@article{SoehnleinDrechslerDoeringetal.2013,
  author    = {Soehnlein, Oliver and Drechsler, Maik and D{\"o}ring, Yvonne and Lievens, Dirk and Hartwig, Helene and Kemmerich, Klaus and Ortega-G{\´o}mez, Almudena and Mandl, Manuela and Vijayan, Santosh and Projahn, Delia and Garlichs, Christoph D. and Koenen, Rory R. and Hristov, Mihail and Lutgens, Esther and Zernecke, Alma and Weber, Christian},
  title     = {Distinct functions of chemokine receptor axes in the atherogenic mobilization and recruitment of classical monocytes},
  series = {EMBO Molecular Medicine},
  volume    = {5},
  journal   = {EMBO Molecular Medicine},
  issn      = {1757-4676},
  doi       = {10.1002/emmm.201201717},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-122204},
  pages     = {471-481},
  year      = {2013},
  abstract  = {We used a novel approach of cytostatically induced leucocyte depletion and subsequent reconstitution with leucocytes deprived of classical \((inflammatory/Gr1^{hi})\) or non-classical \((resident/Gr1^{lo})\) monocytes to dissect their differential role in atheroprogression under high-fat diet (HFD). Apolipoprotein E-deficient \((Apoe^{-/-})\) mice lacking classical but not non-classical monocytes displayed reduced lesion size and macrophage and apoptotic cell content. Conversely, HFD induced a selective expansion of classical monocytes in blood and bone marrow. Increased CXCL1 levels accompanied by higher expression of its receptor CXCR2 on classical monocytes and inhibition of monocytosis by CXCL1-neutralization indicated a preferential role for the CXCL1/CXCR2 axis in mobilizing classical monocytes during hypercholesterolemia. Studies correlating circulating and lesional classical monocytes in gene-deficient \(Apoe^{-/-}\) mice, adoptive transfer of gene-deficient cells and pharmacological modulation during intravital microscopy of the carotid artery revealed a crucial function of CCR1 and CCR5 but not CCR2 or \(CX_3CR1\) in classical monocyte recruitment to atherosclerotic vessels. Collectively, these data establish the impact of classical monocytes on atheroprogression, identify a sequential role of CXCL1 in their mobilization and CCR1/CCR5 in their recruitment.},
  language  = {en}
}
@article{Zernecke2014,
  author    = {Zernecke, Alma},
  title     = {Distinct functions of specialized dendritic cell subsets in atherosclerosis and the road ahead},
  series = {Scientifica},
  volume    = {2014},
  journal   = {Scientifica},
  doi       = {10.1155/2014/952625},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120241},
  pages     = {952625},
  year      = {2014},
  abstract  = {Atherosclerotic vascular disease is modulated by immune mechanisms. Dendritic cells (DCs) and T cells are present within atherosclerotic lesions and function as central players in the initiation and modulation of adaptive immune responses. In previous years, we have studied the functional contribution of distinct DC subsets in disease development, namely, that of CCL17-expressing DCs as well as that of plasmacytoid DCs that play specialized roles in disease development. This review focuses on important findings gathered in these studies and dissects the multifaceted contribution of CCL17-expressing DCs and pDCs to the pathogenesis of atherosclerosis. Furthermore, an outlook on future challenges faced when studying DCs in this detrimental disease are provided, and hurdles that will need to be overcome in order to enable a better understanding of the contribution of DCs to atherogenesis are discussed, a prerequisite for their therapeutic targeting in atherosclerosis.},
  language  = {en}
}
@article{BuschWesthofenKochetal.2014,
  author    = {Busch, Martin and Westhofen, Thilo C. and Koch, Miriam and Lutz, Manfred B. and Zernecke, Alma},
  title     = {Dendritic Cell Subset Distributions in the Aorta in Healthy and Atherosclerotic Mice},
  series = {PLoS ONE},
  volume    = {9},
  journal   = {PLoS ONE},
  number    = {2},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0088452},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119907},
  pages     = {e88452},
  year      = {2014},
