The red blood cell membrane consists of a lipid bilayer, containing transmembrane proteins with various functions. The membrane is linked to the cytoskeleton of the RBC, which consists of long twisted strands of alpha and beta spectrin and actin filaments. Spectrin forms the inner shell of the RBC and gives the cell its deformability. Defects in this protein results in abnormal RBC shapes and the condition of hereditary spherocytosis in human beings. Spectrin is bound to the membrane at sites containing the anion exchanger, band 3 via cytoskeletal proteins, ankyrin and adducin. Some of the transmembrane proteins (such as glycophorin A, Kell and Duffy, are RBC antigens (and in the case of glycophorin A, form a blood group system separate from ABO) in human beings.
Republished with permission from the American Society of Hematology from “Anatomy of the red blood cell membrane skeleton: unanswered questions” by Samuel E Lux IV, Blood, volume 127, issue 2, pages: 187-199, 2016; permission conveyed through Copyright Clearance Center, Inc .
