title: Changes in corneal epithelial layer inflammatory cells in aqueous tear-deficient dry eye.
abstract: OBJECTIVE
  To investigate the morphology, distribution, and density of inflammatory cells in the corneal epithelium of aqueous tear-deficient dry eye.
  
  
  METHODS
  Thirty-two patients with non-Sjögren's syndrome (NSS) dry eye, 14 patients with Sjögren's syndrome (SS) dry eye, and 33 healthy volunteers were studied. In vivo laser scanning confocal microscopy was used to investigate both Langerhans cell (LCs) and leukocyte distribution and density in the peripheral and central corneal epithelium. LC morphology was also evaluated. Multifactor regression analysis assessed whether there is a correlation between clinical manifestations and inflammatory cell densities.
  
  
  RESULTS
  LCs were present in both central (34.9 +/- 5.7 cells/mm(2)) and peripheral (90.7 +/- 8.2 cells/mm(2)) parts of the normal corneal epithelium. Moreover, LC density increased dramatically in the central corneal epithelium in patients with NSS (89.8 +/- 10.8 cells/mm(2)) and SS (127.9 +/- 23.7 cells/mm(2)). The ratio of LCs with obvious processes was much higher in patients with dry eye than in healthy volunteers. LC density also increased in peripheral corneal epithelium in patients with SS, but not in those with NSS. Leukocyte density in normal corneal epithelium was very low, whereas it increased in the central corneal epithelium (4.6 +/- 1.0 cells/mm(2)) in NSS and in both central (49.0 +/- 12.9 cells/mm(2)) and peripheral (84.2 +/- 36.8 cells/mm(2)) corneal epithelium in SS. Densities of LCs and leukocytes showed significant correlation with the severity found in clinical evaluation.
  
  
  CONCLUSIONS
  The LC and leukocyte changes in the corneal epithelium suggest their involvement in aqueous tear-deficient dry eye pathophysiology. In vivo dynamic assessment of central corneal inflammatory cell density may serve as an indicator of dry eye severity and provide new insight for dry eye treatment.
authors.affiliation: Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Lin
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Nuo
authors.initials: N
authors.lastname: Dong
authors.forename: Wensheng
authors.initials: W
authors.lastname: Chen
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Lelei
authors.initials: L
authors.lastname: Chen
authors.forename: Hongxia
authors.initials: H
authors.lastname: Yuan
authors.forename: Zhixin
authors.initials: Z
authors.lastname: Geng
authors.forename: Zuguo
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002452:Cell Count; D015352:Dry Eye Syndromes / Q000378:metabolism / Q000473:pathology*; D019573:Epithelium, Corneal / Q000473:pathology*; D005260:Female; D006801:Humans; D007801:Langerhans Cells / Q000473:pathology*; D007962:Leukocytes / Q000473:pathology*; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D013666:Tears / Q000378:metabolism*; D055815:Young Adult