-fold increase in retinal GABA concentration relative to controls and retinal VGB concentrations that were 20-fold greater than brain. Conclusions No evidence of significant retinal thinning or ERG a- or b-wave deficits were apparent, although we describe significant alterations in ERG b-wave and oscillatory potentials and in retinal cell morphology in VGB-treated C57BL/6J mice. The dramatic concentration of VGB in retina relative to the target tissue (brain), with a corresponding increase in retinal GABA, offers insight into the pathophysiology of VGB-associated visual field loss.
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Affiliation(s)
- Kore Chan
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, Madison, Wisconsin, United States
| | - Mrinalini Hoon
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, Madison, Wisconsin, United States
| | - Bikash R. Pattnaik
- McPherson Eye Research Institute, Madison, Wisconsin, United States
- Pediatrics Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - James N. Ver Hoeve
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, Madison, Wisconsin, United States
| | - Brad Wahlgren
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Shawna Gloe
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Jeremy Williams
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Brenna Wetherbee
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Julie A. Kiland
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Kara R. Vogel
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, Madison, Wisconsin, United States
| | - Erwin Jansen
- Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Gajja Salomons
- Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Dana Walters
- Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, Washington, United States
| | - Jean-Baptiste Roullet
- Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, Washington, United States
| | - K Michael Gibson
- Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, Washington, United States
| | - Gillian J. McLellan
- Department of Ophthalmology & Visual Science, University of Wisconsin–Madison, Madison, Wisconsin, United States
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, United States
- McPherson Eye Research Institute, Madison, Wisconsin, United States
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Raghunathan V, Eaton JS, Christian BJ, Morgan JT, Ver Hoeve JN, Yang CYC, Gong H, Rasmussen CA, Miller PE, Russell P, Nork TM, Murphy CJ. Biomechanical, ultrastructural, and electrophysiological characterization of the non-human primate experimental glaucoma model. Sci Rep 2017; 7:14329. [PMID: 29085025 PMCID: PMC5662689 DOI: 10.1038/s41598-017-14720-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 10/13/2017] [Indexed: 11/08/2022] Open
Abstract
Laser-induced experimental glaucoma (ExGl) in non-human primates (NHPs) is a common animal model for ocular drug development. While many features of human hypertensive glaucoma are replicated in this model, structural and functional changes in the unlasered portions of trabecular meshwork (TM) of laser-treated primate eyes are understudied. We studied NHPs with ExGl of several years duration. As expected, ExGl eyes exhibited selective reductions of the retinal nerve fiber layer that correlate with electrophysiologic measures documenting a link between morphologic and elctrophysiologic endpoints. Softening of unlasered TM in ExGl eyes compared to untreated controls was observed. The degree of TM softening was consistent, regardless of pre-mortem clinical findings including severity of IOP elevation, retinal nerve fiber layer thinning, or electrodiagnostic findings. Importantly, this softening is contrary to TM stiffening reported in glaucomatous human eyes. Furthermore, microscopic analysis of unlasered TM from eyes with ExGl demonstrated TM thinning with collapse of Schlemm's canal; and proteomic analysis confirmed downregulation of metabolic and structural proteins. These data demonstrate unexpected and compensatory changes involving the TM in the NHP model of ExGl. The data suggest that compensatory mechanisms exist in normal animals and respond to elevated IOP through softening of the meshwork to increase outflow.
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Affiliation(s)
- VijayKrishna Raghunathan
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California - Davis, Davis, California, 95616, United States of America
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America
- The Ocular Surface Institute, Department of Basic Sciences, College of Optometry, University of Houston, Houston, Texas, 77204, United States of America
| | - J Seth Eaton
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California - Davis, Davis, California, 95616, United States of America
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America
| | - Brian J Christian
- Covance Laboratories, Inc., Madison, Wisconsin, 53704, United States of America
| | - Joshua T Morgan
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California - Davis, Davis, California, 95616, United States of America
| | - James N Ver Hoeve
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin - Madison, Madison, Wisconsin, 53792, United States of America
| | - Chen-Yuan Charlie Yang
- Department of Anatomy and Neurobiology, School of Medicine, Boston University, Boston, Massachusetts, 02118, United States of America
- Department of Ophthalmology, School of Medicine, Boston University, Boston, Massachusetts, 02118, United States of America
| | - Haiyan Gong
- Department of Anatomy and Neurobiology, School of Medicine, Boston University, Boston, Massachusetts, 02118, United States of America
- Department of Ophthalmology, School of Medicine, Boston University, Boston, Massachusetts, 02118, United States of America
| | - Carol A Rasmussen
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin - Madison, Madison, Wisconsin, 53792, United States of America
| | - Paul E Miller
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin - Madison, Madison, Wisconsin, 53706, United States of America
| | - Paul Russell
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California - Davis, Davis, California, 95616, United States of America
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America
| | - T Michael Nork
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America.
