February 1 2022
Lab: Kenichi Miharada
CD244 expression represents functional decline of murine hematopoietic stem cells after in vitro culture
Shusei Koide, Valgardur Sigurdsson, Visnja Radulovic, Kiyoka Saito, Zhiqian Zheng, Stefan Lang, Shamit Soneji,
Atsushi Iwama and Kenichi Miharada
iScience January 21, 2022
Isolation of long-term hematopoietic stem cell (HSC) is possible by utilizing flow cytometry with multiple cell surface markers. However, those cell surface phenotypes do not represent functional HSCs after in vitro culture. Here we show that cultured HSCs express mast cell-related genes including Cd244. After in vitro culture, phenotypic HSCs were divided into CD244- and CD244+ subpopulations, and only CD244- cells that have low mast cell gene expression and maintain HSC-related genes sustain reconstitution potential. The result was same when HSCs were cultured in an efficient expansion medium containing polyvinyl alcohol. Chemically induced endoplasmic reticulum (ER) stress signal increased the CD244+ subpopulation, whereas ER stress suppression using a molecular chaperone, TUDCA, decreased CD244+ population, which was correlated to improved reconstitution output. These data suggest CD244 is a potent marker to exclude non-functional HSCs after in vitro culture thereby useful to elucidate mechanism of functional decline of HSCs during ex vivo treatment.