Is TGF-β a stemness regulator?

In this issue of Blood, Yamazaki and colleagues show that TGF-beta inhibits cytokine-mediated LRC clustering in purified HSCs freshly isolated from the bone marrow and induces hibernation of HSCs ex vivo. Since cytokine stimulation of LRC is important to stimulate proliferation of HSCs, the authors propose that TGF-beta may be a hibernation/quiescence regulator in the HSC bone marrow niche.