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Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells
Published on: January 29, 2014
THE ACTIVATING EFFECT OF MAGNESIUM AND OTHER CATIONS ON THE HEMOLYTIC FUNCTION OF COMPLEMENT
M M Mayer1, A G Osler, O G Bier
1Department of Medicine, College of Physicians and Surgeons, Columbia University, and the Presbyterian Hospital, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Magnesium (Mg++) is essential for complement-mediated hemolysis, significantly enhancing this process. Tissue fluids enhance hemolysis by providing Mg++, and its deficiency can be overcome by supplementation.
Area of Science:
- Immunology
- Biochemistry
Background:
- The complement system is crucial for immune responses, involving a cascade of proteins.
- Hemolytic activity is a key indicator of complement system function.
- The role of divalent cations in complement activation is not fully elucidated.
Purpose of the Study:
- To investigate the essentiality of magnesium (Mg++) and other cations in complement-mediated hemolysis.
- To determine the contribution of tissue fluids to hemolytic activity.
- To understand the mechanism of anticomplementary substances.
Main Methods:
- Experimental hemolytic assays were performed using varying concentrations of cations.
- The effect of tissue fluids on hemolytic activity was analyzed.
- The interaction of chelating agents with Mg++ and Ca++ in the hemolytic system was studied.
Main Results:
- Magnesium (Mg++) is essential for hemolytic activity, with other cations like Ca++, Ni++, and Co++ showing less efficacy.
- Supplementation with Mg++ significantly enhances hemolytic activity, indicating its limiting role in standard systems.
- Tissue fluids enhance hemolysis due to their Mg++ content, and Mg++ can overcome the anticomplementary effects of chelating agents.
Conclusions:
- Magnesium (Mg++) plays a critical, essential role in the complement-mediated hemolytic pathway.
- The presence of sufficient Mg++ is vital for optimal complement function.
- Calcium (Ca++) may also contribute to lysis, but to a lesser extent than Mg++.
Keywords:
COMPLEMENT
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