Red Cell Membrane Protein in Antibody Induced Haemolytic Anaemia

S ummary . Red cell stroma from nine cases of autoimmune haemolytic anaemia (AIHA) was extracted using dilute acetic acid. The isolated protein was then electrophoresed on 8 m urea starch gel. In six cases an absence of one band and absence or decreased intensity of a second band in the slowest moving group was observed. The pattern was the same as that of hereditary spherocytosis. Whereas these six cases demonstrated specific antibody activity, the other cases of AIHA in whom antibody specificity could not be demonstrated failed to show membrane electrophoretic alterations. The electrophoretic patterns of acetic acid extracted membrane protein obtained from red cells from Rh‐incompatible haemolytic disease of the newborn were similar to those cases of AIHA showing membrane protein alterations; that of ABO incompatible haemolytic disease of the newborn did not. Attempts to induce membrane protein alterations by exposing red cells to antibodies in vitro were unsuccessful.