[Radioimmunological assay of human lysozyme and effect of exertion on its blood level].

Radioimmunoassay (RIA) of human lysozyme was developed using 125I-lysozyme and specific antiserum to the enzyme. Titre of antibodies produced in the antiserum was as high as 1:81,000, affinity constant constituted 1.3.10(9) M/L. Optimum patterns of the RIA were achieved under the following conditions: B0 = 50-55%, T = 25-30.10(3) cpm, BSA = 0.5%, NaCl = 0.85%, charcoal 2.5%. The antibody-antigen reaction was carried out within 30 min, 30 and 15 min at 37 degrees, 20 degrees and 4 degrees, respectively. The RIA enabled to estimate lysozyme with sensitivity of 0.25 ng/ml, while the standard curve was optimal within the range of 0.1-1.0 ng/tube. Intra- and inter-assay coefficients did not exceed 4% and 8%, respectively. Recovery of the standard lysozyme concentration was equal to 96.5 +/- +/- 0.8%. As shown by the RIA intensive physical exercises resulted in an increase of lysozyme content in blood, which appears to occur due to the enzyme secretion from phagocytes. Calculation of the secretion index may be used for evaluation of blood phagocytes functional state.