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Published on: September 28, 2016
Observations on the antibiotic treatment of experimentally induced mycoplasmal infections in mice
1Department of Medicine (Division A), Imperial College School of Medicine, St Mary's Hospital, Paddington, London W2 1NY, UK.
Abstract:
Antibiotics were given subcutaneously to female mice, colonized by mycoplasmas in the vagina and by others in the oropharynx. Mycoplasma pulmonis was eradicated from the vagina of 36 of 42 immunocompetent TO or BALB/c mice with oxytetracycline, and from 17 of 18 TO mice with lymecycline. Mycoplasma hominis was eradicated from the vagina of all of 18 immunocompetent BALB/c mice with oxytetracycline or tetracycline. Regarding oropharyngeal organisms, M. pulmonis was eradicated from only 20 of 42 TO or BALB/c mice with oxytetracycline and from none of 15 mice with lymecycline. However, Mycoplasma pneumoniae was eliminated from the oropharynx of eight of nine BALB/c mice with oxytetracycline. In contrast to the success in eradicating mycoplasmas from the vagina or oropharynx of immunocompetent BALB/c mice with oxytetracycline, no such effect was seen in nude BALB/c mice, indicating the importance of a competent immune system in conjunction with antibiotic treatment for eradication of these organisms.
Insights
Antibiotic treatment effectively eradicated vaginal mycoplasmas in immunocompetent mice. However, oropharyngeal mycoplasma eradication was less successful, highlighting the immune system's crucial role alongside antibiotics.
Area of Science:
- Microbiology
- Immunology
- Pharmacology
Background:
- Mycoplasma infections can colonize various sites in mammals.
- Antibiotic efficacy against Mycoplasma varies depending on the species and anatomical location.
- The role of the host immune system in Mycoplasma eradication is not fully understood.
Purpose of the Study:
- To evaluate the efficacy of subcutaneous antibiotics (oxytetracycline and lymecycline) in eradicating vaginal and oropharyngeal Mycoplasma colonization in mice.
- To investigate the influence of the host immune system on antibiotic treatment outcomes for Mycoplasma infections.
Main Methods:
- Female immunocompetent (TO and BALB/c) and nude BALB/c mice were subcutaneously administered oxytetracycline or lymecycline.
- Mice were colonized with Mycoplasma pulmonis in the vagina and oropharynx, and Mycoplasma pneumoniae in the oropharynx.
- Efficacy was assessed by determining the eradication rates of Mycoplasma from vaginal and oropharyngeal samples.
Main Results:
- Oxytetracycline eradicated Mycoplasma pulmonis from the vaginas of 36/42 immunocompetent mice and lymecycline from 17/18.
- Oxytetracycline or tetracycline eradicated Mycoplasma hominis from the vaginas of all 18 immunocompetent mice.
- Oropharyngeal M. pulmonis eradication was limited (20/42 with oxytetracycline, 0/15 with lymecycline).
- Oxytetracycline eliminated Mycoplasma pneumoniae from the oropharynx in 8/9 mice.
- No significant eradication was observed in nude mice, indicating immune system dependence.
Conclusions:
- Subcutaneous antibiotics, particularly oxytetracycline, are effective for vaginal Mycoplasma eradication in immunocompetent mice.
- Antibiotic efficacy against oropharyngeal Mycoplasma is lower and Mycoplasma pneumoniae appears more susceptible than Mycoplasma pulmonis.
- A competent immune system is essential for successful Mycoplasma eradication when combined with antibiotic therapy.
