Impact of glycocalyx structure on red cell–red cell affinity in polymer suspensions

A theoretical framework based on macromolecular depletion has been utilized in order to examine the energetics of red blood cell interactions. Three different glycocalyx structures are considered and cell–cell affinities are calculated by superposition of depletion, steric and electrostatic interactions. The theoretical model predicts a non-monotonic dependence of the interaction energies on polymer size. Further, our results indicate that the glycocalyx segment distribution has a large impact on adhesion energies between cells: a linear segment distribution induces the strongest adhesion between cells followed by pseudo-tail and uniform distributions. Our approach confirms the concept of a depletion mechanism for RBC aggregation, and also provides new insights that may eventually help to understand and quantify cellular factors that control red blood cell interactions in health and disease.