Kidney transplantation remains the most effective treatment for end-stage kidney disease, yet a severe shortage of donor organs continues to limit access for millions of patients worldwide. With demand for kidney transplants expected to reach 5 million patients by 2030 and only a fraction of that need currently being met, researchers are exploring innovative approaches to generate transplantable organs.
In a study published today in Stem Cell Reports , Shunsuke Yuri of the National Center for Geriatrics and Gerontology, Japan and Ayako Isotani of the Nara Institute of Science and Technology, Japan, successfully generated rat-derived kidneys in mice using a technique known as interspecies blastocyst complementation. The researchers created mouse embryos genetically unable to form kidneys, leaving a developmental niche that could be filled by injected embryonic stem cells. When rat embryonic stem cells were introduced into these embryos, they contributed extensively to kidney formation, particularly to nephron progenitor cells and ureteric bud lineages, resulting in the generation of a rat cell-derived kidney.
Although the interspecies embryos did not survive to birth, preventing assessment of kidney function, the study demonstrates the potential of using one species to generate organs from another. The findings represent an important step toward future efforts to grow transplantable human organs in larger animals, such as pigs, with the long-term goal of helping address the global shortage of donor kidneys.
About Stem Cell Reports
Stem Cell Reports is the open access, peer-reviewed journal of the International Society for Stem Cell Research (ISSCR) for communicating basic discoveries in stem cell research, in addition to translational and clinical studies. Stem Cell Reports focuses on original research with conceptual or practical advances that are of broad interest to stem cell biologists and clinicians. Stem Cell Reports is a Cell Press partner journal. Find the journal on X: @StemCellReports .
About ISSCR
Across more than 80 countries, the International Society for Stem Cell Research ( @ISSCR ) is the preeminent global, cross-disciplinary, science-based organization dedicated to advancing stem cell research and its translation to medicine.
Stem Cell Reports
Rat cell–derived kidney generation via interspecies blastocyst 2 complementation in an Osr1-KO mouse model
11-Jun-2026