  abstract  = {Dendritic cells (DCs) can be sub-divided into various subsets that play specialized roles in priming of adaptive immune responses. Atherosclerosis is regarded as a chronic inflammatory disease of the vessel wall and DCs can be found in non-inflamed and diseased arteries. We here performed a systematic analyses of DCs subsets during atherogenesis. Our data indicate that distinct DC subsets can be localized in the vessel wall. In C57BL/6 and low density lipoprotein receptor-deficient (Ldlr-/-) mice, CD11c+ MHCII+ DCs could be discriminated into CD103- CD11b+F4/80+, CD11b+F4/80- and CD11b-F4/80- DCs and CD103+ CD11b-F4/80- DCs. Except for CD103- CD11b- F4/80- DCs, these subsets expanded in high fat diet-fed Ldlr-/- mice. Signal-regulatory protein (Sirp)-α was detected on aortic macrophages, CD11b+ DCs, and partially on CD103- CD11b- F4/80- but not on CD103+ DCs. Notably, in FMS-like tyrosine kinase 3-ligand-deficient (Flt3l-/-) mice, a specific loss of CD103+ DCs but also CD103- CD11b+ F4/80- DCs was evidenced. Aortic CD103+ and CD11b+ F4/80- CD103- DCs may thus belong to conventional rather than monocyte-derived DCs, given their dependence on Flt3L-signalling. CD64, postulated to distinguish macrophages from DCs, could not be detected on DC subsets under physiological conditions, but appeared in a fraction of CD103- CD11b+ F4/80- and CD11b+ F4/80+ cells in atherosclerotic Ldlr-/- mice. The emergence of CD64 expression in atherosclerosis may indicate that CD11b+ F4/80- DCs similar to CD11b+ F4/80+ DCs are at least in part derived from immigrated monocytes during atherosclerotic lesion formation. Our data advance our knowledge about the presence of distinct DC subsets and their accumulation characteristics in atherosclerosis, and may help to assist in future studies aiming at specific DC-based therapeutic strategies for the treatment of chronic vascular inflammation.},
  language  = {en}
}
@article{CochainChaudhariKochetal.2014,
  author    = {Cochain, Clement and Chaudhari, Sweena M. and Koch, Miriam and Wiendl, Heinz and Eckstein, Hans-Henning and Zernecke, Alma},
  title     = {Programmed Cell Death-1 Deficiency Exacerbates T Cell Activation and Atherogenesis despite Expansion of Regulatory T Cells in Atherosclerosis-Prone Mice},
  series = {PLoS ONE},
  volume    = {9},
  journal   = {PLoS ONE},
  number    = {4},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0093280},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119823},
  pages     = {e93280},
  year      = {2014},
  abstract  = {T cell activation represents a double-edged sword in atherogenesis, as it promotes both pro-inflammatory T cell activation and atheroprotective Foxp3(+) regulatory T cell (Treg) responses. Here, we investigated the role of the co-inhibitory receptor programmed cell death-1 (PD-1) in T cell activation and CD4(+) T cell polarization towards pro-atherogenic or atheroprotective responses in mice. Mice deficient for both low density lipoprotein receptor and PD-1 (Ldlr(-/-)Pd1(-/-)) displayed striking increases in systemic CD4(+) and CD8(+) T cell activation after 9 weeks of high fat diet feeding, associated with an expansion of both pro-atherogenic IFNγ-secreting T helper 1 cells and atheroprotective Foxp3+ Tregs. Importantly, PD-1 deficiency did not affect Treg suppressive function in vitro. Notably, PD-1 deficiency exacerbated atherosclerotic lesion growth and entailed a massive infiltration of T cells in atherosclerotic lesions. In addition, aggravated hypercholesterolemia was observed in Ldlr(-/-)Pd1(-/-) mice. In conclusion, we here demonstrate that although disruption of PD-1 signaling enhances both pro- and anti-atherogenic T cell responses in Ldlr(-/-) mice, pro-inflammatory T cell activation prevails and enhances dyslipidemia, vascular inflammation and atherosclerosis.},
  language  = {en}
}
@article{ProjahnSimsekyilmazSinghetal.2014,
  author    = {Projahn, Delia and Simsekyilmaz, Sakine and Singh, Smriti and Kanzler, Isabella and Kramp, Birgit K. and Langer, Marcella and Burlacu, Alexandrina and Bernhagen, J{\"u}rgen and Klee, Doris and Zernecke, Alma and Hackeng, Tilman M. and Groll, J{\"u}rgen and Weber, Christian and Liehn, Elisa A. and Koenen, Roy R.},
  title     = {Controlled intramyocardial release of engineered chemokines by biodegradable hydrogels as a treatment approach of myocardial infarction},
  series = {Journal of Cellular and Molecular Medicine},
  volume    = {18},
  journal   = {Journal of Cellular and Molecular Medicine},
  number    = {5},
  issn      = {1582-4934},
  doi       = {10.1111/jcmm.12225},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-116597},
