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A CHEMICAL STUDY OF THE SPECIFIC ELEMENTS OF TUBERCULIN. I
1Department of Bacteriology and Immunology, Harvard University Medical School, Boston.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Old tuberculin contains two distinct substances responsible for different reactions. A non-protein gum causes precipitin reactions, while a protein likely causes skin reactions, necessitating revised standardization methods.
Area of Science:
- Immunology
- Biochemistry
Background:
- Old tuberculin is a complex biological preparation used in diagnostics.
- Its biological activity is attributed to multiple components, leading to varied reactions.
Purpose of the Study:
- To differentiate the substances in old tuberculin responsible for specific immunological reactions.
- To clarify the nature of the components causing precipitin and skin reactions.
- To evaluate the suitability of current tuberculin standardization methods.
Main Methods:
- Analysis of old tuberculin to isolate and identify active components.
- Characterization of substances based on their chemical properties (protein vs. non-protein).
- Correlation of isolated substances with observed immunological responses (precipitin and skin reactions).
Main Results:
- Two distinct substances in old tuberculin were identified.
- A non-protein gum was found to be responsible for the precipitin reaction.
- A protein component was identified as the likely cause of the skin reaction.
Conclusions:
- The precipitin and skin reactions elicited by old tuberculin are mediated by separate entities.
- Current methods for standardizing tuberculin using precipitin or complement fixation assays require re-evaluation.
- Further research is needed to fully elucidate the protein responsible for skin reactivity.
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