gh CELL THERAPY IN OPERATION

Duchenne's muscular dystrophy (DMD) is one of most frequent hereditary sex-linked diseases. Its frequency is about 1:5000 male babies. The DMD is caused by the defective gene of dystrophin that is a structural protein of the muscular cell membrane. Without dystrophin, muscles gradually degrade. They strive to regenerate at the initial stages of the illness, but later this process becomes less and less effective, muscles are substituted by another tissue, and man dies before his twenties as a result of the malfunction of heart and diaphragm (these organs consist of the muscular tissue).

There are several theoretical methods to cure the DMD, but until now they are limited in practice to the experiments on animals. One of these methods implies injecting healthy muscular cells, which produce normal dystrophin, into the muscles of the patients. This method called the cell therapy is connected with significant difficulties, but Russian scientists have surmounted them and conducted first clinical trials in Russia. The experiment was carried out by a team of specialists from the Medical Genetic Research Center of the Russian Academy of Medical Sciences, the Children's Psychoneurological Hospital of the Moscow Region, the Children's Orthopedosurgical Hospital of the Moscow Region, the Institute of Molecular Genetics of the Russian Academy of Sciences, the Hematology Research Center of the Russian Academy of Medical Sciences, and the Moscow Institute of Pediatrics and Pediatric Surgery.

The idea and principles of the cell therapy for curing the DMD are based on the features of human skeleton muscles. They consist mostly of very long cells, myofibrils, containing several tens of nucleuses, as distinct from most human cells with one nucleus. Besides myofibrils, there are some mononuclear cells in skeleton muscles. These cells merge and form new myofibrils as the organism grows. Dividing progenies of mononuclear muscular sells are called myoblasts. Healthy myoblasts transplanted into muscles can merge with myofibrils, and their DNA begins to synthesize a proper distrophin in muscular cells of the patient. The problem is connected with the necessity to produce very high quantities of myoblasts free from other types of cells, which is very difficult to accomplish.

The Moscow scientists spent more than five years developing the technique of myoblast culture growing. The material for the culture was taken from very small specimens of skeleton muscles of patients operated because of injuries and other non-genetic and non-infection ailments. As a result, the scientists drafted the first Russian "Protocol of Conducting the Myoblast Transplantation Following the "One Muscle Curing" Scheme in Case of Duchenne's Myodystrophy" that was approved by the Department for Mother and Baby Health Protection of the Health Ministry of the Russian Federation in the April 1998. Then, in accordance with this program, scientists selected four boys-volunteers with immune characteristics similar to those of donors, whose muscles were used as material for the myoblast cultures. All experiments and their preparation were actively supported by the public association of parents - Interregional Association of Foundations for Assistance to the Sick from Neuromuscular Ailments called "Nadezhda" (that means 'hope').

The operation was performed under a general anaesthetic within only 10-15 minutes. Myoblast cells were injected into the frontal muscle of the right shin by 8-10 shots. An equivalent volume of the physiological solution was injected into the left leg. After the operation, patients complained about a moderate pain in shin muscles, especially in the right one, but these unpleasant feelings disappeared in two days. Before and after the operation, patients were observed at the stationary and treated with immunodepressants. The patients were examined in six months, and the DNA of dystrophin was found in right muscles of all four boys. Tests for the presence of the protein distrophin were done for only two patients because of organizational problems, but in both cases it was found. Muscles of the left leg treated with the physiological solution contained neither DNA nor protein.

The cell therapy method developed by the Russian scientists provides the activity of the dystrophin gene in the muscles of patients within half a year, and this is a great achievement. The next challenge now is to give patients a real relief by means of the transplantation.

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