Radioimmunoassay for urinary lysozyme in human serum from leukemic patients
In the separation step, a second antibody is used. By properly adjusting the concentrations of unlabeled and 125I-labeled lysozyme and of the antibodies, maximal precision (SD, 0.04 mg/litre) was obtained in the range 0.00 to 2.00 mg/litre.
In 20 normal volunteers the lysozyme concentration was 4.6 +/- 0.8
mg/litre (mean +/- SD), in 13 patients with monocytic leukemia 34.4
+/- 8.6 mg/litre. Correlation with lysoplate determinations was excellent
in leukemic sera (r = 0.97) but was poor in normal sera (r = 0.35),
possibly owing to the existence of isoenzymes