The now disbanded NeuroSpheres laboratory team showed that in mice, neural stem cells (NSCs) could become hematopoietic cells in vivo. According to lead author Christopher R. R. Bjornson, now a biochemistry graduate student at the University of Washington, the NeuroSpheres researchers noted a few instances in which certain cells would express traits of other cell lineages.4 "From that we started to really question ... whether or not stem cells were only confined to a certain subset of fates," he explains.
To test this concept, he and his colleagues first irradiated mice to eliminate most of the animals' endogenous hematopoietic precursors. A key step, says Bjornson, was using a sub-lethal dose of radiation rather than lethal doses, which often are used for bone marrow (BM) transplants. They correctly reasoned that the NSCs would take longer than BM cells to become hematopoietic and they did not want the mice to degenerate too ...