  pages     = {790-800},
  year      = {2014},
  abstract  = {Myocardial infarction (MI) induces a complex inflammatory immune response, followed by the remodelling of the heart muscle and scar formation. The rapid regeneration of the blood vessel network system by the attraction of hematopoietic stem cells is beneficial for heart function. Despite the important role of chemokines in these processes, their use in clinical practice has so far been limited by their limited availability over a long time-span in vivo. Here, a method is presented to increase physiological availability of chemokines at the site of injury over a defined time-span and simultaneously control their release using biodegradable hydrogels. Two different biodegradable hydrogels were implemented, a fast degradable hydrogel (FDH) for delivering Met-CCL5 over 24hrs and a slow degradable hydrogel (SDH) for a gradual release of protease-resistant CXCL12 (S4V) over 4weeks. We demonstrate that the time-controlled release using Met-CCL5-FDH and CXCL12 (S4V)-SDH suppressed initial neutrophil infiltration, promoted neovascularization and reduced apoptosis in the infarcted myocardium. Thus, we were able to significantly preserve the cardiac function after MI. This study demonstrates that time-controlled, biopolymer-mediated delivery of chemokines represents a novel and feasible strategy to support the endogenous reparatory mechanisms after MI and may compliment cell-based therapies.},
  language  = {en}
}
@article{RowinskaGorressenMerxetal.2014,
  author    = {Rowinska, Zuzanna and Gorressen, Simone and Merx, Marc W. and Koeppel, Thomas A. and Liehn, Elisa A. and Zernecke, Alma},
  title     = {Establishment of a New Murine Elastase-Induced Aneurysm Model Combined with Transplantation},
  series = {PLOS ONE},
  volume    = {9},
  journal   = {PLOS ONE},
  number    = {7},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0102648},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-115774},
  pages     = {e102648},
  year      = {2014},
  abstract  = {Introduction: The aim of our study was to develop a reproducible murine model of elastase-induced aneurysm formation combined with aortic transplantation. Methods: Adult male mice (n = 6-9 per group) underwent infrarenal, orthotopic transplantation of the aorta treated with elastase or left untreated. Subsequently, both groups of mice were monitored by ultrasound until 7 weeks after grafting. Results: Mice receiving an elastase-pretreated aorta developed aneurysms and exhibited a significantly increased diastolic vessel diameter compared to control grafted mice at 7 week after surgery (1.11 +/- 0.10 mm vs. 0.75 +/- 0.03 mm; p <= 0.001). Histopathological examination revealed disruption of medial elastin, an increase in collagen content and smooth muscle cells, and neointima formation in aneurysm grafts. Conclusions: We developed a reproducible murine model of elastase-induced aneurysm combined with aortic transplantation. This model may be suitable to investigate aneurysm-specific inflammatory processes and for use in gene-targeted animals.},
  language  = {en}
}
@article{TilstamGijbelsHabbeddineetal.2014,
  author    = {Tilstam, Pathricia V. and Gijbels, Marion J. and Habbeddine, Mohamed and Cudejko, Celine and Asare, Yaw and Theelen, Wendy and Zhou, Baixue and D{\"o}ring, Yvonne and Drechsler, Maik and Pawig, Lukas and Simsekyilmaz, Sakine and Koenen, Rory R. and de Winther, Menno P. J. and Lawrence, Toby and Bernhagen, J{\"u}rgen and Zernecke, Alma and Weber, Christian and Noels, Heidi},
  title     = {Bone Marrow-Specific Knock-In of a Non-Activatable Ikkα Kinase Mutant Influences Haematopoiesis but Not Atherosclerosis in Apoe-Deficient Mice},
  series = {PLOS ONE},
  volume    = {9},
  journal   = {PLOS ONE},
  number    = {2},
  doi       = {10.1371/journal.pone.0087452},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117450},
  pages     = {e87452},
  year      = {2014},
