EPO and anemia (phenotype): In line with this observation, several parameters reflected an accelerated turnover of RBC in anaemia: the number of young, CD71+ RBC (Fig. 5c) was increased, along with increased numbers of “old”/damaged, phosphatidylserine (PS+)-positive RBC (Fig. 5d), the latter being consistent with slightly increased levels of erythropoietin (Fig. 5e).