title: Virus-mediated EpoR76E gene therapy preserves vision in a glaucoma model by modulating neuroinflammation and decreasing oxidative stress.
abstract: BACKGROUND
  Glaucoma is a complex neurodegeneration and a leading cause of blindness worldwide. Current therapeutic strategies, which are all directed towards lowering the intraocular pressure (IOP), do not stop progression of the disease. We have demonstrated that recombinant adeno-associated virus (rAAV) gene delivery of a form of erythropoietin with attenuated erythropoietic activity (EpoR76E) can preserve retinal ganglion cells, their axons, and vision without decreasing IOP. The goal of this study was to determine if modulation of neuroinflammation or oxidative stress played a role in the neuroprotective activity of EPO.R76E.
  
  
  METHODS
  Five-month-old DBA/2J mice were treated with either rAAV.EpoR76E or a control vector and collected at 8 months of age. Neuroprotection was assessed by quantification of axon transport and visual evoked potentials. Microglia number and morphology and cytokine and chemokine levels were quantified. Message levels of oxidative stress-related proteins were assessed.
  
  
  RESULTS
  Axon transport and visual evoked potentials were preserved in rAAV.EpoR76E-treated mice. The number of microglia was decreased in retinas from 8-month-old rAAV.EpoR76E-treated mice, but proliferation was unaffected. The blood-retina barrier was also unaffected by treatment. Levels of some pro-inflammatory cytokines were decreased in retinas from rAAV.EpoR76E-treated mice including IL-1, IL-12, IL-13, IL-17, CCL4, and CCL5. TNFα messenger RNA (mRNA) was increased in retinas from 8-month-old mice compared to 3-month-old controls regardless of treatment. Expression of several antioxidant proteins was increased in retinas of rAAV.EpoR76E-treated 8-month-old mice.
  
  
  CONCLUSIONS
  Treatment with rAAV.EpoR76E preserves vision in the DBA/2J model of glaucoma at least in part by decreasing infiltration of peripheral immune cells, modulating microglial reactivity, and decreasing oxidative stress.
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA.|Vanderbilt Brain Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Hines-Beard
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA.|Vanderbilt Brain Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA.
authors.forename: Wesley S
authors.initials: WS
authors.lastname: Bond
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA.|Vanderbilt Brain Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA.
authors.forename: Jon R
authors.initials: JR
authors.lastname: Backstrom
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA. tonia.rex@vanderbilt.edu.|Vanderbilt Brain Institute, Vanderbilt University, 11435 MRB IV, 2213 Garland Avenue, Nashville, TN, 37232, USA. tonia.rex@vanderbilt.edu.
authors.forename: Tonia S
authors.initials: TS
authors.lastname: Rex
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins; D002772:Cholera Toxin / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D000229:Dependovirus / Q000235:genetics; D004195:Disease Models, Animal; D004921:Erythropoietin / Q000235:genetics / Q000627:therapeutic use*; D005074:Evoked Potentials, Visual / Q000502:physiology; D005451:Fluorescein Angiography; D005786:Gene Expression Regulation / Q000502:physiology; D015316:Genetic Therapy / Q000379:methods*; D005901:Glaucoma / Q000150:complications* / Q000628:therapy*; D019394:Ki-67 Antigen / Q000378:metabolism; D051379:Mice; D008811:Mice, Inbred DBA; D008840:Microfilament Proteins; D017628:Microglia / Q000473:pathology; D018384:Oxidative Stress / Q000502:physiology*; D010775:Photic Stimulation; D012160:Retina / Q000473:pathology; D014161:Transduction, Genetic
chemical_list: C491049:Aif1 protein, mouse; D002135:Calcium-Binding Proteins; D016207:Cytokines; C554270:EPO protein, human; D019394:Ki-67 Antigen; D008840:Microfilament Proteins; D004921:Erythropoietin; D002772:Cholera Toxin