Evaluation And Comparison Of Lentiviral And AAV Vector Mediated Gene Therapy For The Mucopolysaccharidoses
Funder
National Health and Medical Research Council
Funding Amount
$521,320.00
Summary
The mucopolysaccharidoses are a group of inherited diseases that have profound consequences for affected individuals. They have pleiotropic effects and usually result in premature death. Although intravenous enzyme replacement therapy has been developed for a number of these disorders, this approach to therapy is invasive, very expensive, of limited efficacy, and is completely ineffective in treating brain pathology. The principal reason for this is the protected nature of the brain which preven ....The mucopolysaccharidoses are a group of inherited diseases that have profound consequences for affected individuals. They have pleiotropic effects and usually result in premature death. Although intravenous enzyme replacement therapy has been developed for a number of these disorders, this approach to therapy is invasive, very expensive, of limited efficacy, and is completely ineffective in treating brain pathology. The principal reason for this is the protected nature of the brain which prevents enzymes that are administered intravenously from entering. Therefore, alternative therapies must be considered in order to provide more effective therapy for the mucopolysaccharidoses, especially those that have significant brain pathology. Gene therapy is one such alternative therapy but this still faces the problem of introducing the therapeutic agent (in this case the gene encoding the requisite enzyme) into the brain. This project aims to provide a comparitive evaluation of two gene therapy vectors for their efficacy in treating all aspects of the pathology found in the mucopolysaccharidoses. Both vectors have the properties of being able to efficiently deliver genes to different cell types and result in the stable genetic modification of the target cell, making them ideal for long-term treatment. However, for effective gene therapy, significant and widely distributed gene delivery to the brain, as well as to other tissues, will be required. This project aims to compare the efficacy of these vectors in two different animal models of the mucopolysaccharidoses that exhibit a wide range of the clinical problems associated with these diseases, importantly including brain pathology.Read moreRead less
Treatment Of Lysosomal Storage Disorder Patients By Drug-enhanced Premature Stop Codon Read-through
Funder
National Health and Medical Research Council
Funding Amount
$431,764.00
Summary
Lysosomal storage disorders are a devastating set of genetic diseases with very severe clinical symptoms. In this project, we will investigate a new treatment strategy that is non-invasive and that will be applicable for a wide range of lysosomal storage disorder patients. The therapy will over-ride the molecular genetic lesion and will be preferentially targeted for patients who are at the severe end of the clinical spectrum, where treatment options are currently limited.
Mucopolysaccharidoses (MPS) are a related group of 11 debilitating genetic disorders affecting children. They result from a reduction or total deficiency of an enzyme required for the removal of carbohydrate structures called glycosaminoglycans (gags). Gag degradation occurs inside the cell in specific organelles termed lysosomes and in the absence of the appropriate enzyme, undegraded gag accumulates in the cell. This leads to a range of clinical symptoms and multiple tissue failure. Symptoms c ....Mucopolysaccharidoses (MPS) are a related group of 11 debilitating genetic disorders affecting children. They result from a reduction or total deficiency of an enzyme required for the removal of carbohydrate structures called glycosaminoglycans (gags). Gag degradation occurs inside the cell in specific organelles termed lysosomes and in the absence of the appropriate enzyme, undegraded gag accumulates in the cell. This leads to a range of clinical symptoms and multiple tissue failure. Symptoms common to more than one MPS type include mental deterioration, blindness, abdominal organ enlargement and bone growth problems leading to short stature and bone loss. My laboratory has had a long-term interest in developing treatment for MPS and our research led to the clinical implementation of enzyme replacement therapy (ERT) for MPS VI in 2005. While providing the first effective, multi-tissue treatment for MPS, our research showed that several tissues were not responsive to ERT. These are the brain, cartilage and cornea, thus children on ERT regimens will still suffer from mental retardation, arthritis and blindness. With the goal of treating these particular tissues we have developed a new approach to MPS therapy called substrate deprivation therapy (SDT). Instead of adding back the missing enzyme, SDT acts by decreasing gag production which in turn reduces the level of accumulated gag in cells. SDT results in the correction of MPS cells in culture and reduces several key clinical symptoms in the mouse model of MPS IIIA. In this proposal we will extend our research to evaluate the effect of SDT on brain and bone-joint pathology. Evaluation of efficacy will take place in the MPS VII mouse which exhibits both brain and bone disease and in a new model of MPS IVA developed specifically for this study which exhibits a joint pathology unique amongst the MPS disorders.Read moreRead less
PROTEIN PROFILING FOR THE IDENTIFICATION AND MONITORING OF LYSOSOMAL STORAGE DISORDERS AND OTHER NEUROLOGICAL DISEASES
Funder
National Health and Medical Research Council
