Lab-Made Kidneys Capable Of Producing Urine Successfully Transplanted Into Live Rats

In yet another leap forward in the world of bioengineered organs, researchers have successfully transplanted a lab-made kidney capable of producing urine into a live rat. The procedure, developed by scientists at the Massachusetts General Hospital (MGH), involves stripping down an organ to its cellular architecture, then repopulating it with new cells. 

"What is unique about this approach is that the native organ's architecture is preserved, so that the resulting graft can be transplanted just like a donor kidney and connected to the recipient's vascular and urinary systems," says senior author Harald Ott from the MGH Center for Regenerative Medicine. 

"If this technology can be scaled to human-sized grafts, patients suffering from renal 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 achieve the functioning kidney, scientists decellularized a rat kidney, then confirmed that the remaining collagen blueprint preserved the organ's structural integrity. The barebones kidney was then populated with human endothelial cells and newborn rat kidney cells. After a 12-day gestation period, the kidney was then tested for its filtration abilities. In both lab tests, and in live rats, the kidneys almost immediately started producing urine once a proper blood flow was established, indicating that it worked.

In the United States alone, over 18,000 kidney transplants are performed each year, with hundreds of thousands of patients still  left on the waiting list. The scientists hope that if this procedure takes off, kidneys can be made on demand, using the patient's own cells to populate the kidney structure, removing many of the inherent risks normally associated with transplants such as rejection. To demonstrate the potential, scientists even decellularized pig and human kidneys. 

"Further refinement of the cell types used for seeding and additional maturation in culture may allow us to achieve a more functional organ," says Ott. "We're now investigating methods of deriving the necessary cell types from patient-derived cells and refining the cell-seeding and organ culture methods to handle human-sized organs."

You can read the full published study in Nature Medicine.