CD25+Foxp3+ Regulatory T Cells Facilitate CD4+ T Cell Clonal Anergy Induction during the Recovery from Lymphopenia

Department of Medicine, Center for Immunology, University of Minnesota Medical School, 312 Church Street SE, Minneapolis, MN 55455, USA.
The Journal of Immunology (Impact Factor: 4.92). 06/2006; 176(10):5880-9. DOI: 10.4049/jimmunol.176.10.5880
Source: PubMed


T cell clonal anergy induction in lymphopenic nu/nu mice was found to be ineffective. Exposure to a tolerizing peptide Ag regimen instead induced aggressive CD4(+) cell cycle progression and increased Ag responsiveness (priming). Reconstitution of T cell-deficient mice by an adoptive transfer of mature peripheral lymphocytes was accompanied by the development of a CD25(+)Foxp3(+)CTLA-4(+)CD4(+) regulatory T cell population that acted to dampen Ag-driven cell cycle progression and facilitate the induction of clonal anergy in nearby responder CD25(-)CD4(+) T cells. Thus, an early recovery of CD25(+) regulatory T cells following a lymphopenic event can prevent exuberant Ag-stimulated CD4(+) cell cycle progression and promote the development of clonal anergy.

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