Abstract

The increasing prevalence of allergic airway diseases in industrialized countries has been associated with high hygienic standards and reduced microbial exposure. Probiotic lactic acid bacteria, such as certain <i>Lactobacillus</i> strains, were shown to have potentially beneficial immunomodulatory properties. Therefore, we determined the effect of intranasal administration of <i>L. rhamnosus</i> GG (LGG) and GR-1 (LGR-1) in a mouse model of birch pollen-induced allergic asthma. The symptoms of allergic asthma were induced with 7 intranasal applications with 1- or 2-day interval with birch pollen extract. The asthma induction protocol was preceded by 8 intranasal administrations of LGG or LGR-1 at a concentration of 5 x 10<sup>8</sup> CFU/dose over the course of two weeks on four consecutive days each week. We assessed serum antibody levels, bronchoalveolar lavage (BAL) cell counts, lung histology, lung cytokine levels, airway hyperreactivity. LGG administration resulted in a significant decrease in allergic airway inflammation (BAL eosinophils, lung IL-13 and IL-5 levels) and a significantly reduced number of respiratory exacerbations. Contrary to LGG, no decisive results were obtained for LGR-1. Longitudinal <i>in vivo</i> lung micro-computed tomography (micro-CT) is currently ongoing to determine inflammatory exacerbation. Complementary to micro-CT, fluorescence imaging (FLI) of a fluorescent LGG strain will be performed to understand the probiotic-host interactions at the whole-body and whole-organ level. In conclusion, bacterial strain-specific beneficial effects of intranasally administered LGG were observed in a mouse model of birch pollen-induced allergic asthma.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.