The bacterial extract Broncho-Vaxom protects against respiratory infections - in vivo and in vitro studies

The bacterial extract Broncho-Vaxom (OM-85 BV) given orally to patients is used for the prevention and treatment of respiratory tract infections. We investigated OM-85 BV efficacy against viral and bacterial infections in murine models. We first evaluated its role of protecting from an A/PR/8/34 (H1N1) influenza virus infection. In a group treated with OM85 BV all animals survived, compared to 70% in the untreated control. 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. We have also shown the capacity of OM-85 BV to behave as a general immunomodulator, e.g. its macrophage stimulatory effect by monitoring the NO release in bone marrow derived macrophages. To further explore the mode of action of OM-85 BV, in vitro analysis of biological material of mouse treated with BV revealed an increase of bacteria specific IgA in supernatants of Peyer's patches and mesenteric lymph nodes derived cell cultures. Thus, this report again demonstrates the antimicrobial activity of Broncho-Vaxom.