A ten year old Swedish girl has become the world’s first patient to receive a vein which was donated by a cadaver and treated with stem cells.
The girl required the transplant after suffering from chronic blockages of her hepatic portal vein. The hepatic portal vein is a large vein (roughly 8cm long in adults) in the body which carries out the role of transporting blood from the gastrointestinal system (spleen, gut) into the inferior surface of the liver. The vein is called a ‘portal vein’ as it cannot truly be considered a vein. This is because it carries blood to the liver, not the heart.
In order to be transplanted, the 9cm section of vein, removed from the groin of the cadaver, was chemically ‘stripped’ of the cadaver’s DNA. The next step was to take endothelial and smooth muscle cells from the recipient’s bone marrow and culturing these cells in the lab. The surface of the vein was then coated in the cultured cells and transplanted into the recipient. As the vein contained no trace of the donor’s DNA and was already coated in the recipient’s DNA, there was no need for the girl to take immunosuppressive drugs.
Immunosuppressive drugs are given to patients receiving donated organs which have not been treated with stem cells in order to prevent the body’s immune system from attacking the donated organ. This process is known as rejection. There are three main types of immunosuppressive drugs currently being used for transplant patients:
cyclosporins – these prevent or inhibit the production of T-lymphocyte cells, thus preventing the organ from being ‘attacked.’
azathioprines – these disrupt and prevent the synthesis of RNA and DNA, thus disrupting cell division.
corticosteriods – these suppress the inflammation caused by the immune response which occurs when an organ is being rejected.
Many transplant patients are required to take drugs like those previously mentioned for the rest of their lives. This can lead to other health complications, so there is hope that the new process of stripping donated organs of the donor’s DNA and recoating with stem cells with reduce the use of immunosuppressive drugs in transplant patients. This method has been previously used in 2009, when a woman received a windpipe transplant using the same method. In the future, doctors and research hope to increase the potential of this transplant method by the use of animal organs or synthetically created organs.
by Laura Cherry