The Homologous Species Restriction of the Complement Attack: Structure and Function of the C8 Binding Protein
The homologous restriction of the complement attack, i.e., the inability of complement to lyse erythrocytes of the same species, has long been known (Bordet 1900), but only in the last decade has progress been made in understanding the nature of this phenomenon. It has become evident that the complement sequence is inhibited species-specifically on the membrane at two steps at least (Shin et al. 1986), thus protecting the erythrocytes against the complement attack. Inhibition is accomplished by two membrane proteins: one, the so-called decay accelerating factor (DAF) which inhibits the complement activation phase (Nicholson-Weller et al. 1982), and the other, the C8 binding protein (C8bp) which interferes with the action of the late complement components (Schönermark et al. 1984, 1986). Since the late complement components C5b-9 represent the cytolytic effector phase of complement, the following discussion will be restricted to the function and characterization of the C8bp.
KeywordsParoxysmal Nocturnal Hemoglobinuria Decay Accelerate Factor Erythrocyte Membrane Protein Paroxysmal Nocturnal Hemoglobinuria Patient Complement Attack
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