Forma, Vol. 8 (No. 2), pp. 233-243, 1993

Mechanics of Red Blood Cells. Structural and Mechanical Aspects of a Triple Layer Membrane Model

D. Lerche

Institute of Medical Physics and Biophysics, Charité, Humboldt-University, 10098 Berlin, Germany

(Received September 30, 1993; Accepted December 7, 1993)

Keywords: Erythrocyte, Membrane Structure, Membrane Mechanics, Deformability, Cell Shape

Abstract. Composition and structure of RBC membrane are reviewed. The mechanics of an RBC membrane is analysed in the frame work of a proposed triple layer membrane model (TLM). These 3 layers—glycocalyx, conventional lipid bilayer and skeleton—are differently involved in the mechanical membrane characteristics (compressibility, shear elasticity, bending elasticity modulus, respectively, and spontaneous curvature). Whole cell deformation may be caused by "internal" forces and "external" forces. Shape change depends primarily upon geometrical features and membrane properties. It is caused by cell metabolism and specific as well as unspecific chemical reactions. Cell deformation by external forces depends on the cell property rigidity and the applied force. Static and dynamic cell rigidity, respectively, has to be considered with regard to the time scale of the deformation process.