Intracisternal vs intraventricular injection of AAV1 result in comparable, widespread transduction of the dog brain.

Widespread distribution of transduced brain cells following delivery of AAV vectors into the cerebrospinal fluid (CSF) of the cisterna magna (CM) has been demonstrated in large animal brains. In humans, intraventricular injection is preferred to intracisternal injection for CSF delivery due to the risk of brain stem injury. One study in the dog reported adverse reactions to AAV vectors expressing GFP injected into the lateral ventricle but not when injected into the CM.

Performance of binary MLC using real-time optical sensor feedback system.

The Radixact system (Accuray Inc., Sunnyvale, CA) is the latest platform release based on the TomoTherapy technology. The most recent system does not apply a leaf latency model correction after plan optimization to ensure the correct MLC leaf-open time (LOT) agreement between the TPS and machine delivery.

Accumulation of alkyl-lysophosphatidylcholines in Niemann-Pick disease type C1.

Lysosomal function is impaired in Niemann-Pick disease type C1 (NPC1), a rare and inherited neurodegenerative disorder, resulting in late endosomal/lysosomal accumulation of unesterified cholesterol. The precise pathogenic mechanism of NPC1 remains incompletely understood. In this study, we employed metabolomics to uncover secondary accumulated substances in NPC1.

Widespread correction of brain pathology in feline alpha-mannosidosis by dose escalation of intracisternal AAV vector injection.

Alpha-mannosidosis is caused by a genetic deficiency of lysosomal alpha-mannosidase, leading to the widespread presence of storage lesions in the brain and other tissues. Enzyme replacement therapy is available but is not approved for treating the CNS, since the enzyme does not penetrate the blood-brain barrier. However, intellectual disability is a major manifestation of the disease; thus, a complimentary treatment is needed.

Beta-mannosidosis in a domestic cat associated with a missense variant in MANBA.

A 6-month-old cat of unknown ancestry presented for a neurologic evaluation due to progressive motor impairment. Complete physical and neurologic examinations suggested the disorder was likely to be hereditary, although the signs were not consistent with any previously described inherited disorders in cats. Due to the progression of disease signs including severely impaired motor function and cognitive decline, the cat was euthanized at approximately 10.

A Homozygous Missense Mutation in a Doberman Pinscher Dog with Neurodegeneration, Cytoplasmic Vacuoles, Autofluorescent Storage Granules, and an α-Mannosidase Deficiency.

A 7-month-old Doberman Pinscher dog presented with progressive neurological signs and brain atrophy suggestive of a hereditary neurodegenerative disorder. The dog was euthanized due to the progression of disease signs. Microscopic examination of tissues collected at the time of euthanasia revealed massive accumulations of vacuolar inclusions in cells throughout the central nervous system, suggestive of a lysosomal storage disorder.

Biodistribution of Adeno-Associated Virus Gene Therapy Following Cerebrospinal Fluid-Directed Administration.

Adeno-associated virus (AAV)-based gene therapies, exemplified by the approved therapy for spinal muscular atrophy, have the potential to deliver disease-course-altering treatments for central nervous system (CNS) indications. However, several clinical trials have reported severe adverse events, including patient deaths following high-dose systemic administration for muscle-directed gene transfer, highlighting the need to explore approaches utilizing lower doses when targeting the CNS. Animal models of disease provide insight into the response to new AAV therapies.

Efficacy and Safety of a Krabbe Disease Gene Therapy.

Krabbe disease is a lysosomal storage disease caused by mutations in the gene that encodes galactosylceramidase, in which galactosylsphingosine (psychosine) accumulation drives demyelination in the central and peripheral nervous systems, ultimately progressing to death in early childhood. Gene therapy, alone or in combination with transplant, has been developed for almost two decades in mouse models, with increasing therapeutic benefit paralleling the improvement of next-generation adeno-associated virus (AAV) vectors. This effort has recently shown remarkable efficacy in the canine model of the disease by two different groups that used either systemic or cerebrospinal fluid (CSF) administration of AAVrh10 or AAV9.

Meningeal B Cell Clusters Correlate with Submeningeal Pathology in a Natural Model of Multiple Sclerosis.

