Institute for Experimental Medicine

Kiel, Germany

Institute for Experimental Medicine

Kiel, Germany
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Oberg H.-H.,University of Kiel | Sebens S.,Institute for Experimental Medicine | Krause S.,University of Kiel | Petrick D.,University of Kiel | And 8 more authors.
Cancer Research | Year: 2014

The ability of human gd T cells from healthy donors to kill pancreatic ductal adenocarcinoma (PDAC) in vitro and in vivo in immunocompromised mice requires the addition of gd T-cell-stimulating antigens. In this study, we demonstrate that gd T cells isolated from patients with PDAC tumor infiltrates lyse pancreatic tumor cells after selective stimulation with phosphorylated antigens. We determined the absolute numbers of gd T-cell subsets in patient whole blood and applied a real-time cell analyzer to measure their cytotoxic effector function over prolonged time periods. Because phosphorylated antigens did not optimally enhance gd T-cell cytotoxicity, we designed bispecific antibodies that bind CD3 or Vg9 on gd T cells and Her2/neu (ERBB2) expressed by pancreatic tumor cells. Both antibodies enhanced gd T-cell cytotoxicity with the Her2/Vg9 antibody also selectively enhancing release of granzyme B and perforin. Supporting these observations, adoptive transfer of gd T cells with the Her2/Vg9 antibody reduced growth of pancreatic tumors grafted into SCID-Beige immunocompromised mice. Taken together, our results show how bispecific antibodies that selectively recruit gd T cells to tumor antigens expressed by cancer cells illustrate the tractable use of endogenous gd T cells for immunotherapy. © 2013 American Association for Cancer Research.

Adas G.,Okmeydani Education and Research Hospital | Arikan S.,Istanbul Education and Research Hospital | Karatepe O.,Okmeydani Education and Research Hospital | Kemik O.,Okmeydani Education and Research Hospital | And 4 more authors.
Langenbeck's Archives of Surgery | Year: 2011

Objective: The goal of this study is to examine if allogenic mesenchymal stem cell (MSC) transplantation is a useful therapy for left ischemic colon anastomosis in rats. Summary and background data: Problems with anastomosis healing may lead to serious postoperative complications. Bone marrow-derived mesenchymal stem cells (BM-MSCs), which are also referred to as stromal progenitor cells, are self-renewing and expandable stem cells. Recent studies have suggested that BM-MSCs play a crucial role in the processes of intestinal repair and accelerate angiogenesis. Methods: MSCs were isolated from rats before analysis by light and scanning electron microscopy. Forty male Wistar albino rats weighing 250-280 g were divided into four equal groups (n=10) as follows: group 1: control, ischemic left colonic anastomoses (fourth day); group 2: control, ischemic left colonic anastomoses (seventh day); group 3: ischemic left colonic anastomoses + locally transplanted BM-MSCs (fourth day); group 4: ischemic left colonic anastomoses + locally transplanted BM-MSCs (seventh day). Histopathological features and anastomotic strength were evaluated. Results: BM-MSCs therapy significantly accelerated all of the healing parameters for ischemic colonic anastomosis except for inflammation on the fourth day. On the seventh day, BM-MSCs augmented the levels of the hydroxyproline and bursting pressure. Histological parameters, especially angiogenesis, were also found to be important for healing of ischemic colonic anastomoses. Conclusions: This is the first study to use locally transplanted cell therapy for the healing of ischemic colonic anastomosis. BM-MSCs therapy significantly accelerated all of the healing parameters for ischemic colonic anastomosis. © 2010 Springer-Verlag.

Schafer H.,Laboratory of Molecular Gastroenterology and Hepatology | Struck B.,Laboratory of Molecular Gastroenterology and Hepatology | Struck B.,Institute for Experimental Medicine | Feldmann E.-M.,Laboratory of Molecular Gastroenterology and Hepatology | And 9 more authors.
Oncogene | Year: 2013

Patients with chronic inflammatory bowel disease (IBD) have an increased risk to develop colorectal cancer (CRC) particularly after long duration of the disease. Chronic inflammation of the intestinal mucosa is characterized by a marked enrichment of immune cells such as macrophages as well as by high expression of cytokines and growth factors including transforming growth factor-beta 1 (TGF-β1). The adhesion molecule L1CAM mediates chemoresistance and migration of tumor cells and is elevated in CRC tissues being associated with metastatic spread and poor prognosis for the patients. In this study, we examine the role of TGF-β1-induced L1CAM expression and macrophages in malignant transformation of intestinal epithelial cells. We demonstrate that TGF-β1 stimulation leads to a Slug-dependent upregulation of L1CAM expression already in the colonic intestinal epithelial cell line NCM460 thereby enhancing cell motility and apoptosis resistance. Accordingly, NCM460 cells acquired a migratory and apoptosis-resistant phenotype if transfected with L1CAM. Immunohistochemistry of colonic biopsies revealed considerable L1CAM expression in intestinal epithelial cells in tissues from IBD patients but not in normal colonic tissues. Moreover, L1CAM expression increased with duration of disease being associated with the presence of CD33+ macrophages. Coculture with macrophages generated from monocyte colony-stimulating factor (MCSF)-treated monocytes led to the upregulation of Slug and L1CAM in NCM460 cells thereby elevating cell motility and apoptosis resistance. Pharmacological inhibition of TGF-β1 signalling abolished expression of Slug and L1CAM in cocultured NCM460 cells resulting in decreased cell migration and apoptosis resistance. In conclusion, these data provide new insights into the mechanisms by which IBD promotes malignant transformation of intestinal epithelial cells and underscore the role of L1CAM and macrophages in this scenario. © 2013 Macmillan Publishers Limited All rights reserved.

