Interleukin-6 levels in the conjunctival epithelium of patients with dry eye disease treated with cyclosporine ophthalmic emulsion

Cornea. 2000 Jul;19(4):492-6. doi: 10.1097/00003226-200007000-00018.


Purpose: To evaluate interleukin-6 (IL-6) levels in the conjunctival epithelium of patients with moderate to severe dry eye disease before and after treatment with cyclosporin A ophthalmic emulsion (CsA) or its vehicle.

Methods: Conjunctival cytology specimens were obtained from a subset of patients enrolled in a 6-month randomized, double-masked clinical trial of the efficacy and safety of topical CsA at baseline and after 3 and 6 months of B.I.D. treatment with 0.05% cyclosporine emulsion (n = 13), 0.1% cyclosporine emulsion (n = 8), or vehicle (n = 10). RNA was extracted and a competitive reverse transcriptase polymerase chain reaction (RT-PCR) was used to evaluate the levels of mRNA encoding the inflammatory cytokine IL-6 and a housekeeping gene, G3PDH. Levels of IL-6 and G3PDH were measured and compared.

Results: There was no change from baseline in the level of G3PDH after 3 or 6 months in any group. IL-6 normalized for G3PDH (IL-6/G3PDH ratio) was not different from baseline at 3 months but showed a significant decrease from baseline in the group treated with 0.05% CsA (p = 0.048) at 6 months. No significant between-group differences were noted and no correlation was observed between the change in IL-6/G3PDH and corneal fluorescein staining.

Conclusions: This preliminary, small-cohort study showed a decrease in IL-6 in the conjunctival epithelium of moderate to severe dry eye patients treated with 0.05% CsA for 6 months. The observed decrease suggests that dry eye disease involves immune-mediated inflammatory processes that may be decreased by treatment with topical ophthalmic cyclosporine.

Publication types

  • Clinical Trial
  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Topical
  • Biomarkers
  • Conjunctiva / metabolism*
  • Conjunctiva / pathology
  • Cyclosporine / therapeutic use*
  • DNA Primers / chemistry
  • Double-Blind Method
  • Dry Eye Syndromes / drug therapy*
  • Dry Eye Syndromes / metabolism
  • Dry Eye Syndromes / pathology
  • Emulsions
  • Epithelium / metabolism*
  • Epithelium / pathology
  • Glyceraldehyde-3-Phosphate Dehydrogenases / metabolism
  • Humans
  • Immunosuppressive Agents / therapeutic use*
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism*
  • Prospective Studies
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction


  • Biomarkers
  • DNA Primers
  • Emulsions
  • Immunosuppressive Agents
  • Interleukin-6
  • RNA, Messenger
  • Cyclosporine
  • Glyceraldehyde-3-Phosphate Dehydrogenases