Multiple sclerosis (MS) is an idiopathic demyelinating disease in which meningeal inflammation correlates with accelerated disease progression. The study of meningeal inflammation in MS has been limited because of constrained access to MS brain/spinal cord specimens and the lack of experimental models recapitulating progressive MS. Unlike induced models, a spontaneously occurring model would offer a unique opportunity to understand MS immunopathogenesis and provide a compelling framework for translational research.

Low incidence of hepatocellular carcinoma in mice and cats treated with systemic adeno-associated viral vectors.

Adeno-associated viral (AAV) vectors have emerged as the preferred platform for gene transfer because of their combined efficacy and safety. However, insertional mutagenesis with the subsequent development of hepatocellular carcinomas (HCCs) has been recurrently noted in newborn mice treated with high doses of AAV, and more recently, the association of wild-type AAV integrations in a subset of human HCCs has been documented. Here, we address, in a comprehensive, prospective study, the long-term risk of tumorigenicity in young adult mice following delivery of single-stranded AAVs targeting liver.

Krabbe disease successfully treated via monotherapy of intrathecal gene therapy.

Globoid cell leukodystrophy (GLD; Krabbe disease) is a progressive, incurable neurodegenerative disease caused by deficient activity of the hydrolytic enzyme galactosylceramidase (GALC). The ensuing cytotoxic accumulation of psychosine results in diffuse central and peripheral nervous system (CNS, PNS) demyelination. Presymptomatic hematopoietic stem cell transplantation (HSCT) is the only treatment for infantile-onset GLD; however, clinical outcomes of HSCT recipients often remain poor, and procedure-related morbidity is high.

Global CNS correction in a large brain model of human alpha-mannosidosis by intravascular gene therapy.

Intravascular injection of certain adeno-associated virus vector serotypes can cross the blood-brain barrier to deliver a gene into the CNS. However, gene distribution has been much more limited within the brains of large animals compared to rodents, rendering this approach suboptimal for treatment of the global brain lesions present in most human neurogenetic diseases. The most commonly used serotype in animal and human studies is 9, which also has the property of being transported via axonal pathways to distal neurons.

Application of N-palmitoyl-O-phosphocholineserine for diagnosis and assessment of response to treatment in Niemann-Pick type C disease.

Niemann-Pick type C (NPC) disease is a rare lysosomal storage disorder caused by mutations in either the NPC1 or the NPC2 gene. A new class of lipids, N-acyl-O-phosphocholineserines were recently identified as NPC biomarkers. The most abundant species in this class of lipid, N-palmitoyl-O-phosphocholineserine (PPCS), was evaluated for diagnosis of NPC disease and treatment efficacy assessment with 2-hydroxypropyl-β-cyclodextrin (HPβCD) in NPC.

Cerebrospinal fluid and serum glycosphingolipid biomarkers in canine globoid cell leukodystrophy (Krabbe Disease).

Globoid cell leukodystrophy (GLD, Krabbe disease, Krabbe's disease) is caused by genetic mutations in the gene encoding, galactosylceramidase (GALC). Deficiency of this enzyme results in central and peripheral nervous system pathology, and is characterized by loss of myelin and an infiltration of globoid cells. The canine model of GLD provides a translational model which faithfully recapitulates much of the human disease pathology.

Pharmacokinetics and distribution of 2-hydroxypropyl-β-cyclodextrin following a single intrathecal dose to cats.

2-Hydroxypropyl-β-cyclodextrin (HP-β-CD) is an experimental therapy for Niemann-Pick disease type C (NPC) that reduced neuronal cholesterol and ganglioside storage, reduced Purkinje cell death, and increased lifespan in npc1-/- mice and NPC1 cats. In this study, tissue distribution was investigated in normal cats that received a single 120-mg dose of [ C]-HP-β-CD (approximately 200 μCi/cat) via the cerebellomedullary cistern (CBMC) and lumbar cistern. One cat was euthanized at each of various time points up to 24 hours postdose for subsequent processing and quantitative whole-body autoradiographic analysis.

Large animal models contribute to the development of therapies for central and peripheral nervous system dysfunction in patients with lysosomal storage diseases.

Lysosomal storage diseases (LSDs) are a group of 70 monogenic disorders characterized by the lysosomal accumulation of a substrate. As a group, LSDs affect ~1 in 5000 live births; however, each individual storage disease is rare, limiting the ability to perform natural history studies or to perform clinical trials. Perhaps in no other biomedical field have naturally occurring large animal (canine, feline, ovine, caprine, and bovine) models been so essential for understanding the fundamentals of disease pathogenesis and for developing safe and effective therapies.

