| Autor: |
Van Belle, Tom L., Dooms, Hans, Boonefaes, Tom, Xiao-Qing Wei, Leclercq, Georges, Grooten, Johan, Freitas, Antonio A. |
| Předmět: |
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| Zdroj: |
PLoS ONE; Sep2012, Vol. 7 Issue 9, Special section p1-11, 11p |
| Abstrakt: |
Due to its critical role in NK cell differentiation and CD8+T cell homeostasis, the importance of IL-15 is more firmly established for cytolytic effectors of the immune system than for CD4+T cells. The increased levels of IL-15 found in several CD4 T cell-driven (auto-) immune diseases prompted us to examine how IL-15 influences murine CD4+T cell responses to low dose TCR-stimulation in vitro. We show that IL-15 exerts growth factor activity on both CD4+ and CD8+T cells in a TCR-dependent and Cyclosporin A-sensitive manner. In CD4+T cells, IL-15 augmented initial IL-2-dependent expansion and once IL-15Rα was upregulated, IL-15 sustained the TCR-induced expression of IL-2/15Rβ, supporting proliferation independently of secreted IL-2. Moreover, IL-15 counteracts CD4+T cell suppression by a gradually expanding CD25HighCD4+T cell subset that expresses Foxp3 and originates from CD4+ CD25+ Tregs. These in vitro data suggest that IL-15 may dramatically strengthen the T cell response to suboptimal TCR-triggering by overcoming an activation threshold set by Treg that might create a risk for autoimmune pathology. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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