Amoxicillin treatment of pneumococcal pneumonia impacts bone marrow neutrophil maturation and function.

ABSTRACT: Pneumonia caused by Streptococcus pneumoniae is a leading cause of death worldwide, and bacterial resistance to antimicrobial drugs has become a major issue. A growing body of evidence indicates that the successful treatment of bacterial infections results from synergy between antibiotic-mediated direct antibacterial activity and the host’s immune defenses. However, the mechanisms underlying the protective immune responses induced by amoxicillin (a β-lactam antibiotic used as the first-line treatment of S. pneumoniae infections) have not been characterized. A better understanding of amoxicillin’s effects on host-pathogen interactions might facilitate the development of other treatment options. Given the crucial role of neutrophils in the control of S. pneumoniae infections, we decided to investigate amoxicillin’s impact on neutrophil development in a mouse model of pneumococcal superinfection. Although a single therapeutic dose of amoxicillin prevented local and systemic inflammatory responses, it did not impair the emergency granulopoiesis triggered in the bone marrow by S. pneumoniae. Importantly, treatment of pneumonia with amoxicillin was associated with a greater mature neutrophil count in the bone marrow; these neutrophils had specific transcriptomic and proteomic profiles. Furthermore, amoxicillin-conditioned, mature neutrophils in the bone marrow had a less activated phenotype and might be rapidly mobilized in peripheral tissues in response to systemic inflammation. Thus, by revealing a novel effect of amoxicillin on the development and functions of bone marrow neutrophils during Streptococcus pneumoniae pneumonia, our findings provide new insights into the impact of amoxicillin treatment on host immune responses.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Streptococcus Pneumoniae Mus Musculus (mouse)

TISSUE(S): Neutrophil, Bone Marrow

SUBMITTER: SALIOU Jean-Michel  

LAB HEAD: Jean-michel Saliou

PROVIDER: PXD042496 | Pride | 2023-10-09

REPOSITORIES: Pride