TY  - JOUR
A1  - Schmid, Tobias
A1  - Falter, Lena
A1  - Weber, Sabine
A1  - Müller, Nils
A1  - Molitor, Konstantin
A1  - Zeller, David
A1  - Weber-Steffens, Dorothea
A1  - Hehlgans, Thomas
A1  - Wajant, Harald
A1  - Mostböck, Sven
A1  - Männel, Daniela N.
T1  - Chronic inflammation increases the sensitivity of mouse Treg for TNFR2 costimulation
JF  - Frontiers in Immunology
N2  - TNF receptor type 2 (TNFR2) has gained attention as a costimulatory receptor for T cells and as critical factor for the development of regulatory T cells (Treg) and myeloid suppressor cells. Using the TNFR2-specific agonist TNCscTNF80, direct effects of TNFR2 activation on myeloid cells and T cells were investigated in mice. \(In\) \(vitro\), TNCscTNF80 induced T cell proliferation in a costimulatory fashion, and also supported \(in\) \(vitro\) expansion of Treg cells. In addition, activation of TNFR2 retarded differentiation of bone marrow-derived immature myeloid cells in culture and reduced their suppressor function. \(In\) \(vivo\) application of TNCscTNF80-induced mild myelopoiesis in naïve mice without affecting the immune cell composition. Already a single application expanded Treg cells and improved suppression of CD4 T cells in mice with chronic inflammation. By contrast, multiple applications of the TNFR2 agonist were required to expand Treg cells in naïve mice. Improved suppression of T cell proliferation depended on expression of TNFR2 by T cells in mice repeatedly treated with TNCscTNF80, without a major contribution of TNFR2 on myeloid cells. Thus, TNFR2 activation on T cells in naïve mice can lead to immune suppression \(in\) \(vivo\). These findings support the important role of TNFR2 for Treg cells in immune regulation.
KW  - molecular medicine
KW  - inflammation
KW  - immune regulation
KW  - costimulation
KW  - MDSC
KW  - TNFR2
KW  - regulatory T cell
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-173259
VL  - 8
ER  - 
TY  - JOUR
A1  - Alb, Miriam
A1  - Sie, Christopher
A1  - Adam, Christian
A1  - Chen, Suzie
A1  - Becker, Jürgen C.
A1  - Schrama, David
T1  - Cellular and cytokine-dependent immunosuppressive mechanisms of grm1-transgenic murine melanoma
JF  - Cancer Immunology, Immunotherapy
N2  - Grm1-transgenic mice spontaneously develop cutaneous melanoma. This model allowed us to scrutinize the generic immune responses over the course of melanoma development. To this end, lymphocytes obtained from spleens, unrelated lymph nodes and tumor-draining lymph nodes of mice with no evidence of disease, and low or high tumor burden were analyzed ex vivo and in vitro. Thereby, we could demonstrate an increase in the number of activated CD4\(^+\) and CD8+ lymphocytes in the respective organs with increasing tumor burden. However, mainly CD4\(^+\) T cells, which could constitute both T helper as well as immunosuppressive regulatory T cells, but not CD8\(^+\) T cells, expressed activation markers upon in vitro stimulation when obtained from tumor-bearing mice. Interestingly, these cells from tumor-burdened animals were also functionally hampered in their proliferative response even when subjected to strong in vitro stimulation. Further analyses revealed that the increased frequency of regulatory T cells in tumor-bearing mice is an early event present in all lymphoid organs. Additionally, expression of the immunosuppressive cytokines TGF-β1 and IL-10 became more evident with increased tumor burden. Notably, TGF-β1 is strongly expressed in both the tumor and the tumor-draining lymph node, whereas IL-10 expression is more pronounced in the lymph node, suggesting a more complex regulation of IL-10. Thus, similar to the situation in melanoma patients, both cytokines as well as cellular immune escape mechanisms seem to contribute to the observed immunosuppressed state of tumor-bearing grm1-transgenic mice, suggesting that this model is suitable for preclinical testing of immunomodulatory therapeutics.
KW  - regulatory T cell
KW  - melanoma
KW  - immune suppression
KW  - tumor-draining lymph node
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125096
VL  - 61
IS  - 12
ER  -