Researchers said that they had bio-engineered a kidney and transplanted it into rats, marking a step forward in a quest to help patients suffering from kidney failure. The goal was to help the millions of people with kidney failure whose lives are crimped by dialysis. This prototype proves that a "bio-kidney" can work, emulating breakthroughs elsewhere to build replacement structures for livers, hearts and lungs. As described in the journal Nature Medicine, the work entailed taking a rat kidney and stripping out its living cells using a detergent solution, leaving behind a shell made of collagen.
The next step was to repopulate this empty structure with living cells, comprising human endothelial cells, which line the walls of blood vessels in the kidney, and kidney cells taken from newborn rats. The trick was then to "seed" these cells in the correct part of the kidney, using a muscle duct called the ureter as a tube.
The organ was transplanted into living rats from which a kidney had been removed. The new kidney started filtering blood and producing urine through the ureter as soon as the blood supply was restored, and there was no evidence of bleeding or clots.
The researchers stripped cells from pig and human kidneys to test the first phase of the procedure on these organs, but have not taken this further for now. If this technology can be scaled to human-sized grafts, patients suffering from kidney failure who are currently waiting for donor kidneys or who are not transplant candidates could theoretically receive new organs derived from their own cells to prevent rejection by the immune system.