Multiple lysosomal enzyme deficiency in man

The purpose of the experiments described in this thesis was to gain more insight into the molecular and genetic nature of these diseases. Different approaches were used: Somatic cell hybridization and co-cultivation studies were performed, to clarify whether different gene mutations were responsible for the deficiency of a given enzyme in various related diseases. "Cybridization" studies were carried out after fusion of whole fibroblasts ·and enucleated cells (cytoplasts), to further investigate whether the presence of the nucleus of one of the cell types hybridized was mandatory for complementation or cytoplasmic factors were sufficient for this event to occur. Immunoprecipitation of radiolabelled lysosomal glycoproteins, followed by SDS gel electrophoresis, was applied as a method to verify the possible molecular and biochemical changes of a deficient enzyme (Sgalactosidase) in comparison with its normal counterpart

Mouse model for the lysosomal disorder galactosialidosis and correction of the phenotype with overexpressing erythroid precursor cells.

The lysosomal storage disorder galactosialidosis results from a primary deficiency of the protective protein/cathepsin A (PPCA), which in turn affects the activities of beta-galactosidase and neuraminidase. Mice homozygous for a null mutation at the PPCA locus present with signs of the disease shortly after birth and develop a phenotype closely resembling human patients with galactosialidosis. Most of their tissues show characteristic vacuolation of