title: Intracerebroventricular infusion of acid sphingomyelinase corrects CNS manifestations in a mouse model of Niemann-Pick A disease.
abstract: Niemann-Pick A (NPA) disease is a lysosomal storage disorder (LSD) caused by a deficiency in acid sphingomyelinase (ASM) activity. Previously, we showed that the storage pathology in the ASM knockout (ASMKO) mouse brain could be corrected by intracerebral injections of cell, gene and protein based therapies. However, except for instances where distal areas were targeted with viral vectors, correction of lysosomal storage pathology was typically limited to a region within a few millimeters from the injection site. As NPA is a global neurometabolic disease, the development of delivery strategies that maximize the distribution of the enzyme throughout the CNS is likely necessary to arrest or delay progression of the disease. To address this challenge, we evaluated the effectiveness of intracerebroventricular (ICV) delivery of recombinant human ASM into ASMKO mice. Our findings showed that ICV delivery of the enzyme led to widespread distribution of the hydrolase throughout the CNS. Moreover, a significant reduction in lysosomal accumulation of sphingomyelin was observed throughout the brain and also within the spinal cord and viscera. Importantly, we demonstrated that repeated ICV infusions of ASM were effective at improving the disease phenotype in the ASMKO mouse as indicated by a partial alleviation of the motor abnormalities. These findings support the continued exploration of ICV delivery of recombinant lysosomal enzymes as a therapeutic modality for LSDs such as NPA that manifests substrate accumulation within the CNS.
authors.affiliation: Genzyme Corporation, 49 New York Avenue, Framingham, MA 01701, USA. jim.dodge@genzyme.com
authors.forename: James C
authors.initials: JC
authors.lastname: Dodge
authors.forename: Jennifer
authors.initials: J
authors.lastname: Clarke
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Treleaven
authors.forename: Tatyana V
authors.initials: TV
authors.lastname: Taksir
authors.forename: Denise A
authors.initials: DA
authors.lastname: Griffiths
authors.forename: Wendy
authors.initials: W
authors.lastname: Yang
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Fidler
authors.forename: Marco A
authors.initials: MA
authors.lastname: Passini
authors.forename: Kenneth P
authors.initials: KP
authors.lastname: Karey
authors.forename: Edward H
authors.initials: EH
authors.lastname: Schuchman
authors.forename: Seng H
authors.initials: SH
authors.lastname: Cheng
authors.forename: Lamya S
authors.initials: LS
authors.lastname: Shihabuddin
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D004195:Disease Models, Animal; D006801:Humans; D007276:Injections, Intraventricular / Q000379:methods; D008247:Lysosomes / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D052536:Niemann-Pick Disease, Type A / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D013108:Sphingomyelin Phosphodiesterase / Q000008:administration & dosage* / Q000172:deficiency / Q000378:metabolism; D013109:Sphingomyelins / Q000378:metabolism; D013997:Time Factors
chemical_list: D013109:Sphingomyelins; D002784:Cholesterol; D013108:Sphingomyelin Phosphodiesterase