Serum Amyloid A proteins reduce bone mass during mycobacterial infections

Osteopenia has been associated to several inflammatory conditions, including mycobacterial infections. How mycobacteria cause bone loss remains elusive, but direct bone infection may not be required. Using genetically engineered mice and morphometric, transcriptomic and functional analyses, we aimed to identify the molecular mechanisms responsible for bone loss during mycobacterial infections. Overall, our results report a novel crosstalk between the cytokine network operating in macrophages and bone homeostasis and disclose SAA proteins as potential biomarkers of bone loss during infection by mycobacteria.