Kidney disease is extremely prevalent: it is estimated that 100,000 patients are awaiting kidney transplants in the U.S. alone, while an additional 400,000 require extensive dialysis. If engineering entire kidneys were made possible, it could solve the problem of organ shortage that exists throughout the world.
A group from Massachusetts General Hospital and Harvard Medical School made a critical step towards this goal. They have bioengineered an entire kidney and transplanted it into a lab rat. Most importantly, this artificially-generated kidney was able to produce urine and showed renal function in the rat that received the transplant.
One of the major problems in making a bioengineered organ is that it must have the correct architecture. In order to provide this, the first step in the new method was to take healthy kidneys from rats and remove all the cells while keeping the extracellular matrix, thus providing a scaffold in which new cells can grow. These scaffolds were then seeded with cells and transferred to a whole organ bioreactor where they received proper nutrients. These rudimentary kidneys were then transplanted and were able to recapitulate basic kidney function such as producing urine.
This method, if scaled up and successful in humans has an added advantage in regards to organ rejection. Since the scaffold can be coated with the recipient’s own cells, there will be no organ rejection due to incompatibility of immune systems. This is especially relevant for kidney donations since up to 40% of recipients die within 10 years due to rejection.
Study in Nature Medicine: Regeneration and experimental orthotopic transplantation of a bioengineered kidney…