NatureHaematopoietic stem cell number is not solely defined by niche availabilityShoichiro TakeishiTony MarchandWade R. KobaDaniel K. BorgerChunliang XuChandan GuhaAviv BergmanPaul S. FrenetteKira GritsmanUlrich Steidl2025-08-27Full textDOI https://doi.org/10.1038/s41586-025-09462-5