The role of membrane lipids in the survival of red cells in hereditary spherocytosis

The relationship of red cell membrane lipid content to red cell morphology and survival in patients with liver disease

The relationship of red blood cell (RBC) membrane lipid content to RBC morphology and survival was studied in patients with liver diseases. An increase in RBC cholesterol and phospholipid was detected in most patients with hepatocellular disease or cholestatic jaundice but the alteration in RBC lipid content did not correlate with RBC survival. The main abnormality of RBC morphology observed was the presence of macrocytes and target cells. In a small proportion of patients (approximately 3%) with severe hepatocellular disease, significant numbers of severely deformed ("spur") cells were seen. In these patients haemolysis was moderately severe and the RBC lipid profile showed increased membrane cholesterol without a concomitant increase in phospholipids. It is concluded that only in patients with "spur" cell anaemia do the morphological alterations lead to premature removal of cells from the circulation. The cause of the shortened RBC survival in jaundiced patients without "spur" cells remains to be determined.

An analysis of lipoproteins, bile acids, and red cell membranes associated with target cells and spur cells in patients with liver disease

Most patients with stable cirrhosis of the alcoholic have "target" red cells; however, a minority have "spur" cells and severe hemolytic anemia. These two syndromes were studied in 27 patients with target cells and 17 patients with spur cells, all of whom had advanced cirrhosis. The cholesterol and phospholipid content of red cell membranes effectively distinguished target cells from spur cells. Target cells alone were rich in lecithin, and both the cholesterol/phospholipid and cholesterol/lecithin mole ratios were greater in spur cells. The cholesterol/phospholipid mole ratio of both types of red cells correlated closely with the free cholesterol saturation of serum lipoproteins, as defined by the amount of free cholesterol relative to phospholipid and protein in these lipoproteins. Lecithin: cholesterol acyltransferase (LCAT) activity was decreased in most patients with target cells and spur cells; however, the relationship between this activity and the lipid abnormalities observed was weak. Serum bile acid levels also correlated poorly with serum and cell lipids. However, in patients with target cells the amount of cholic and deoxycholic acids in serum was approximately equal to the amount of chenodeoxycholic acid, whereas in patients with spur cells chenodeoxycholic acid (the precursor of lithocholic acid) predominated.

Red cell survival studies in hereditary spherocytosis

The in vivo survival of hereditary spherocytes has been investigated with the (51)Cr red cell survival technique. Spherocytes invariably showed a shorter survival in a normal recipient than in the donor's own circulation. Moreover transfusion of spherocytes from a mother to her son, both with hereditary spherocytosis, showed that "foreign" spherocytes have a shorter survival than the "self" spherocytes of the recipient. These findings are attributed to splenic reticuloendothelial blockade, specific towards hereditary spherocytes in the patient's own circulation. There was no correlation between the Na(+) influx and the hemolytic tendency of hereditary spherocytes when the latter was measured by the survival t(1/2) in compatible normal recipients. However osmotic fragility influenced cell survival since cells with high fragility were rapidly sequestered in the normal spleen. It is suggested that both cell shape and a selective reticuloendothelial blockade in the spleen are important factors in determining the severity of hemolysis in the individual patient.