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Single radial immunodiffusion method was used to measure the concentration of IgG, IgA, IgM and IgD in tears of 220 healthy individuals aged from 2 to 86 years. Relation of the values to age and sex has been evaluated statistically by regression analysis method. Mean IgA level was 30.7 mg/100 ml. IgG could be detected in 200 samples and the level was less than 1 mg/100 ml. IgM was detected in only 7 samples and the value was less than 1 mg/100 ml. IgD could not be detected in any of the sample. The IgA level in males and that in females differs significantly, the females having a higher mean value. The IgA level appears to increase in both sexes with age. No relationship with age and sex could be established in other types of immunoglobulins.
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Sen et al. (1978) studied this question.
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