[Clinical evaluation of a measurement method for secretory IgA in tears]
Mai Hoshino1, Jun Shoji, Noriko Inada
1Department of Ophthalmology, Nihon University School of Medicine, Tokyo 173 8610, Japan.
Purpose:
To evaluate the efficacy of measurement of secretory IgA (sIgA) in tears with tear sampling methods using filter paper, and to review sIgA measurement method for clinical application.
Subjects And Methods:
Subjects were divided into the following 4 groups: a healthy control group, 29 eyes of 29 subjects; a contact lens group, 15 eyes of 15 subjects; a dry eye group, 13 eyes of 13 subjects; and a herpes group, 6 eyes of 6 subjects. In all subjects the sIgA value in tears was measured. In addition, in eighteen eyes of 18 healthy control individuals, the tear sIgA value was measured three times, morning, noon, and night in one day, and the variation of tear sIgA value was checked. The tears were sampled by the Schirmer 1 method. Schirmer papers were eluted in 200 microl of 0.5 M NaCl and 0.5% Tween 20 in 0.05 M phosphate-buffered solution (pH 7.2). Tear sIgA value was measured by ELISA (enzyme-linked immunosorbent assay).
Results:
Tear sIgA value was 1249.0+/-1025.0 microg/ ml in the healthy control group; 1057.4+/-1583.3 microg /ml in the contact len groups; 197.8+/-91.3 microg/ml in the dry eye group; and 759.7+/-467.8 microg/ml in the herpes group. There was no significant difference between the healthy control group and the contact lens group, or the control group and the herpes group. There was a significantly (p<0.0001) low value in the dry eye group in comparison with the healthy control group. In the 18 healthy control individuals, there was a tendency for the tear sIgA value collected at noon to be higher.
Conclusion:
Measurment of the changes in tear sIgA values caused by inflammation of the lacrimal gland is useful as a clinical test of lacrimal gland function.
