title: Immunocytochemical and ultrastructural evidence of glial cells and hyalocytes in internal limiting membrane specimens of idiopathic macular holes.
abstract: OBJECTIVE
  To provide new information on epiretinal cell proliferation and the cells' origin in idiopathic macular holes and to overcome the effects of embedding and sectioning preparation procedures on cell-distribution patterns.
  
  
  METHODS
  Interference and phase-contrast microscopy, immunocytochemistry, and scanning and transmission electron microscopy were performed on surgically excised whole-mounted internal limiting membrane (ILM) specimens removed from 60 eyes with idiopathic macular holes. Cell distribution and cell morphology were correlated with immunocytochemical staining characteristics. Twelve cell type-specific antibodies were used to detect glial cells, hyalocytes, retinal pigment epithelial cells, retinal ganglion cells, and immune cells. Cell viability was analyzed.
  
  
  RESULTS
  Epiretinal cell proliferation was found in all ILM specimens, irrespective of the stage of the macular hole. Cell density showed a broad variety. Immunocytochemistry frequently revealed simultaneous expression of GFAP/CD45, GFAP/CD64, GFAP/CD68, GFAP/CRALBP, and GFAP/CD90. Some cells presented with intracellular contractile filaments (anti-αSMA); others were not immunoreactive to any antibody examined. The percentage of viable cells showed a broad variety with a mean of 73% (SD 29%). Electron microscopy demonstrated glial cells, hyalocytes, and myofibroblast-like cells.
  
  
  CONCLUSIONS
  The presence of epiretinal cells at the ILM in all macular hole stages strongly suggests a substantial involvement of cell migration and proliferation in the course of macular hole development. Glial cells and hyalocytes play the predominant role in epiretinal cell proliferation. Given the co-expression of glial cell and hyalocyte markers, transdifferentiation of epiretinal cells needs further elucidation, especially with respect to αSMA-positive cells leading to traction at the vitreoretinal interface.
authors: Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. ricarda.schumann@med.uni-muenchen.de
authors: Ricarda G
authors: RG
authors: Schumann
authors: Kirsten H
authors: KH
authors: Eibl
authors: Fei
authors: F
authors: Zhao
authors: Martin
authors: M
authors: Scheerbaum
authors: Renate
authors: R
authors: Scheler
authors: Markus M
authors: MM
authors: Schaumberger
authors: Helga
authors: H
authors: Wehnes
authors: Axel K
authors: AK
authors: Walch
authors: Christos
authors: C
authors: Haritoglou
authors: Anselm
authors: A
authors: Kampik
authors: Arnd
authors: A
authors: Gandorfer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001485:Basement Membrane / Q000378:metabolism / Q000648:ultrastructure*; D015415:Biomarkers / Q000378:metabolism; D002452:Cell Count; D019070:Cell Lineage; D002465:Cell Movement; D049109:Cell Proliferation; D002470:Cell Survival; D019773:Epiretinal Membrane / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D008857:Microscopy, Interference; D008858:Microscopy, Phase-Contrast; D008875:Middle Aged; D009457:Neuroglia / Q000378:metabolism / Q000648:ultrastructure*; D012165:Retinal Ganglion Cells / Q000378:metabolism / Q000648:ultrastructure; D012167:Retinal Perforations / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D055213:Retinal Pigment Epithelium / Q000378:metabolism / Q000648:ultrastructure; D014821:Vitrectomy; D014822:Vitreous Body / Q000378:metabolism / Q000648:ultrastructure*
chemical_list: D015415:Biomarkers