Hemolytic System

HEMOLYTIC SYSTEM, a combination of erythrocytes and their corresponding amboceptor. When complement is added to the H. s., dissolution of the erythrocytes occurs. The H. s. serves as an indicator for the presence of free complement and is applied in the complement fixation reaction (Borde-Jangu) and in the RW. Typically used are: sheep blood erythrocytes, as amboceptor—rabbit serum immunized with sheep erythrocytes, and complement serves as fresh guinea pig serum. Hemolytic serum is inactivated (for half an hour, at 55°) to destroy its own complement, and erythrocytes, after washing them from the serum, are used in the form of a suspension in physiological solution (see Wassermann reaction). The addition of the hemolytic system (so-called 2nd chain of the Borde-Jangu reaction or RW) serves as an indicator for detecting free complement in the 1st chain of these reactions (antigen + serum + complement). If in the 1st chain, due to the interaction of antigen and serum, binding, "fixation" of complement has occurred, then subsequently added hemolytic system will not find free complement for itself, and hemolysis will not take place—a positive reaction. A negative reaction—dissolution of erythrocytes—will occur in the case when the complement of the 1st chain remains free and combines with the amboceptor of the hemolytic system.