Distribution of lysozyme in the serum, urine and kidneys of akr mice during the pathogenesis of lynphocytic leukemia.

Abstract

The distribution of lysozyme in the serum, urine and kidney homogenates was studied in normal young (less than 4 months) AKR mice, in old (more than 8 months) AKR mice that bore a spontaneous lymphocytic leukemia and in young AKR mice in whom this leukemia had been transplanted. Much higher concentrations of lysozyme were detected in the kidney homogenates of the old mice than among the young mice. However, after the injection of leukemic cells into the young mice, increased concentrations of lysozyme were detected in their kidneys as well. Concentrations of lysozyme in the serum did not vary markedly in either age group or during the course of leukemic cell proliferation. During the pathogenesis of the transplanted leukemia, morphological changes were observed within the proximal tubular cells of the kidneys by light microscopy, and by the cytochemical demonstration of lysozyme using an immunoperoxidase technique. The number and size of dense and lysozyme‐positive granules of the proximal tubular cells increased concomitantly with the increase in lysozyme levels in kidney homogenates. Lysozymuria developed in the advanced stages of the disease and was associated with morphological signs of tubular cell damage. The findings of elevated lysozyme levels in leukemic mice are discussed as a phenomenon related to the stimulation of the reticuloendothelial system induced either by the injected leukemic cells or by the viral agent associated with this lymphocytic leukemia.