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin - Madison, Madison, Wisconsin, 53792, United States of America.
| | - Christopher J Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California - Davis, Davis, California, 95616, United States of America.
- Ocular Services On Demand (OSOD), Madison, Wisconsin, 53719, United States of America.
- Department of Ophthalmology & Vision Science, School of Medicine, University of California - Davis, Sacramento, California, 95817, United States of America.
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Ye GJ, Budzynski E, Sonnentag P, Nork TM, Miller PE, Sharma AK, Ver Hoeve JN, Smith LM, Arndt T, Calcedo R, Gaskin C, Robinson PM, Knop DR, Hauswirth WW, Chulay JD. Safety and Biodistribution Evaluation in Cynomolgus Macaques of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia. HUM GENE THER CL DEV 2016; 27:37-48. [PMID: 27003753 DOI: 10.1089/humc.2015.164] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Applied Genetic Technologies Corporation (AGTC) is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated viral (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. We report here results of a study evaluating the safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in cynomolgus macaques. Three groups of animals (n = 2 males and 2 females per group) received a subretinal injection in one eye of 300 μl containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two concentrations (4 × 10(11) or 4 × 10(12) vector genomes/ml) and were evaluated over a 3-month period before being euthanized. Administration of rAAV2tYF-PR1.7-hCNGB3 was associated with a dose-related anterior and posterior segment inflammatory response that was greater than that observed in eyes injected with the vehicle control. Most manifestations of inflammation improved over time except that vitreous cells persisted in vector-treated eyes until the end of the study. One animal in the lower vector dose group was euthanized on study day 5, based on a clinical diagnosis of endophthalmitis. There were no test article-related effects on intraocular pressure, visual evoked potential responses, hematology or clinical chemistry parameters, or gross necropsy observations. Histopathological examination demonstrated minimal mononuclear infiltrates in all vector-injected eyes. Serum anti-AAV antibodies developed in all vector-injected animals. No animals developed antibodies to CNGB3. Biodistribution studies demonstrated high levels of vector DNA in the injected eye but minimal or no vector DNA in any other tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations.
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Affiliation(s)
- Guo-jie Ye
- 1 Applied Genetic Technologies Corporation (AGTC) , Alachua, FL
| | | | | | | | | | | | | | - Leia M Smith
- 4 Laboratory Corporation of America Holdings , Seattle, WA
| | | | | | | | | | - David R Knop
- 1 Applied Genetic Technologies Corporation (AGTC) , Alachua, FL
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Ye GJ, Budzynski E, Sonnentag P, Nork TM, Miller PE, McPherson L, Ver Hoeve JN, Smith LM, Arndt T, Mandapati S, Robinson PM, Calcedo R, Knop DR, Hauswirth WW, Chulay JD. Safety and Biodistribution Evaluation in CNGB3-Deficient Mice of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia. HUM GENE THER CL DEV 2016; 27:27-36. [PMID: 27003752 DOI: 10.1089/humc.2015.163] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Applied Genetic Technologies Corporation (AGTC) is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated virus (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. We report here results of a study evaluating safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in CNGB3-deficient mice. Three groups of animals (n = 35 males and 35 females per group) received a subretinal injection in one eye of 1 μl containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two dose concentrations (1 × 10(12) or 4.2 × 10(12) vg/ml) and were euthanized 4 or 13 weeks later. There were no test-article-related changes in clinical observations, body weights, food consumption, ocular examinations, clinical pathology parameters, organ weights, or macroscopic observations at necropsy. Cone-mediated electroretinography (ERG) responses were detected after vector administration in the treated eyes in 90% of animals in the higher dose group and 31% of animals in the lower dose group. Rod-mediated ERG responses were reduced in the treated eye for all groups, with the greatest reduction in males given the higher dose of vector, but returned to normal by the end of the study. Microscopic pathology results demonstrated minimal mononuclear cell infiltrates in the retina and vitreous of some animals at the interim euthanasia and in the vitreous of some animals at the terminal euthanasia. Serum anti-AAV antibodies developed in most vector-injected animals. No animals developed antibodies to hCNGB3. Biodistribution studies demonstrated high levels of vector DNA in vector-injected eyes but little or no vector DNA in nonocular tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations.
