Prevention of in vitro sickling of human erythrocytes by monofunctional amidination

Abstract

Treatment of sickle erythrocytes with the monoimidate, ethylacetimidate, prevented anoxia-induced sickling in vitro. Hemoglobin isolated from amidated erythrocytes exhibited an increase in the minimum gelling concentration compared to untreated preparations. Although the prevention of sickling did appear to involve chemical modification of hemoglobin S, an increase in the oxygen affinity was not a requisite for the antisickling activity of the imidates. Our results suggest that substitution of amidino for amino groups prevents the aggregation of deoxyhemoglobin S. Furthermore, comparison of monoimidates with bifunctional reagents indicates that molecular crosslinking is not essential for antisickling activity.