Comprehensive CyTOF and lipidomic analysis of splenic immune and serum lipid responses to BCG vaccination and H37Rv challenge in BALB/c mice

Résumé fourni par la source

The protective efficacy of the Bacillus Calmette-Guérin (BCG) vaccine against Mycobacterium tuberculosis (Mtb) is variable, and the systemic mechanisms linking cellular immunity with host metabolism remain poorly understood. This study employed high-dimensional mass cytometry (CyTOF) within the splenic compartment and serum lipidomics to map the integrated immuno-metabolic landscape in BCG-vaccinated and non-vaccinated mice following infection with the H37Rv strain. We report that BCG vaccination was associated with a distinct phenotype characterised by the priming of antimicrobial myeloid subsets (CD11b+ Mac2+/Mac3+) and lipidomic pathways away from stress-induced inflammatory responses. In contrast, non-vaccinated hosts exhibited a dysregulated response, characterised by a systemic cortisol surge, a lipidomic profile suggestive of reduced bioactive lipids (including PPARγ ligands such as 13-HODE and 19,20-DiHDPA), and the reactive mobilisation of CD103 + CD4+/CD8 + T cells and activated B cell subsets to the spleen. These findings reveal that protection is not solely cellular but relies on a stable metabolic environment that supports immune function. While infection in naive hosts drives a resource-depleting stress response that likely compromises macrophage efficacy, BCG vaccination establishes an integrated multiparametric defence, preventing pathogen-driven metabolic manipulation and maintaining the necessary lipid mediators for effective inflammation resolution and bacterial control.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.