Finally, erythroid progenitors (P < 0.05; Fig. 1d) and HSPCs (P < 0.01, Fig. 1e) from MDS patients also demonstrated significantly increased surface expression of PD-L1 versus expression in normal progenitors, indicating an autonomous regulation of immune checkpoint signaling in these MDS hematopoietic populations. This evidence concerns the gene CD274 and myelodysplastic syndrome.