Pyrimidoindole derivatives are agonists of human hematopoietic stem cell self-renewal

Human adult stem cell expansion Transfused blood saves lives. Despite the widespread use of this critical resource, it is difficult to increase blood cell numbers outside of the body. By screening thousands of small compounds, Fares et al. identify a molecule that expands human stem cell numbers in cord blood. The researchers generate many variations of that molecule and show that one such compound provides even greater human blood cell expansion. If researchers can provide increased numbers of stem cells and progenitor cells, cord blood should find even greater use in the clinic. Science , this issue p. 1509