@article{SchwinnMokhtariThuseketal.2021, author = {Schwinn, Stefanie and Mokhtari, Zeinab and Thusek, Sina and Schneider, Theresa and Sir{\´e}n, Anna-Leena and Tiemeyer, Nicola and Caruana, Ignazio and Miele, Evelina and Schlegel, Paul G. and Beilhack, Andreas and W{\"o}lfl, Matthias}, title = {Cytotoxic effects and tolerability of gemcitabine and axitinib in a xenograft model for c-myc amplified medulloblastoma}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, number = {1}, doi = {10.1038/s41598-021-93586-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261476}, year = {2021}, abstract = {Medulloblastoma is the most common high-grade brain tumor in childhood. Medulloblastomas with c-myc amplification, classified as group 3, are the most aggressive among the four disease subtypes resulting in a 5-year overall survival of just above 50\%. Despite current intensive therapy regimens, patients suffering from group 3 medulloblastoma urgently require new therapeutic options. Using a recently established c-myc amplified human medulloblastoma cell line, we performed an in-vitro-drug screen with single and combinatorial drugs that are either already clinically approved or agents in the advanced stage of clinical development. Candidate drugs were identified in vitro and then evaluated in vivo. Tumor growth was closely monitored by BLI. Vessel development was assessed by 3D light-sheet-fluorescence-microscopy. We identified the combination of gemcitabine and axitinib to be highly cytotoxic, requiring only low picomolar concentrations when used in combination. In the orthotopic model, gemcitabine and axitinib showed efficacy in terms of tumor control and survival. In both models, gemcitabine and axitinib were better tolerated than the standard regimen comprising of cisplatin and etoposide phosphate. 3D light-sheet-fluorescence-microscopy of intact tumors revealed thinning and rarefication of tumor vessels, providing one explanation for reduced tumor growth. Thus, the combination of the two drugs gemcitabine and axitinib has favorable effects on preventing tumor progression in an orthotopic group 3 medulloblastoma xenograft model while exhibiting a favorable toxicity profile. The combination merits further exploration as a new approach to treat high-risk group 3 medulloblastoma.}, language = {en} } @article{ShaikhVargasMokhtarietal.2021, author = {Shaikh, Haroon and Vargas, Juan Gamboa and Mokhtari, Zeinab and Jarick, Katja J. and Ulbrich, Maria and Mosca, Josefina Pe{\~n}a and Viera, Estibaliz Arellano and Graf, Caroline and Le, Duc-Dung and Heinze, Katrin G. and B{\"u}ttner-Herold, Maike and Rosenwald, Andreas and Pezoldt, Joern and Huehn, Jochen and Beilhack, Andreas}, title = {Mesenteric Lymph Node Transplantation in Mice to Study Immune Responses of the Gastrointestinal Tract}, series = {Frontiers in Immunology}, volume = {12}, journal = {Frontiers in Immunology}, issn = {1664-3224}, doi = {10.3389/fimmu.2021.689896}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-244869}, year = {2021}, abstract = {Mesenteric lymph nodes (mLNs) are sentinel sites of enteral immunosurveillance and immune homeostasis. Immune cells from the gastrointestinal tract (GIT) are constantly recruited to the mLNs in steady-state and under inflammatory conditions resulting in the induction of tolerance and immune cells activation, respectively. Surgical dissection and transplantation of lymph nodes (LN) is a technique that has supported seminal work to study LN function and is useful to investigate resident stromal and endothelial cell biology and their cellular interactions in experimental disease models. Here, we provide a detailed protocol of syngeneic mLN transplantation and report assays to analyze effective mLN engraftment in congenic recipients. Transplanted mLNs allow to study T cell activation and proliferation in preclinical mouse models. Donor mLNs proved viable and functional after surgical transplantation and regenerated blood and lymphatic vessels. Immune cells from the host completely colonized the transplanted mLNs within 7-8 weeks after the surgical intervention. After allogeneic hematopoietic cell transplantation (allo-HCT), adoptively transferred allogeneic CD4+ T cells from FVB/N (H-2q) mice homed to the transplanted mLNs in C57BL/6 (H-2b) recipients during the initiation phase of acute graft-versus-host disease (aGvHD). These CD4+ T cells retained full proliferative capacity and upregulated effector and gut homing molecules comparable to those in mLNs from unmanipulated wild-type recipients. Wild type mLNs transplanted into MHCII deficient syngeneic hosts sufficed to activate alloreactive T cells upon allogeneic hematopoietic cell transplantation, even in the absence of MHCII+ CD11c+ myeloid cells. These data support that orthotopically transplanted mLNs maintain physiological functions after transplantation. The technique of LN transplantation can be applied to study migratory and resident cell compartment interactions in mLNs as well as immune reactions from and to the gut under inflammatory and non-inflammatory conditions.