Open Access The Murine Lung Microbiome Changes During Lung Inflammation and

Abstract: Most microbiome research related to airway diseases has focused on the gut microbiome. This is despite ad-vances in culture independent microbial identification techniques revealing that even healthy lungs possess a unique dy-namic microbiome. This conceptual change raises the question; if lung diseases could be causally linked to local dysbiosis of the local lung microbiota. Here, we manipulate the murine lung and gut microbiome, in order to show that the lung mi-crobiota can be changed experimentally. We have used four different approaches: lung inflammation by exposure to car-bon nano-tube particles, oral probiotics and oral or intranasal exposure to the antibiotic vancomycin. Bacterial DNA was extracted from broncho-alveolar and nasal lavage fluids, caecum samples and compared by DGGE. Our results show that: the lung microbiota is sex dependent and not just a reflection of the gut microbiota, and that induced inflammation can change lung microbiota. This change is not transferred to offspring. Oral probiotics in adult mice do not change lung mi-crobiome detectible by DGGE. Nasal vancomycin can change the lung microbiome preferentially, while oral exposure does not. These observations should be considered in future studies of the causal relationship between lung microbiota and lung diseases