Funding Amount
$469,500.00
Summary
Lysosomal storage disorders (LSD) are a group of more than 45 progressive genetic diseases, that result from the absence or impaired function of a specific enzyme in each of the body's cells. Lysosomes rid the cell of excess waste. Impaired enzyme function halts this process and waste begins to accumulate (or 'store') in the cell. Disease severity and patient longevity is variable, but severely affected patients often die by their mid-teens. LSD can affect the skeleton and joints, respiratory an ....Lysosomal storage disorders (LSD) are a group of more than 45 progressive genetic diseases, that result from the absence or impaired function of a specific enzyme in each of the body's cells. Lysosomes rid the cell of excess waste. Impaired enzyme function halts this process and waste begins to accumulate (or 'store') in the cell. Disease severity and patient longevity is variable, but severely affected patients often die by their mid-teens. LSD can affect the skeleton and joints, respiratory and cardiovascular systems, the brain, the eyes, the ears and the airways. As affected children become older, symptoms worsen. Patients often require frequent hospitalisation, and medical and surgical intervention. Approximately 10 to 15% of the general population are affected or carriers of an LSD. In Australia, one LSD child is born in every 5,000 live births. Diagnosis often takes several years, and families often have other children before their affected child is diagnosed. LSD are, therefore, a considerable burden to not only the families but also to the health care system. The goal of the Lysosomal Diseases Research Unit is Diagnosis at birth and effective therapy for lysosomal storage disorders. To this end we have been working toward the development of a newborn screening program for LSD and improved methods for the diagnosis and monitoring of therapy in this group of diseases. In this project we propose to develop and evaluate the use of protein profiling (looking at many diagnostic markers at the same time) to achieve these goals. The technology developed in this project will have potential application beyond LSD. Lysosomal dysfunction has been implicated in Alzheimer's disease and Parkinson's disease; in addition lysosomal proteins are reported to be involved in the spread of some cancers and may be useful markers for early detection. We will collaborate with other research groups to further develop protein profiling in these areas.Read moreRead less
Canine Adenovirus-mediated Gene Therapy For CNS Pathology In LSD
Funder
National Health and Medical Research Council
Funding Amount
$490,029.00
Summary
Lysosomal storage disorders (LSD) are inherited diseases that affect about 1 in 7700 Australian children; all share common physical symptoms include heart and breathing difficulties, stiff joints, skeletal deformities, enlarged head, and a characteristic facial appearance. Two-thirds of patients will also develop brain disease. The lysosome is a component of each cell in the human body; its role it is to break down and remove waste from the cell. This involves a series of proteins (enzymes) that ....Lysosomal storage disorders (LSD) are inherited diseases that affect about 1 in 7700 Australian children; all share common physical symptoms include heart and breathing difficulties, stiff joints, skeletal deformities, enlarged head, and a characteristic facial appearance. Two-thirds of patients will also develop brain disease. The lysosome is a component of each cell in the human body; its role it is to break down and remove waste from the cell. This involves a series of proteins (enzymes) that act in sequence. A LSD arises when the lysosome lacks the activity of one protein in this chain. This loss of protein activity means that the waste removal process is impaired. Waste begins to 'store' in the lysosome, clogging the cell and interfering with its usual functions. This gives rise to devastating symptoms that worsen over time as storage increases. Brain disease in LSD has profound effects on the child: mental capacity declines, they become hyperactive and aggressive and progressively lose learned skills (e.g. walking, talking) and control of bodily functions. Artifically made protein is being successfully used to treat some LSD via intravenous injection. However, it cannot access the brain because of a protective barrier that surrounds it. Gene therapy is a method by which we are attempting to overcome this problem. By using a virus called canine adenovirus (or CAV), we plan to produce and insert the missing protein into mice who are deficient in it. CAV will be the protein carrier. CAV is safe in humans and does not have many of the problems associated with some other viruses being tested in gene therapy. We have diagnosed mice who are naturally affected by a LSD with brain disease called MPS IIIA. Their symptoms are similar to that seen in humans, making them ideal for study. CAV vectors are being considered as a long-term treatment for patients who suffer from MPS IIIA and other degenerative brain diseases.Read moreRead less
Skeletal disease is a major problem for children with mucopolysaccharidoses (MPS). Patients suffer from early onset osteoporosis and osteoarthritis, severely affecting their quality of life. We will evaluate a lentiviral gene therapy vector developed in-house for its capacity to transduce bone, cartilage, synovial and ligament cells in a mouse model of MPS VI. Our goal is to generate high level, sustained expression of the deficient MPS enzyme and alter the course of skeletal disease in MPS.