Schafer H.,Laboratory of Molecular Gastroenterology and Hepatology | Dieckmann C.,Laboratory of Molecular Gastroenterology and Hepatology | Korniienko O.,Institute for Experimental Cancer Research | Moldenhauer G.,German Cancer Research Center | And 6 more authors.
Cancer Letters | Year: 2012

The adhesion molecule L1CAM (CD171) accounts for enhanced motility, invasiveness and chemoresistance of tumor cells and represents a novel marker for various tumor entities including pancreatic and ovarian carcinoma. Recently, we showed that L1CAM inhibition increases the apoptotic response of tumor cells towards cytostatic drugs pointing to the potential of L1CAM to serve as a chemosensitizer in anti-cancer therapy. Thus, the present study evaluated the therapeutic potential of combined treatment with L1CAM antibodies and chemotherapeutic drugs in pancreatic and ovarian carcinoma model systems. in vivo. Two L1CAM-specific antibodies (L1-14.10 and L1-9.3/2a) exhibiting high binding affinity to the L1CAM expressing pancreatic adenocarcinoma cell line Colo357 and the ovarian carcinoma cell line SKOV3ip were used for treatment. The combined therapy of SCID mice with either L1CAM antibody and gemcitabine and paclitaxel, respectively, reduced the growth of subcutaneously grown Colo357 or SKOV3ip tumors more efficiently than treatment with the cytostatic drug alone or in combination with control IgG. This was accompanied by an increased number of apoptotic tumor cells along with an elevated procaspase-8 expression. Furthermore, a lowered activation of NF-κB along with a reduced expression of VEGF and a diminished number of CD31-positive blood vessels were observed in tumors after combined therapy compared to control treatments, while the infiltration of F4/80-positive macrophages increased. Overall, these data provide new insights into the mechanism of the anti-cancer activity of L1CAM-blocking antibodies. in vivo and support the suitability of L1CAM as a target for chemosensitization and of L1CAM-interfering antibodies as an appropriate tool to increase the therapeutic response of pancreatic and ovarian carcinoma. © 2011 Elsevier Ireland Ltd.

Weinspach D.,TU Munich | Seubert B.,TU Munich | Schaten S.,TU Munich | Honert K.,TU Munich | And 3 more authors.
Clinical and Experimental Metastasis | Year: 2014

Expression of the L1 cell adhesion molecule (L1CAM) is frequently increased in cancer patients compared to healthy individuals and also linked with bad prognosis of solid tumours. Previously, we could show that full-length L1CAM promotes metastasis formation via up-regulation of gelatinolytic activity in fibrosarcoma. In this study, we aimed to extend this finding to haematogenous malignancies and carcinomas, and to specifically elucidate the impact of L1CAM on major steps of the metastatic cascade. In a well-established T-cell lymphoma spontaneous metastasis model, silencing of L1CAM significantly improved survival of the mice, while intradermal tumour growth remained unaltered. This correlated with significantly decreased spontaneous metastasis formation. L1CAM suppression abrogated the metastatic potential of T-cell lymphoma as well as carcinoma cells as demonstrated by reduced migration and invasion in vitro and reduced formation of experimental metastasis in vivo. At the molecular level, silencing of L1CAM led to reduced expression of gelatinases MMP-2 and -9 in vitro and decreased gelatinolytic activity in primary tumours and metastases in vivo. In accordance, knock down of L1CAM had similar suppressive effects on migration, invasion and in vivo-gelatinolytic activity as treatment with the specific gelatinase inhibitor SB-3CT. This newly discovered impact of L1CAM on distinct steps of the metastatic cascade and MMP activity highlights the potential of possible L1CAM-directed therapies to inhibit metastatic spread. © 2013 Springer Science+Business Media Dordrecht.

Helm O.,Institute for Experimental Medicine | Held-Feindt J.,UKSH Campus Kiel | Schafer H.,Laboratory of Molecular Gastroenterology and Hepatology | Sebens S.,Institute for Experimental Medicine
OncoImmunology | Year: 2014

We recently identified tumor-associated macrophages from pancreatic ductal adenocarcinoma sharing pro- and anti-inflammatory characteristics. Already in residence in the setting of chronic pancreatitis, local macrophages confer malignancy-associated features to premalignant pancreatic ductal epithelial cells by both promoting and inhibiting inflammation, either of which can foster malignant conversion. Our findings support the concept that contrasting modes of inflammation can promote tumorigenesis. © 2014 Taylor & Francis Group, LLC.

