Receptor expression in erythroblasts in relation to their maturative stage, measured by GpA intensity.

The mean levels of Fas were significantly higher in all erythroblast subsets (P < .05) from MM patients with severe anemia (A) compared to those from patients of the control group (B). Both DR4 and DR5, as agonist receptors for TRAIL, were also up-regulated in erythroblasts from anemic patients though prevalently in the GpA^+interm subset. By contrast, Fas-L and TRAIL occurred at comparable values in both groups and exhibited their maximal intensity in GpA^+bright cells. The analysis was completed by flow cytometry using the Cell-Quest software and values are expressed as mean ± SEM.