Two research teams in the last two months have published studies on kidney structures grown from stem cells, which might be a step toward personalized replacement organs grown from patients’ own cells.
“We have converted skin cells to stem cells and developed a highly efficient process to convert these stem cells into kidney structures that resemble those found in a normal human kidney,” biologist Ryuji Morizane of Brigham and Women’s Hospital, lead author of a new study in the journal Nature Biotechnology, said in a statement.
Earlier this year, a team of Australian medical researchers lead by Minoru Takasato also succeeded in growing nephron organoids from stem cells in the lab. They published their results in the journal Nature.
Certain chemical signals can trigger stem cells to develop into specialized cells, or differentiate. In recent years, scientists have discovered ways to induce stem cells to differentiate into heart, liver, nerve, and pancreas cells. To grow kidney structures, Morizane and his team used genetic techniques to develop skin cells into stem cells, which they then developed into what are called “precursor cells,” a type of stem cell that’s only partially differentiated. These precursor cells developed into kidney cells and assembled themselves into structures that looked much like those found in real, live kidneys.
The results of their work are organoids, three dimensional organ structures grown in a lab, which are very similar to kidney structures called nephrons. Morizane and his colleagues published their work in the journal Nature Biotechnology.
Nephrons are the basic working structures in you kidneys; they filter excess water, salts, and harmful substances out of your blood and turn them into urine. Each kidney has about a million nephrons, which sounds like a lot — but it’s a finite supply. Once you lose nephrons to disease or injury, your body can’t replace them.
Donor kidneys are in short supply, however, and transplants come with some risk. Morizane and his colleagues hope that their research will be a step toward one day growing replacement kidneys from patients’ own cells - and idea that has long been a popular theme in discussions about stem cell research. They’ve grown nephron-like structures, not whole kidneys, but Morizane says it’s a step in the right direction.
