Maintenance of Stemness in ex vivo Expanded HSCs

Current ex vivo expansion methods usually compromise hematopoietic stem cells (HSCs) due to induced senescence after hyperproliferation in a microenvironment unlike the in vivo niche. Now, researchers led by Lingbo Liu (Huazhong University of Science and Technology, Wuhan, China) reveal the activation of both p38α and mammalian target of rapamycin complex 1 in ex vivo expanded human umbilical cord blood (hUCB)-derived HSCs. Li et al. report that the co-inhibition of these two pathways supports HSC stemness by inhibiting senescence through the downregulation of the spliceosome, proteasome, and pyrimidine metabolism signaling pathways. For more, see STEM CELLS Translational Medicine now!