RNA Interference And Retigabine Therapy Protect Against Hereditary Hearing Loss
Funder
National Health and Medical Research Council
Funding Amount
$370,522.00
Summary
The preservation of hearing function is central to the treatment of individuals who are genetically predisposed to hearing loss. At present only synthetic hearing aids and cochlear implants can provide functional improvement, albeit sub-optimal. The studies described here will seek to prevent hearing loss by reducing the damaging effects of defective genes. Gene therapies that reduce the effect of these defective genes and a drug that enhances the activity of functional genes will be developed.
Dystrophin Gene Repair In Mdx Mouse Myoblasts And Bone Marrow Cells As A Basis For Autologous Transplant In Human DMD
Funder
National Health and Medical Research Council
Funding Amount
$422,036.00
Summary
The muscular dystrophies are inherited diseases that lead to muscle wastage and severe disabilities. The most severe forms result in the early death of newborns, but a large number are diagnosed in children showing early mild symptoms and progress steadily to severe disabling forms in the juvenile and young adult. Perhaps the most devastating of these dystrophies is Duchenne Muscular Dystrophy (DMD). This condition affects 1 in 3,300 boys, who show symptoms at around 5 years of age until wheelch ....The muscular dystrophies are inherited diseases that lead to muscle wastage and severe disabilities. The most severe forms result in the early death of newborns, but a large number are diagnosed in children showing early mild symptoms and progress steadily to severe disabling forms in the juvenile and young adult. Perhaps the most devastating of these dystrophies is Duchenne Muscular Dystrophy (DMD). This condition affects 1 in 3,300 boys, who show symptoms at around 5 years of age until wheelchair confinement by early teens. DMD boys undergo major clinical and surgical treatments which at present only provide small but significant improvements to their lives. The median age at death for Duchenne boys is 22 years. The cause of DMD has been known for almost 2 decades and is a defect in just a single component of muscle, Dystrophin which is produced by muscle cells. In general, boys with DMD possess Dystrophin which is missing an important part that prevents the breakdown of muscles during activity. As a consequence, all the muscles in DMD boys slowly break down over their lifetime until they die because the muscle which helps in drawing breath (Diaphragm) is no longer capable of helping them to breathe. The muscle component Dystrophin is produced by a gene (the dys gene) and the defect of Dystrophin is caused by a defect in the dys gene. If the dys gene defect was able to be corrected in boys with DMD, their Dystrophin may also be corrected and the breakdown of their muscle prevented. We have been able to correct the dys gene in muscle cells from a mouse with DMD. We wish to improve this technology and allow muscle to be repopulated with genetically corrected cells to form a basis for treatment of human DMD. In this way we hope to significantly improve and lengthen these boys' lives and even lead to a cure for DMD and other genetic muscle diseases.Read moreRead less
Customized IPS Cell Therapy For Recessive Monogenic Retinal Degenerative Disease
Funder
National Health and Medical Research Council
Funding Amount
$350,714.00
Summary
The focus of this study is to develop a personalised treatment for certain types of retinal degenerative disease (RDD). Stem cells will be generated from the skin cells obtained from an individual with RDD. Gene therapy will then be applied to correct the underlying disease-causing mutation in the patient cells. The repaired cells will be used to generate retinal cells, which will subsequently be tested in naturally occurring RDD rodent models to determine if they have any beneficial effects.
Development Of Lentiviral Vectors For The Treatment Of X-linked Severe Combined Immunodeficiency (SCID-X1)
Funder
National Health and Medical Research Council
Funding Amount
$71,434.00
Summary
The first successful gene therapy clinical trial was reported in 2000 with the treatment of X-linked severe combined immunodeficiency (SCID-X1), commonly known as “bubble-boy” disease. The subsequent development of leukaemia in 3 of 11 patients has prompted the need to develop alternative vectors for gene delivery, such as HIV-1-based lentiviral vectors. This project will evaluate the efficacy and safety of lentiviral vectors in vivo, and hence their therapeutic potential for treating SCID-X1.
