Grading of brain tumors by a lysosomal fragility test.

The stability of lysosomes is a function of osmotic pressure, temperature and time. Detailed studies have shown that the release and availability of lysosomal enzymes changes according to the degree of membrane permeability. This paper describes a modification of the controlled temperature and osmotic freezing-sectioning technique for characterization of lysosomal stability in brain tumors. The method is based on the enzyme measurements of released acid phosphatase from sections of unfixed tissue under appropriate physical conditions. The results suggest the possibility of a relation between lysosomal stages of activation, enzyme latency and brain tumor malignancy.