Abstract
Purpose: :
To investigate the expression of monokine induced by interferon-γ (MIG), interferon-γ-inducible protein 10 (IP-10), and interferone-inducible T-cell alpha chemoattactant (I-TAC), and CXCR3 in the tear film and ocular surface of patients with dry eye syndrome.
Methods: :
Thirty-four patients with dry eye (16 patients with Sjögren’s syndrome and 17 patients with non-Sjögren’s syndrome) and 15 control subjects were recruited. The protein concentrations of MIG, IP-10, and I-TAC in tears were measured by enzyme-linked immunosorbent assay. The correlation between the chemokine levels and tear film parameters was analyzed. Expression of CXCR3, MIG, IP-10, and I-TAC was evaluated by immunohistochemistry in conjuntival impression cytology and biopsy specimens.
Results: :
The concentrations of MIG, IP-10, and I-TAC were 1,473±1,173, 22,546±8,498, and 717±377 pg/mL in dry eye patients and 276±301 (P=0.03), 19,032±5,937 (P=0.14), and 444±119 (P<0.01) pg/mL in the controls. The concentrations were significantly increased in Sjögren’s syndrome patients compared with non- Sjögren’s syndrome patients (P<0.05). IP-10 levels correlated significantly with basal tear secretion, and I-TAC levels correlated significantly with basal tear secretion, tear clearance rate, keratoepitheliopathy, and goblet cell density. Staining for MIG, IP-10, I-TAC, CXCR3 increased in the conjunctiva of dry eye patients, especially in Sjögren’s syndrome patients.
Conclusions: :
Expression of MIG, IP-10, I-TAC, and CXCR3 increases in the tear film and ocular surface of patients with dry eye syndrome. The chemokine levels are associated with disease severity and correlate with various tear film and ocular surface parameters.
Keywords: cytokines/chemokines • conjunctiva