Around 2% of all adults experience kidney disease, and which results in tens of thousands of deaths each year. Only 25% of those on the wait list for a donor kidney will ever receive the lifesaving call. Researchers have announced that they have grown a rudimentary kidney in the laboratory using human stem cells, which may give more treatment options to those with renal disease. The paper was published in Nature Cell Biology by Melissa Little from the University of Queensland's Institute for Molecular Bioscience.

The kidney is an organ in the urinary system which is used to ensure homeostasis in the body by regulating electrolytes, pH of the body, and even blood pressure. It is built from two different stem cell types. The team working in Little’s lab originally meant to create one kind, but was very surprised to discover that both cells had been created. As the cells began to grow and proliferate, they assembled themselves into a miniature human kidney. The team used specific growth factors along with information about normal embryological development in order to guide the cells toward the intended complete organ.

Earlier this year, an American team announced that they had created a rat kidney from stem cells, though it was incredibly inefficient when transplanted into an organism. This organ from Little’s lab was created with human stem cells and can give researchers an unprecedented insight into how new medications will impact human kidneys, which can dramatically improve success in clinical safety trials. They also represent the potential for improved treatment of renal disease, as that is an area that is lacking at present. For those who are suffering renal disease, dialysis and organ transplantation are the two main treatments available. Eventually, decades down the road, this technology could potentially be used to create full-sized replacement organs for those who have exhausted all other options.

Currently, the kidneys are very small and are about the size that you would find in a five-week old human embryo. This technology needs to become much more advanced before it will be useful in a clinical setting, but that does not at all take from the significance of this announcement. The cellular complexity of this newly manufactured kidney is unlike anything that has been seen before in lab-grown organs. Using stem cells to create new organs for drug safety testing and transplantation purposes has been a goal among those in regenerative medicine for years, and the results from Melissa Little’s lab presents a very large step forward.