title: Accumulation of secretory vesicles in the lacrimal gland epithelia is related to non-Sjögren's type dry eye in visual display terminal users.
abstract: Previous observations in a rat model of a non-Sjögren's syndrome (non-SS) type of dry eye seen in users of visual display terminals (VDT) indicated that secretory vesicle (SV) accumulation in the lacrimal gland epithelia contributes to the condition. Here, to examine this possibility in humans, we compared the lacrimal gland histology and percent SV area in the cytoplasm of acinar epithelial cells using light microscopy and transmission electron microscopy, in patients with VDT work-related non-SS dry-eye (VDT group), SS-induced dry-eye, and autopsied normal controls. In addition, the VAMP8 (vesicle-associated membrane protein 8, an exocrine-pathway molecule) and Rab3D (mature vesicle marker) were histochemically examined in lacrimal gland tissue sections. The lacrimal gland acini were larger in the VDT group than in the SS group, and the percent SV area was significantly higher in the VDT group than in the normal controls (P = 0.021) or SS group (P = 0.004). Immunostaining revealed abnormal distributions of VAMP8 in the VDT and SS groups. Rab3D was more strongly expressed in the cytoplasm of acinar epithelial cells in the VDT group than in that of normal controls. The duration of VDT use was significantly longer in the VDT group than in the other groups. These findings suggest that excessive SV accumulation in the acinar epithelia may contribute to the reduced tear secretion in VDT users.
authors.affiliation: Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Mizuka
authors.initials: M
authors.lastname: Kamoi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Shigeru
authors.initials: S
authors.lastname: Nakamura
authors.forename: Murat
authors.initials: M
authors.lastname: Dogru
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Nagai
authors.forename: Hiroto
authors.initials: H
authors.lastname: Obata
authors.forename: Masataka
authors.initials: M
authors.lastname: Ito
authors.forename: Minako
authors.initials: M
authors.lastname: Kaido
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kawakita
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Okada
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kawakami
authors.forename: Shigeto
authors.initials: S
authors.lastname: Shimmura
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D016288:Computer Terminals; D003593:Cytoplasm / Q000378:metabolism / Q000473:pathology*; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology*; D004848:Epithelium / Q000378:metabolism / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D007765:Lacrimal Apparatus / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D050683:R-SNARE Proteins / Q000235:genetics / Q000378:metabolism; D022142:Secretory Vesicles / Q000378:metabolism / Q000473:pathology*; D012859:Sjogren's Syndrome / Q000503:physiopathology; D014985:Xerophthalmia / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D020692:rab3 GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D050683:R-SNARE Proteins; C112938:VAMP8 protein, human; C492134:RAB3D protein, human; D020692:rab3 GTP-Binding Proteins