Membrane skeleton and red blood cell vesiculation at low pH.

Shapes of red blood cells at low pH were studied theoretically. It is assumed that the equilibrium shape of the red blood cell corresponds to the minimum of its membrane elastic energy which consists of the bending energy and relative stretching energy of the bilayer, the stretching energy of the skeleton and the interaction energy between the skeleton and the bilayer. It is shown that the aggregation of the skeleton at low pH can cause the red blood cell shape transformation from the stomatocytic shape to the cell shape composed of a spherical parent cell having the bilayer completely underlaid with the skeleton and spherical daughter vesicles without the skeleton.