TY - JOUR A1 - Wong, David A1 - Winter, Oliver A1 - Hartig, Christina A1 - Siebels, Svenja A1 - Szyska, Martin A1 - Tiburzy, Benjamin A1 - Meng, Lingzhang A1 - Kulkarni, Upasana A1 - Fähnrich, Anke A1 - Bommert, Kurt A1 - Bargou, Ralf A1 - Berek, Claudia A1 - Van, Trung Chu A1 - Bogen, Bjarne A1 - Jundt, Franziska A1 - Manz, Rudolf Armin T1 - Eosinophils and Megakaryocytes Support the Early Growth of Murine MOPC315 Myeloma Cells in Their Bone Marrow Niches JF - PLOS ONE N2 - Multiple myeloma is a bone marrow plasma cell tumor which is supported by the external growth factors APRIL and IL-6, among others. Recently, we identified eosinophils and megakaryocytes to be functional components of the micro-environmental niches of benign bone marrow plasma cells and to be important local sources of these cytokines. Here, we investigated whether eosinophils and megakaryocytes also support the growth of tumor plasma cells in the MOPC315. BM model for multiple myeloma. As it was shown for benign plasma cells and multiple myeloma cells, IL-6 and APRIL also supported MOPC315. BM cell growth in vitro, IL-5 had no effect. Depletion of eosinophils in vivo by IL-5 blockade led to a reduction of the early myeloma load. Consistent with this, myeloma growth in early stages was retarded in eosinophil-deficient Delta dblGATA-1 mice. Late myeloma stages were unaffected, possibly due to megakaryocytes compensating for the loss of eosinophils, since megakaryocytes were found to be in contact with myeloma cells in vivo and supported myeloma growth in vitro. We conclude that eosinophils and megakaryocytes in the niches for benign bone marrow plasma cells support the growth of malignant plasma cells. Further investigations are required to test whether perturbation of these niches represents a potential strategy for the treatment of multiple myeloma. KW - plasma cells KW - human multiple-myeloma KW - immune response KW - receptor expression KW - B-cells KW - stromal cells KW - dexamethasone KW - april KW - survival KW - Interleukin-5 Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115269 VL - 9 IS - 10 ER -