Complement Hemolytic Activity Assay

**Semantic type:** Laboratory Procedure

**Definition:** A screening assay for circulating complement proteins in which diluted serum samples are added to antibody-coated erythrocytes and the percentage of cell lysis is measured. The values are expressed in hemolytic complement units per milliliter (CH50), the dilution of serum required to lyse 50 percent of the erythrocytes in the assay.

**Synonyms:** - CH50 - CH50 - CH50 - HEMOLYTIC COMPLEMENT ACTIVITY ASSAY - Total Hemolytic Activity Assay - Total Hemolytic Complement 50% - Total Hemolytic Complement Assay - Total Hemolytic Complement CH50