The Role of KLRG1 in Human CD4+ T-Cell Immunity Against Tuberculosis.
J Infect Dis
; 217(9): 1491-1503, 2018 04 11.
Article
em En
| MEDLINE
| ID: mdl-29373700
ABSTRACT
Background:
KLRG1 is a marker of terminally differentiated CD8+ T cells in viral infection, but its role in human Mycobacterium tuberculosis infection remains elusive.Methods:
A set of cohorts of patients with tuberculosis was designed, and the expression profiles and functions of KLRG1+CD4+ T cells were determined with and without antibody blocking.Results:
KLRG1 expression on CD4+ T cells was significantly increased in patients with active tuberculosis, compared with healthy controls and patients without tuberculosis. Upon M. tuberculosis-specific stimulation, the ability to secrete interferon γ, interleukin 2, and tumor necrosis factor α was significantly greater in KLRG1-expressing CD4+ T cells than in their KLRG-negative counterparts and was accompanied by a decreased proportion of regulatory T cells and increased Akt signaling. However, KLRG1-expressing CD4+ T cells had a shorter life-span, which was associated with a higher apoptosis rate but a similar proliferative response. Blockade of KLRG1 signaling significantly enhanced interferon γ and interleukin 2 secretion without affecting either cell apoptosis or multiplication. Addition of a specific Akt inhibitor prevented this increased cytokine response, implicating the Akt signaling pathway.Conclusions:
Our study delineated the profile of KLRG1+CD4+ T cells in patients with tuberculosis and suggests that M. tuberculosis infection drives CD4+ T cells to acquire increased effector function in a terminally differentiated state, which is restrained by KLRG1 via KLRG1/Akt signaling pathway.
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Base de dados:
MEDLINE
Assunto principal:
Tuberculose
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Linfócitos T CD4-Positivos
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Transativadores
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Regulação da Expressão Gênica
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Lectinas Tipo C
Tipo de estudo:
Observational_studies
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Risk_factors_studies
Limite:
Adolescent
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Adult
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Aged
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Aged80
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Child
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Child, preschool
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article