title: A chick model of retinal detachment: cone rich and novel.
abstract: BACKGROUND
  Development of retinal detachment models in small animals can be difficult and expensive. Here we create and characterize a novel, cone-rich retinal detachment (RD) model in the chick.
  
  
  RESULTS
  Retinal detachments were created in chicks between postnatal days 7 and 21 by subretinal injections of either saline (SA) or hyaluronic acid (HA). Injections were performed through a dilated pupil with observation via surgical microscope, using the fellow eye as a control. Immunohistochemical analyses were performed at days 1, 3, 7, 10 and 14 after retinal detachment to evaluate the cellular responses of photoreceptors, Müller glia, microglia and nonastrocytic inner retinal glia (NIRG). Cell proliferation was detected with bromodeoxyuridine (BrdU)-incorporation and by the expression of proliferating cell nuclear antigen (PCNA). Cell death was detected with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). As in mammalian models of RD, there is shortening of photoreceptor outer segments and mis-trafficking of photoreceptor opsins in areas of RD. Photoreceptor cell death was maximal 1 day after RD, but continued until 14 days after RD. Müller glia up-regulated glial fibriliary acidic protein (GFAP), proliferated, showed interkinetic nuclear migration, and migrated to the subretinal space in areas of detachment. Microglia became reactive; they up-regulated CD45, acquired amoeboid morphology, and migrated toward outer retina in areas of RD. Reactive NIRG cells accumulated in detached areas.
  
  
  CONCLUSIONS
  Subretinal injections of SA or HA in the chick eye successfully produced retinal detachments and cellular responses similar to those seen in standard mammalian models. Given the relatively large eye size, and considering the low cost, the chick model of RD offers advantages for high-throughput studies.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Havener Eye Institute, The Ohio State University, Columbus, Ohio, United States of America. Colleen.Cebulla@osumc.edu
authors.forename: Colleen M
authors.initials: CM
authors.lastname: Cebulla
authors.forename: Chris P
authors.initials: CP
authors.lastname: Zelinka
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Scott
authors.forename: Martin
authors.initials: M
authors.lastname: Lubow
authors.forename: Amanda
authors.initials: A
authors.lastname: Bingham
authors.forename: Stephen
authors.initials: S
authors.lastname: Rasiah
authors.forename: Ashraf M
authors.initials: AM
authors.lastname: Mahmoud
authors.forename: Andy J
authors.initials: AJ
authors.lastname: Fischer
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology; D016923:Cell Death; D049109:Cell Proliferation; D002645:Chickens; D004195:Disease Models, Animal; D006820:Hyaluronic Acid; D009457:Neuroglia / Q000473:pathology; D055355:Opsins / Q000378:metabolism; D021381:Protein Transport; D017949:Retinal Cone Photoreceptor Cells / Q000378:metabolism / Q000473:pathology*; D012163:Retinal Detachment / Q000378:metabolism / Q000473:pathology*; D015854:Up-Regulation
chemical_list: D055355:Opsins; D006820:Hyaluronic Acid