@article{ChopraBiehlSteinfattetal.2016,
  author    = {Chopra, Martin and Biehl, Marlene and Steinfatt, Tim and Brandl, Andreas and Kums, Juliane and Amich, Jorge and Vaeth, Martin and Kuen, Janina and Holtappels, Rafaela and Podlech, J{\"u}rgen and Mottok, Anja and Kraus, Sabrina and Jord{\´a}n-Garotte, Ana-Laura and B{\"a}uerlein, Carina A. and Brede, Christian and Ribechini, Eliana and Fick, Andrea and Seher, Axel and Polz, Johannes and Ottmueller, Katja J. and Baker, Jeannette and Nishikii, Hidekazu and Ritz, Miriam and Mattenheimer, Katharina and Schwinn, Stefanie and Winter, Thorsten and Sch{\"a}fer, Viktoria and Krappmann, Sven and Einsele, Hermann and M{\"u}ller, Thomas D. and Reddehase, Matthias J. and Lutz, Manfred B. and M{\"a}nnel, Daniela N. and Berberich-Siebelt, Friederike and Wajant, Harald and Beilhack, Andreas},
  title     = {Exogenous TNFR2 activation protects from acute GvHD via host T reg cell expansion},
  series = {Journal of Experimental Medicine},
  volume    = {213},
  journal   = {Journal of Experimental Medicine},
  number    = {9},
  doi       = {10.1084/jem.20151563},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-187640},
  pages     = {1881-1900},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{KlammertMuellerHellmannetal.2015,
  author    = {Klammert, Uwe and M{\"u}ller, Thomas D. and Hellmann, Tina V. and Wuerzler, Kristian K. and Kotzsch, Alexander and Schliermann, Anna and Schmitz, Werner and Kuebler, Alexander C. and Sebald, Walter and Nickel, Joachim},
  title     = {GDF-5 can act as a context-dependent BMP-2 antagonist},
  series = {BMC Biology},
  volume    = {13},
  journal   = {BMC Biology},
  number    = {77},
  doi       = {10.1186/s12915-015-0183-8},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125550},
  year      = {2015},
  abstract  = {Background Bone morphogenetic protein (BMP)-2 and growth and differentiation factor (GDF)-5 are two related transforming growth factor (TGF)-β family members with important functions in embryonic development and tissue homeostasis. BMP-2 is best known for its osteoinductive properties whereas GDF-5—as evident from its alternative name, cartilage derived morphogenetic protein 1—plays an important role in the formation of cartilage. In spite of these differences both factors signal by binding to the same subset of BMP receptors, raising the question how these different functionalities are generated. The largest difference in receptor binding is observed in the interaction with the type I receptor BMPR-IA. GDF-5, in contrast to BMP-2, shows preferential binding to the isoform BMPR-IB, which is abrogated by a single amino acid (A57R) substitution. The resulting variant, GDF-5 R57A, represents a "BMP-2 mimic" with respect to BMP receptor binding. In this study we thus wanted to analyze whether the two growth factors can induce distinct signals via an identically composed receptor. Results Unexpectedly and dependent on the cellular context, GDF-5 R57A showed clear differences in its activity compared to BMP-2. In ATDC-5 cells, both ligands induced alkaline phosphatase (ALP) expression with similar potency. But in C2C12 cells, the BMP-2 mimic GDF-5 R57A (and also wild-type GDF-5) clearly antagonized BMP-2-mediated ALP expression, despite signaling in both cell lines occurring solely via BMPR-IA. The BMP-2- antagonizing properties of GDF-5 and GDF-5 R57A could also be observed in vivo when implanting BMP-2 and either one of the two GDF-5 ligands simultaneously at heterotopic sites. Conclusions Although comparison of the crystal structures of the GDF-5 R57A:BMPR-IAEC- and BMP-2:BMPR-IAEC complex revealed small ligand-specific differences, these cannot account for the different signaling characteristics because the complexes seem identical in both differently reacting cell lines. We thus predict an additional component, most likely a not yet identified GDF-5-specific co-receptor, which alters the output of the signaling complexes. Hence the presence or absence of this component then switches GDF-5′s signaling capabilities to act either similar to BMP-2 or as a BMP-2 antagonist. These findings might shed new light on the role of GDF-5, e.g., in cartilage maintenance and/or limb development in that it might act as an inhibitor of signaling events initiated by other BMPs.},
  language  = {en}
}
@article{vanDintherZhangWeidaueretal.2013,
  author    = {van Dinther, Maarten and Zhang, Juan and Weidauer, Stella E. and Boschert, Verena and Muth, Eva-Maria and Knappik, Achim and de Gorter, David J. J. and van Kasteren, Puck B. and Frisch, Christian and M{\"u}ller, Thomas D. and ten Dijke, Peter},
  title     = {Anti-Sclerostin Antibody Inhibits Internalization of Sclerostin and Sclerostin-Mediated Antagonism of Wnt/LRP6 Signaling},
  series = {PLoS ONE},
  volume    = {8},
  journal   = {PLoS ONE},
  number    = {4},
  doi       = {10.1371/journal.pone.0062295},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130981},
  pages     = {e62295},
  year      = {2013},
  abstract  = {Sclerosteosis is a rare high bone mass disease that is caused by inactivating mutations in the SOST gene. Its gene product, Sclerostin, is a key negative regulator of bone formation and might therefore serve as a target for the anabolic treatment of osteoporosis. The exact molecular mechanism by which Sclerostin exerts its antagonistic effects on Wnt signaling in bone forming osteoblasts remains unclear. Here we show that Wnt3a-induced transcriptional responses and induction of alkaline phosphatase activity, an early marker of osteoblast differentiation, require the Wnt co-receptors LRP5 and LRP6. Unlike Dickkopf1 (DKK1), Sclerostin does not inhibit Wnt-3a-induced phosphorylation of LRP5 at serine 1503 or LRP6 at serine 1490. Affinity labeling of cell surface proteins with \([^{125} I]\) Sclerostin identified LRP6 as the main specific Sclerostin receptor in multiple mesenchymal cell lines. When cells were challenged with Sclerostin fused to recombinant green fluorescent protein (GFP) this was internalized, likely via a Clathrin-dependent process, and subsequently degraded in a temperature and proteasome-dependent manner. Ectopic expression of LRP6 greatly enhanced binding and cellular uptake of Sclerostin-GFP, which was reduced by the addition of an excess of non-GFP-fused Sclerostin. Finally, an anti-Sclerostin antibody inhibited the internalization of Sclerostin-GFP and binding of Sclerostin to LRP6. Moreover, this antibody attenuated the antagonistic activity of Sclerostin on canonical Wnt-induced responses.},
  language  = {en}
}