Shape Changes in Human Erythrocytes Induced by Replacement of the Native Phosphatidylcholine with Species Containing Various Fatty Acids

• Published in: The Journal of cell biology Vol. 99; no. 6; pp. 2260 - 2267
• Main Authors: Kuypers, F. A., Roelofsen, B., Berendsen, W., J. A. F. Op Den Kamp, Van Deenen, L. L. M.
• Format: Journal Article
• Language: English
• Published: New York, NY Rockefeller University Press 01.12.1984; The Rockefeller University Press
• Subjects: Biological and medical sciences; Cell membranes; Cell morphology; Chemical composition; Erythrocyte membrane; Erythrocyte Membrane - ultrastructure; Erythrocytes; Erythrocytes - ultrastructure; Fatty acids; Fatty Acids - blood; Fundamental and applied biological sciences. Psychology; Humans; Lipids; Membrane Lipids - blood; Microscopy, Electron; Molecular and cellular biology; Molecules; P branes; Phosphatidylcholines; Phosphatidylcholines - blood; Phospholipids; Structure-Activity Relationship; Human; Blood cell; Regulation(control); Morphology; Red blood cell; Phospholipid; Fatty acids
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.99.6.2260

Phosphatidylcholine-specific transfer protein from beef liver has been used to replace native phosphatidylcholine (PC) molecules from intact human erythrocytes by a variety of PC species differing in fatty acid composition. These replacements changed neither the total phospholipid content of the membrane, nor the composition of this fraction in terms of the various phospholipid classes. The morphology of the erythrocyte was not modified when native PC was replaced by 1-palmitoyl,2-oleoyl PC, 1-palmitoyl,2-linoleoyl PC, egg PC, or PC isolated from rat liver microsomes. Replacement with the disaturated species 1,2-dimyristoyl PC, 1,2-dipalmitoyl PC, and 1,2-distearoyl PC resulted in the formation of echinocytes and, at higher levels of replacement, in spheroechinocytes. Echinocyte-like erythrocytes were also observed after replacement with 1-palmitoyl,2-arachidonoyl PC, whereas stomatocytes were formed upon replacement with PC species containing two unsaturated fatty acids, e.g., 1,2-dioleoyl PC and 1,2-dilinoleoyl PC. The observations show that the erythrocyte membrane structure and the overall discoid cell shape of the human erythrocyte are optimally stabilized by PC species that contain one saturated and one mono- or diunsaturated fatty acid, and that the cell tolerates only limited variations in the species composition of its PC.