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Affiliation(s)
- Guo-jie Ye
- 1 Applied Genetic Technologies Corporation (AGTC) , Alachua, Florida
| | | | | | | | | | | | | | - Leia M Smith
- 4 Laboratory Corporation of America Holdings , Seattle, Washington
| | - Tara Arndt
- 2 Covance Laboratories Inc. , Madison, Wisconsin
| | - Savitri Mandapati
- 1 Applied Genetic Technologies Corporation (AGTC) , Alachua, Florida
| | | | | | - David R Knop
- 1 Applied Genetic Technologies Corporation (AGTC) , Alachua, Florida
| | | | - Jeffrey D Chulay
- 1 Applied Genetic Technologies Corporation (AGTC) , Alachua, Florida
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Teixeira LBC, Hoeve JNV, Mayer JA, Dubielzig RR, Smith CM, Radcliff AB, Duncan ID. Modeling the Chronic Loss of Optic Nerve Axons and the Effects on the Retinal Nerve Fiber Layer Structure in Primary Disorder of Myelin. Invest Ophthalmol Vis Sci 2016; 57:4859-4868. [PMID: 27654412 PMCID: PMC5032912 DOI: 10.1167/iovs.16-19871] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Purpose We determined whether the chronic lack of optic nerve myelination and subsequent axon loss is associated with optical coherence tomography (OCT) changes in the retinal nerve fiber layer (RNFL), and whether this models what occurs in multiple sclerosis (MS) and confers its use as a surrogate marker for axon degeneration. Methods Using an animal model of Pelizaeus-Merzbacher disease (shp) bilateral longitudinal measurements of the peripapillary RNFL (spectral-domain OCT), electroretinograms (ERG), and visual evoked potentials (VEP) were performed in affected and control animals from 5 months to 2 years and in individual animals at single time points. Light and electron microscopy of the optic nerve and retina and histomorphometric measurements of the RNFL were compared to OCT data. Results Of the shp animals, 17% had an average reduction of OCT RNFL thickness on the superior retinal quadrant compared to controls (P < 0.05). Electroretinograms showed normal photopic A- and B-waves but flash VEPs were disorganized in shp animals. Morphologically, the shp retinas and optic nerves revealed significant RNFL thinning (P < 0.001) without retinal ganglion cell (RGC) loss, decrease total and relative retinal axonal area, and loss of optic nerve axons. There was strong positive correlation between OCT and morphometric RNFL thickness measurements (r = 0.878, P = 0.004). Conclusion The loss of optic nerve axons demonstrated in the shp model resulted in moderate thinning of the RNFL confirmed by OCT and histology. These results indicate that OCT-derived RNFL measurement can be a useful surrogate biomarker of optic nerve axon loss and potentially disease progression in demyelinating diseases.
