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06:29
Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells
Published on: January 29, 2014
THE INTERFERENCE OF INACTIVE SERUM AND EGG-WHITE IN THE PHENOMENON OF COMPLEMENT FIXATIONS
1Laboratories of the Rockefeller Institute for Medical Research, New York.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Non-complementary proteins can remove fixing properties in syphilis and Bordet-Gengou reactions. Serum fixability, crucial for quantitative serology, depends on complementary activity and volume, not just species.
Area of Science:
- Immunology
- Serology
Background:
- The phenomenon of molecular fixation in serological reactions, such as those for syphilis and Bordet-Gengou, involves complex interactions.
- The presence of non-complementary proteins can interfere with or alter the observed fixation properties and complementary activity.
Purpose of the Study:
- To investigate the influence of non-complementary proteins on the fixing property of syphilitic serum and precipitates.
- To understand the factors affecting serum fixability and its implications for quantitative serological assays.
Main Methods:
- Addition of non-complementary proteins (blood serum, hen's egg) to syphilitic serum and specific precipitates.
- Observation of changes in complementary activity and fixation phenomena.
- Thermal and chemical treatments (heating, alcohol coagulation, boiling) of sera and proteins to assess their properties.
Main Results:
- Non-complementary proteins removed the fixing property and complementary activity in syphilis and Bordet-Gengou reactions.
- Serum fixability is influenced by factors beyond just the presence of complement, including species-specific constants.
- Heating sera above 56°C reduced fixability, with total loss at 85°C; coagulation destroyed interfering properties.
Conclusions:
- Fixation is not exclusively directed towards complement, necessitating consideration of both complementary and volumetric unity for accurate quantitative serology.
- A formula (X = (K * P) / V) is proposed to determine serum suitability, incorporating species constant (K), complementary activity (P), and serum volume (V).
- Further studies are needed to identify species yielding optimal values for serum suitability in serological testing.
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