The Glycoproteinoses: An International Workshop on Advances in Pathogenesis and Therapy

Meeting Summary

The Glycoproteinoses: An International Workshop on Advances in Pathogenesis and Therapy
National Institute of Neurological Disorders and Stroke
DoubleTree Hotel and Executive Meeting Center
Rockville, Maryland, USA
April 1-2, 2004

Overview

The National Institute of Neurological Disorders and Stroke (NINDS) and the Office of Rare Diseases (ORD) at NIH along with the International Society for Mannosidosis & Related Diseases, Inc. (ISMRD) co-sponsored this workshop. This scientific workshop was organized by Dr. Danilo A. Tagle (NINDS), Dr. Allesandra d'Azzo (St. Jude's Childrens Hospital), Dr. Leena Peltonen (UCLA) and Steven Walkley (Albert Einstein). The workshop addressed the following key questions and issues:

• What is the pathomechanism on how defects in processing glycoproteins (as opposed to glycoaminoglycans) in the endosomal-lysosomal system lead to disease?
• What are the commonalities and differences for each disease type?
• Can the success in ERT and CMT treatment, particularly for a -mannosidosis, be translated to other related disorders?
• How should assessments be conducted for any proposed treatment(s)?

The goals of this workshop include:

• To provide scientists and clinicians working or interested in these group of disorders an opportunity to gather and to discuss avenues for medical and research breakthroughs
• To facilitate data- and resource-sharing amongst investigators, including newly characterized animal models
• To foster collaborations amongst scientists and interactions with patients and families

The workshop attended by approximately 50 scientists from North America, Europe and the Pacific, all with interests and experience in the study of glycoprotein storage diseases (see list of participants). Also in attendance were a number of individuals from families affected by glycoprotein storage diseases. The meeting began with a series of lectures on how proteins are glycosylated (Dr. S. Kornfeld), how they are eventually degraded in lysosomes (Dr. B. Winchester), and what happens when defects occur in lysosomes which block this normal degradation (Dr. M.Patterson). In Session 2, mechanisms by which the inherited defects in lysosomes actually cause cell dysfunction and disease were explored. Dr. D. Marks, from the laboratory of Dr. R. Pagano, and Dr. S. Walkley spoke of the importance of secondary sequestration of cholesterol and glycosphingolipids and its potential consequences in lysosomal diseases. Dr. A. Cuervo discussed the degradation of cytosolic proteins in lysosomes and of the overall mechanism of chaperone-mediated autophagy. Drs. E. Neufeld and R. Proia discussed their studies on the importance of microglia and brain inflammation as participating in lysosomal disease pathogenesis, as well as possible significant differences between different types of disorders in terms of the microglial-mediated response. Dr. A. d'Azzo spoke of mechanisms contributing to neuron death in the lysosomal disease, GM1 gangliosidosis. Sessions 3 and 4 were focused on discussions of many available animal models of glycoprotein storage diseases as well as molecular mechanisms contributing to individual diseases. Included here were reports of glycoprotein storage diseases in mice, guinea pigs, cats, dogs, goats and cattle, and presentations by Drs. M. Haskins, A. Jalanko, J. Hopwood, D. Schindler, A. d'Azzo, P. Lobel, and W. Sly. There were also 2 sessions of speakers focused on therapeutic strategies in lysosomal diseases. Included here were reports on enzyme replacement therapy in alpha-mannosidosis by Dr. P. Saftig, mechanisms by which microglia may transfer enzyme to diseased neurons by Dr. K. Dobrenis, the use of cord blood and hematopoietic stem cell transplants by Drs. M. Escolar and C. Peters, respectively, and the use of adenoviral and lentiviral vectors for gene therapy by Drs. M. Sands and J. Medin, respectively. This session ended with a report on the use of an adenoviral vector for the treatment of brain disease in an animal model of alpha-mannosidosis by Dr. C. Vite.

Several new investigators to the field were also invited to attend the meeting and to present their findings on lysosomal diseases, including Dr. Y-P Wu (mechanisms of inflammation in storage diseases), Dr. C. Tifft (surrogate markers of lysosomal disease progression), Dr. K. Ohmi (the role of gliosis in storage disease), Dr. M. Ellinwood (a newly discovered model of mucopolysaccharidosis type IIIB), Dr. M. Yoshimitsu (the use of lentiviral vectors in gene therapy), Dr. G. Yogalingam (the use of PPCA as therapy for sialidosis) and Dr. D. Wang (enzyme replacement therapy in sialidosis and galactosialidosis).

