Group II PLA2 Content of Tears in Normal Subjects

PURPOSE. To determine the concentration of group II phospholipase (PL) A 2 , an antimicrobial molecule, in tears of normal subjects in different age and sex groups. METHODS. PLA 2 content of tears was measured in 122 healthy volunteers with ages ranging from 20 to 89 years (mean, 49.5 years) by a time-resolved fluoroimmunoassay using a polyclonal rabbit antibody to recombinant human PLA 2 . RESULTS. The mean concentration of PLA 2 in tears was 54.5 ± 33.9 μg/ml. It was highest in the age group 20 to 29 years (81.6 ± 32.0 μg/ml), and a decrease of concentration occurred with an increase of age. PLA 2 values were statistically significantly lower in the age group 60 to 69 years (P = 0.0013) and 70 years or more (P = 0.0001) than in the age group 20 to 29 years. There were no statistically significant differences in PLA 2 content of tears between the genders in any age group (P = 0.798). CONCLUSIONS. The results indicate that tears contain a high concentration of PLA 2 and that PLA 2 levels decrease with an increase of age and/or reflex tear component of the sample analyzed.