Gene Therapy Done By: Abeer Al-Taweel Albatool Bin Ajlan Amal Alblwi Atheer Hakami Rawan Almugbel Shaikha Aldukhail Supervised by: Dr. Amina Alshibani
Definition What is Gene therapy? • It is an experimental technique that uses genes to treat or prevent disease. In the future, this technique may allow doctors to treat a disorder by inserting a gene into a patient’s cells instead of using drugs or surgery. Researchers are testing several approaches to gene therapy, including: • Replacing a mutated gene that causes disease with a healthy copy of the gene. • Inactivating, or “knocking out,” a mutated gene that is functioning improperly. • Introducing a new gene into the body to help fight a disease.
Types Types Of Gene Therapy • Germ Line gene therapy. • Somatic Gene Therapy.
Applications Gene Therapy Applications: • Before gene therapy can be used to treat a certain genetic condition or disorder, certain requirements need to be met: • The faulty gene must be identified and some information about how it results in the condition or disorder must be known so that the vector can be genetically altered for use and the appropriate cell or tissue can be targeted. • The gene must also be cloned so that it can be inserted into the vector. • Once the gene is transferred into the new cell, its expression (whether it is turned on or off) needs to be controlled. • There must be sufficient value in treating the condition or disorder with gene therapy - that is, is there a simpler way to treat it?
Count’ • The balance of the risks and benefits of gene therapy for the condition or disorder must compare favorable to other available therapies. • Sufficient data from cell and animal experiments are needed to show that the procedure itself works and is safe. • Once the above are met, researchers may be given permission to start clinical trials of the procedure, which is closely monitored by institutional review boards and governmental agencies for safety.(1)
Count’ 1-cancer: • There are different possibilities which can be used to treat cancer with gene therapy; • Genes can be inserted into the cancerous cells so that they become sensitive and can be destroyed with chemotherapy. • genes can be inserted into the cancer cells, they will release toxin which will completely disable them to function in a negative way. • Genes can also make the cancerous cells unstable. Usually cancer cells do not allow the faulty DNA to repair which results in the rapid growth of abnormal cells. • As cancer is caused due to the mutations in the genes, that is why if healthy genes are added in place of abnormal or missing genes, they will start working in a normal way. • Gene therapy can make immune system so strong that it can easily recognize the cancerous cells in the body and completely destroy them
Count’ 2-down syndrome: • Recent findings indicate that gene therapy strategies-based on the introduction of genetic elements by means of delivery vectors-toward the correction of phenotypic abnormalities in DS are also very promising tool to identify HSA21 and non-HSA21 gene candidates, contributing to DS phenotype.
Count’ 3-AIDS: • scientists in California show that a single injection — which inserted the DNA for an HIV-neutralizing antibody into the muscle cells of live mice — completely protected the animals against HIV transmission.
Count’ 4 -Cystic fibrosis: • Gene therapy involves the transfer of correct copies of cystic fibrosis transmembrane conductance regulator (CFTR) DNA to the epithelial cells in the airways.
Count’ 5- Diabetes Mellitus 1: • In Canada, researchers developed a protocol to treat type I diabetes. Doctors use ultrasound to guide a small catheter through the upper abdomen and into the liver. Pancreatic islet cells are then injected through the catheter into the liver. In time, islets are established in the liver and begin releasing insulin.
Count’ 6- Sjogren’s syndrome (SS) : • SS is characterized by the presence of a focal lymphoid cell infiltration in the salivary and lacrimal glands,. • In the absence of any suitable conventional treatments, they have suggested that gene therapy may be beneficial for SS patients. They have hypothesized that transfer of immunomodulatory genes into SGs may reduce the autoimmune sialadenitis and lead to increased salivation as well as symptomatic relief. For example, the transfer of genes encoding anti-inflammatory cytokines such as interleukin-10 (IL-10) or vasoactive intestinal peptide could lead to a decrease in the expression of proinflammatory cytokines, and thus, protect SGs and preserve their secretory function.
Count’ 7- X-linked severe combined immunodeficiency (X-SCID): • It's a disease where a baby lacks both T and B cells of the immune system and is vulnerable to infections. • The current treatment is bone marrow transplant from a matched sibling, which is not always possible or effective in the long term. • most children die from infection in their first two years of life. • One exception was David Vetter, a Texas boy born in 1971. Vetter lived in a specially constructed sterile plastic bubble from birth until his death at age 12 He became famous as the “bubble boy,” and his story made many people aware of SCID for the first time.
Count’ • Nine years after getting gene therapy for a rare, inherited immune system disorder often called “bubble boy disease,” 14 out of 16 children are doing well, researchers report. • The 16 children with SCID who got the gene therapy ranged in age from 6 months to 3 years. Four of them had the ADA-deficiency type of SCID. The other kids had the X1 form of SCID. Those are the two most common types of SCID. • One problem occurred at that time ! • For most of the children, gene therapy was a success. But one boy who had the X1 form of SCID developed treatment-related Leukemia. • The clinical trials were put on hold until a safer method can be designed and tested.
Future W. French Anderson Future Of Gene Therapy “Indeed, within 20 years, I expect that gene therapy will be used regularly to ameliorate —and even cure — many ailments.” • First FDA-approved gene therapy for cancer may be on its way ! Advexinis being studied in the third phase of the trials that are enrolling patients with recurrent, refractory head and neck squamous cell carcinoma. • Gene therapy may reverse congenital hearing loss.