Detection of complement components on unlysed erythrocytes from acid hemolysis and thrombin test reactions in paroxysmal nocturnal hemoglobinuria.

Abstract

As a result of an unidentified erythrocyte defect red cells from patients with paroxysmal nocturnal hemoglobinemia (PNH) are susceptivle to hemolysis in acidified fresh serum. This acid hemolysis reaction is augmented by commercial bovine thrombin. The role of serum complement in these reactions has not been entirely clear. Accordingly antiglobu- lin test were performed on PNH erythrocytes surviving hemolysis in these systems and these cells were found to be coated with complement. PNH erythrocytes surviving thrombin test hemolysis were coated with [beta]lc-globulin and lE. -globulin and thus resemble normal cells surviving hemolysis in erythrocytes-antibody-complement systems. This suggests a role of complement-fixing antibodies known to be present in commercial bovine thrombin preparations. PNH erythrocytes surviving acid hemolysis, in contrast, are coated with [beta]lC-globulin but not [beta]lE-globulin. These results are consistent with a hypothesis of direct interaction of subcomponents of the 3rd complement component and the intrinsically defective PNH erythrocyte to account for the increased sensitivity of this cell to complement damage.