Australian scientists create human kidneys from skin cells

A tiny human kidney has been grown in a dish by Australian scientists using stem cells, a lead researcher said on Thursday.

The scientists - from Melbourne's Murdoch Children's Research Institute - have reprogrammed stem cells and turned them into the most developed human kidney ever created in a laboratory.

The breakthrough is being seen as a crucial first step towards building new organs for patients in the lab.

Lead researcher Professor Melissa Little said the kidneys were still small, less than a centimeter across, but have hundreds of filtering units and blood vessels.

Little said the work had multiple practical implications, allowing scientists to one day test for the renal toxicity of drugs and, on a more individual level, to test for a person's predisposition to kidney diseases.

"The short-term goal is to actually use this method to make little replicas of the developing kidney and use that to test whether drugs are toxic to the kidney," she said, quoted by the Australian Broadcast Corporation.

"You can take a fibroblast (from someone with inherited kidney disease), make a stem cell out of it, generate a little kidney and use that as our model for their disease."

The engineered kidneys also appear to be developing in the same way as normal kidneys grow in a human embryo.

"Ultimately we hope we might be able to scale this up so we can. .. maybe bioengineer an entire organ," Little said.

The study was published in scientific journal Nature, and detailed how Little and her colleagues turned an ordinary fibroblast skin cell into a functioning kidney.

These fibroblast cells were first reengineered into "induced pluripotent stem cells," which have similar properties to embryonic stem cells, and then chemically adjusted into kidney cells.

Little said the team slightly adjusted their growth formula to produce their most complex and largest kidneys yet.

"These kidneys have something like 10 or 12 different cell types in them ... all from the one starting stem cell," said Professor Little.

"What we had previously were little flat structures over the surface of a dish... Now we have an organoid that is about 5-6 millimeters across."

"It's starting to mature and the cell types are starting to do more of the functions of the final kidney." Endi