Recommendations

The meeting closed with a roundtable discussion of pathogenic mechanisms, animal models, treatment strategies, future research priorities and research collaborations, and funding strategies, chaired by Dr. S. Kornfeld and addressed by Drs. M. Haskins, J. Hopwood, L. Neufeld, D Malm, and W. Sly. Consensus emerged on several points. Firstly, one of the major areas where our knowledge of glycoprotein storage diseases was believed most limited was in the actual mechanisms by which lysosomal dysfunction leads to cell and organ failure, particularly for brain as well as for bone and cartilage. Secondly, the availability of animal models of lysosomal diseases was viewed as a major research resource for both understanding issues of pathogenesis and for evaluating potential therapies. The one notable omission in terms of disease models was of a mouse model of fucosidosis, which many felt would be a major resource that should be developed as soon as possible. Finally, all agreed that the meeting had successfully brought together key leaders in the field and that many new collaborations had been established, and that additional substantial progress in understanding and in treating the glycoproteinoses could be anticipated.

• There should be vigorous support for studies designed to develop mechanisms for the successful delivery of lysosomal enzymes into brain.
• There is a need to further advance new methods of gene therapy delivery into brain.
• Mechanisms need to be developed which will facilitate clinical testing of the development of enzyme replacement or related therapies for the very rare lysosomal diseases (e.g., alpha-mannosidosis).
• Additional support should be provided to encourage further development of collaborations among investigators working on the glycoproteinoses and other lysosomal diseases.
• The use of animal models for exploring issues of pathogenesis and for testing therapies is strongly supported. The need for a genetic knockout model of fucosidosis in mice is notable as one of the key glycoproteinoses still lacking a widely available model.

AGENDA

The Glycoproteinoses: An International Workshop on Advances in Pathogenesis and Therapy
April 1-2, 2004
DoubleTree Hotel and Executive Meeting Center
Rockville, MD

Chairs -- Alessandrad'Azzo (Memphis), Leena Peltonen (Helsinki) and Steven Walkley (NewYork)

