Reading a box outside the body could make injured lungs fit for a subsequent transplant. The idea: The organ would be removed from the donor, any damage repaired and the lung then used the receiver. Researchers have now taken a first step in the direction of this vision: they have not only developed a chamber in which extracted lungs can be kept fully functional at body temperature. They were also able to measurably improve the function of the organs by giving them gene therapy. In this way, the availability of high-quality donor lungs could almost be doubled, the researchers believe. Currently, more than 80 percent of eligible organs must be discarded because they are too severely damaged by intensive medical interventions or a violent inflammatory response. First, the scientists were looking for a way to administer the planned gene therapy outside the body. The conventional storage method is not suitable for this: In this case, removed organs are cut off from the blood supply and stored on ice? a method that almost brings the metabolism to a standstill and thus prevents that inserted genes are activated. The researchers finally opted for a small glass chamber. It was 37 degrees, and the lungs were flooded with a kind of fake blood to mimic the circulation and breathing. Both pig and human lungs, which could not be used for transplantation due to severe tissue damage, could be preserved without damage, an analysis showed.
In the second step, the scientists administered to the organs via the bronchi a genetically modified cold virus, which was also equipped with a control gene of the immune system. This gene, called IL-10, suppresses inflammatory reactions and overall calms the immune system. The strategy proved to be very successful: The treated pork loins swelled much less than the untreated ones, their blood flow after transplantation was measurably better and also the gas exchange was less impaired. The condition and function of the human lungs in the chamber also improved significantly.
Since inflammatory reactions, for example as a result of artificial respiration, are the most common cause of the poor condition of donor lungs, the researchers consider their approach very promising. This not only increases the number of organs suitable for transplantation, but also improves the overall quality of donor lungs, they write. However, it must first be demonstrated that the treated organs actually work better in the human body.
Marcelo Cypel (University of Toronto) et al .: Science Translational Medicine, Vol. 1, Article 4ra9 ddp / science.de? Ilka Lehnen-Beyel advertisement