Flow cytometric analysis of inflammatory markers in conjunctival epithelial cells of patients with dry eyes

PURPOSE. To investigate in impression cytology (IC) specimens the expressio n of inflammatory and apoptosis-related markers by conjunctival epithelial cells from patients with dry eye as a rationale for treatment with topical cyclosporine. METHODS. Immunologic anomalies were identified at baseline, before treatmen t with the masked medication, in a homogeneous series of patients with dry eye syndrome, who were enrolled in a large European multicenter clinical tr ial (Cyclosporin A Dry Eye Study; Allergen, Irvine, CA). IC specimens were collected in 243 patients with moderate to severe keratoconjunctivitis sicc a (KCS), with or without Sjogren's syndrome (SS). Fifty normal subjects wer e separately examined to provide normal control values. Specimens were anal yzed in a masked manner by flow cytometry, using antibodies directed to mar kers of the immune system and/or apoptotic pathway: HLA DR, CD40, CD40 liga nd, Fas, and APO2.7. Levels of expression were quantified. and results were compared with those obtained in the 50 normal patients. RESULTS. One hundred sixty-nine specimens were successfully interpreted at baseline. including 41% from patients with SS. A highly significant increas e of HLA DR expression by conjunctival cells was found in KCS-affected eyes compared with normal eyes, which did not express this marker or did so ver y weakly. HLA DR expression in eyes with SS was significantly higher than i n KCS-affected eves without SS. Fas and APO2.7 were found at low levels in all normal and KCS-affected eyes. CD40 and CD40 ligand expressions were sig nificantly increased in eyes with KCS compared with normal eyes. HLA DR, CD 40 and Fas were found at significantly higher levels in the SS group than i n the non-SS group. CONCLUSIONS. Conjunctival cells from patients with dry eye with moderate to severe KCS, with or without SS, overexpress inflammatory and apoptosis-rel ated markers. Whether inflammation is a primary phenomenon in KCS or is the consequence of repetitive abrasion of the ocular surface after tear film d eficiency remains to be determined. These data, nevertheless, support the u se of immunomodulatory and/or anti-inflammatory drugs in the treatment of p atients with KCS.