A team at the University of Edinburgh used stem cells to create kidney organoids that perform genuine filtration — a landmark step toward lab-grown organs for transplant patients.
Roughly 800 million people worldwide suffer from kidney disease, and the global shortage of donor kidneys means that tens of thousands of patients die each year waiting for a transplant. A new study offers a glimpse of a future where that shortage is solved — not by finding more donors, but by growing replacement kidneys from a patient's own cells. Researchers at Edinburgh have created kidney organoids — tiny, lab-grown kidney structures — that can filter blood-like fluid and excrete waste products in a way that genuine kidney tissue does.
The team is clear that a transplantable kidney remains years away. Current organoids are roughly 3 millimetres in diameter — a functional kidney is about the size of a fist. Scaling up requires solving the vascularisation problem: how to grow a network of blood vessels dense enough to supply oxygen to every cell throughout the organ. Several groups worldwide are working on bioprinted vascular scaffolds as one potential solution. The Edinburgh team's contribution is demonstrating that the functional core — the filtration units — can self-organise correctly from stem cells.
"For the first time, we have a kidney organoid that doesn't just look like a kidney — it actually does something a kidney does."
— Lead author, University of Edinburgh, 2026