A model for rouleaux pattern formation of red blood cells.
Human red blood cells (RBCs) in a solution form rouleaux patterns under various conditions. The degree of rouleaux formation depends on, for example, the concentration and molecular weight of added large molecules. We present a two-dimensional discrete cellular space model in which an RBC is represented by a rectangle and differential adhesion is assumed among the longer (a-site), the shorter (b-site) sides of the rectangle and the solvent. The total sum of the adhesion energy is assumed to guide the step-by-step change of the model cell configuration and also define absolutely stable patterns. We compare the set of absolutely stable patterns and cell aggregate patterns for both actual and computer-simulated cases to obtain the basic validity of our framework. Then we proceed to assess the effects of added high polymers to the adhesion parameters. We first note that under suitable conditions, decrease in a-site-solvent affinity is necessary to have complex patterns rather than increase of a-a affinity. The hypothesis that addition of high polymers reduce the a-site-solvent affinity is concomitant with a newly proposed osmotic stress theory. The parameter fitting results for the experimental phase change curves can also be interpreted as supporting more the new theory than existing traditional explanations.
Department of Biophysics, Faculty of Science, Kyoto University, Japan.
Y
Y
Kobuchi
T
T
Ito
A
A
Ogiwara
D002448:Cell Adhesion; D002465:Cell Movement; D003198:Computer Simulation; D004903:Erythrocyte Aggregation; D004912:Erythrocytes / Q000502:physiology*; D006801:Humans; D008433:Mathematics; D008954:Models, Biological