title: Chaperone-mediated gene therapy with recombinant AAV-PPCA in a new mouse model of type I sialidosis.
abstract: The lysosomal storage disease sialidosis is caused by a primary deficiency of the sialidase N-acetyl-α-neuraminidase-1 (NEU1). Patients with type I sialidosis develop an attenuated, non-neuropathic form of the disease also named cherry red spot myoclonus syndrome, with symptoms arising during juvenile/ adult age. NEU1 requires binding to its chaperone, protective protein/cathepsin A (PPCA), for lysosomal compartmentalization, stability and catalytic activation. We have generated a new mouse model of type I sialidosis that ubiquitously expresses a NEU1 variant carrying a V54M amino acid substitution identified in an adult patient with type I sialidosis. Mutant mice developed signs of lysosomal disease after 1year of age, predominantly in the kidney, albeit low residual NEU1 activity was detected in most organs and cell types. We demonstrate that the activity of the mutant enzyme could be effectively increased in all systemic tissues by chaperone-mediated gene therapy with a liver-tropic recombinant AAV2/8 vector expressing PPCA. This resulted in clear amelioration of the disease phenotype. These results suggest that at least some of the NEU1 mutations associated with type I sialidosis may respond to PPCA-chaperone-mediated gene therapy.
authors.affiliation: Department of Genetics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Bonten
authors.forename: Gouri
authors.initials: G
authors.lastname: Yogalingam
authors.forename: Huimin
authors.initials: H
authors.lastname: Hu
authors.forename: Elida
authors.initials: E
authors.lastname: Gomero
authors.forename: Diantha
authors.initials: D
authors.lastname: van de Vlekkert
authors.forename: Alessandra
authors.initials: A
authors.lastname: d'Azzo
mesh_terms: D000818:Animals; D000229:Dependovirus / Q000235:genetics*; D004195:Disease Models, Animal; D015316:Genetic Therapy; D051379:Mice; D018345:Mice, Knockout; D018832:Molecular Chaperones / Q000378:metabolism*; D009081:Mucolipidoses / Q000628:therapy*; D011995:Recombination, Genetic
chemical_list: D018832:Molecular Chaperones
keywords: AAV; BMEF; Chaperone-mediated therapy; ERT; FACE; GS; Gene therapy; IHC; KO; KO/TG; LSD; Lysosomal storage disease; NEU1; PCT; PPCA; Sialidosis; WT; bone marrow extracellular fluid; enzyme replacement therapy; fluorophore-assisted carbohydrate electrophoresis; galactosialidosis; immunohistochemistry; knockout; knockout–transgenic; lysosomal storage disease; pharmacologic-chaperone therapy; protective protein/cathepsin A; scAAV; self-complementary adeno-associated virus; wild-type