Red blood cells (RBC) change upon hypothermic conservation, and storage for 6 weeks is associated with the short-term clearance of 15-20% of transfused RBC. Metabolic rejuvenation applied to RBC before transfusion replenishes energetic sources and reverses most storage-related alterations, but how it impacts RBC circulatory functions has not been fully elucidated.

Six red cell concentrates (RCC) stored under blood bank conditions were analyzed weekly for six weeks, and rejuvenated on day 42 with an adenine-inosine-rich solution.

Impact of storage and rejuvenation on ATP levels, morphology, accumulation of storageinduced micro-erythrocytes (SME), elongation under an osmotic gradient (by LORRCA), hemolysis and phosphatidylserine exposure (PS) was evaluated. The impact of rejuvenation on filterability and adhesive properties of stored RBC was also assessed.

the PS exposure from 2.78% to 0.41%. Upon rejuvenation, the proportion of SME dropped from 28.2% to 9.5%, while the proportion of normal-shaped RBC (discocytes and echinocytes I) increased from 47.7% to 67.1%. In LORCCA experiments, rejuvenation did not modify the capacity of RBC to elongate and induced a reduction in cell volume. In functional tests, rejuvenation increased RBC filterability in a biomimetic splenic filter (+16%) and prevented their adhesion to endothelial cells (-87%).

Rejuvenation reduces the proportion of morphologically-altered and adhesive RBC that accumulate during storage. Along with the improvement in their filterability, these data show that rejuvenation improves RBC properties related to their capacity to persist in circulation after transfusion.