Gene Therapy in a Mouse Model of Niemann–Pick Disease Type C1

Abstract

Niemann-Pick disease type C1 (NPC1) is a fatal congenital neurodegenerative disorder caused by mutations in the NPC1 gene, which is involved in cholesterol transport in lysosomes. Broad clinical manifestations of NPC1 include liver failure, pulmonary disorder, neurological deficits, and psychiatric symptoms. The main cause of death in NPC1 patients involves central nervous system (CNS) dysfunction; there is no essential treatment. We generated a tyrosine-mutant adeno-associated virus (AAV) 9/3 vector that expresses human NPC1 under a cytomegalovirus (CMV) promoter (AAV-CMV-hNPC1) and injected it into the left lateral ventricle (5 lL) and cisterna magna (10 lL) of Npc1 homo-knockout (Npc1 -/-) mice. Each mouse received total 1.35 • 10 11 vector genome on days 4 or 5 of life. AAV-treated Npc1 -/mice (n = 11) had an average survival of >28 weeks, while all saline-treated Npc1 -/mice (n = 11) and untreated Npc1 -/mice (n = 6) died within 16 weeks. Saline-treated and untreated Npc1 -/mice lost body weight from 7 weeks until death. However, the average body weight of AAV-treated Npc1 -/mice increased until 15 weeks. AAV-treated Npc1 -/mice also showed a significant improvement in the rotarod test performance. A pathological analysis at 11 weeks showed that cerebellar Purkinje cells were preserved in AAV-treated Npc1 -/mice. In contrast, untreated Npc1 -/mice showed an almost total loss of cerebellar Purkinje cells. Combined injection into both the lateral ventricle and cisterna magna achieved broader delivery of the vector to the CNS, leading to better outcomes than noted in previous reports, with injection into the lateral ventricles or veins alone. In AAV-treated Npc1 -/mice, vector genome DNA was detected widely in the CNS and liver. Human NPC1 RNA was detected in the brain, liver, lung, and heart. Accumulated unesterified cholesterol in the liver was reduced in the AAV-treated Npc1 -/mice. Our results suggest the feasibility of gene therapy for patients with NPC1.

MiR-25 blunts autophagy and promotes the survival of Mycobacterium tuberculosis by regulating NPC1

“…NPD-type C disease caused by NPC1 mutation is a neurodegenerative disease. The mouse model with NPC1 mutation will show mild cerebellar ataxia and other neurological symptoms from 6 weeks of age and continue to worsen ( Colombo et al., 2021 ; Meneses-Salas et al., 2021 ; Kurokawa et al., 2021 ). Therefore, we performed NPC1-related functional verification in vitro .…”

Therapeutic efficacy of rscAAVrh74.miniCMV.LIPA gene therapy in a mouse model of lysosomal acid lipase deficiency

“…This dose is in the range currently used in clinical and pre-clinical treatment of Niemann-Pick disease and various lysosomal storage disorders. 42 , 43 , 44 , 45 , 46 , 47 To further decrease the suggested dose, we could use serotypes that have increased tropism to the liver; AAV-DJ, for example, is an engineered strain created by capsid shuffling that has been shown to be highly specific to the liver. 48 …”

“…This dose is in the range currently used in clinical and pre-clinical treatment of Niemann-Pick disease and various lysosomal storage disorders. [42][43][44][45][46][47] To further decrease the suggested dose, we could use serotypes that have increased tropism to the liver; AAV-DJ, for example, is an engineered strain created by capsid shuffling that has been shown to be highly specific to the liver. 48 The current standard of treatment for LAL-D is weekly or bi-weekly infusions of enzyme replacement therapy (ERT) of sebelipase alfa (Kanuma), a recombinant form of the human LAL enzyme.…”

In vivo targeting of a variant causing vanishing white matter using CRISPR/Cas9

“…For the experimental group receiving CRISPR/Cas9 treatment, 1.05E 11 vg in 3 μL was injected per lateral ventricle. 35 , 36 , 37 , 38 For the control group, AAV-Cas9 virus was mixed with saline. A microinfusion pump controlled a 10-μL syringe (Hamilton) with 34G beveled needle (World Precision Instruments) in a stereotaxic instrument to slowly inject 9 in predetermined coordinates (millimeters from Lambda: X = ±0.8, Y = ±1.5, Z = −1.7, −1.5) as described.…”