Figure 2

DBA patients with mutations in RPS19 gene exhibited a normal erythroid differentiation phenotype compared with patients with mutation in RPL11, who exhibited a delay in erythroid differentiation. (a) May–Grünwald–Giemsa staining of the erythroid cells at D10 of terminal erythroid differentiation (orthochromatic erythroblasts) from controls, DBA patients with mutations in RPS19 gene or in RPL11 gene. The erythroblasts from the DBA patients with mutations in RPS19 (n=12) exhibited a normal terminal erythroid differentiation while the ones from the patients, who carry a mutation in RPL11 (n=3) exhibited a defect of terminal erythroid differentiation with a large number of necrotic cells. (b) Left panel: percentage of erythroid precursors (50 000 cells) labeled with the GPA/CD36 antibodies at D7, D10 and D12 of the terminal erythroid differentiation in DBA patients, one mutated in RPS19, one mutated in RPL11. Right panel: percentage of GPA/CD36⁺, CD34⁺ at D10 in the DBA patients carrying either a mutation in RPS19 (n=2) or RPL11 (n=3) gene compared with controls (n=8). Cells from patients who carried a mutation in RPS19 exhibited the same number of GPA/CD36⁺ or CD34⁺ cells as the controls. By contrast, erythroid precursors from patients, who carry a mutation in RPL11 gene, exhibited a decrease in GPA/CD36⁺ cells and a large increase in CD34⁺ cells, suggesting a delay in erythroid differentiation