Effect of blood bank storage on the rheological properties of male and female donor red blood cells

It was previously demonstrated that red blood cell (RBC) deformability progressively decreases during storage along with other changes in RBC mechanical properties. Recently, we reported that the magnitude of changes in RBC mechanical fragility associated with blood bank storage in a variety of additive solutions was strongly dependent on the donor gender [15]. Yet, the potential dependence of changes in the deformability and relaxation time of stored blood bank RBCs on donor gender is not known. The objective of this study was to determine the effects of donor gender and blood bank storage on RBC deformability and relaxation time through the measurement of RBC suspension viscoelasticity. Packed RBC units preserved in AS-5 solution from 12 male and 12 female donors (three from each ABO group) were obtained from the local blood center and tested at 1, 4 and 7 weeks of storage at 1-6 degrees C. At each time point, samples were aseptically removed from RBC units and hematocrit was adjusted to 40% before assessment of cell suspension viscoelasticity. RBC suspensions from both genders demonstrated progressive increases (p < 0.05) in viscosity, elasticity and relaxation time at equivalent shear rates over seven weeks of storage indicating a decrease in RBC deformability. No statistically significant differences in RBC deformability or relaxation time were observed between male and female RBCs at any storage time. The decrease in RBC deformability during blood bank storage may reduce tissue perfusion and RBC lifespan in patients receiving blood bank RBCs.