340 likes | 355 Views
Multimodal Therapies for Lysosomal Storage Diseases. Mark S. Sands, Ph.D. Washington University School of Medicine Departments of Medicine and Genetics. Financial Disclosures:. Research Support/Grants: BioMarin Pharmaceuticals - M. Sands, PI
E N D
Multimodal Therapies for Lysosomal Storage Diseases Mark S. Sands, Ph.D. Washington University School of Medicine Departments of Medicine and Genetics
Financial Disclosures: Research Support/Grants:BioMarin Pharmaceuticals - M. Sands, PI Consulting:Consultant - BioMarin PharmaceuticalsConsultant - LA BioMedConsultant - University of Minnesota
Lysosomal Storage Diseases - Rare pediatric disorders ≥ 50 distinct diseases - Collectively: ≈1 in 5,000 live births - Inherited deficiency in a lysosomal enzyme - Intralysosomal accumulation of undegraded material - Affects many cell types - Common clinical signs: CNS involvement* Organomegally Skeletal defects Cardiac defects Auditory deficits Retinal degeneration
Globoid-Cell Leukodystrophy (Krabbe Disease) - Autosomal recessive, neurodegenerative disease - Galactocerebrosidase deficiency (lysosomal enzyme) - Removes galactose from galactosylated lipids • galactosylceramide • galactosylsphingosine (psychosine, cytotoxic) - Demyelinating/Dysmyelinating disease - Progressive neuroinflammation - CNS and PNS involvement - Seizures - Death – 2-4 years of age
Murine Model of Krabbe Disease (Twitcher Mouse) • Galactocerebrosidase-deficient • De/Dysmyelinating disease • CNS and PNS involvement • Rapid progression (life span ~40d) • Severe tremor • Hind limb ataxia • Progressive neuroinflammation
Treatment of Krabbe Disease 1) 1st BMT performed in 1984 (Yeager et al., Science, 1984) -Life span ~80 d 2) Similar response in children (standard-of-care) 3) Refractory to nearly every treatment attempted • Stem cell transplantation • Anti-inflammatories • Anti-oxidents • Substrate reduction • Dietary intervention • CNS-directed gene therapy • etc.
Krabbe Disease 1) Simple monogenic disease 2) Complicated disease presentation • Enzyme deficiency • Cytotoxic metabolite accumulation • Oligodendrocyte death • Neuroinflammation • Oxidative stress • CNS & PNS involvement • etc.
Combination Therapy: Targeting Different Pathogenic Mechanisms CNS-Directed AAV-Mediated Gene Therapy + Bone Marrow Transplantation
Double Combination(Rationale) Primary Genetic Defect Gene Therapy Accumulation of substrates ? ? Bone Marrow Transplant Inflammation Death and Destruction
Experimental Design(AAV2/5 + BMT) 400rads radiation IV injection of GFP+ BM cells Genotype PND2 PND4 PND3 IC and IT injection of GALC-AAV2/5
GALC Activity Reddy AS, et al., (2011) J. Neurosci31:9945
Psychosine Reddy et al., (2011) J. Neurosci31:9945
Life Span (≈130 d) (≈70 d) Reddy et al., (2011) J. Neurosci31:9945
BMT-Immunomodulation Reddy et al., (2011) J. Neurosci31:9945
Combination Therapy: Targeting Different Pathogenic Mechanisms CNS-Directed AAV2/5-Mediated Gene Therapy + Bone Marrow Transplantation + Substrate Reduction Therapy
Triple Combination(Rationale) Primary Genetic Defect Gene Therapy Substrate Reduction Therapy Accumulation of substrates L-cycloserine Bone Marrow Transplant Inflammation Death and Destruction
AAV2/5 + BMT + L-cycloserine experimental design 400rads radiation i.v. injection of GFP+ BM cells Genotype PND2 PND4 PND3 3X weekly SubQ injections of L-cycloserine (50mg/kg) i.c. and i.t. injection of GALC-AAV2/5
Increased GALC Activity Hawkins-Salsbury J, et al., (2015) J Neurosci 35:6495
Reduced Psychosine - Brain Hawkins-Salsbury J, et al., (2015) J Neurosci 35:6495
Substrate Reduction (L-cycloserine) Hawkins-Salsbury J, et al., (2015) J Neurosci 35:6495
Increased Myelin & Decreased Infiltrates Hawkins-Salsbury J, et al., (2015) J Neurosci 35:6495
Life Span ~175d↑ Hawkins-Salsbury J, et al., (2015) J Neurosci 35:6495
36d Twi-/- vs. 454d Triple-Treated Twi-/- Li et al., in preparation
Combination Therapy: Targeting Different Compartments Infantile Neuronal Ceroid Lipofuscinosis (Infantile Batten Disease)
Infantile Batten Disease (INCL) - Palmitoyl protein thioesterase 1 (PPT1)-deficient - Accumulation of autofluorescent material - Neurodegeneration - Severe brain atrophy - Neuroinflammation - Retinal degeneration/visual deficits - Intractable Seizures
Infantile Batten Disease (INCL) Vesa et al, (1995) Nature 376:584
cortex HPC 0.25 mV 5 s I II III IV I II V III IV V VI VI NORMAL PPT1-/- Murine Model of INCL PPT1-deficient Autofluorescent accumulation Neurodegeneration Severe brain atrophy Spontaneous seizures Median life span ~8.5mo Neuroinflammation Gupta et al, (2001) Proc NatlAcadSci 98:13566
Brain-Directed Gene Therapy for Murine INCL • Intracranial injections of AAV-PPT1 @ birth • ≥ Normal levels of PPT1 • Modest response • Median life span ≈ 10-12 mo (untreated ≈ 8.5 mo) Griffey et al., (2005) MolTher13:538 Macauley et al., (2014) J Neurosci34:13077
Spinal Cord Disease In INCL *Spinal cord disease is severe and precedes the brain disease Shyng et al., (2017) ProcNatlAcadSci114:E5920
Reciprocal Enzyme Distribution (Intracranial vs. Intrathecal) Shyng et al., (2017) ProcNatlAcadSci114:E5920
Intracranial + Intrathecal AAV-Mediated Gene Therapy Shyng et al., (2017) ProcNatlAcadSci114:E5920
Intracranial + Intrathecal AAV-Mediated Gene Therapy Shyng et al., (2017) ProcNatlAcadSci114:E5920
Conclusions: • Targeting multiple pathogenic mechanisms dramatically increases therapeutic efficacy (Krabbe) a) AAV-mediated gene therapy provides a persistent source of GALC to the CNS b) BMT synergizes with AAV and decreases disease- and AAV-associated inflammation c) Additional synergy observed when SRT is combined with AAV and BMT • Targeting different CNS compartments dramatically increases therapeutic efficacy (INCL) a) Brain- and spinal cord-directed gene therapy dramatically increase efficacy
Sands Lab: Darshong Lin Adarsh Reddy Jacqui Hawkins-Salsbury Yedda Li Lauren Shea Megan Griffey Shannon Macauley Charles Shyng Marie Roberts Support NIH – R01NS43205 & R01HD55461 NRSA Fellowship F31 NS056718 BDSRA Postdoctoral Fellowship Hunter’s Hope Foundation NTSAD Foundation Legacy of Angels Foundation Acknowledgements Washington University: • David Wozniak (Mouse Behavioral Core) • Mike Wong (Electroencephalography) • Daniel Ory (Mass Spec Core) King’s College - London • Catherine Kielar • Hemanth Nelvagal • Jonathan Cooper