TB Research

Stress-responsive <i>Mycobacterium tuberculosis</i> subpopulations manipulate macrophage polarization and can be targeted to limit inflammation

Laura Pokorny, Lalit Kumar Singh, Nicolas Gangneux, M. Pillon, Claudia Chica, Natalia Pietrosemoli, E. Perthame, José Crispin Zavala Alvarado, et al. (23 authors)

bioRxiv (Cold Spring Harbor Laboratory) · 2026-03

Abstract

Summary Tuberculosis is characterized by broad clinical heterogeneity that hinders infection control, with differences in lesion development, progression, and treatment outcomes. This complexity is likely associated with Mycobacterium tuberculosis inherent phenotypic variation and its capacity to diversify under host microenvironmental and antimicrobial stressors. Here, we analyze M. tuberculosis at the single-cell and subpopulation level using fluorescent reporters, imaging, transcriptomic, and functional assays. We identify RNA signatures specific to stress-responsive bacilli with translational potential. Focusing on the clinically validated chaperone GroEL2, we find that it correlates with M. tuberculosis growth rate and stress tolerance in vitro and intracellularly. Furthermore, GroEL2 phenotypic diversity influences innate responses in macrophages, which experience different polarization, in turn affecting GroEL2 expression. We also show that targeting GroEL2 impairs pathogen survival and dampens inflammation. This study provides a link between pathogen phenotypic variation and macrophage fates, with implications for early infection outcomes, local disease progression, and subpopulation-targeted interventions.

MeSH terms

  • Phenotype
  • Biology
  • Pathogen
  • Macrophage polarization
  • Inflammation
  • Innate immune system
  • Disease
  • Immunology
  • Macrophage
  • Cell biology
  • In vitro
  • Tuberculosis
  • Immune system
  • RNA
  • Mycobacterium tuberculosis