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Isolation of a Soluble Resistance-Enhancing Factor from Mycobacterium phlei
A E Fox1, J Anschel, G L Evans
1Departments of Microbiology and Pharmaceutical Development, Warner-Lambert Research Institute, Morris Plains, New Jersey.
Abstract:
Fox, Alfred E. (Warner-Lambert Research Institute, Morris Plains, N.J.), Joachim Anschel, George L. Evans, Raam R. Mohan, and Benjamin S. Schwartz. Isolation of a soluble resistance-enhancing factor from Mycobacterium phlei. J. Bacteriol. 92:285-290. 1966.-Extraction of a crude cell wall preparation from Mycobacterium phlei with 20% urea yielded a fraction which induced a state of enhanced resistance to microbial challenge. The resulting soluble extract, after removal of the urea, represented a 15% yield of solids with the separation of the biologically active component(s) and elimination of toxicity. Single oral or subcutaneous submicrogram doses of this material induced a prolonged state of increased resistance to subsequent challenge with Salmonella enteritidis in mice. This effect appeared as early as 2 hr after oral administration and persisted for at least 30 days. Protection against experimental infection with Staphylococcus aureus was also demonstrated. Resistance to viral challenge with influenza type A was observed after intranasal administration of the M. phlei extract to mice. The isolated material was found to contain carbohydrate, protein, nucleic acids, and lipids. The lipids represented 60% of the total solids, and were all short-chain fatty acids. No toxic effects, including pyrogenicity, could be demonstrated after oral or parenteral administration of this preparation.
Insights
Researchers isolated a resistance-enhancing factor from Mycobacterium phlei. This soluble extract, administered in tiny doses, significantly boosted resistance to bacterial and viral infections in mice for over 30 days.
Area of Science:
- Microbiology
- Immunology
- Biochemistry
Background:
- Mycobacterium phlei cell wall preparations can be extracted to yield biologically active components.
- Previous research indicated potential for immune modulation by bacterial extracts.
Purpose of the Study:
- To isolate and characterize a soluble factor from Mycobacterium phlei that enhances resistance to microbial challenge.
- To evaluate the efficacy and duration of this resistance-enhancing effect in vivo.
Main Methods:
- Extraction of Mycobacterium phlei cell walls using 20% urea.
- Administration of the soluble extract (submicrogram doses) orally or subcutaneously to mice.
- Challenge studies using Salmonella enteritidis, Staphylococcus aureus, and influenza type A virus.
Main Results:
- A soluble extract was obtained with a 15% yield, containing carbohydrate, protein, nucleic acids, and lipids (60% short-chain fatty acids).
- Single submicrogram doses induced prolonged resistance to Salmonella enteritidis (onset 2 hr, duration >30 days) and Staphylococcus aureus.
- Intranasal administration conferred resistance to influenza type A virus.
- The preparation demonstrated no toxicity or pyrogenicity.
Conclusions:
- A non-toxic, resistance-enhancing factor can be isolated from Mycobacterium phlei.
- This factor effectively boosts innate immunity against a range of bacterial and viral pathogens in mice.
- The findings suggest potential therapeutic applications for immune modulation.
