Specific erythrocyte adhesion energy determination through rotational viscometry

ALTUBE, VALVERDE, RASIA RJ

Mendoza

Congreso; Saib; 2003

Erythrocyte adhesion provides an experimental model for the study of intercellular interactions. We present a simple reo-mecchanic technique to determine the specific adhesion energy between adjacent cells consisting in plotting curves of viscosity vs. fluid shear stress obtained for red cells suspensions using a rotational cone-plate viscometer Brookfield LVDIII+ and different shear rates at 23 C. Such curve, plotted in a semi-logarithmic scale, exhibits a linear segment with negative slope, followed by a segment that converges asymptotically to the minimum apparent viscosity of the suspension. Extrapolating the linear section of the curve to intercept the value of minimum viscosity, a critical value of shear stress is obtained, at which total dissociation of cellular doublets is achieved. Specific energy is calculated using the Derjaguin relation for rotational flow. Specific energy quantification allows to estimate even a weak intercellular adhesion strength, and also to analyze the fluctuations of this parameter in circulatory pathologies.