Isolation of human urinary lysozyme.

For the isolation of human lysozyme from the urine of leukemia patients, a simple method has been established which involves precipitation of urinary proteins by 60% saturation with ammonium sulfate, fractionation of crude lysozyme on Sephadex G-50 and purification by CM-Sepharose chromatography. By this method approximately 60% of the lysozyme in the urine was isolated in a pure state in ten days.