Figure 4: Modulation of mitochondrial metabolism alters HSC fate through autophagy.

(a) LT-HSC:TMRM^low (LKS CD150+ CD34− TMRM^low) cultured for 5 days under differentiation conditions in the presence or absence of FCCP were transplanted in lethally irradiated recipient mice together with 2*10⁶ helper cells. (b) Cells cultured in the presence of FCCP show high levels of multi-lineage reconstitution, in contrast to controls lacking FCCP that result in rapid differentiation (error bar: s.e.m.; t-student, **P<0.01 and *P<0.05). (c) Mitochondrial mass (TOMM20, cyan) and autophagosomes (LC3B, red) in different haematopoietic stem/progenitor cell populations. Images represent maximum intensity projections of the corresponding Z-stacks (0.28 μm step) Scale bar: 5 μm. (d–f) Quantification of the mito-EGFP (d), LC3B (e) and mito-EGFP/LC3B ratio intensity-thresholded areas (f). (g) Gene expression analysis on key autophagosomal and mitophagic genes was performed on LT-HSCs treated over 5 days with FCCP (error bar: s.e.m.; t-student, ***P<0.001, **P<0.01 and *P<0.05).