Differential control of immune cell homeostasis by Foxp3+regulatory T cells in murine peripheral lymph nodes and spleen

摘要

Foxp3⁺ regulatory T cells (Tregs) hamper efficient immune responses to tumors and chronic infections. Therefore, depletion of Foxp3⁺ Tregs has been proposed as therapeutic option to boost immune responses and to improve vaccinations. Although Treg-mediated control of T cell homeostasis is well established, Foxp3⁺ Treg interaction with other immune cell subsets is only incompletely understood. Thus, the present study aimed at examining dynamic effects of experimental Foxp3⁺ Treg depletion on a broad range of immune cell subsets, including B cells, natural killer cells, and myeloid cells. Striking differences were observed when peripheral lymph nodes (LN) and spleen were compared. B cells, for example, showed a massive and long-lasting accumulation only in LN but not in spleen of transiently Treg-depleted mice. In contrast, monocyte-derived dendritic cells, which are potent inducers of T cell responses, also accumulated selectively, but only transiently in LN, suggesting that this cell population is under very strict control of Foxp3⁺ Tregs. In summary, the observations described here provide insights into the dynamics of immune cells after selective depletion of Foxp3⁺ Tregs. This will allow a better prediction of the impactof Treg ablation in translational studies that aim at boosting immune responsesand vaccinations.