Immune Hemolysis and the Functional Properties of the Second (C2) and Fourth (C4) Components of Complement

By use of the late-acting components of rat complement (rat C-EDTA) as a reagent for the lysis of the intermediate EAC142, each molecule of human C4 and of oxidized human C2 and one of every two molecules of human C2 taken up by the appropriate cell intermediates was shown to be hemolytically active. Furthermore, it was found that each molecule of guinea pig C2 in serum can be measured by its hemolytic activity.