Hematopoietic Stem Cell Heterogeneity: Subtypes, Not Unpredictable Behavior

Thanks to well-established quantitative functional assays and prospective isolation methods, hematopoietic stem cells (HSCs) are among the best understood stem cells. Nevertheless, recent studies have identified new HSC subtypes with distinct properties within previously characterized populations, leading us to question long-held views on the underlying basis of HSC heterogeneity.