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Measuring the 50% Haemolytic Complement (CH50) Activity of Serum
Published on: March 29, 2010
STUDIES ON COMPLEMENT FIXATION : I. THE RATE OF FIXATION OF COMPLEMENT AT DIFFERENT TEMPERATURES
1Bureau of Laboratories of Michigan Department of Health, Lansing.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Complement fixation studies reveal antibody concentration dictates complement fixation rates. Most fixation occurs within the first hour and completes within four hours, regardless of temperature.
Area of Science:
- Immunology
- Biochemistry
Background:
- Complement fixation is a key immunological assay.
- Understanding factors influencing complement fixation is crucial for accurate serological testing.
Purpose of the Study:
- To investigate the kinetics of complement fixation.
- To determine the influence of antibody concentration and temperature on complement fixation.
Main Methods:
- Complement fixation studies were performed using protein antigens and specific immune rabbit sera.
- Experiments were conducted at various temperatures: ice box, room, and water bath.
Main Results:
- The rate of complement fixation is directly proportional to the concentration of antibodies in immune sera.
- The majority of complement fixation occurs within the first hour.
- Complement fixation is largely complete by 4 hours at ice box temperature.
- Temperature has minimal impact on the rate of complement fixation, with a slight increase observed at ice box temperature.
Conclusions:
- Antibody concentration is the primary determinant of complement fixation rate.
- The kinetics of complement fixation are rapid, with completion within hours.
- Standardizing incubation time and temperature is important for reproducible complement fixation assays.
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