Urinary channels from stem cells
Six years after transplantation, the urethras (urinary channels) grown from their own cells function normally and allow five boys to lead a normal lifestyle.
The cause of damage to the urethra can be injuries, diseases and congenital anomalies. The restoration of minor defects of this organ does not cause much difficulty, whereas in more severe cases, a graft is required, usually made from the skin or mucous membrane of the inner surface of the cheek. Unfortunately, in more than 50% of cases, such operations fail.
In the period from March 2004 to July 2007, researchers at Wake Forest University, working under the guidance of Dr. Anthony Atala, known for his outstanding achievements in regenerative medicine, transplanted five boys aged 10 to 14 years sections of the urethra grown from their own cells.
In three patients, the urethra was damaged as a result of extensive pelvic injuries, and two had a history of earlier unsuccessful transplants of this organ. As a result, the boys were forced to lead a sedentary lifestyle due to the need to constantly carry bags with them to collect urine excreted using a catheter, which is extremely inconvenient, painful and associated with the risk of infection of the genitourinary system.
A small (approximately 1x1 cm) fragment of bladder tissue was taken from each of the patients, from which smooth muscle and endothelial cells were isolated. For 3-6 weeks, the cells were cultured in the laboratory, after which they were applied to the surface of a three-dimensional frame in the form of a urethra. The frames, the dimensions of which were selected individually for each patient, were made of biodegradable cellular material. The prepared scaffolds were incubated for 7 days, which allowed the cells to completely cover their surface. As a result, the total duration of graft production ranged from 4 to 7 weeks.
At the end of incubation, the skeletons populated with cells were surgically implanted into the places of the removed defective fragments of the urethra. In the conditions of the organism, the cells continued to actively divide. Biopsies performed three months after the operation showed that the newly formed areas of the urethra consisted of normal layers of epithelium and smooth muscles. According to the results of subsequent examinations and interviews of patients, the transplantation allowed them to return to an absolutely normal lifestyle.
The report on the work (Tissue-engineered autologous urethras for patients who need reconstruction: an observational study) is published in the Lancet journal.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Wake Forest University Baptist Medical Center:
Laboratory-Grown Urethras Implanted in Patients, Scientists Report
09.03.2011