The first step in the procedure involved taking a donor rat kidney and using a detergent to wash away its functional cells. What remained was the extracellular matrix scaffold, a protein structure that preserved the kidney’s underlying three-dimensional architecture. They then placed kidney and blood vessel cells taken from newborn rats onto the scaffold, using pressure generated from a vacuum to move the cells to the right areas. The “seeded” organ was then placed in a bioreactor to allow the cells to grow up and form a healthy, functional kidney.
The study was published in the April 14 issue of Nature Medicine.
Although it might not work as well as a cadaver kidney, the fact that it generated urine in a breathing, eating rat is a major proof-of-principle. Harald Ott, the study’s senior author, plans to optimize the cell-seeding procedures to improve performance. And as he states in the video below, they’re not just thinking about kidneys: “The reason I’m most excited about this recent publication is because it shows the platform character of this technology. The technology can be applied to any tissue, any organ that can be perfused by its own vascular system.”
Almost a million people in the United States are living with end-stage kidney disease. Another 100,000 are diagnosed every year. As yet there is no way to restore a failed kidney to good health. Hemodialysis is the most common treatment, but while dialysis prolongs a person’s life, it burdens the patient with time lost, limits on how much fluid they can drink, and often low energy. The only curative treatment is receiving a new kidney. Approximately 100,000 people in the US are waiting for a new kidney, but each year only 18,000 kidney transplants are performed here. Average wait time for a new kidney is three to five years. During that time, 10 to 15 percent of patients die.
The day this technology impacts humans is still a long way off. When it does, however, it will bring those in need to the front of very long waiting lists.