Can gene therapy cure children with severe hereditary diseases?
It is well known that low bone density leads to osteoporosis and an increased risk of fractures. However, too high bone density is also dangerous for the body. The most serious form of this pathology is a rare hereditary disease – congenital malignant systemic osteopetrosis (marble disease).
In this disease, the balance between the activity of cells that form and destroy bone tissue is disturbed. The defective functioning of bone-destroying osteoclasts leads to overgrowth of the natural bone cavities in which the bone marrow and nerves are located. Compression of the optic and auditory nerves causes deafness and blindness in such patients, and the inability of the bone marrow to function causes death from anemia and infections, usually in infancy. In Europe, this disease is diagnosed in 1 out of 300,000 newborns, and the highest incidence is in Costa Rica, where 3-4 out of 100,000 children are born with osteopetrosis.
To date, the disease is treated only by bone marrow transplantation, which in itself is a very risky procedure, which is possible only if there is a suitable donor.
Swedish researchers from Lund University decided to approach this problem from a different angle. They have developed a gene therapy method that does not require the introduction of donor hematopoietic cells. The essence of the new method is to isolate the patient's own stem cells and replace the non-functional TCIRG1 gene in their genome, encoding a subunit of the proton pump necessary for bone resorption, with its full-fledged copy.
The experimental method was tested on cells of patients with congenital malignant systemic osteopetrosis and on a mouse model of the disease. The next stage will be a clinical trial, which is planned to be conducted at a clinic in Ulm, Germany, specializing in the treatment of children with this disease.
At the present stage, gene therapy is not without serious risks. Specialists do not have the ability to embed a therapeutic gene in a strictly defined place of the genome, and its embedding in the wrong region can lead to the development of a malignant tumor. Therefore, in the foreseeable future, gene therapy will be used exclusively for severe diseases for which no effective treatment methods have been developed.
The defense of Carmen Flores Bjurstroem's dissertation “Targeting the hematopoietic stem cell to correct osteopetrosis”, written on the basis of the research results, took place on September 6 at Lund University. The work was carried out under the supervision of Professor Johan Richter.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Lund University:
Can gene therapy cure fatal diseases in children?14.09.2012