Grage-Griebenow E.,Institute for Experimental Medicine | Schafer H.,Laboratory of Molecular Gastroenterology and Hepatology | Sebens S.,Institute for Experimental Medicine
OncoImmunology | Year: 2014

Immune evasion is a hallmark of cancer. We recently identified the adhesion molecule L1CAM as biomarker of pancreatic ductal adenocarcinoma (PDAC) associated with poor prognosis. During inflammation-associated carcinogenesis, L1CAM drives the enrichment of highly immunosuppressive CD4+CD25-CD69+ T cells. Thus, L1CAM may serve as a target in immunomodulatory therapy for PDAC. © 2014 Landes Bioscience.

Sass V.,University of Bonn | Schneider T.,University of Bonn | Wilmes M.,University of Bonn | Korner C.,University of Bonn | And 4 more authors.
Infection and Immunity | Year: 2010

Human β-defensin 3 (hBD3) is a highly charged (+11) cationic host defense peptide, produced by epithelial cells and neutrophils. hBD3 retains antimicrobial activity against a broad range of pathogens, including multiresistant Staphylococcus aureus, even under high-salt conditions. Whereas antimicrobial host defense peptides are assumed to act by permeabilizing cell membranes, the transcriptional response pattern of hBD3-treated staphylococcal cells resembled that of vancomycin-treated cells (V. Sass, U. Pag, A. Tossi, G. Bierbaum, and H. G. Sahl, Int. J. Med. Microbiol. 298:619-633, 2008) and suggested that inhibition of cell wall biosynthesis is a major component of the killing process. hBD3-treated cells, inspected by transmission electron microscopy, showed localized protrusions of cytoplasmic contents, and analysis of the intracellular pool of nucleotide-activated cell wall precursors demonstrated accumulation of the final soluble precursor, UDP-MurNAc- pentapeptide. Accumulation is typically induced by antibiotics that inhibit membrane-bound steps of cell wall biosynthesis and also demonstrates that hBD3 does not impair the biosynthetic capacity of cells and does not cause gross leakage of small cytoplasmic compounds. In in vitro assays of individual membrane-associated cell wall biosynthesis reactions (MraY, MurG, FemX, and penicillin-binding protein 2 [PBP2]), hBD3 inhibited those enzymes which use the bactoprenol-bound cell wall building block lipid II as a substrate; quantitative analysis suggested that hBD3 may stoichiometrically bind to lipid II. We report that binding of hBD3 to defined, lipid II-rich sites of cell wall biosynthesis may lead to perturbation of the biosynthesis machinery, resulting in localized lesions in the cell wall as demonstrated by electron microscopy. The lesions may then allow for osmotic rupture of cells when defensins are tested under low-salt conditions. Copyright © 2010, American Society for Microbiology. All Rights Reserved.

Mannell H.,Ludwig Maximilians University of Munich | Hammitzsch A.,Institute for Experimental Medicine | Hammitzsch A.,Ludwig Maximilians University of Munich | Mettler R.,Ludwig Maximilians University of Munich | And 2 more authors.
Cellular Signalling | Year: 2010

Angiogenesis initiation is crucially dependent on endothelial proliferation and can be stimulated by the fibroblast growth factor 2 (FGF-2). The DNA dependent protein kinase (DNA-PK), long known for its importance in repairing DNA double strand breaks, belongs to the phosphatidylinositol-3 kinase (PI3-K) super family and has recently been identified as one of the enzymes phosphorylating and activating Akt. Due to its similarity with PI3-K, we hypothesized that DNA-PK may have similar effects on endothelial angiogenic processes and signalling. We used primary endothelial cells (HUVEC and PAEC) and human microvascular endothelial cells (HMEC) to study the role of DNA-PK in endothelial proliferation and signalling. DNA-PKcs suppression with the compound NU7026 or with siRNA induced basal endothelial cell proliferation as well as enhanced FGF-2 dependent proliferation. This was associated with an increase in phosphorylated Akt. Tube formation was not affected by DNA-PKcs clearly showing that the role of DNA-PK in endothelial processes differs from that of PI3-K. Our findings indicate DNA-PK as an important enzyme maintaining the quiescent endothelial phenotype by actively inhibiting Akt thus restraining endothelial cell proliferation preventing excessive growth. © 2009 Elsevier Inc. All rights reserved.

Kidgotko O.V.,Institute for Experimental Medicine | Kustova M.Y.,Institute for Experimental Medicine | Sokolova V.A.,Institute for Experimental Medicine | Bass M.G.,Institute for Experimental Medicine | Vasilyev V.B.,Institute for Experimental Medicine
Mitochondrion | Year: 2013

Previously we obtained heteroplasmic mice carrying murine and human mitochondrial DNA (mtDNA). Even the fourth generation of such mice had human mtDNA in their organs, hence, they were used to study the possibility of paternal mtDNA transmission. A lineage was obtained in which human mtDNA was transmitted by males to the progeny in four successive generations. This is the first observation of such a continuous paternal transmission of mtDNA. Persistence of paternal mtDNA in several successive generations of animals suggests that mechanisms aimed at elimination of paternally inherited mtDNA species are not as strict as has been postulated. © 2013 Elsevier B.V.

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