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Affiliation(s)
- Leandro B C Teixeira
- Department of Pathobiological Sciences School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - James N Ver Hoeve
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Joshua A Mayer
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Richard R Dubielzig
- Department of Pathobiological Sciences School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Chelsey M Smith
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Abigail B Radcliff
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Ian D Duncan
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
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Ye GJ, Budzynski E, Sonnentag P, Miller PE, Sharma AK, Ver Hoeve JN, Howard K, Knop DR, Neuringer M, McGill T, Stoddard J, Chulay JD. Safety and Biodistribution Evaluation in Cynomolgus Macaques of rAAV2tYF-CB-hRS1, a Recombinant Adeno-Associated Virus Vector Expressing Retinoschisin. HUM GENE THER CL DEV 2016; 26:165-76. [PMID: 26390090 DOI: 10.1089/humc.2015.076] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Applied Genetic Technologies Corporation is developing rAAV2tYF-CB-hRS1, a recombinant adeno-associated virus (rAAV) vector for treatment of X-linked retinoschisis (XLRS), an inherited retinal disease characterized by splitting (schisis) of retinal layers causing poor vision. We report here results of a study evaluating the safety and biodistribution of rAAV2tYF-CB-hRS1 in normal cynomolgus macaques. Three groups of male animals (n = 6 per group) received an intravitreal injection in one eye of either vehicle, or rAAV2tYF-CB-hRS1 at one of two dose levels (4 × 10(10) or 4 × 10(11) vg/eye). Half the animals were sacrificed after 14 days and the others after 91 or 115 days. The intravitreal injection procedure was well tolerated in all groups. Serial ophthalmic examinations demonstrated a dose-related anterior and posterior segment inflammatory response that improved over time. There were no test article-related effects on intraocular pressure, electroretinography, visual evoked potential, hematology, coagulation, clinical chemistry, or gross necropsy observations. Histopathological examination demonstrated minimal or moderate mononuclear infiltrates in 6 of 12 vector-injected eyes. Immunohistochemical staining showed RS1 labeling of the ganglion cell layer at the foveal slope in vector-injected eyes at both dose levels. Serum anti-AAV antibodies were detected in 4 of 6 vector-injected animals at the day 15 sacrifice and all vector-injected animals at later time points. No animals developed antibodies to RS1. Biodistribution studies demonstrated high levels of vector DNA in the injected eye but minimal or no vector DNA in any other tissue. These results support the use of rAAV2tYF-CB-hRS1 in clinical studies in patients with XLRS.
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Affiliation(s)
- Guo-Jie Ye
- 1 Applied Genetic Technologies Corporation , Alachua, Florida
| | | | | | | | | | | | - Kellie Howard
- 4 Laboratory Corporation of America® Holdings , Seattle, Washington
| | - David R Knop
- 1 Applied Genetic Technologies Corporation , Alachua, Florida
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12
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Ye GJ, Budzynski E, Sonnentag P, Nork TM, Miller PE, Sharma AK, Hoeve JNV, Smith LM, Arndt T, Calcedo R, Gaskin C, Robinson PM, Knop DR, Hauswirth WW, Chulay JD. 88. Safety and Biodistribution Study of rAAV2tYF-PR1.7-hCNGB3 in Nonhuman Primates. Mol Ther 2016. [DOI: 10.1016/s1525-0016(16)32897-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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13
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Ye GJ, Budzynski E, Sonnentag P, Nork TM, Miller PE, McPherson L, Hoeve JNV, Smith LM, Arndt TA, Mandapati S, Robinson PM, Calcedo R, Knop DR, Hauswirth WW, Chulay JD. 299. Safety and Biodistribution Study of rAAV2tYF-PR1.7-hCNGB3 in CNGB3-Deficient Mice. Mol Ther 2016. [DOI: 10.1016/s1525-0016(16)33108-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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14
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Ye GJ, Budzynski E, Sonnentag P, Nork TM, Miller PE, McPherson L, Ver Hoeve JN, Smith L, Arndt T, Mandapati S, Robinson P, Calcedo R, Knop DR, Hauswirth WW, Chulay JD. Safety and Biodistribution Evaluation in CNGB3-deficient Mice of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia. HUM GENE THER CL DEV 2016. [DOI: 10.1089/hum.2015.163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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15
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Nork TM, Kim CBY, Munsey KM, Dashek RJ, Hoeve JNV. Regional choroidal blood flow and multifocal electroretinography in experimental glaucoma in rhesus macaques. Invest Ophthalmol Vis Sci 2014; 55:7786-98. [PMID: 25370515 DOI: 10.1167/iovs.14-14527] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To test a hypothesis of regional variation in the effect of experimental glaucoma on choroidal blood flow (ChBF) and retinal function. METHODS Five rhesus macaques underwent laser trabecular destruction (LTD) to induce elevated intraocular pressure (IOP). Intraocular pressures were elevated for 56 to 57 weeks. Multifocal electroretinographic (mfERG) and multifocal visual evoked cortical potential (mfVEP) testing were performed at regular intervals before and during the period of IOP elevation. At euthanasia, the IOP was manometrically controlled at 35 (experimentally glaucomatous eye) and 15 (fellow control eye) mm Hg. Fluorescent microspheres were injected into the left ventricle. Regional ChBF was determined. RESULTS All of the experimentally glaucomatous eyes exhibited supranormal first-order kernel (K1) root mean square (RMS) early portions of the mfERG waveforms and decreased amplitudes of the late waveforms. The supranormality was somewhat greater in the central macula. Second-order kernel, first slice (K2.1) RMS mfVEP response was inversely correlated (R(2) = 0.97) with axonal loss. Total ChBF was reduced in the experimentally glaucomatous eyes. The mean blood flow was 893 ± 123 and 481 ± 37 μL/min in the control and glaucomatous eyes, respectively. The ChBF showed regional variability with the greatest proportional decrement most often found in the central macula. CONCLUSIONS This is the first demonstration of globally reduced ChBF in chronic experimental glaucoma in the nonhuman primate. Both the alteration of mfERG waveform components associated with outer retinal function and the reduction in ChBF were greatest in the macula, suggesting that there may be a spatial colocalization between ChBF and some outer retinal effects in glaucoma.