A FACS-based Screen For Retroviral Silencing: A Tool For Detecting Trans-sensing In Mammalian Cells
Funder
National Health and Medical Research Council
Funding Amount
$205,010.00
Summary
Retroviruses are RNA viruses that infect cells and then become integrated into the genome of the infected cell. This property has been exploited in attempts to cure genetic diseases by replacing the defective gene: the replacement can be incorporated into the retrovirus, transported into a cell, and become part of the cell?s genetic material. However, retroviruses are frequently suppressed by the host cell some time after integration, so that their genetic information becomes silent. The factors ....Retroviruses are RNA viruses that infect cells and then become integrated into the genome of the infected cell. This property has been exploited in attempts to cure genetic diseases by replacing the defective gene: the replacement can be incorporated into the retrovirus, transported into a cell, and become part of the cell?s genetic material. However, retroviruses are frequently suppressed by the host cell some time after integration, so that their genetic information becomes silent. The factors that cause silencing of retroviruses are not well understood, but it is clear that this problem is a major impediment to retrovirus-based (and perhaps all) gene therapies. In a wide variety of organisms, including plants, flies, and yeast, it has been found that multiple copies of a gene can silence each other, a phenomenon termed cosuppression. Some reports suggest that this might happen in mammals as well. We have initiated a study of retroviral silencing, using a marker protein that produces green fluorescence as a model for the replaced gene. We find that the gene is usually silenced after integration, immediately or over time, but can be reactivated by drugs that demethylate DNA or alter chromosomal structure. We now propose to extend this work by doing a systematic analysis of the frequency of retroviral silencing in human T cells, and then to develop a system to detect and analyze cosuppression by retroviruses. This work will rely on the ability of fluorescence-activated cell sorting (FACS) to detect rare events in a large population of cells, and recover those rare cells. We will also test methods of destabilizing the silent state of a retrovirus. These experiments are likely to yield information that will benefit a broad array of gene replacement efforts. A demonstration of cosuppression would be particularly interesting because of the possibility that endogenous elements in the mammalian genome are regulated by this mechanism.Read moreRead less
Cell-targeted Gene Delivery Into Human Haematopoietic Stem Cells For The Treatment Of Thalassaemia
Funder
National Health and Medical Research Council
Funding Amount
$171,208.00
Summary
Thalassaemia is the most common inherited single gene disorder affecting haemoglobin synthesis in red blood cells. It mainly affects people of Mediterranean, Middle Eastern, African, South East Asian, Chinese, and Indian origin. However, large numbers of thalassaemia patients are found nowadays in Australia and other developed countries, due to large population movements in the twentieth century. Approximately 300,000 severely affected children are born each year with thalassaemia and various ot ....Thalassaemia is the most common inherited single gene disorder affecting haemoglobin synthesis in red blood cells. It mainly affects people of Mediterranean, Middle Eastern, African, South East Asian, Chinese, and Indian origin. However, large numbers of thalassaemia patients are found nowadays in Australia and other developed countries, due to large population movements in the twentieth century. Approximately 300,000 severely affected children are born each year with thalassaemia and various other abnormalities of haemoglobin synthesis. If untreated, most thalassaemia patients will die within the first few years of life. The vast majority of thalassaemia patients depend on regular blood transfusions every two to three weeks, and on nightly infusions of an iron chelator (a drug for removing excess iron from the blood). These procedures place considerable burden on thalassaemia patients, their families and society, and expose them to blood transmitted infections. The only curative treatment for thalassaemia is bone marrow transplantation from a matching donor. However, the vast majority of patients do not have matching donors and thus the only prospect for them to receive such therapy is to replace in their bone marrow cells a copy of the normal set of genes for the synthesis of haemoglobin. The studies in this proposal are therefore designed to test gene therapy protocols on bone marrow stem cells derived from thalassaemia patients. A normal set of globin genes will be delivered to the bone marrow stem cells via non-viral delivery systems and examined for function in an immunodeficient mouse strain that can accept human bone marrow. This research may enable bone marrow transplantation to be applied for the therapy of most patients with thalassaemia, while it may also have a major impact on therapeutic approaches for other haematological anomalies.Read moreRead less
Induction Of Antigen-specific Humoral Tolerance By RAAV-mediated Delivery Of CTLA4-Ig-antigen Fusion Molecules
Funder
National Health and Medical Research Council
Funding Amount
$524,456.00
Summary
There are many medical situations where immune suppression is required. Available methods lack specificity and risk infection, drug-related side-effects and cancer. We have discovered a novel way of suppressing immunity such that only unwanted responses are eliminated. This involves virus-mediated delivery of antigen fused to CTLA4-Ig. We plan to test this strategy in the context of gene therapy, to work out how it works and to optimise the approach. Success will have broad health implications.
Gene therapy is a novel form of medical treatment in which healthy genes are used to replace defective genes in cells. It is sobering to realise that in the next few years the whole human DNA sequence will be known. Consequently the already large list of genes which are known to cause disease will be greatly expanded through the application of molecular genetics. Surprisingly, however, treatments based on the correction of disease genes in the cells of a patient are not keeping up with expectati ....Gene therapy is a novel form of medical treatment in which healthy genes are used to replace defective genes in cells. It is sobering to realise that in the next few years the whole human DNA sequence will be known. Consequently the already large list of genes which are known to cause disease will be greatly expanded through the application of molecular genetics. Surprisingly, however, treatments based on the correction of disease genes in the cells of a patient are not keeping up with expectations. In attempting to achieve clinically relevant results, viruses (masters of forcing infected cells to do their bidding) have been harnessed to deliver healthy genes into diseased cells. The problem has been that the modified, safe viruses used clinically have not been efficient at achieving sustained production of healthy genes in sufficient numbers of cells. In the studies described , we will attack this problem using a number of different, but complementary approaches. Our main focus will be to facilitate efficient virus entry of appropriate target cells. We have recently been successful in cloning the receptors for two important viruses which can enter human cells. Identification of these receptors gives us clues to methods of improving virus entry. Now that we know the identity of these receptors, we can create tools to define the type of cells that these viruses can readily target.Read moreRead less