The Relationship of Serum Lysozyme to Leukocytes and other Constitutional Factors

The primary objective of this study was to explore the relationship between leukocyte turnover and serum lysozyme. Polymorphonuclear leukocytes and monocytes contain relatively high concentrations of this enzyme,1"2 and it seems possible that the major portion of the lysozyme found in plasma is derived from the eventual breakdown of these cells. Thus, variations in rates of leukocyte production and destruction would alter serum lysozyme concentration. In order to evaluate these relationships, however, it was necessary to determine the influence of age, sex and certain other constitutional factors on serum lysozyme. Of special interest in this study was whether or not serum lysozyme levels might reflect alterations in leukocyte or other body tissue turnover in subjects previously exposed to excessive amounts of ionizing radiation. Previous investigations with the enzyme, lysozyme, suggest its suitability for studies of this type. Lymphocytes and erythrocytes contain little or none1'2 while certain other body cells contain moderate to relatively large concentrations."1 Following in vitro physical disruption of leukocytes some of the enzyme is released,"' but much of it probably remains firmly within granules and other cellular components. Additional experimental evidence has shown that in vivo lysis of granulocytes will elevate serum lysozyme.12