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Toxic properties of the Mycoplasma arthritidis ISR-1 membrane
Abstract:
Isolated membranes of Mycoplasma arthritidis ISR-1 possess toxic properties for rats, mice and chicken embryos. Reactions are dose-dependent. By intravenous injection of 20 mg of membrane protein, a lethal toxicity syndrome resembling shock is induced in Sprague-Dawley rats of 100 g body weight. Mice of approximately 20-g body weight show the same syndrome by intravenous injection of 15 mg of membrane protein. The lethal toxicity for chicken embryos increases from 10 to 80% after injection of 0.3 to 1.5 mg of membrane protein. The LD50 in chicken embryos was found to be 0.5 mg membrane protein. After administration of 10-15 mg of membrane protein, rats showed an increase in temperature from 38 to 41 degrees C within 5 h. Because of the difficulty in measuring the temperature in mice, loss of body weight was taken as the criterion for toxicity. Body weight was reduced up to 16% within 1 day after intravenous injection of 500 micrograms of membrane protein per g of body weight. For sheep red blood cells, M. arthritidis ISR-1 membranes were haemolytic in concentrations of 4 mg of membrane protein and higher. Intradermal injection of 1 mg of membrane protein into guinea-pigs resulted in red swelling reactions measuring approximately 10 mm in diameter 10 h after injection. For foetal rat skin fibroblasts, M. arthritidis ISR-1 membranes were toxic in concentrations from 1 micrograms (3H-uridine incorporation), 10 micrograms (14C-leucine incorporation) and 100 micrograms (3H-thymidine incorporation) of membrane protein.
Insights
Mycoplasma arthritidis ISR-1 membranes exhibit dose-dependent toxicity in rats, mice, and chicken embryos, causing lethal shock, fever, and weight loss. These membranes also induce hemolytic and skin reactions, and are toxic to rat fibroblasts.
Area of Science:
- Microbiology
- Immunology
- Toxicology
Background:
- Mycoplasma arthritidis is a pathogen known to cause various infections.
- The pathogenic mechanisms of Mycoplasma species are not fully understood.
- Membrane components of microorganisms can possess significant biological activity.
Purpose of the Study:
- To investigate the toxic properties of isolated membranes from Mycoplasma arthritidis ISR-1.
- To determine the dose-dependent effects of these membranes in various animal models and cell cultures.
Main Methods:
- Intravenous and intradermal injections of Mycoplasma arthritidis ISR-1 membranes into rats, mice, guinea pigs, and chicken embryos.
- Monitoring of physiological parameters including lethality, body temperature, body weight loss, and skin reactions.
- In vitro assays using sheep red blood cells for hemolytic activity and foetal rat skin fibroblasts for cytotoxicity.
Main Results:
- Mycoplasma arthritidis ISR-1 membranes induced a lethal toxicity syndrome resembling shock in rats and mice, and increased mortality in chicken embryos.
- Dose-dependent effects were observed, with LD50 determined in chicken embryos.
- Rats exhibited fever, while mice showed body weight loss. Hemolytic activity against sheep red blood cells and skin reactions in guinea pigs were also noted.
- Membranes demonstrated cytotoxicity to foetal rat skin fibroblasts in vitro.
Conclusions:
- Isolated membranes of Mycoplasma arthritidis ISR-1 possess significant toxic properties.
- These toxic effects are demonstrated across multiple biological systems, suggesting a potent biological activity of the membrane components.
- Further research is warranted to identify the specific toxic molecules within the Mycoplasma arthritidis ISR-1 membranes.