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Bacterial clearance reverses a skewed T-cell repertoire induced by Salmonella infection.

ABSTRACT: Salmonella typhimurium invades the spleen, liver, and peripheral lymph nodes and has recently been detected in the bone marrow and thymus, resulting in a reduced thymic size and a decline in the total number of thymic cells. A specific deletion of the double-positive cell subset has been characterized, yet the export of mature T cells to the periphery remains normal. We analyzed Salmonella pathogenesis regarding thymic structure and the T-cell maturation process. We demonstrate that, despite alterations in the thymic structure, T-cell development is maintained during Salmonella infection, allowing the selection of single-positive T-cell clones expressing particular T-cell receptor beta chains (TCR-V?). Moreover, the treatment of infected mice with an antibiotic restored the normal thymic architecture and thymocyte subset distribution. Additionally, the frequency of TCR-V? usage after treatment was comparable to that in non-infected mice. However, bacteria were still recovered from the thymus after 1 month of treatment. Our data reveal that a skewed T-cell developmental process is present in the Salmonella-infected thymus that alters the TCR-V? usage frequency. Likewise, the post-treatment persistence of Salmonella reveals a novel function of the thymus as a potential reservoir for this infectious agent.

SUBMITTER: Leyva-Rangel JP

PROVIDER: S-EPMC4578521 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Bacterial clearance reverses a skewed T-cell repertoire induced by Salmonella infection.

Leyva-Rangel Jessica P JP de Los Angeles Hernández-Cueto Maria M Galan-Enriquez Carlos-Samuel CS López-Medina Marcela M Ortiz-Navarrete Vianney V

Immunity, inflammation and disease 20150506 3

Salmonella typhimurium invades the spleen, liver, and peripheral lymph nodes and has recently been detected in the bone marrow and thymus, resulting in a reduced thymic size and a decline in the total number of thymic cells. A specific deletion of the double-positive cell subset has been characterized, yet the export of mature T cells to the periphery remains normal. We analyzed Salmonella pathogenesis regarding thymic structure and the T-cell maturation process. We demonstrate that, despite alt ...[more]

PMID: 26417438

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Dataset Information

Bacterial clearance reverses a skewed T-cell repertoire induced by Salmonella infection.

Publications

Bacterial clearance reverses a skewed T-cell repertoire induced by Salmonella infection.

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