complement binding assay


com·ple·ment fix·a·tion

1. antigen-antibody interactions cause a conformational shift in immunoglobulin structure promoting binding of C1 and subsequent activation of the complement cascade, that is, complement fixation.
See also: Bordet-Gengou phenomenon, Wassermann test.
2. an immunoassay using reference antibodies with complement fixation and lysis of red blood cells as an indicator of detectable antigen. The degree of hemolysis affects the optic density of the sample, which can be measured and compared with a standard reference concentration curve.
See also: Bordet-Gengou phenomenon, Wassermann test.
Synonym(s): CF test, complement binding assay

com·ple·ment bind·ing as·say

(kom'plĕ-mĕnt bīnd'ing as'ā) A test for the detection of immune complexes.