MPO and myelodysplastic syndrome: Immunofluorescence for LC3B (Microtubule-Associated Protein Light Chain 3B) showed enhanced autophagosome formation, namely increased punctuated signals in MDS MPO+ cells, that is in the differentiating myeloid lineage (Figure 3A,B), while the phenomenon was virtually absent from CD34+ HSCs (Supplementary Figure S2).