Two year old receives artificial stem cell-based trachea
A two-year-old girl, who was born in South Korea in 2010 without a windpipe, has implanted doctors from the Children's Hospital of Illinois (USA) with an artificial windpipe made of synthetic fibers that has been covered with blood stem cells from the child's bone marrow. Media around the world saw this as promising news from stem cell research. But there remain doubts about the meaningfulness and the suggested long-term healing success.
Little Hannah Warren was born in Seoul in August 2010 to a Canadian father and a Korean mother. When the two-year-old saw the light of day, her entire body turned blue due to the lack of oxygen. Hannah suffered from the extremely rare tracheal agenesis, she missed the windpipe. Doctors had to act quickly to save the child's life. They put a tube in her throat through which her lungs could be oxygenated. More specifically, the tube ran through the esophagus and was passed from there into the lungs. In order to prevent gastric acid from flowing back into the lungs, the doctors closed the esophagus towards the stomach and the girl was put a gastric tube directly into her stomach, through which she could be fed. From the beginning, however, it was clear that Hannah would not be able to survive in this state in the long run.
Ethical controversy about surgery In the case of little Hannah, the US medical doctor Dr. Mark Holterman, professor at the University of Illinois College of Medicine in Peoria. He drew the renowned stem cell researcher Dr. Paolo Macchiarini from the Karolinska Institute in Stockholm (Sweden), who had previously implanted stem cell-based artificial hollow organs. For the first time, the doctors wanted to try out the new technology on a two-year-old girl. After the necessary funds could be raised, intensive ethical discussions followed, since Hannah also acted as a guinea pig and her parents understandably reached for every straw given the child's seemingly hopeless situation. The ethical conflicts of stem cell research in general were also discussed due to the use of stem cells to colonize the artificial hollow organ. However, since the stem cells were obtained from the child's bone marrow, these concerns were quickly resolved.
Two-year-olds can breathe and taste normally for the first time. Ultimately, all the responsible institutions gave their consent and the girl was put through the plastic trachea covered with stem cells a month ago in the Children's Hospital of Illinois during an operation lasting several hours. At first, the ambitious medical project seems to have been a success. The child can breathe and theoretically eat normally for the first time in his life, although extreme restraint has so far been observed here. The little girl was only allowed to try a lollipop. With solid food, she may have to wait some time. Because the doctors also discovered vocal cords in the girl during her examinations, they hope that Hannah may even learn to speak over the years.
Doubts about the medical advantages of the new procedure An overall convincing result, if it weren't for the doubts about the durability of the artificial trachea and the possible risks. Because two of the few adult patients who have been operated on with the method have died for no apparent reason and in one patient the artificial hollow organ has proven to be unstable. Basically, the question also arises whether this new treatment method has a medical advantage over the previously used trachea transplantation of deceased donors. Availability can be mentioned here as a clear plus point of stem cell-based artificial hollow organs, but the safety of therapy actually seems higher with the conventional method. However, a donor organ does not grow with children, so that in case of doubt they also need a new operation or transplant. How the life of the little Hannah will go remains open for the time being due to the imponderables, but looking back at the past 32 months since her birth, an improvement can be expected. (fp)
Image: Martin Büdenbender / pixelio.de