For the first time mouse pancreases have been developed in rats to cure mouse diabetes. When small parts of these organs were transplanted into mice with diabetes, it reversed their disease.
The research opens another avenue to replace or restore malfunctioning organs in humans. Current donor rates can’t keep pace with the thousands of patients lingering on wait lists, including those waiting for human pancreatic islets.
The success of the interspecies transplantation suggests that a similar technique could one day be used to generate matched, transplantable human organs in large animals like pigs or sheep.
The team of researchers from Stanford University and the University of Tokyo first genetically modified rats so their offspring wouldn’t develop a pancreas. Then, when these rats conceived, they injected pancreas-building mouse stem cells into the rat embryos, which yielded a rat with a mouse pancreas. Once the rats had grown and their organs were mature, the researchers removed critical cells, called islets, from their pancreases and implanted them into diabetic mice.
Once these mice received the pancreatic islet cells from hybrid rats, their bodies began naturally adjusting glucose levels. The mice survived over a year with their new cells and only required immunosuppressant drugs for five days, these drugs are typically lifelong companions for most organ transplant recipients.
This is the first time this kind of inter-species organ generation has successfully treated a medical condition. “It proved those pancreatic islets must be very functional,” said Hiromitsu Nakauchi, MD, PhD, a professor of genetics at Stanford.
Human implementation of this latest method is likely years away; the process needs refinements and there ethical considerations to account for before growing custom human organs in another animal.
The findings are published in the journal Nature.