TY - JOUR A1 - Chopra, Martin A1 - Biehl, Marlene A1 - Steinfatt, Tim A1 - Brandl, Andreas A1 - Kums, Juliane A1 - Amich, Jorge A1 - Vaeth, Martin A1 - Kuen, Janina A1 - Holtappels, Rafaela A1 - Podlech, Jürgen A1 - Mottok, Anja A1 - Kraus, Sabrina A1 - Jordán-Garotte, Ana-Laura A1 - Bäuerlein, Carina A. A1 - Brede, Christian A1 - Ribechini, Eliana A1 - Fick, Andrea A1 - Seher, Axel A1 - Polz, Johannes A1 - Ottmueller, Katja J. A1 - Baker, Jeannette A1 - Nishikii, Hidekazu A1 - Ritz, Miriam A1 - Mattenheimer, Katharina A1 - Schwinn, Stefanie A1 - Winter, Thorsten A1 - Schäfer, Viktoria A1 - Krappmann, Sven A1 - Einsele, Hermann A1 - Müller, Thomas D. A1 - Reddehase, Matthias J. A1 - Lutz, Manfred B. A1 - Männel, Daniela N. A1 - Berberich-Siebelt, Friederike A1 - Wajant, Harald A1 - Beilhack, Andreas T1 - Exogenous TNFR2 activation protects from acute GvHD via host T reg cell expansion JF - Journal of Experimental Medicine N2 - Donor CD4\(^+\)Foxp3\(^+\) regulatory T cells (T reg cells) suppress graft-versus-host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (HCT allo-HCT]). Current clinical study protocols rely on the ex vivo expansion of donor T reg cells and their infusion in high numbers. In this study, we present a novel strategy for inhibiting GvHD that is based on the in vivo expansion of recipient T reg cells before allo-HCT, exploiting the crucial role of tumor necrosis factor receptor 2 (TNFR2) in T reg cell biology. Expanding radiation-resistant host T reg cells in recipient mice using a mouse TNFR2-selective agonist before allo-HCT significantly prolonged survival and reduced GvHD severity in a TNFR2-and T reg cell-dependent manner. The beneficial effects of transplanted T cells against leukemia cells and infectious pathogens remained unaffected. A corresponding human TNFR2-specific agonist expanded human T reg cells in vitro. These observations indicate the potential of our strategy to protect allo-HCT patients from acute GvHD by expanding T reg cells via selective TNFR2 activation in vivo. KW - Tumor-necrosis-factor KW - Regulatory-cells KW - Bone marrow transplantantation KW - Graft-versus-leukemia KW - Rheumatoid arthritis KW - Autoimmune diseases KW - Factor receptor KW - Alpha therapy KW - Expression KW - Suppression Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187640 VL - 213 IS - 9 ER - TY - JOUR A1 - Dahlhoff, Julia A1 - Manz, Hannah A1 - Steinfatt, Tim A1 - Delgado-Tascon, Julia A1 - Seebacher, Elena A1 - Schneider, Theresa A1 - Wilnit, Amy A1 - Mokhtari, Zeinab A1 - Tabares, Paula A1 - Böckle, David A1 - Rasche, Leo A1 - Martin Kortüm, K. A1 - Lutz, Manfred B. A1 - Einsele, Hermann A1 - Brandl, Andreas A1 - Beilhack, Andreas T1 - Transient regulatory T-cell targeting triggers immune control of multiple myeloma and prevents disease progression JF - Leukemia N2 - Multiple myeloma remains a largely incurable disease of clonally expanding malignant plasma cells. The bone marrow microenvironment harbors treatment-resistant myeloma cells, which eventually lead to disease relapse in patients. In the bone marrow, CD4\(^{+}\)FoxP3\(^{+}\) regulatory T cells (Tregs) are highly abundant amongst CD4\(^{+}\) T cells providing an immune protective niche for different long-living cell populations, e.g., hematopoietic stem cells. Here, we addressed the functional role of Tregs in multiple myeloma dissemination to bone marrow compartments and disease progression. To investigate the immune regulation of multiple myeloma, we utilized syngeneic immunocompetent murine multiple myeloma models in two different genetic backgrounds. Analyzing the spatial immune architecture of multiple myeloma revealed that the bone marrow Tregs accumulated in the vicinity of malignant plasma cells and displayed an activated phenotype. In vivo Treg depletion prevented multiple myeloma dissemination in both models. Importantly, short-term in vivo depletion of Tregs in mice with established multiple myeloma evoked a potent CD8 T cell- and NK cell-mediated immune response resulting in complete and stable remission. Conclusively, this preclinical in-vivo study suggests that Tregs are an attractive target for the treatment of multiple myeloma. KW - Multiple myeloma KW - transient regulatory T-cell targeting KW - immune control Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-271787 SN - 1476-5551 VL - 36 IS - 3 ER - TY - JOUR A1 - Weißbach, Susann A1 - Heredia-Guerrero, Sofia Catalina A1 - Barnsteiner, Stefanie A1 - Großhans, Lukas A1 - Bodem, Jochen A1 - Starz, Hanna A1 - Langer, Christian A1 - Appenzeller, Silke A1 - Knop, Stefan A1 - Steinbrunn, Torsten A1 - Rost, Simone A1 - Einsele, Hermann A1 - Bargou, Ralf Christian A1 - Rosenwald, Andreas A1 - Stühmer, Thorsten A1 - Leich, Ellen T1 - Exon-4 Mutations in KRAS Affect MEK/ERK and PI3K/AKT Signaling in Human Multiple Myeloma Cell Lines JF - Cancers N2 - Approximately 20% of multiple myeloma (MM) cases harbor a point mutation in KRAS. However, there is still no final consent on whether KRAS-mutations are associated with disease outcome. Specifically, no data exist on whether KRAS-mutations have an impact on survival of MM patients at diagnosis in the era of novel agents. Direct blockade of KRAS for therapeutic purposes is mostly impossible, but recently a mutation-specific covalent inhibitor targeting KRAS\(^{p.G12C}\) entered into clinical trials. However, other KRAS hotspot-mutations exist in MM patients, including the less common exon-4 mutations. For the current study, the coding regions of KRAS were deep-sequenced in 80 newly diagnosed MM patients, uniformely treated with three cycles of bortezomib plus dexamethasone and cyclophosphamide (VCD)-induction, followed by high-dose chemotherapy and autologous stem cell transplantation. Moreover, the functional impact of KRAS\(^{p.G12A}\) and the exon-4 mutations p.A146T and p.A146V on different survival pathways was investigated. Specifically, KRAS\(^{WT}\), KRAS\(^{p.G12A}\), KRAS\(^{p.A146T}\), and KRAS\(^{p.A146V}\) were overexpressed in HEK293 cells and the KRAS\(^{WT}\) MM cell lines JJN3 and OPM2 using lentiviral transduction and the Sleeping Beauty vector system. Even though KRAS-mutations were not correlated with survival, all KRAS-mutants were found capable of potentially activating MEK/ERK- and sustaining PI3K/AKT-signaling in MM cells. KW - multiple myeloma KW - KRAS KW - MEK/ERK-signaling KW - AKT-signaling KW - amplicon sequencing Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200617 SN - 2072-6694 VL - 12 IS - 2 ER -