A reserve army in deep sleep: the blood stem cells that wait a lifetime

Most of your blood stem cells work shifts across your whole life. A few, it turns out, barely wake up at all — and that may be the point. Researchers at the German Cancer Research Center (DKFZ) and the HI-STEM institute, led by Andreas Trumpp with first author Dawn S. Lin, found a hidden population of blood stem cells in mice, marked by a surface protein called EPCR, that stay in deep sleep far longer than ordinary stem cells: after more than 200 days, 10 to 15% of them still carried a 'quiescence marker', against about 2% of conventional stem cells. Transplanted into mice, even single cells from this reserve rebuilt every type of blood cell — and kept doing so for life, even after being transplanted a second time. The study, in Cell Stem Cell, has not yet shown the same reserve exists in people; if it does, it could explain how blood renews itself into old age.

SDG 3 · Good health and well-being — Mechanism: tech innovation