Immunohistological demonstration of lysozyme in human leucocytes, salivary corpuscles and nasal discharge cells after blockade of myeloperoxidase activity.

Using a peroxidase-antiperoxidase method, the intracellular lysozyme (LZM) content of human blood cells, salivary corpuscles and nasal discharge cells was estimated after blockade of myeloperoxidase activity. The endogenous myeloperoxidase activity was entirely blocked by 0.3% hydrogen peroxide-methanol treatment in the polymorphonuclear leucocytes. In the peripheral blood of healthy subjects and various leukaemic patients, mature neutrophilic polymorphonuclear leucocytes and immature ones from promyelocytes onwards were distinctly observed with the immuno-specific reaction. Occasionally, monocytes were also found to contain LZM intracellularly. There was no discernible enzyme in the other blood cell elements. In salivary corpuscles and nasal discharge cells, neutrophilic granulocytes only demonstrated LZM immunopositively.