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Regulatory T cell ablation causes acute T cell lymphopenia.

ABSTRACT: Regulatory T (Treg) cells enforce T cell homeostasis and maintain peripheral T cell tolerance. Here we report a previously unappreciated phenomenon of acute T cell lymphopenia in secondary lymphoid organs and non-lymphoid tissues triggered by Treg cell depletion that precedes the expansion of self-reactive T cells. Lymphopenia affects both neonates and adults indicating a dominant role of Treg cells in maintaining peripheral T cell numbers regardless of the developmental stage. The lymphopenia was neither triggered by caspase-dependent apoptosis nor macrophage-mediated clearance of T cells, nor diminished survival of naïve or recently activated T cells due to paucity of IL-7. It is possible that transient lymphopenia associated with congenital or acute Treg cell deficiency may contribute to the development of T cell mediated autoimmune disorders.

SUBMITTER: Moltedo B

PROVIDER: S-EPMC3900634 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Regulatory T cell ablation causes acute T cell lymphopenia.

Moltedo Bruno B Hemmers Saskia S Rudensky Alexander Y AY

PloS one 20140123 1

Regulatory T (Treg) cells enforce T cell homeostasis and maintain peripheral T cell tolerance. Here we report a previously unappreciated phenomenon of acute T cell lymphopenia in secondary lymphoid organs and non-lymphoid tissues triggered by Treg cell depletion that precedes the expansion of self-reactive T cells. Lymphopenia affects both neonates and adults indicating a dominant role of Treg cells in maintaining peripheral T cell numbers regardless of the developmental stage. The lymphopenia w ...[more]

PMID: 24466225

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