The erythrocyte membrane site for the effect of temperature on osmotic fragility.

The osmotic fragility of human erythrocytes is well known to decrease as the temperature is elevated. The cellular site for the temperature effect was studied by assessing possible roles of hemoglobin and of membrane lipids and by taking advantage of the unique response of camel erythrocytes to temperature. It is concluded that the erythrocyte membrane is the site for the temperature effect on osmotic fragility. The human erythrocyte is likely to rupture in protein--lipid boundary regions in the membrane, from which cholesterol is apparently excluded.