A Pulmonary Lactobacillus murinus Strain Induces Th17 and RORγt+ Regulatory T Cells and Reduces Lung Inflammation in Tuberculosis.
J Immunol
; 207(7): 1857-1870, 2021 10 01.
Article
en En
| MEDLINE
| ID: mdl-34479945
ABSTRACT
The lungs harbor multiple resident microbial communities, otherwise known as the microbiota. There is an emerging interest in deciphering whether the pulmonary microbiota modulate local immunity, and whether this knowledge could shed light on mechanisms operating in the response to respiratory pathogens. In this study, we investigate the capacity of a pulmonary Lactobacillus strain to modulate the lung T cell compartment and assess its prophylactic potential upon infection with Mycobacterium tuberculosis, the etiological agent of tuberculosis. In naive mice, we report that a Lactobacillus murinus (Lagilactobacillus murinus) strain (CNCM I-5314) increases the presence of lung Th17 cells and of a regulatory T cell (Treg) subset known as RORγt+ Tregs. In particular, intranasal but not intragastric administration of CNCM I-5314 increases the expansion of these lung leukocytes, suggesting a local rather than systemic effect. Resident Th17 and RORγt+ Tregs display an immunosuppressive phenotype that is accentuated by CNCM I-5314. Despite the well-known ability of M. tuberculosis to modulate lung immunity, the immunomodulatory effect by CNCM I-5314 is dominant, as Th17 and RORγt+ Tregs are still highly increased in the lung at 42-d postinfection. Importantly, CNCM I-5314 administration in M. tuberculosis-infected mice results in reduction of pulmonary inflammation, without increasing M. tuberculosis burden. Collectively, our findings provide evidence for an immunomodulatory capacity of CNCM I-5314 at steady state and in a model of chronic inflammation in which it can display a protective role, suggesting that L. murinus strains found in the lung may shape local T cells in mice and, perhaps, in humans.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Tuberculosis Pulmonar
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Linfocitos T Reguladores
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Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares
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Células Th17
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Lactobacillus
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Pulmón
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Mycobacterium tuberculosis
Tipo de estudio:
Prognostic_studies
Límite:
Animals
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Humans
Idioma:
En
Revista:
J Immunol
Año:
2021
Tipo del documento:
Article