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08:26
Measuring the 50% Haemolytic Complement (CH50) Activity of Serum
Published on: March 29, 2010
MECHANISM OF HEMOLYSIS BY COMPLEMENT : I. COMPLEMENT FIXATION AS AN ESSENTIAL PRELIMINARY TO HEMOLYSIS
1Department of Pediatrics and the Department of Pathology and Bacteriology, Johns Hopkins Medical School, Baltimore.
The Journal of General Physiology
|October 30, 2009
Summary
Red blood cell sensitization allows adsorption of complement, a crucial step for hemolysis. Electrolyte concentration and pH significantly influence complement fixation and hemolysis rates, impacting immune responses.
Area of Science:
- Immunology
- Biochemistry
- Cell Biology
Background:
- Sensitization of red blood cells (RBCs) by immune serum proteins enables complement adsorption.
- Complement adsorption to sensitized RBCs is a prerequisite for hemolysis.
Purpose of the Study:
- To investigate the mechanism of complement fixation by sensitized RBCs.
- To determine the influence of electrolytes and pH on complement fixation and hemolysis.
- To clarify the role of immune serum in hemolysis.
Main Methods:
- Studying complement adsorption to sensitized RBCs under varying electrolyte concentrations and pH levels.
- Observing the hemolytic action of complement in relation to sensitization and environmental factors.
Main Results:
- Complement adsorption (fixation) by sensitized RBCs is directly proportional to the degree of sensitization.
- Electrolyte concentration and pH critically affect complement fixation and subsequent hemolysis.
- Optimal conditions for complement fixation and hemolysis were identified (pH 6.5-8.0, specific electrolyte concentrations).
- Irreversible inactivation of complement occurred at extreme pH values (4.8 and 8.8).
Conclusions:
- Immune serum acts as an 'amboceptor,' mobilizing complement to the RBC surface.
- Complement fixation is the primary function of immune serum in hemolysis.
- The degree of sensitization dictates the efficiency of complement mobilization and hemolysis velocity.
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