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Rat polyarthritis: induction with adjuvants constituted with mycobacteria (and oils) from the environment
Abstract:
Mycobacteria inhabiting plants, soils and water can cause arthritis in rats. The list of arthritogenic mycobacteria from animal sources must also be extended. The arthritogenic activity is present in dead bacteria and resists extraction into ethanol-ether (1:1 v/v). Polyarthritis is only induced in conjunction with certain (oily) lipids = coarthritogens: some of these lipids are present in/on skin, intestines, etc. Isostearic acid is also a coarthritogen. Preliminary observations suggest the leprosy bacillus (M. leprae) is not arthritogenic but may confer immunity to the M. tuberculosis arthritogen. Some adjuvant-active corynebacteria/propionibacteria did not cause polyarthritis in 2 rat strains (DA, PVG) responding vigorously to mycobacterial arthritogens.
Insights
Certain mycobacteria cause arthritis in rats, requiring specific lipids called coarthritogens for induction. Dead bacteria retain arthritogenic activity, and Mycobacterium leprae may offer immunity against arthritis.
Area of Science:
- Microbiology
- Immunology
- Rheumatology
Background:
- Mycobacteria found in environmental sources like plants, soil, and water are known to induce arthritis in rats.
- The spectrum of arthritogenic mycobacteria, particularly those originating from animal sources, requires further elucidation.
- Arthritogenic activity has been observed in dead mycobacteria and is resistant to lipid extraction using ethanol-ether mixtures.
Purpose of the Study:
- To investigate the role of specific lipids (coarthritogens) in the induction of polyarthritis by mycobacteria.
- To explore the arthritogenic potential of various mycobacterial species and their components.
- To examine the potential immunomodulatory effects of Mycobacterium leprae on mycobacterial-induced arthritis.
Main Methods:
- Administration of mycobacteria and specific lipids to rat models (DA and PVG strains).
- Lipid extraction from bacterial preparations using ethanol-ether.
- Assessment of polyarthritis induction and severity.
Main Results:
- Polyarthritis induction necessitates the presence of coarthritogens, including oily lipids found in tissues like skin and intestines, and isostearic acid.
- Dead mycobacteria exhibit arthritogenic activity.
- Mycobacterium leprae did not appear to be arthritogenic but suggested a potential for conferring immunity against Mycobacterium tuberculosis-induced arthritis.
- Adjuvant-active corynebacteria and propionibacteria did not induce polyarthritis in susceptible rat strains.
Conclusions:
- Arthritogenic mycobacteria can originate from diverse environmental sources.
- Lipids act as crucial coarthritogens for mycobacterial arthritis induction.
- Mycobacterium leprae may possess immunoprotective properties against arthritis, warranting further investigation.