Stomatocyte–discocyte–echinocyte sequence of the human red blood cell: Evidence for the bilayer– couple hypothesis from membrane mechanics

TLDR

Red‑cell shape is determined by the mechanical properties of the membrane, with bending rigidity from the plasma membrane and stretch/shear elasticity from the protein skeleton. By incorporating both bending and shear elasticity, the membrane mechanics model reproduces the stomatocyte–discocyte–echinocyte sequence through variation of a single bilayer‑couple parameter. The model accurately reproduces the full stomatocyte–discocyte–echinocyte sequence. The bilayer‑couple hypothesis originates from Sheetz and Singer (1974), Proc.

Abstract

Red-cell shape is encoded in the mechanical properties of the membrane. The plasma membrane contributes bending rigidity; the protein-based membrane skeleton contributes stretch and shear elasticity. When both effects are included, membrane mechanics can reproduce in detail the full stomatocyte–discocyte–echinocyte sequence by variation of a single parameter related to the bilayer couple originally introduced by Sheetz and Singer [Sheetz, M. P. & Singer, S. J. (1974) Proc. Studies, M. P. & Singer, S. J. (1974) Proc. Natl. Acad. Sci. USA 71, 4457–4461].