Impact of environment on Red Blood Cell ability to withstand mechanical stress

Abstract

Susceptibility of red blood cells (RBC) to hemolysis under mechanical stress is represented by RBC mechanical fragility (MF), with different types or intensities of stress potentially emphasizing different perturbations of RBC membranes. RBC membrane mechanics were shown to depend on cell environment, with many details not yet understood. Here, stress was applied to RBC using a bead mill with oscillation up to 50 Hz, over durations up to 50 minutes. MF profiles plot percent lysis upon stresses of progressive durations. Supplementing media with polyethylene glycol (PEG) which interacts with the cell membrane, but not Dextran which does not, resulted in higher resistance to hemolysis. Albumin, and to a lesser extent fibrinogen and globulins (at physiological concentrations), significantly increased cell ability to withstand mechanical stress versus with un-supplemented buffer solution and with PEG. This is partly due to changes in rheology, per tests done including (PEG) and Dextran, but is mostly due to cell-protein interaction, noting the effect of pH on RBC MF with albumin but not with buffer. Presence of lipids reduced RBC resistance to potentially hemolytic stress with lypemic plasma effecting lower "protection" from induced hemolysis than essentially fatty-acid free plasma. This effect was less dependent on incubation than on fatty-acid presence during stressing. The reduced propensity for hemolysis afforded by plasma proteins also depended markedly on the speed of the bead, potentially reflecting changes from a predominantly Von Karman trail at lower frequencies to an increasingly disorganized turbulent wake at higher frequencies.

Dextran- Versus Crystalloid-Based Prime in Cardiac Surgery: A Prospective Randomized Pilot Study

“…The mechanism behind the lower hemolysis with dextran is not fully understood, but it has been suggested that dextran reduces the effects of shear stress on red blood cells (19,20).…”

The role of the erythrocyte in the outcome of pregnancy with preeclampsia

“…The mechanical stability of erythrocytes also deserves attention [26–28], especially for the analysis of erythrocyte membrane behavior in situations of increased mechanical aggression, which is the main challenge found by red cells in the blood circulation of women with preeclampsia.…”

Impact of the Oscillating Bead Size and Shape on Induced Mechanical Stress on Red Blood Cells and Associated Hemolysis in Bead Milling

“…Prospect, IL). Mechanical Fragility (MF) testing and profile development was performed using a vertically oscillating bead in a sample and having incremental hemolysis being measured at respective stressing durations, as was described previously [7], except now using custom made cylindrical beads in addition to the standard spherical (ball) beads. Area Under the Curve (AUC), representing the area under the collected fragility profile, is a profile-based value that was used here to evaluate induced hemolysis over a given aggregate stress duration.…”

“…protective effect afforded by albumin can be attributed to changes in properties of turbulent flows in the bead's wake [7]. Furthermore, use of a cylindrical (rather than spherical) bead introduces additional stresses, beyond those of the bead's turbulent wake, associated with the bead's annulus (which is notably minimal in the case of a spherical bead).…”

“…It had been demonstrated previously that for a sphere/ ball, hemolysis is caused predominantly by wake turbulence, with presumably ball speed (related to oscillation frequency) and viscosity affecting the nature of turbulence in the medium [7]. Then, an additional ability to vary the type(s) of hemolysis-inducing stress was introduced, regarding when the spherical bead is replaced with a cylindrical bead design [8].…”