Research into an alternative way to store kidneys

Organ transplantation is a race against time

There are never enough donor organs. The organs that are available must be transplanted as quickly as possible. Medicine is therefore fully committed to keeping organs healthy for longer. Marlon de Haan is researching at the Leiden University Medical Center (LUMC) how you can keep kidneys alive outside the body.

Organ transplantation is a race against time. An organ must be transplanted within 24 hours. It must be removed from the donor, transported, checked and placed with the recipient. Marlon de Haan is researching how you can extend this period for kidneys. ‘An organ is, as it were, an organism, with individual cells that all have their own energy needs,’ he explains. ‘Until now, we have reduced the energy requirement of a donor organ by storing it on ice. Cooling slows down the metabolism.’

For his PhD, De Haan is researching an alternative way of storing kidneys. Instead of being cooled, the kidney is kept in a perfusion system. ‘That is a kind of pump that can supply the organ with nutrients. By adding oxygen, sugar and protein to the kidney, we try to keep the organ alive for longer – and ultimately have more time for a transplant. It has already been possible to extend the lifespan of a pig kidney in the lab, but also of a human kidney that was rejected for transplantation. That worked for up to four days. The first important step has therefore been taken.’

More time is not the only benefit. ‘If there is any doubt about the quality of a donor organ, it will not be used’, explains De Haan. ‘But in a perfusion system, the functioning of an organ can be monitored for a longer period of time. If the initial doubts have been removed and the organ appears to be functioning properly, it can still be transplanted. In addition, it is possible to condition an organ in the perfusion system. By making small adjustments, the organ can be made more suitable for a specific recipient. This reduces the risk of rejection.’

Pork kidney
Storage and conditioning are already very successful in some organs, such as the liver. For the kidney, however, it is still music in the future. ‘The kidney is one of the most complex organs in the body,’ explains De Haan. ‘That’s because a kidney consists of almost thirty types of cells. For comparison, a heart has about ten. Not only do all those cells have their specific energy needs, it is also important how they work together. We are trying to find out by experimenting with pig kidneys.’

Pig kidneys are often used for medical research because they are very similar in size, structure and appearance to human organs; also on a cellular level. De Haan and his colleagues will collect the kidneys from the slaughterhouse themselves. “The situation should resemble the reality of a transplant,” he says. ‘That is why the organs are quickly removed after slaughter and transported on ice. We’ll go straight to the lab and get to work.’

Internships
De Haan finds it difficult to say where his fascination for organs comes from. “I think a high school biology teacher inspired me. She made sure that I could spend a day at Erasmus MC in the heart department. Later I made my profile piece about the heart. My bachelor’s research was also about the heart, namely the idea of ​​making a contractile heart tube.’

De Haan will have obtained his PhD rather than graduated, because his internships came to a standstill due to corona. On the other hand, he had room to participate in this research project. “When you start this, you know you can’t stay to the end,” he says. ‘Only when the application can be used on patients will the research be successful. You can’t do that within a four-year PhD. I do hope to remain indirectly involved in this research in addition to my internships. And maybe I’ll return after graduation; it just depends on how well you like clinical medicine.’

Bron: LUMC / Wilke Martens