Long-term storage of cRBCs. Purified cRBCs and native reticulocytes were stored at 4°C for up to 4 weeks in a Sag-Mannitol–based preservative solution. (A) Comparative kinetics of cell recovery during long-term storage of cRBCs and native reticulocytes (native Ret). Mean ± SEM of 9 and 6 experiments, respectively. (B) Evolution of the hemoglobin content during storage of cRBCs. Mean ± SEM and the number of experiments is indicated on each bar. (C-D) CD71 expression, reticulocyte content (C) and deformability (D) were evaluated before (fresh cRBCs) and after 4 weeks of storage (stored cRBC). Mean of 2 experiments. (E) Comparative kinetics of CD71⁺ cells among CFSE⁺ cells in mouse blood after injection of fresh (n = 4 mice) or stored (n = 2 mice) purified cRBC. Data for fresh cRBC are from Figure 4A, and the results are expressed as the mean ± SEM. Confocal microscopy image shows CFSE-labeled stored cells 3 days after injection into mice.