GM-CSF controls Mycobacterium tuberculosis infection by limiting type I IFN-driven neutrophil extracellular trap formation [Blood]

ABSTRACT: Tuberculosis (TB) remains the world’s top infectious killer. Understanding how immune mediators determine the outcome of Mycobacterium tuberculosis infection could facilitate the design of better therapies against this devastating disease. GM-CSF mediates protective immunity against TB but the underlying mechanisms remain elusive. To determine the molecular mechanisms underlying the protective role of GM-CSF during M. tuberculosis infection we performed RNA-sequencing analyses of whole blood and lung samples obtained from C57Bl/6 mice infected with HN878 and treated with anti-GM-CSF monoclonal antibody or isotype control. Uninfected mice were also treated and used as uninfected controls. Three weeks post-infection, whole blood and lungs were harvested from each individual mouse and processed for RNA-sequencing. Transcriptomic analyses revealed that during M. tuberculosis infection GM-CSF regulates the expression of genes associated with neutrophil recruitment and activation and type I IFN-inducible genes, which have been previously associated with TB pathogenesis. Further mechanistical studies showed that disease exacerbation driven by GM-CSF blockade during M. tuberculosis infection was type I IFN and neutrophil-dependent and that over-activation of neutrophils by type I IFN induced NET formation at the site of infection. NETs were also found in necrotic lung lesions from patients with pulmonary TB and type I IFN-driven NET formation correlated with increased disease susceptibility in different mouse models of TB. Our findings reveal an important immune network that may play a central role in determining TB outcome.

ORGANISM(S): Mus musculus

PROVIDER: GSE141192 | GEO | 2020/09/07

REPOSITORIES: GEO