Mycobacterium tuberculosis evades host immunity by recruiting mesenchymal stem cells.
Tuberculosis (TB) is the cause of 2 million deaths each year, which is the second highest cause of mortality from a single infectious disease worldwide. Resistance of these organisms to drugs has emerged as an important health concern. Alternative approaches to the prevention and treatment of tuberculosis are therefore urgently needed. Despite the generation of robust host immune responses, Mycobacterium tuberculosis (M. tb) successfully evades host immunity and establishes a persistent infection. The mechanism(s) by which M. tuberculosis manages to persist in the face of potent host immune responses remain(s) incompletely understood. Here, we demonstrate that M. tb suppresses T-lymphocyte responses by recruiting mesenchymal stem cells (MSCs) to the site of infection. We found that MSCs infiltrated tissues in mice containing M. tb organisms and T lymphocytes. We further demonstrate that MSCs suppressed T-cell responses by producing nitric oxide. Our findings reveal a key role of MSCs in the capacity of M. tb to evade host immune responses and identify these cells as unique targets for therapeutic intervention in tuberculosis.
Immunology Group, International Center for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India.
Shilpa
S
Raghuvanshi
Pawan
P
Sharma
Sarman
S
Singh
Luc
L
Van Kaer
Gobardhan
G
Das
D000328:Adult; D000818:Animals; D016207:Cytokines / Q000276:immunology; D005260:Female; D006099:Granuloma / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D006801:Humans; D007107:Immune System / Q000502:physiology*; D007165:Immunosuppression Therapy; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D009569:Nitric Oxide / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology
D016207:Cytokines; D009569:Nitric Oxide