title: Immunohistochemical Characterization of the Ectopic Epithelium Devoid of Goblet Cells From a Posttraumatic Iris Cyst Causing Mucogenic Glaucoma.
abstract: OBJECTIVE
  Mucogenic glaucoma is an unusual form of secondary open-angle glaucoma caused by intracameral ectopic mucus-producing epithelium. To date, only 3 cases have been described in detail. Numerous goblet cells in the specimens indicated a possible conjunctival origin. We immunohistochemically characterized the implanted epithelium from an iris cyst responsible for mucogenic glaucoma.
  
  
  METHODS
  A series of immunostaining analyses were performed on a sector-iridectomy specimen derived from an eye with mucogenic glaucoma and a history of limbal penetrating injury. An iris cyst was present in the inferonasal quadrant of the right eye of a 58-year-old man. The anterior chamber was filled with hazy, translucent material, and the chamber angle was gonioscopically open. The cyst was resected due to medically uncontrollable high intraocular pressure.
  
  
  RESULTS
  The ectopic epithelium was mostly positive for CK19, a corneal and conjunctival epithelial marker. Negative staining for MUC5AC, a secretory mucin, and positive staining for MUC1, a membrane-bound mucin, corroborated the absence of goblet cells. Ectopic epithelial cells were abundantly positive for CK15, a limbal basal cell marker, but there was patchy immunostaining of CK13, a conjunctival epithelial marker, and sparse labeling with CK12, a corneal epithelial marker. Immunostaining patterns of CK15, CK13, and CK12 were nearly mutually exclusive.
  
  
  CONCLUSIONS
  The ectopic epithelium of an iris cyst causing mucogenic glaucoma was most likely to originate from limbal basal cells, which showed dual direction of differentiation toward both the conjunctival and corneal epithelia. The membrane-bound mucin may have caused mucogenic glaucoma in the absence of goblet cells.
authors.affiliation: *Department of Ophthalmology and Visual Science, Kanazawa University Graduate School of Medical Science, Kanazawa †Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima ‡Department of Frontier Medical Science and Technology for Ophthalmology Kyoto Prefectural University of Medicine, Kyoto §Department of Ophthalmology, Kansai Medical University, Hirakata, Japan.
authors.forename: Haruka
authors.initials: H
authors.lastname: Wakae
authors.forename: Tomomi
authors.initials: T
authors.lastname: Higashide
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsuneyama
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakamura
authors.forename: Kanji
authors.initials: K
authors.lastname: Takahashi
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Sugiyama
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D002828:Choristoma / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism*; D065306:Corneal Injuries / Q000209:etiology / Q000378:metabolism*; D003560:Cysts / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism*; D019573:Epithelium, Corneal; D015807:Eye Injuries, Penetrating / Q000209:etiology / Q000378:metabolism; D005902:Glaucoma, Open-Angle / Q000175:diagnosis / Q000209:etiology*; D020397:Goblet Cells / Q000473:pathology*; D006068:Gonioscopy; D006801:Humans; D007124:Immunoenzyme Techniques; D007499:Iris Diseases / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism*; D053539:Keratin-19 / Q000378:metabolism; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D055271:Mucin 5AC / Q000378:metabolism; D018396:Mucin-1 / Q000378:metabolism; D009093:Mucus / Q000378:metabolism; D013508:Ophthalmologic Surgical Procedures
chemical_list: D015415:Biomarkers; D053539:Keratin-19; C060192:MUC1 protein, human; C524678:MUC5AC protein, human; D055271:Mucin 5AC; D018396:Mucin-1