Day 1
7:30-8:00	Continental Breakfast available
8:00-8:15	Welcome and Introduction of representatives from NINDS and ORD: Meeting Chairs Welcome from NINDS (Dr. Audrey Penn) and ORD (Dr. Steven Groft) Statement of workshop goals: Meeting Chairs
8:15-10:00	Session 1 -- Glycoprotein Structure and Function and Disorders of Glycoprotein Metabolism (Chair:Harry Schacter, University of Toronto) ] Regulation of Protein Glycosylation (Stuart Kornfeld, Washington University) Lysosomal Metabolism of Glycoproteins (Bryan Winchester, University College, London) Glycoprotein Storage Disorders (Mark Patterson, Columbia University) General Discussion
10:00-10:30	Coffee Break (with poster viewing)
10:30-12:30	Session 2 -- Mechanisms of Disease with Relevance to the Glycoproteinoses (Chair: John Hopwood, Women's and Children's Hospital, Adelaide) Abnormalities in Endocytic Trafficking in Sphingolipidoses (David Marks, Mayo Clinic) Secondary Glycosphingolipid Accumulation and Its Consequences (Steven Walkley, Albert Einstein College of Medicine) Regulation of Chaperone-Mediated Autophagy (Ana Marie Cuervo, Albert Einstein College of Medicine) General Discussion I Microglial Involvement in Brain Pathology in the Mouse Models of MPS IIIB and MPS I (Elizabeth. Neufeld, UCLA) Role of Inflammation in the Neurodegeneration of Sandhoff Disease (Richard Proia, NIDDK, NIH) GM1-ganglioside-mediatedactivation of the Unfolded Protein Response causes neuronal apoptosis in GM1-gangliosidosis (Alessandra d'Azzo,St. Jude's Children's Hospital) General Discussion II
12:30-2:00	LUNCH
2:00-3:30	Session 3 -- Animal Models and Pathogenic Cascades I (Chair: Alessandra d'Azzo, St. Jude's Children's Hospital) Targeted Lysosomal Proteomics (Peter Lobel, Robert Wood Johnson Medical School) The Structure and Function of Lysosomal a -Mannosidase (Ole Kristian Tolersrud, Univeristy of Troms, Norway) a -mannosidosis guinea pig (John Hopwood, Women's and Children's Hospital, Adelaide) a -Mannosidosis- Mouse (Paul Saftig, University of Kiel, Germany) Large animal models of Alpha-and Beta-Mannosidosis (Mark Haskins, University of Pennsylvannia) General Discussion
3:30-4:00	Coffee Break (with poster viewing)
4:00-5:30	Session 4 -- Animal Models and Pathogenic Cascades II (Chair: Steven Walkley, AlbertEinstein College of Medicine) a -fucosidosis dog (John Hopwood, Women's and Children's Hospital, Adelaide) Aspartylglucosaminuria (Anu Jalanko, National Public Health Institute, Helsinki) a -N-Acetylgalactosaminidase Deficiency --Studies in Man and Mouse (Detlev Schindler, University of Wuerzburg, Germany) Sialidosis (Mucolipidosis I)and Galactosialidosis (Alessandra d'Azzo, St. Jude's Children's Hospital) I-Cell Disease and Mucolipidosis III (William Sly, Saint Louis University School of Medicine) General Discussion
6:00-7:00	Poster Discussion (Chairs: Mark Haskin and Richard Proia) Deletion of macrophage-inflammatory protein-1a retards neurodegeneration in Sandhoff disease mice. Yun-Ping Wu and Richard L. Proia Elevated Chitotriosidase Activity in CSF in Patients with GM1-- and GM2--gangliosidosis: A Surrogate Marker of Disease Progression? Cynthia J. Tifft, Joanne Kurtzberg and Richard L. Proia A search for factors leading to neurodegeneration in MPS IIIB mouse model. Kazuhiro Ohmi, Kavitha Rajavel, Hui-Zhi Zhao and Elizabeth Neufeld Canine mucopolysaccharidosis IIIB: Findings in young and aged dogs. N. M. Ellinwood, L. Verot,M.-A. Colle, U. Giger, M. T. Vanier, and M.E. Haskins Sustained therapeutic levels of a -galactosidase A in Fabry miceby neonatal lentivirus gene transfer. Makoto Yoshimitsu, Kesheng Tao, Xiaohu Fan, Lori West, Jeffrey A. Medin Rescue of NEU1 missensemutations: PPCA chaperone therapy for sialidosis. Gouri Yogalingam, Erik Bonten and Alessandra d'Azzo Enzyme replacement therapy of sialidosis and galactosialidosis mouse models. Dongning Wang, Erik Bonten, Linda Mann and Alessandra d'Azzo General Discussion
7:00	Evening Session -- Reception hosted by the International Society for Mannosidosis and Related Disorders (ISMRD) Hors d'oeuvres and cash bar Presentation by Paul Murphy, President, ISMRD
Day 2
8:00-8:30	Continental Breakfast available
8:30-10:00	Session 5 -- Therapeutic Strategies I (Chair :Elizabeth Neufeld, UCLA) Enzyme Replacement Therapy Towards an enzyme replacement therapy in a mouse model for alpha mannosidosis (Paul Saftig, University of Kiel, Germany) Treatment of MPS Brain Disease in Null-Genotyped canines Using Intrathecal Enzyme Therapy and Immune Tolerance (Emil Kakkis, BioMarin Pharmaceuticals, Inc.) Hematopoietic Cell Therapy Hematopietic Cell-Based Transplantation for CNS Therapy in Storage Disorders: Aspects of Microglial-mediated Enzyme Replacement for Neurons (Kostantin Dobrenis, Albert Einstein College of Medicine) Cognitive Outcome of Patients with MPS I after Unrelated Umbilical Cord Transplant (Maria Escolar, Duke University Medical Center) Improvement in Sensorineural Hearing Loss Following Hematopoietic Stem Cell Transplantation (HSCT) in Alpha-Mannosidosis (Charles Peters, University of Minnesota) General Discussion
10:00-10:30	Coffee Break (with poster viewing)
10:30-12:00	Session 6 -- Therapeutic Strategies II (Chair: Bryan Winchester, University College, London)] Stem Cell Therapy --Application to Storage Diseases (Darwin Prockop, Tulane University) Gene Therapy for the Mucopolysaccharidoses (Mark Sands, Washington University) Broad-Scale Implementation of Recombinant Lentiviral Vectors for Gene Therapy of Fabry Disease (Jeffery Medin, University of Toronto) Adeno-Associated Virus Vector-Mediated Gene Transfer to the Brain of Cats with Alpha-Mannosidosis(Charles Vite, University of Pennsylvannia) Gene Therapy for Galactosialidosis (Alessandra d'Azzo,St. Jude's Children's Hospital) General Discussion
12:00-1:00	LUNCH
1:00-3:00	Session 7 -- Summary and Future Directions (Chair: Stuart Kornfeld, Washington University) (Discussants: Mark Haskins, John Hopwood, Dag Malm, Elizabeth Neufeld, Harry Schacter, William Sly, and Danilo Tagle) Pathogenic Mechanisms Animal Models Treatment Strategies Future Research Prioritiesand Research Collaborations Funding Strategies
3:00	Meeting close

