Sickling of sickle erythrocytes does not alter phospholipid asymmetry

Experiments in which phospholipase A2 has been used to examine the accessibility of phospholipids on the surface of sickled erythrocytes and of spectrin-free spicules derived from these cells have shown that accessibility is essentially unchanged compared with oxygenated sickle or normal erythrocytes. These results conflict with the claims of other workers that sickling is accompanied by loss of lipid asymmetry and that spectrin is important in maintaining the normal distribution of phospholipids in the erythrocyte membrane.