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Affiliation(s)
- T Michael Nork
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
| | - Charlene B Y Kim
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
| | - Kaitlyn M Munsey
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
| | - Ryan J Dashek
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
| | - James N Ver Hoeve
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States
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Dashek RJ, Kim CBY, Rasmussen CA, Hennes-Beean EA, Ver Hoeve JN, Nork TM. Structural and functional effects of hemiretinal endodiathermy axotomy in cynomolgus macaques. Invest Ophthalmol Vis Sci 2013; 54:3479-92. [PMID: 23620427 DOI: 10.1167/iovs.12-11265] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Outer retinal injury has been well described in glaucoma. To better understand the source of this injury, we wanted to develop a reliable model of partial retinal ganglion cell (RGC) axotomy. METHODS Endodiathermy spots were placed along the inferior 180° adjacent to the optic nerve margin in the right eyes of four cynomolgus monkeys. Fluorescein angiography, spectral domain optical coherence tomography (SD-OCT), and multifocal electroretinography (mfERG) were performed at various intervals. Two animals were sacrificed at 3 months. Two animals were sacrificed at 4 months, at which time they underwent an injection of fluorescent microspheres to measure regional choroidal blood flow. Retinal immunohistochemistry for glial fibrillary acidic protein (GFAP), rhodopsin, S-cone opsin, and M/L-cone opsin were performed, as were axon counts of the optic nerves. RESULTS At 3 months, there was marked thinning of the inferior nerve fiber layer on SD-OCT. The mfERG waveforms were consistent with inner but not outer retinal injury. Greater than 95% reduction in axons was seen in the inferior optic nerves but no secondary degeneration superiorly. There was marked thinning of the nerve fiber and ganglion cell layers in the inferior retinas. However, the photoreceptor histology was similar in the axotomized and nonaxotomized areas. Regional choroidal blood flow was not affected by the axotomy. CONCLUSIONS Unlike experimental glaucoma, hemiretinal endodiathermy axotomy (HEA) of the RGCs produces no apparent anatomic, functional, or blood flow effects on the outer retina and choroid.
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Affiliation(s)
- Ryan J Dashek
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792-3220, USA
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17
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Gabelt BT, Rasmussen CA, Tektas OY, Kim CBY, Peterson JC, Nork TM, Ver Hoeve JN, Lütjen-Drecoll E, Kaufman PL. Structure/function studies and the effects of memantine in monkeys with experimental glaucoma. Invest Ophthalmol Vis Sci 2012; 53:2368-76. [PMID: 22427549 DOI: 10.1167/iovs.11-8475] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose. The scanning laser polarimetry with variable corneal compensation (GDx VCC) methodology was established and verified in monkeys with experimental glaucoma (ExpG). Terminal GDx parameters were correlated with axon counts and electrophysiologic measures. The effects of memantine on these parameters were investigated. Methods. ExpG was induced in monkeys and intraocular pressure monitored weekly. Some monkeys received memantine in their diet before and after ExpG induction (1-10 months). GDx VCC scans, stereophotographs, and multifocal visual evoked potential (mfVEP) data were collected at baseline and every 6 to 8 weeks until euthanasia. Optic nerves were prepared for axon counting and other morphologic analysis. Results. There was no difference in IOP elevation exposure between memantine-treated and no-memantine-treated monkeys. The percentage of the optic nerve area composed of connective tissue septa was significantly greater in ExpG eyes than in Fellow eyes. There was a strong positive correlation between axon counts and terminal GDx parameter measures. Animals not receiving memantine exhibited significantly lower mfVEP amplitudes in ExpG eyes compared with the ipsilateral baseline or the final value in the Fellow eye. ExpG eyes from memantine-treated animals had higher overall mean amplitudes that were not significantly different relative to the ipsilateral baseline and final amplitudes in the Fellow eye. Conclusions. The authors' studies confirm that GDx VCC can be utilized in monkey ExpG studies to detect early retinal structural changes and that these changes are highly correlated with optic nerve axon counts. These structural changes may or may not lead to central functional changes as shown by the mfVEP in response to investigational therapies.