Participant List

Workshop Organizers

Dr. Alessandra d'Azzo
Department of Genetics
St. Jude Children's Research Hospital

Dr. Leena Peltonen
UCLA Department of Human Genetics
University of California Los Angeles

Dr. Danilo A. Tagle
Neurogenetics
NINDS, NIH

Dr. Steven U. Walkley
Department of Neuroscience
Rose F. Kennedy Center for Research in Mental Retardation and Human Development
Albert Einstein College of Medicine

Invited Speakers/Session Leaders/Discussants:

Dr. Ana Marie Cuervo
Department of Anatomy andStructural Biology
Albert Einstein College of Medicine

Dr. Kostantin Dobrenis
Department of Neuroscience
Albert Einstein College of Medicine

Dr. Mark Haskins
Department of Pathobiology
Center for Comparative Medical Genetics
School of Veterinary Medicine

Dr. John Hopwood
Dept. of Chemical Pathology
Women's and Children's Hospital

Dr. Emil Kakkis
Bio Marin Pharmaceutical Inc.

Dr. Stuart Kornfeld
Div. of Hematology-Oncology
Dept. of Medicine
Washington University School of Medicine

Dr. Joanne Kurtzberg
Pediatric and Adult Bone Marrow Transplant Programs
Duke University Medical Center

Dr. Peter Lobel
Department of Pharmacology
Robert Wood Johnson Medical School
Center for Advanced Biotechnology and Medicine

Dr. Dag Malm
University Hospital of Northern Norway

Dr. David Marks
Department of Biochemistry and Molecular Biology
Mayo Clinic and Foundation

Dr. J. Medin
Division of Experimental Therapeutics
Ontario Cancer Institute, Toronto, Canada.

Dr. Elizabeth Neufeld
Dept. of Biological Chemistry
UCLA School of Medicine

Dr. Marc Patterson
Division of Pediatric Neurology
Columbia University

Dr. Charles Peters
Inherited Metabolic Storage Disease Program
University of Minnesota

Dr. D. Prockop
Center for Gene Therapy
Tulane University Health Sciences Center

Dr. Richard Proia
Genetics of Development and Disease
National Institutes of Health

Dr. Paul Saftig
Biochemisches Institut
Christian-Albrechts-Universität Kiel

Dr. Mark Sands
Department of Internal Medicine
Washington University School of Medicine

Dr. Harry Schachter
Department of Structural Biology and Biochemistry
The Research Institute
The Hospital for Sick Children

Dr. Detlev Schindler
Director, Cell Culture, Biochemistry and Flow Cytometry Division
Department of Human Genetics
University of Wuerzburg

Dr. William Sly
Dept. of Biochemistry and Molecular Biology
St. Louis University

Dr. Ole Kristian Tolersrud
Department of Medical Biochemistry
Institute of Medical Biology
University of Tromso

Dr. Bryan Winchester
Biochemistry, Endocrinology and Metabolism Unit
Institute of Child Health