}, language = {en} } @article{BaeuerleinQureischiMokhtarietal.2021, author = {B{\"a}uerlein, Carina A. and Qureischi, Musga and Mokhtari, Zeinab and Tabares, Paula and Brede, Christian and Jord{\´a}n Garrote, Ana-Laura and Riedel, Simone S. and Chopra, Martin and Reu, Simone and Mottok, Anja and Arellano-Viera, Estibaliz and Graf, Carolin and Kurzwart, Miriam and Schmiedgen, Katharina and Einsele, Hermann and W{\"o}lfl, Matthias and Schlegel, Paul-Gerhardt and Beilhack, Andreas}, title = {A T-Cell Surface Marker Panel Predicts Murine Acute Graft-Versus-Host Disease}, series = {Frontiers in Immunology}, volume = {11}, journal = {Frontiers in Immunology}, issn = {1664-3224}, doi = {10.3389/fimmu.2020.593321}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-224290}, year = {2021}, abstract = {Acute graft-versus-host disease (aGvHD) is a severe and often life-threatening complication of allogeneic hematopoietic cell transplantation (allo-HCT). AGvHD is mediated by alloreactive donor T-cells targeting predominantly the gastrointestinal tract, liver, and skin. Recent work in mice and patients undergoing allo-HCT showed that alloreactive T-cells can be identified by the expression of α4β7 integrin on T-cells even before manifestation of an aGvHD. Here, we investigated whether the detection of a combination of the expression of T-cell surface markers on peripheral blood (PB) CD8\(^+\) T-cells would improve the ability to predict aGvHD. To this end, we employed two independent preclinical models of minor histocompatibility antigen mismatched allo-HCT following myeloablative conditioning. Expression profiles of integrins, selectins, chemokine receptors, and activation markers of PB donor T-cells were measured with multiparameter flow cytometry at multiple time points before the onset of clinical aGvHD symptoms. In both allo-HCT models, we demonstrated a significant upregulation of α4β7 integrin, CD162E, CD162P, and conversely, a downregulation of CD62L on donor T-cells, which could be correlated with the development of aGvHD. Other surface markers, such as CD25, CD69, and CC-chemokine receptors were not found to be predictive markers. Based on these preclinical data from mouse models, we propose a surface marker panel on peripheral blood T-cells after allo-HCT combining α4β7 integrin with CD62L, CD162E, and CD162P (cutaneous lymphocyte antigens, CLA, in humans) to identify patients at risk for developing aGvHD early after allo-HCT.}, language = {en} } @article{DahlhoffManzSteinfattetal.2022, author = {Dahlhoff, Julia and Manz, Hannah and Steinfatt, Tim and Delgado-Tascon, Julia and Seebacher, Elena and Schneider, Theresa and Wilnit, Amy and Mokhtari, Zeinab and Tabares, Paula and B{\"o}ckle, David and Rasche, Leo and Martin Kort{\"u}m, K. and Lutz, Manfred B. and Einsele, Hermann and Brandl, Andreas and Beilhack, Andreas}, title = {Transient regulatory T-cell targeting triggers immune control of multiple myeloma and prevents disease progression}, series = {Leukemia}, volume = {36}, journal = {Leukemia}, number = {3}, issn = {1476-5551}, doi = {10.1038/s41375-021-01422-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-271787}, pages = {790-800}, year = {2022}, abstract = {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.}, language = {en} } @article{KalledaAmichArslanetal.2016, author = {Kalleda, Natarajaswamy and Amich, Jorge and Arslan, Berkan and Poreddy, Spoorthi and Mattenheimer, Katharina and Mokhtari, Zeinab and Einsele, Hermann and Brock, Matthias and Heinze, Katrin Gertrud and Beilhack, Andreas}, title = {Dynamic Immune Cell Recruitment After Murine Pulmonary Aspergillus fumigatus Infection under Different Immunosuppressive Regimens}, series = {Frontiers in Microbiology}, volume = {7}, journal = {Frontiers in Microbiology}, number = {1107}, doi = {10.3389/fmicb.2016.01107}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165368}, year = {2016}, abstract = {Humans are continuously exposed to airborne spores of the saprophytic fungus Aspergillus fumigatus. However, in healthy individuals pulmonary host defense mechanisms efficiently eliminate the fungus. In contrast, A. fumigatus causes devastating infections in immunocompromised patients. Host immune responses against A. fumigatus lung infections in immunocompromised conditions have remained largely elusive. Given the dynamic changes in immune cell subsets within tissues upon immunosuppressive therapy, we dissected the spatiotemporal pulmonary immune response after A. fumigatus infection to reveal basic immunological events that fail to effectively control invasive fungal disease. In different immunocompromised murine models, myeloid, notably neutrophils, and macrophages, but not lymphoid cells were strongly recruited to the lungs upon infection. Other myeloid cells, particularly dendritic cells and monocytes, were only recruited to lungs of corticosteroid treated mice, which developed a strong pulmonary inflammation after infection. Lymphoid cells, particularly CD4\(^+\) or CD8\(^+\) T-cells and NK cells were highly reduced upon immunosuppression and not recruited after A. fumigatus infection. Moreover, adoptive CD11b\(^+\) myeloid cell transfer rescued cyclophosphamide immunosuppressed mice from lethal A. fumigatus infection but not cortisone and cyclophosphamide immunosuppressed mice. Our findings illustrate that CD11b\(^+\) myeloid cells are critical for anti-A. fumigatus defense under cyclophosphamide immunosuppressed conditions.}, language = {en} }