Scientists grow mini-kidneys in a dish
Adult skin cells have been reprogrammed to make the most mature human kidneys yet to be grown in a laboratory, say researchers.
Although the kidneys cannot perform the functions of a fully formed adult kidney, it is hoped the breakthrough will someday lead to a new way to treat people suffering from kidney failure.
The research was highlighted in the journal Nature, which details how the mini kidneys developed just as normal kidneys do in an embryo.
"Ultimately we hope we might be able to scale this up so we can ... maybe bioengineer an entire organ," said lead researcher Professor Melissa Little, of the Murdoch Childrens Research Institute.
"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.”
The researchers reprogrammed adult fibroblasts to become 'induced pluripotent stem cells', which act like embryonic stem cells, and can become any cell in the body.
They did this by using a precise combination of chemicals, called growth factors, to guide embryonic stem cells to develop into the different cell types.
Read More: Brain game demonstrates telepathic link based on nerve impulses
By "tweaking" their growth factor recipe, the researchers were able to grow these cells into larger and more complex kidneys.
"These kidneys have something like 10 or 12 different cell types in them ... all from the one starting stem cell," said Professor Little.
"It's starting to mature now and the cell types are starting to do more of the functions of the final kidney."
While still early days, the method could provide a practical way to study inherited forms of kidney disease, the researchers said.
Read More: Scientists claim breakthrough in quest for invisibility technology
"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," said Professor Little.
It may also one day lead to rejection-free transplants for patients, she added.
“We a long way to 'transplantable kidneys' – these little guys can not be 'plumbed' into a waste drain, and it lacks large-scale features that are crucial for kidney function, such as a urine-concentrating medulla region."
"There is a long way to go until clinically useful transplantable kidneys can be engineered, but [this] protocol is a valuable step in the right direction."