New targets for old diseases: lessons from mucolipidosis type II

Lysosomal storage disorders (LSDs) are inherited diseases characterized by progressive intracellular accumulation of undigested macromolecules within the cell due to specific lysosomal defects. Lysosomal storage results in a global impairment ofmany lysosome‐dependent pathways (e.g. autophagy and endocytosis), leading to cellular dysfunction and death (Ballabio &Gieselmann, 2009). LSD patients often have a complex phenotype, with visceral, skeletal, haematological and neurological involvement. Several mechanisms underlie the etiopathogenesis of the LSDs and their relative contribution may vary, depending on the tissue and cell type. For instance, a generalized inflammatory process affecting multiple tissues has been observed in several mouse models of LSDs, although its role in disease pathogenesis remains still largely unclear (Ballabio & Gieselmann, 2009).