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Affiliation(s)
- B'ann T Gabelt
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
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18
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Nork TM, Murphy CJ, Kim CBY, Ver Hoeve JN, Rasmussen CA, Miller PE, Wabers HD, Neider MW, Dubielzig RR, McCulloh RJ, Christian BJ. Functional and anatomic consequences of subretinal dosing in the cynomolgus macaque. ACTA ACUST UNITED AC 2011; 130:65-75. [PMID: 21911651 DOI: 10.1001/archophthalmol.2011.295] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To characterize functional and anatomic sequelae of a bleb induced by subretinal injection. METHODS Subretinal injections (100 μL) of balanced salt solution were placed in the superotemporal macula of 1 eye in 3 cynomolgus macaques. Fellow eyes received intravitreal injections (100 μL) of balanced salt solution. Fundus photography, ocular coherence tomography, and multifocal electroretinography were performed before and immediately after injection and again at intervals up to 3 months postinjection. Histopathologic analyses included transmission electron microscopy and immunohistochemistry for glial fibrillary acidic protein, rhodopsin, M/L-cone opsin, and S-cone opsin. RESULTS Retinas were reattached by 2 days postinjection (seen by ocular coherence tomography). Multifocal electroretinography waveforms were suppressed post-subretinal injection within the subretinal injection bleb and, surprisingly, also in regions far peripheral to this area. Multifocal electroretinography amplitudes were nearly completely recovered by 90 days. The spectral-domain ocular coherence tomography inner segment-outer segment line had decreased reflectivity at 92 days. Glial fibrillary acidic protein and S-cone opsin staining were unaffected. Rhodopsin and M/L-cone opsins were partially displaced into the inner segments. Transmission electron microscopy revealed disorganization of the outer segment rod (but not cone) discs. At all postinjection intervals, eyes with intravitreal injection were similar to baseline. CONCLUSIONS Subretinal injection is a promising route for drug delivery to the eye. Three months post-subretinal injection, retinal function was nearly recovered, although reorganization of the outer segment rod disc remained disrupted. Understanding the functional and anatomic effects of subretinal injection is important for interpretation of the effects of compounds delivered to the subretinal space. CLINICAL RELEVANCE Subretinal injection is a new potential route for drug delivery to the eye. Separating drug effects from the procedural effects is critical.
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Affiliation(s)
- T Michael Nork
- Comparative Ophthalmic Research Laboratories, University of Wisconsin, USA.
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19
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Altaweel MM, Hanzlik RP, Ver Hoeve JN, Eells J, Zhang B. Ocular and systemic safety evaluation of calcium formate as a dietary supplement. J Ocul Pharmacol Ther 2009; 25:223-30. [PMID: 19456257 DOI: 10.1089/jop.2008.0128] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The objective of this study was to perform a preliminary evaluation of the ocular and systemic safety of calcium formate, a dietary calcium supplement for prevention and management of osteoporosis. Although formate is an endogenous product of metabolism, high concentrations are associated with toxicity during methanol overdose. METHODS In this prospective clinical trial, 12 healthy women ingested calcium formate (1,300 mg) three times a day for 14 days. Study evaluations included physical and ocular examination, extensive laboratory testing, serum calcium and formate levels, Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity, color vision, visual fields, visual evoked potential (VEP), and full-field, pattern, and multifocal electroretinograms (MERG). RESULTS The mean baseline serum level of formate was 0.572 +/- 0.06 mM. Peak serum levels and final serum formate did not differ significantly from baseline. The final concentration was 0.582 +/- 0.091 mM. Accumulation of serum formate did not occur. There was also no evidence of toxicity with calcium formate ingestion. All examinations and tests remained normal, including optic nerve and retinal function. Three subjects had mild transient symptoms attributable to any calcium formulation. CONCLUSIONS Calcium formate is highly bioavailable and well-tolerated. Serum formate remained at basal levels and did not accumulate with repeated dosing. Systemic and ocular safety was demonstrated by objective testing. Given its high oral bioavailability, calcium formate may be a good choice for calcium supplementation in the prevention and management of osteoporosis. Further study will be needed to evaluate its long-term safety in a larger group of subjects representing more varied age, health, dietary, and nutritional status.
