Application of magnetic chromatography to the isolation of lysosomes from fibroblasts of patients with lysosomal storage disorders

A method for the purification of lysosomes from fibroblasts has been develo ped which uses endocytosis of superparamagnetic colloidal iron dextran part icles followed by separation of the iron-containing lysosomes in a magnetic field. This permitted isolation of lysosomes from fibroblasts from patient s with infantile sialic acid storage disorder and other lysosomal storage d iseases in which a shift in lysosomal density induced by the storage materi al prevents purification by centrifugation in a Percoll gradient, The magne tic lysosomes isolated from these cells are very similar to those from norm al cells as judged by lysosomal marker enzyme activity and 2D-PAGE analysis of the enriched proteins. (C) 1998 Federation of European Biochemical Soci eties.