title: Alteration of tear cytokine balance by eye closure: analysis by multicytokine assay.
abstract: OBJECTIVE
  To study the effects of eye closure on the balance of tear cytokines.
  
  
  METHODS
  A total of 17 healthy volunteers with normal eyes were recruited. Tears (10 microl) were collected by capillary outflow at 09:00. The right eyes were closed with cotton bandages for 3 h, then tears were collected from each eye separately. The concentrations of inflammatory cytokines, interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12p70, and tumor necrosis factor (TNF)-alpha were measured by cytometric bead array.
  
  
  RESULTS
  Although the concentration of each cytokine varied between eyes, the increasing ratio for 3 h showed a similar pattern in each cytokine. IL-1beta, IL-6, IL-10, IL-12p70, and TNF-alpha increased and IL-8 decreased in normal eyes. After eye closure, the increase of IL-10 significantly diminished (P=0.037); however, the other cytokines were not affected.
  
  
  CONCLUSIONS
  Eye closure decreased the concentration of IL-10 in tears, which might cause a potentially pro-inflammatory status of the ocular surface.
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Kagoshima University Graduate School of Medicine and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8520, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Uchino
authors.forename: Shozo
authors.initials: S
authors.lastname: Sonoda
authors.forename: Kumiko
authors.initials: K
authors.lastname: Nakao
authors.forename: Taiji
authors.initials: T
authors.lastname: Sakamoto
mesh_terms: D000328:Adult; D001767:Blinking / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay; D005136:Eye Proteins / Q000378:metabolism*; D005260:Female; D006801:Humans; D007378:Interleukins / Q000378:metabolism*; D008297:Male; D013666:Tears / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: D005136:Eye Proteins; D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; C042434:tear proteins