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Affiliation(s)
- Michael M Altaweel
- Department of Ophthalmology and Visual Science, School of Medicine and Public Health, University of Wisconsin-Madison, WI, USA
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20
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Nickells RW, Schlamp CL, Li Y, Kaufman PL, Heatley G, Peterson JC, Faha B, Ver Hoeve JN. Surgical lowering of elevated intraocular pressure in monkeys prevents progression of glaucomatous disease. Exp Eye Res 2006; 84:729-36. [PMID: 17291496 PMCID: PMC1863170 DOI: 10.1016/j.exer.2006.12.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 12/08/2006] [Accepted: 12/13/2006] [Indexed: 11/28/2022]
Abstract
Recent reports from large clinical trials have clearly demonstrated that lowering intraocular pressure (IOP) in persons with ocular hypertension has a beneficial effect on reducing the progression of glaucomatous disease. Few studies of this effect have been conducted in controlled laboratory settings, however, none have been conducted using non-human primates, the model of experimental glaucoma considered most similar to the human disease. Using data collected retrospectively from a trabeculectomy study using 16 cynomolgous monkeys with experimental ocular hypertension, we evaluated both the threshold of elevated IOP required to cause clinically observable damage to the optic nerve head and also if lowering IOP below this threshold prevents further damage. An index of the level of elevated IOP experienced by experimental eyes (the Pressure Insult) was calculated as the slope of the difference in cumulative IOP between experimental and control eyes during four intervals of time over the course of the experiment, while damage to the optic nerve head was evaluated by measuring the Cup:Disc ratio for each eye from stereoscopic photographs taken at the end of each interval. An increase in the Cup:Disc ratio was significantly associated with both the maximum IOP obtained in the experimental eye during each interval (r=0.573, P<0.001) and the Pressure Insult (r=0.496, P<0.001). Pressure Insult values less than 11 mm Hg Days/Day were not associated with glaucomatous damage in monkey eyes, whereas values greater than 11 showed a significant correlation with increasing Cup:Disc ratios (P<0.001). Trabeculectomy to reduce the Pressure Insult below 11 was correlated with an attenuation of the rate of progression of the Cup:Disc ratio in eyes that had exhibited damage before surgery. These results contribute further to our understanding of this model of experimental glaucoma by demonstrating a threshold at which IOP needs to be elevated to stimulate damage, while also providing corroborating evidence that lowering IOP in ocular hypertensive monkeys can attenuate the progression of glaucomatous disease.
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Affiliation(s)
- Robert W Nickells
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53706, USA.
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Maertz NA, Kim CBY, Nork TM, Levin LA, Lucarelli MJ, Kaufman PL, Ver Hoeve JN. Multifocal visual evoked potentials in the anesthetized non-human primate. Curr Eye Res 2006; 31:885-93. [PMID: 17050280 DOI: 10.1080/02713680600899648] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To evaluate monkey multifocal visual evoked cortical potentials (mfVEPs) recorded from central and peripheral fields for reliability and isolation from electroretinographic (ERG) activity. METHODS The mfVEP stimulus consisted of a 7-element hexagonal array that subtended 80 degrees of the central visual field. Recordings were made under intravenous pentobarbital sodium (15 mg/kg) anesthesia. Two monkeys with absent optic nerve and ganglion cell function after combined unilateral optic nerve transection and experimental ocular hypertension (ONT/OHT) were followed longitudinally. In a second study, 16 ophthalmologically normal monkeys were tested once. RESULTS Testing of the non-transected eye in two transected animals revealed robust first- and second-order kernel, first slice (K1 and K2.1) mfVEPs. Stimulation of the transected eye revealed no contamination of the mfVEP from the concurrently recorded multifocal ERGs. There was complete separation of the root-mean-square (RMS) mfVEP amplitudes from the transected and the fellow eyes tested repeatedly across a 4- to 17- month period. The largest amplitude mfVEP was generated by the central element; however, mfVEPs were recorded from outside the central 20 degrees element. The 16 normal animals showed waveforms similar to the normal eyes of the ONT/OHT animals both in shape and distribution throughout the visual field. A scalar-product measure showed both K1 and K2.1 mfVEPs from central and some peripheral elements were statistically distinct from noise. CONCLUSIONS mfVEPs can be reliably recorded from non-human primates anesthetized with pentobarbital. Under the recording conditions described, mfVEPs are not contaminated by ERG activity. mfVEPs may be useful in animal models of diseases that differentially affect macular and peripheral visual field responsiveness.
