Quantitative Determination of Antigen, Antibody and Complement in Precipitates

[摘要] 1. Immune sera to arsanil-azo-globulin were precipitated by small and by large amounts of antigen, in the presence of active and of inactivated guinea-pig serum. Gravimetric analysis of the precipitates demonstrated: 1. a) The weight of the precipitate obtained with active guinea-pig serum is greater. Maximally 0.15 to 0.20 mg of complement-protein were fixed per ml of guinea-pig serum. 2. b) The amount of complement protein in the precipitate was independent of the antigen-antibody ratio and equaled about 20 per cent of the weight of the precipitates. 3. c) Neither the antigen-antibody ratio nor the absolute amount of antigen or antibody in the precipitate is altered by complement fixation. 2. 2. Hemolysis of a single red cell requires approximately 10−11g, i.e. more than 1010 molecules of saponin or of sodium oleate. The same effect is produced by 1.5 × 10−14g, i.e. 60000 molecules of complement-protein. The much higher efficiency of complement supports the enzyme theory of complementary action.

[学科分类] 生物科学（综合）