TY - JOUR A1 - Lagler, Charlotte A1 - El-Mesery, Mohamed A1 - Kübler, Alexander Christian A1 - Müller-Richter, Urs Dietmar Achim A1 - Stühmer, Thorsten A1 - Nickel, Joachim A1 - Müller, Thomas Dieter A1 - Wajant, Harald A1 - Seher, Axel T1 - The anti-myeloma activity of bone morphogenetic protein 2 predominantly relies on the induction of growth arrest and is apoptosis-independent JF - PLoS ONE N2 - Multiple myeloma (MM), a malignancy of the bone marrow, is characterized by a pathological increase in antibody-producing plasma cells and an increase in immunoglobulins (plasmacytosis). In recent years, bone morphogenetic proteins (BMPs) have been reported to be activators of apoptotic cell death in neoplastic B cells in MM. Here, we use bone morphogenetic protein 2 (BMP2) to show that the "apoptotic" effect of BMPs on human neoplastic B cells is dominated by anti-proliferative activities and cell cycle arrest and is apoptosis-independent. The anti-proliferative effect of BMP2 was analysed in the human cell lines KMS12-BM and L363 using WST-1 and a Coulter counter and was confirmed using CytoTox assays with established inhibitors of programmed cell death (zVAD-fmk and necrostatin-1). Furthermore, apoptotic activity was compared in both cell lines employing western blot analysis for caspase 3 and 8 in cells treated with BMP2 and FasL. Additionally, expression profiles of marker genes of different cell death pathways were analysed in both cell lines after stimulation with BMP2 for 48h using an RT-PCR-based array. In our experiments we observed that there was rather no reduction in absolute cell number, but cells stopped proliferating following treatment with BMP2 instead. The time frame (48–72 h) after BMP2 treatment at which a reduction in cell number is detectable is too long to indicate a directly BMP2-triggered apoptosis. Moreover, in comparison to robust apoptosis induced by the approved apoptotic factor FasL, BMP2 only marginally induced cell death. Consistently, neither the known inhibitor of apoptotic cell death zVAD-fmk nor the necroptosis inhibitor necrostatin-1 was able to rescue myeloma cell growth in the presence of BMP2. KW - apoptosis KW - gene expression KW - necrotic cell death KW - multiple myeloma KW - cell metabolism KW - cell cycle and cell division KW - B cells Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158993 VL - 12 IS - 10 ER - 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 -