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Affiliation(s)
- Nathan A Maertz
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792-3220, USA
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22
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Nork TM, Kim CBY, Shanmuganayagam D, Van Lysel MS, Ver Hoeve JN, Folts JD. Measurement of Regional Choroidal Blood Flow in Rabbits and Monkeys Using Fluorescent Microspheres. ACTA ACUST UNITED AC 2006; 124:860-8. [PMID: 16769840 DOI: 10.1001/archopht.124.6.860] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To develop a quantitative measure of regional variation in choroidal blood flow (ChBF). METHODS Five million 15-microm fluorescent microspheres were injected into the left ventricles of 4 rabbits and 3 monkeys. The fixed globes were bleached, flat mounted, and photomicrographed. After image analysis to locate each microsphere, regional densities and blood flow were determined. RESULTS Regional variation in ChBF was clearly evident. In the rabbit, a high density of spheres was seen in the visual streak. This was surrounded by a middle peripheral area of low sphere density and a far peripheral region of moderately high density. In the monkeys, sphere density was markedly greater in the macula compared with the periphery. Contour plots produced lines of constant flow that were oval and extended farther nasally than temporally in the monkeys. The ratio of central to peripheral ChBF was much greater in the monkeys than in the rabbits. CONCLUSION Quantitative assessment of regional ChBF can be performed using a modification of the fluorescent microsphere impaction method. CLINICAL RELEVANCE This method of determining regional ChBF will be useful for studying the vascular effects of pharmacologic agents and for characterizing animal models of human disease involving the outer retina.
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Affiliation(s)
- T Michael Nork
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison 53792-3220, USA.
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Abstract
The purpose of this study is to ascertain whether inherent differences exist in the retinal function of two macaque species that are commonly used in experimental glaucoma investigations. We quantified and compared multifocal electroretinograms (mfERGs) from ocularly normal cynomolgus (n = 36) and rhesus (n = 18) monkeys. The stimulus array consisted of 103 equal-sized hexagonal elements, which subtended +/-44 degrees about the central visual axis. Mean luminance of the display was 100 cd/m2. The firstorder kernel (K1) and second-order (first slice) kernel (K2) of the mfERG were averaged into 4 rings radiating from the foveal element, and represented the central 56 degrees of visual field. Fifteen and 30-element segments were used for K1 and K2 quadrant and hemiretinal response determinations, respectively. Response measures for the rings, quadrants, and hemiretinae included K1 amplitude and implicit time, and K1 and K2 oscillatory potentials (OPs) and response amplitude root mean square (RMS). Species, gender, and retinotopic differences were assessed with repeated measures analysis of variance (split plot design). K1 amplitudes of the N1 waves, K1 and K2 OPs and K2 amplitude RMS for the ring, quadrant, and hemiretinal mfERG waveforms were larger in rhesus than in cynomolgus monkeys. Rhesus males (as compared to rhesus females) and cynomolgus females (as compared to cynomolgus males) exhibited larger amplitudes and less delayed implicit times in the central retina. These results demonstrate that species-specific differences in retinal function are evident in cynomolgus and rhesus monkeys. There also were gender-associated differences that varied across species. Thus, investigators should exercise caution when data from species or gender are combined.
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Affiliation(s)
- Charlene B Y Kim
- Department of Ophthalmology and Visual Sciences, University of Wisconsin Medical School, Madison, WI, USA.
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Stevenson MB, Ver Hoeve JN, Roach MA, Leavitt LA. The beginning of conversation: Early patterns of mother-infant vocal responsiveness. Infant Behav Dev 1986. [DOI: 10.1016/0163-6383(86)90016-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Stevenson MB, Roach MA, Ver Hoeve JN. Behavioral contingencies during feeding of 8-month-old low birthweight infants. Infant Behav Dev 1984. [DOI: 10.1016/s0163-6383(84)80411-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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