  abstract  = {Background: The Ikkα kinase, a subunit of the NF-kappa B-activating IKK complex, has emerged as an important regulator of inflammatory gene expression. However, the role of Ikkα-mediated phosphorylation in haematopoiesis and atherogenesis remains unexplored. In this study, we investigated the effect of a bone marrow (BM)-specific activation-resistant Ikk alpha mutant knock-in on haematopoiesis and atherosclerosis in mice. Methods and Results: Apolipoprotein E (Apoe)-deficient mice were transplanted with BM carrying an activation-resistant Ikkα gene (Ikkα(AA/AA) Apoe(-/-)) or with Ikkα(+/+) Apoe(-/-) BM as control and were fed a high-cholesterol diet for 8 or 13 weeks. Interestingly, haematopoietic profiling by flow cytometry revealed a significant decrease in B-cells, regulatory T-cells and effector memory T-cells in Ikkα(AA/AA) Apoe(-/-) BM-chimeras, whereas the naive T-cell population was increased. Surprisingly, no differences were observed in the size, stage or cellular composition of atherosclerotic lesions in the aorta and aortic root of Ikkα(AA/AA) Apoe(-/-) vs Ikkα(+/+) Apoe(-/-) BM-transplanted mice, as shown by histological and immunofluorescent stainings. Necrotic core sizes, apoptosis, and intracellular lipid deposits in aortic root lesions were unaltered. In vitro, BM-derived macrophages from Ikkα(AA/AA) Apoe(-/-) vs Ikkα(+/+) Apoe(-/-) mice did not show significant differences in the uptake of oxidized low-density lipoproteins (oxLDL), and, with the exception of Il-12, the secretion of inflammatory proteins in conditions of Tnf-α or oxLDL stimulation was not significantly altered. Furthermore, serum levels of inflammatory proteins as measured with a cytokine bead array were comparable. Conclusion: Our data reveal an important and previously unrecognized role of haematopoietic Ikkα kinase activation in the homeostasis of B-cells and regulatory T-cells. However, transplantation of Ikkα AA mutant BM did not affect atherosclerosis in Apoe(-/-) mice. This suggests that the diverse functions of Ikkα in haematopoietic cells may counterbalance each other or may not be strong enough to influence atherogenesis, and reveals that targeting haematopoietic Ikkα kinase activity alone does not represent a therapeutic approach.},
  language  = {en}
}
@article{BuschBuschScholzetal.2016,
  author    = {Busch, Albert and Busch, Martin and Scholz, Claus-J{\"u}rgen and Kellersmann, Richard and Otto, Christoph and Chernogubova, Ekaterina and Maegdefessel, Lars and Zernecke, Alma and Lorenz, Udo},
  title     = {Aneurysm miRNA Signature Differs, Depending on Disease Localization and Morphology},
  series = {International Journal of Molecular Science},
  volume    = {17},
  journal   = {International Journal of Molecular Science},
  number    = {1},
  issn      = {International Journal of Molecular Science},
  doi       = {10.3390/ijms17010081},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146422},
  pages     = {81},
  year      = {2016},
  abstract  = {Limited comprehension of aneurysm pathology has led to inconclusive results from clinical trials. miRNAs are key regulators of post-translational gene modification and are useful tools in elucidating key features of aneurysm pathogenesis in distinct entities of abdominal and popliteal aneurysms. Here, surgically harvested specimens from 19 abdominal aortic aneurysm (AAA) and 8 popliteal artery aneurysm (PAA) patients were analyzed for miRNA expression and histologically classified regarding extracellular matrix (ECM) remodeling and inflammation. DIANA-based computational target prediction and pathway enrichment analysis verified our results, as well as previous ones. miRNA-362, -19b-1, -194, -769, -21 and -550 were significantly down-regulated in AAA samples depending on degree of inflammation. Similar or inverse regulation was found for miR-769, 19b-1 and miR-550, -21, whereas miR-194 and -362 were unaltered in PAA. In situ hybridization verified higher expression of miR-550 and -21 in PAA compared to AAA and computational analysis for target genes and pathway enrichment affirmed signal transduction, cell-cell-interaction and cell degradation pathways, in line with previous results. Despite the vague role of miRNAs for potential diagnostic and treatment purposes, the number of candidates from tissue signature studies is increasing. Tissue morphology influences subsequent research, yet comparison of distinct entities of aneurysm disease can unravel core pathways.},
  language  = {en}
}
@article{EndresKneitzOrthetal.2016,
  author    = {Endres, Marcel and Kneitz, Susanne and Orth, Martin F. and Perera, Ruwan K. and Zernecke, Alma and Butt, Elke},
  title     = {Regulation of matrix metalloproteinases (MMPs) expression and secretion in MDA-MB-231 breast cancer cells by LIM and SH3 protein 1 (LASP1)},
