University of Minnesota stem cell researchers, together with collaborators at Stanford University, have successfully used adult stem cells to replace the immune system and bone marrow of mice, offering the promise of new therapies for people in the future. With this advance and other recent discoveries, the researchers are winning over previous skeptics. For decades, researchers have tried in the lab to expand hematopoietic stem cells (cells that give rise to the blood system). Success in this venture would mean increasing the supply of cells available for bone marrow transplant patients. The researchers used multipotent adult progenitor cells (MAPCs), which...