title: Radioimmunoassay for urinary lysozyme in human serum from leukemic patients.
abstract: We present a radioimmunoassay for lysozyme in human serum, based upon human lysozyme isolated from the urine of leukemic patients and antiserum prepared against this lysozyme in the goat. 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.
mesh_terms: D006801:Humans; D007938:Leukemia / Q000201:enzymology*; D009113:Muramidase / Q000097:blood* / Q000302:isolation & purification / Q000652:urine; D011863:Radioimmunoassay / Q000379:methods
chemical_list: D009113:Muramidase