Quantitative analysis of lacrimal gland function, apoptotic figures, Fas and Fas ligand expression of lacrimal glands in dry eye patients

The purpose of our study was to examine the correlation between the lacrimal gland function and apoptotic figure, Fas and Fas ligand (FasL) expression in the lacrimal gland. A total of 15 dry eye patients (nine Sjögren's syndrome and six non-Sjögren's syndrome-type dry eye) were recruited for the study. Lacrimal function was evaluated by Schirmer tests 1 and 2. Lacrimal gland biopsies were performed and sections were analyzed by immunohistochemistry using APO2·7, an antibody to Fas and FasL. Quantitative analysis of fluorescein staining was performed by a scanning laser microscopy. Schirmer test 2 results were lower in Sjögren's syndrome-type dry eye and were associated with positive staining of acinar cells with APO2·7 and of infiltrating lymphocytes with FasL. There was a good correlation between the results of Schirmer test 2 and APO2·7 and FasL staining. Lacrimal gland dysfunction is related to the apoptotic figure of acinar cells possibly induced by FasL on the infiltrating lymphocytes.