  series = {Oncotarget},
  volume    = {7},
  journal   = {Oncotarget},
  number    = {39},
  doi       = {10.18632/oncotarget.11720},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176920},
  pages     = {64244-64259},
  year      = {2016},
  abstract  = {The process of tumor invasion requires degradation of extracellular matrix by proteolytic enzymes. Cancer cells form protrusive invadopodia, which produce and release matrix metalloproteinases (MMPs) to degrade the basement membrane thereby enabling metastasis. We investigated the effect of LASP1, a newly identified protein in invadopodia, on expression, secretion and activation of MMPs in invasive breast tumor cell lines. By analyzing microarray data of in-house generated control and LASP1-depleted MDA-MB-231 breast cancer cells, we observed downregulation of MMP1, -3 and -9 upon LASP1 depletion. This was confirmed by Western blot analysis. Conversely, rescue experiments restored in part MMP expression and secretion. The regulatory effect of LASP1 on MMP expression was also observed in BT-20 breast cancer cells as well as in prostate and bladder cancer cell lines. In line with bioinformatic FunRich analysis of our data, which mapped a high regulation of transcription factors by LASP1, public microarray data analysis detected a correlation between high LASP1 expression and enhanced c-Fos levels, a protein that is part of the transcription factor AP-1 and known to regulate MMP expression. Compatibly, in luciferase reporter assays, AP-1 showed a decreased transcriptional activity after LASP1 knockdown. Zymography assays and Western blot analysis revealed an additional promotion of MMP secretion into the extracellular matrix by LASP1, thus, most likely, altering the microenvironment during cancer progression. The newly identified role of LASP1 in regulating matrix degradation by affecting MMP transcription and secretion elucidated the migratory potential of LASP1 overexpressing aggressive tumor cells in earlier studies.},
  language  = {en}
}
@article{SimsekyilmazLiehnWeinandyetal.2016,
  author    = {Simsekyilmaz, Sakine and Liehn, Elisa A. and Weinandy, Stefan and Schreiber, Fabian and Megens, Remco T. A. and Theelen, Wendy and Smeets, Ralf and Jockenh{\"o}vel, Stefan and Gries, Thomas and M{\"o}ller, Martin and Klee, Doris and Weber, Christian and Zernecke, Alma},
  title     = {Targeting In-Stent-Stenosis with RGD- and CXCL1-Coated Mini-Stents in Mice},
  series = {PLoS ONE},
  volume    = {11},
  journal   = {PLoS ONE},
  number    = {5},
  doi       = {10.1371/journal.pone.0155829},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-179745},
  year      = {2016},
  abstract  = {Atherosclerotic lesions that critically narrow the artery can necessitate an angioplasty and stent implantation. Long-term therapeutic effects, however, are limited by excessive arterial remodeling. We here employed a miniaturized nitinol-stent coated with star-shaped polyethylenglycole (star-PEG), and evaluated its bio-functionalization with RGD and CXCL1 for improving in-stent stenosis after implantation into carotid arteries of mice. Nitinol foils or stents (bare metal) were coated with star-PEG, and bio-functionalized with RGD, or RGD/CXCL1. Cell adhesion to star-PEG-coated nitinol foils was unaltered or reduced, whereas bio-functionalization with RGD but foremost RGD/CXCL1 increased adhesion of early angiogenic outgrowth cells (EOCs) and endothelial cells but not smooth muscle cells when compared with bare metal foils. Stimulation of cells with RGD/CXCL1 furthermore increased the proliferation of EOCs. In vivo, bio-functionalization with RGD/CXCL1 significantly reduced neointima formation and thrombus formation, and increased re-endothelialization in apoE\(^{-/-}\) carotid arteries compared with bare-metal nitinol stents, star-PEG-coated stents, and stents bio-functionalized with RGD only. Bio-functionalization of star-PEG-coated nitinol-stents with RGD/CXCL1 reduced in-stent neointima formation. By supporting the adhesion and proliferation of endothelial progenitor cells, RGD/CXCL1 coating of stents may help to accelerate endothelial repair after stent implantation, and thus may harbor the potential to limit the complication of in-stent restenosis in clinical approaches.},
  language  = {en}
}