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Updated: Jun 19, 2026
08:26
Measuring the 50% Haemolytic Complement (CH50) Activity of Serum
Published on: March 29, 2010
THE MECHANISM OF COMPLEMENT FIXATION.
1Department of Pathology and Bacteriology, Johns Hopkins Medical School, Baltimore.
The Journal of General Physiology
|October 30, 2009
Summary
Complement fixation in antigen-antibody reactions is an adsorption process. This immune reaction involves globulin aggregation on antigens, similar to other adsorption phenomena.
Area of Science:
- Immunology
- Biochemistry
Background:
- Complement fixation is a key indicator in antigen-antibody reactions.
- Understanding the mechanism of complement fixation is crucial for immunological assays.
Purpose of the Study:
- To elucidate the fundamental mechanism of complement fixation in antigen-antibody reactions.
- To compare the physical constants of complement fixation with known adsorption processes.
Main Methods:
- Investigated complement fixation across various antigen-antibody reactions involving heterogeneous phases (e.g., red cells, bacteria, precipitates).
- Analyzed physical constants including temperature coefficient, velocity, and reactant stoichiometry.
- Examined the aggregation of immune-serum globulins on antigen surfaces.
Main Results:
- Complement fixation occurs in all antigen-antibody reactions with a heterogeneous phase.
- Physical constants of complement fixation align with those of adsorption processes.
- Immune reactions involve globulin aggregation on antigens, with complement fixation acting as an adsorption to these aggregates.
Conclusions:
- Complement fixation is fundamentally an adsorption phenomenon, irrespective of the aggregate's form (precipitate or surface film).
- The high avidity of immune aggregates for complement may stem from specific chemical affinity or physical properties.
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