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Published on: April 14, 2011
The bacterial extract OM-85 BV protects mice against influenza and Salmonella infection
Wolfgang G Bessler1, Ulrich Vor dem Esche, Noel Masihi
1Institute for Molecular Medicine and Cell Research, University Clinic, Freiburg, Germany. wolfgang.bessler@mol-med.uni-freiburg.de
Abstract:
The bacterial extract OM-85 BV has been shown to provide protection against recurrent respiratory infections. We here investigated its efficacy against viral and bacterial infections in murine models. We first evaluated the role of OM-85 BV protecting from an A/PR/8/34 (H1N1) influenza virus infection. In a group treated with 1.75 mg/mouse OM-85 BV all animals survived, compared to 70% in the untreated control group and a group treated with a lower dosage. In addition, the appearance of clinical signs was delayed, their intensity was decreased, and they disappeared faster; also a marked increase in the influenza hemagglutination inhibition antibody level was observed. Since bacterial infections often superimpose viral lung infections, we also investigated on the protection of mice from a Salmonella typhimurium infection after the oral administration of OM-85 BV. Here, 100% of the OM-85 BV treated animals survived compared to 58% of the untreated control group. The mechanism of protection was further investigated: OM-85 BV acts, on the one hand, as an immunogen: the repeated administration of OM-85 BV induced a marked increase in serum antibody levels recognizing pathogenic bacterial strains. On the other hand, the extract acts as a stimulator of the nonspecific macrophage, monocyte, dendritic cell, and granulocyte response. Our findings demonstrate the antimicrobial activity of OM-85 BV against infections, as also has been shown in clinical studies.
Insights
The bacterial extract OM-85 BV enhances survival against influenza and Salmonella infections in mice. This immune stimulant boosts antibody levels and activates key immune cells, demonstrating broad antimicrobial efficacy.
Area of Science:
- Immunology
- Microbiology
- Pharmacology
Background:
- Recurrent respiratory infections pose a significant health burden.
- Bacterial infections frequently complicate viral respiratory illnesses.
- The bacterial extract OM-85 BV is known to offer protection against respiratory infections.
Purpose of the Study:
- To investigate the efficacy of OM-85 BV against viral (influenza) and bacterial (Salmonella typhimurium) infections in murine models.
- To elucidate the underlying mechanisms of protection conferred by OM-85 BV.
Main Methods:
- Murine models were infected with A/PR/8/34 (H1N1) influenza virus or Salmonella typhimurium.
- Mice were treated with OM-85 BV at a dosage of 1.75 mg/mouse.
- Survival rates, clinical signs, antibody levels (hemagglutination inhibition), and immune cell responses (macrophages, monocytes, dendritic cells, granulocytes) were assessed.
Main Results:
- OM-85 BV treatment resulted in 100% survival against influenza and Salmonella infections, compared to 70% and 58% in controls, respectively.
- Clinical signs of influenza were delayed, less severe, and resolved faster in treated mice.
- OM-85 BV administration significantly increased influenza hemagglutination inhibition antibody levels and induced a robust immune cell response.
Conclusions:
- OM-85 BV demonstrates significant protective efficacy against both viral and bacterial infections in preclinical models.
- The extract acts as an immunogen, increasing specific antibody levels, and as a stimulator of innate immune cells.
- These findings support the clinical use of OM-85 BV for preventing and treating recurrent respiratory tract infections.
