Ceruloplasmin in Wilson's disease.

Ceruloplasmin was highly purified from one patient with Wilson's disease and partially purified from a second unrelated patient. The highly purified ceruloplasmin was indistinguishable from normal ceruloplasmin by electrophoresis, tryptic peptide map, oxidase activity, and copper, amino acid, and sugar composition. The partially purified ceruloplasmin was indistinguishable electrophoretically from normal ceruloplasmin. With penicillamine therapy, ceruloplasmin disappeared from the serum of the first patient; it reappeared after the drug was discontinued. The significance of this observation in regard to the basic defect in Wilson's disease is discussed.