-acyl--phosphocholineserines: structures of a novel class of lipids that are biomarkers for Niemann-Pick C1 disease.

Niemann-Pick disease type C1 (NPC1) is a fatal, neurodegenerative, cholesterol storage disorder. With new therapeutics in clinical trials, there is an urgency to improve diagnostics and monitor therapeutic efficacy with biomarkers. In this study, we sought to define the structure of an unknown lipid biomarker for NPC1 with [M + H] ion at 509.

A cross-species approach to disorders affecting brain and behaviour.

Structural and functional elements of biological systems are highly conserved across vertebrates. Many neurological and psychiatric conditions affect both humans and animals. A cross-species approach to the study of brain and behaviour can advance our understanding of human disorders via the identification of unrecognized natural models of spontaneous disorders, thus revealing novel factors that increase vulnerability or resilience, and via the assessment of potential therapies.

Accuracy of TomoEDGE dynamic jaw field widths.

Dynamic jaw delivery on the TomoTherapy H-series platform, entitled TomoEDGE™, is an effective tool to decrease the patient dose along the superior and inferior edges of the treatment target. The aperture of the TomoTherapy jaws, that is, field width (FW), defines the longitudinal dose profile. A consistent FW dose profile is an important quantity for accurate and reproducible dose delivery in TomoTherapy.

Quantitative DTI metrics in a canine model of Krabbe disease: comparisons versus age-matched controls across multiple ages.

Purpose The purpose of this study was to compare quantitative diffusion tensor imaging metrics in dogs affected with a model of Krabbe disease to age-matched normal controls. We hypothesized that fractional anisotropy would be decreased and radial diffusivity would be increased in the Krabbe dogs. Methods We used a highly reproducible region-of-interest interrogation technique to measure fractional anisotropy and radial diffusivity in three different white matter regions within the internal capsule and centrum semiovale in four Krabbe affected brains and three age-matched normal control brains.

LC3 Immunostaining in the Inferior Olivary Nuclei of Cats With Niemann-Pick Disease Type C1 Is Associated With Patterned Purkinje Cell Loss.

The feline model of Niemann-Pick disease, type C1 (NPC1) recapitulates the clinical, neuropathological, and biochemical abnormalities present in children with NPC1. The hallmarks of disease are the lysosomal storage of unesterified cholesterol and multiple sphingolipids in neurons, and the spatial and temporal distribution of Purkinje cell death. In feline NPC1 brain, microtubule-associated protein 1 light chain 3 (LC3) accumulations, indicating autophagosomes, were found within axons and presynaptic terminals.

AAVrh10 Gene Therapy Ameliorates Central and Peripheral Nervous System Disease in Canine Globoid Cell Leukodystrophy (Krabbe Disease).

Globoid cell leukodystrophy (GLD), or Krabbe disease, is an inherited, neurologic disorder that results from deficiency of a lysosomal enzyme, galactosylceramidase. Most commonly, deficits of galactosylceramidase result in widespread central and peripheral nervous system demyelination and death in affected infants typically by 2 years of age. Hematopoietic stem-cell transplantation is the current standard of care in children diagnosed prior to symptom onset.

Canine and Feline Models of Human Genetic Diseases and Their Contributions to Advancing Clinical Therapies .

For many lethal or debilitating genetic disorders in patients there are no satisfactory therapies. Several barriers exist that hinder the developments of effective therapies including the limited availability of clinically relevant animal models that faithfully recapitulate human genetic disease. In 1974, the Referral Center for Animal Models of Human Genetic Disease (RCAM) was established by Dr.

Evaluation of Intrathecal Routes of Administration for Adeno-Associated Viral Vectors in Large Animals.

Delivery of adeno-associated viral (AAV) vectors into the cerebrospinal fluid (CSF) can achieve gene transfer to cells throughout the brain and spinal cord, potentially making many neurological diseases tractable gene therapy targets. Identifying the optimal route of CSF access for intrathecal AAV delivery will be a critical step in translating this approach to clinical practice. We previously demonstrated that vector injection into the cisterna magna is a safe and effective method for intrathecal AAV delivery in nonhuman primates; however, this procedure is not commonly used in clinical practice.