Colonization with Helicobacter is concomitant with modified gut microbiota and drastic failure of the immune control of Mycobacterium tuberculosis

Laleh Majlessi (1, 2) , Fadel Sayes (1, 2) , Jean-François Bureau (3) , Alexandre Pawlik (1) , Valérie Michel (4) , Gregory G. Jouvion (5, 6) , Michel Huerre (6, 7) , Marco Severgnini (8) , C. Consolandi (8) , Clelia Peano (8) , Roland Brosch (1) , Eliette Touati (4) , Claude Leclerc (2)

1 Pathogénomique mycobactérienne intégrée
2 Régulation Immunitaire et Vaccinologie
3 Génétique fonctionnelle des Maladies infectieuses - Functional Genetics of Infectious Diseases
4 Pathogenèse de Helicobacter
5 Histopathologie humaine et Modèles animaux
6 Histotechnologie et Pathologie
7 Institut Curie [Paris]
8 ITB - Istituto di Tecnologie Biomediche [Segrate]

Epidemiological and experimental observations suggest that chronic microbial colonization can impact the immune control of other unrelated pathogens contracted in a concomitant or sequential manner. Possible interactions between Mycobacterium tuberculosis infection and persistence of other bacteria have scarcely been investigated. Here we demonstrated that natural colonization of the digestive tract with Helicobacter hepaticus in mice is concomitant with modification of the gut microbiota, subclinical inflammation, and drastic impairment of immune control of the growth of subsequently administered M. tuberculosis, which results in severe lung tissue injury. Our results provided insights upon the fact that this prior H. hepaticus colonization leads to failures in the mechanisms that could prevent the otherwise balanced cross-talk between M. tuberculosis and the immune system. Such disequilibrium ultimately leads to the inhibition of control of mycobacterial growth, outbreak of inflammation, and lung pathology. Among the dysregulated immune signatures, we noticed a correlation between the detrimental lung injury and the accumulation of activated T-lymphocytes. Our findings suggest that the impact of prior Helicobacter spp. colonization and subsequent M. tuberculosis parasitism might be greater than previously thought, which is a key point given that both species are among the most frequent invasive bacteria in human populations.

Domaines: Immunité adaptative; Immunité innée; Bactériologie

Laleh Majlessi, Fadel Sayes, Jean-François Bureau, Alexandre Pawlik, Valérie Michel, et al.. Colonization with Helicobacter is concomitant with modified gut microbiota and drastic failure of the immune control of Mycobacterium tuberculosis. Mucosal Immunology, 2017, 10 (5), pp.1178 - 1189. ⟨10.1038/mi.2016.140⟩. ⟨hal-01652031⟩