Cisterna Magna Delivery Of Therapeutic Lysosomal Enzyme To Correct CNS Pathology In Lysosomal Storage Disorders
Funder
National Health and Medical Research Council
Funding Amount
$760,282.00
Summary
Lysosomal storage disorders (LSD) are inherited diseases that affect about 1 in 7700 Australian children; all share common physical symptoms include heart and breathing difficulties, stiff joints, skeletal deformities, enlarged head, and a characteristic facial appearance. Two-thirds of patients will also develop brain disease. The lysosome is a component of each cell in the human body; its role it is to break down and remove waste from the cell. This involves a series of proteins (enzymes) that ....Lysosomal storage disorders (LSD) are inherited diseases that affect about 1 in 7700 Australian children; all share common physical symptoms include heart and breathing difficulties, stiff joints, skeletal deformities, enlarged head, and a characteristic facial appearance. Two-thirds of patients will also develop brain disease. The lysosome is a component of each cell in the human body; its role it is to break down and remove waste from the cell. This involves a series of proteins (enzymes) that act in sequence. A LSD arises when the lysosome lacks the activity of one protein in this chain. The loss of protein activity impairs the waste removal process. Waste begins to 'store', clogging the cell and interfering with its usual functions. This gives rise to devastating symptoms that worsen over time as storage increases. Brain disease in LSD has profound effects on the child: mental capacity declines, they become hyperactive and aggressive and progressively lose learned skills (e.g. walking, talking) and ability to control bodily functions. Artifically made protein is being successfully used to treat some LSD via intravenous injection. However, it is not able to access the brain because of a protective barrier that surrounds it. This project tests a method to deliver protein to the brain to reduce and stop waste build-up. It involves the injection of artificially made protein into the fluid surrounding the brain and spinal cord using techniques being used to treat other diseases. This method is likely to be the quickest way in which we can treat both the body AND the brain of an affected child. We have diagnosed animal models who were born with a LSD with brain disease, called MPS IIIA. Their symptoms are similar to that seen in humans over the course of the disease, making them ideal for study in this project. Success in this project will allow us to advance this treatment to human trials.Read moreRead less
Development Of A Safe And Effective Treatment For Neuropathology In MPS IIIA.
Funder
National Health and Medical Research Council
Funding Amount
$665,320.00
Summary
MPS IIIA is an inherited disorder that results in progressive brain disease in affected children. The disorder cannot be treated at present because it has not been possible to find an effective way to deliver treatment to the brain. This project seeks to evaluate a method to overcome this problem. Findings in this project can be applied to other, similar disorders that affect the brain.
MECHANISMS OF PATHOLOGY AND NEW THERAPEUTIC OPTIONS FOR GAUCHER DISEASE AND OTHER LIPIDOSES
Funder
National Health and Medical Research Council
Funding Amount
$439,500.00
Summary
The sphingolipidoses are a subgroup of the more than 45 genetic disorders known collectively as lysosomal storage disorders (LSD). As a result of the deficiency of specific enzymes or proteins involved in the breakdown of sphingolipids (fats), there is an accumulation of this material in affected cells. These diseases can affect liver, spleen, kidney, bone and the central nervous system. Gaucher disease is the prototype for the sphingolipidoses and, in this project, we will use this disease as a ....The sphingolipidoses are a subgroup of the more than 45 genetic disorders known collectively as lysosomal storage disorders (LSD). As a result of the deficiency of specific enzymes or proteins involved in the breakdown of sphingolipids (fats), there is an accumulation of this material in affected cells. These diseases can affect liver, spleen, kidney, bone and the central nervous system. Gaucher disease is the prototype for the sphingolipidoses and, in this project, we will use this disease as a model for this group of disorders. Gaucher disease in the most prevalent LSD with an incidence of 1:56,00 births, worldwide there are approximately 2300 affected individuals born each year. Enzyme replacement therapy (ERT) for Gaucher disease has been successful in the treatment of the non-neuropathic form of the disease. However ERT is expensive ($200,000-400,000 pa). There are approximately 50 Australian patients undergoing ERT at a cost of at least $10 million per annum. However, due to the high cost of treatment, many people do not qualify for ERT, despite having serious medical problems. Worldwide, there are approximately 4000 people currently receiving ERT for Gaucher disease at a total drug cost of over $1.0 billion pa. However, based on birth rates and life expectancies there are over 80,000 Gaucher patients in the world. With the current cost of ERT it is likely that over 90% of these will never receive ERT. If therapy is to be made available for the majority of affected individuals, cheaper alternatives will be required. In this project we will use cellular models of Gaucher disease to study the processes leading to the disease and to develop alternative, cheaper therapies for this disease and other types of sphingolipidoses, for which no therapies currently exist.Read moreRead less
Therapy For CNS Degeneration In MPS Disorders That Targets Both Glycosaminoglycan And Ganglioside Storage.
Funder
National Health and Medical Research Council
Funding Amount
$368,043.00
Summary
Children with seven of the eleven types of mucopolysaccharidosis (MPS) disorders exhibit a profound, irreversible neurological deterioration that manifests in infancy. This results from the continual buildup of undegraded sugar and fat in brain cells. The goal of this proposal is to prevent the accumulation of lipid alone or both lipid and sugar in the brain in order to alter the progression of neurological disease. Treatment will be assessed in mouse models of MPS.