"We have studied the links between individual bacterial species in the lung and markers in the host genome to identify genes that influence lung bacteria and may play a role in susceptibility to disease," explains Baines, who heads the Evolutionary Medicine working group at Kiel University (CAU) and at the Max Planck Institute for Evolutionary Biology in Plön. A total of seven genomic regions for eight bacterial traits were found. "We were able to identify several promising genes related to immune and inflammatory responses, lung functioning and disease susceptibility," says Baines. The paper, recently published in the journal Animal Microbiome, was also supported by the Cluster of Excellence "Precision Medicine in Chronic Inflammation" (PMI) and the Collaborative Research Centre "Origin and Function of Metaorganisms" (CRC 1182).
In the study, state-of-the-art molecular biological methods of analysis were used to quantify the bacterial species present in the lungs of the investigated mice, even with a low biomass. "Our study provides the first evidence for a role of host genetic variation contributing to variation in the lung microbiota," explains co-author Dr Meriem Belheouane from the Research Center Borstel, Leibniz Lung Center (FZB). The amount of Lactobacillus in the lungs was shown to be strongly associated with a specific region that contains the gene coding for the anti-inflammatory cytokine Interleukin 10. This finding was confirmed in animals in which the gene for Interleukin 10 (IL-10) was deactivated. Belheouane says: "IL-10 knockout mice had fewer Lactobacilli than the non-knockout animals." Host genetic variations were also found for the number of Pelomonas, another common bacterial species in the lungs. The functional significance of these bacterial species could potentially be used for future preventive or therapeutic purposes.
Despite major advances in diagnostics and treatment, lung diseases are on the rise worldwide and are among the most common causes of death. The aim of the Leibniz ScienceCampus for Evolutionary Medicine of the Lung (EvoLUNG) is to better understand the origin and development of chronic lung diseases such as tuberculosis or asthma. To this end, the scientists are working in interdisciplinary teams to investigate the spread and origin of multi-resistant pathogens in the lungs. On the other hand, they are researching the evolution of human gene variants that favour lung diseases, as well as the complex interaction of disease genes, microorganisms, pathogens and environmental factors in the development of lung diseases. In the long term, EvoLUNG aims to develop better diagnostics and improve therapies for diseases such as asthma, tuberculosis, cystic fibrosis or chronic bronchitis. A special focus is on preventing the development of resistance in the course of tuberculosis or cystic fibrosis as well as on a better understanding of the role of the body's own microbiota in the development of asthma. EvoLUNG is led by Professor Stefan Niemann from the Research Center Borstel (FZB) and, in addition to the FZB, also includes Kiel University (CAU) and the Max Planck Institute for Evolutionary Biology in Plön (MPI-EB).
MEDICA-tradefair.com; Source: Christian-Albrechts-Universität zu Kiel