Human hematopoietic stem cell vulnerability to ferroptosis

Hematopoietic stem cells (HSCs) have a number of unique physiologic adaptations that enable lifelong maintenance of blood cell production, including a highly regulated rate of protein synthesis. Yet, the precise vulnerabilities that arise from such adaptations have not been fully characterized. Here, inspired by a bone marrow failure disorder due to the loss of the histone deubiquitinase MYSM1, characterized by selectively disadvantaged HSCs, we show how reduced protein synthesis in HSCs results in increased ferroptosis. HSC maintenance can be fully rescued by blocking ferroptosis, despite no alteration in protein synthesis rates. Importantly, this selective vulnerability to ferroptosis not only underlies HSC loss in MYSM1 deficiency but also characterizes a broader liability of human HSCs. Increasing protein synthesis rates via MYSM1 overexpression makes HSCs less susceptible to ferroptosis, more broadly illustrating the selective vulnerabilities that arise in somatic stem cell populations as a result of physiologic adaptations. [Display omitted] •MYSM1 deficiency causes human HSC loss by ferroptosis•MYSM1-deficient HSCs have reduced translation of ferroptosis-protective mRNAs•Human HSCs, but not progenitors, are vulnerable to ferroptosis•Human HSC vulnerability to ferroptosis arises due to low rates of protein synthesis Hematopoietic stem cells have a low rate of protein synthesis that makes them selectively vulnerable to ferroptosis.