Studies on the mechanism of erythrocyte aging and destruction I. Separation of rat erythrocytes according to age by ficoll gradient centrifugation

Abstract

A 22–34% linear Ficoll gradient is described for use in separating red blood cells of different ages. Newly synthesized, 59Fe-labeled red cells were found in the top fractions of the gradient, and these cells moved down toward the lower part of the gradient as they became older. The Ficoll gradient method gave a higher resolution compared to existing published methods. Red blood cells with increasing density, increasing sphericity and decreasing volume were separated by the Ficoll gradient method. The protein content remained constant in red cells up to about two weeks of age, and then showed a trend to decrease with age. Changes in density, shape, volume, and probably protein content, are characteristics of aging red cells.