@article{PalettaFichtnerStaricketal.2015,
  author    = {Paletta, Daniel and Fichtner, Alina Suzann and Starick, Lisa and Porcelli, Steven A. and Savage, Paul B. and Herrmann, Thomas},
  title     = {Species Specific Differences of CD1d Oligomer Loading In Vitro},
  series = {PLoS One},
  volume    = {10},
  journal   = {PLoS One},
  number    = {11},
  doi       = {10.1371/journal.pone.0143449},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-124879},
  pages     = {e0143449},
  year      = {2015},
  abstract  = {CD1d molecules are MHC class I-like molecules that present glycolipids to iNKT cells. The highly conserved interaction between CD1d:α-Galactosylceramide (αGC) complexes and the iNKT TCR not only defines this population of αβ T cells but can also be used for its direct identification. Therefore, CD1d oligomers are a widely used tool for iNKT cell related investigations. To this end, the lipid chains of the antigen have to be inserted into the hydrophobic pockets of the CD1d binding cleft, often with help of surfactants. In this study, we investigated the influence of different surfactants (Triton X-100, Tween 20, Tyloxapol) on in vitro loading of CD1d molecules derived from four different species (human, mouse, rat and cotton rat) with αGC and derivatives carrying modifications of the acyl-chain (DB01-1, PBS44) and a 6-acetamido-6-deoxy-addition at the galactosyl head group (PBS57). We also compared rat CD1d dimers with tetramers and staining of an iNKT TCR transductant was used as readout for loading efficacy. The results underlined the importance of CD1d loading efficacy for proper analysis of iNKT TCR binding and demonstrated the necessity to adjust loading conditions for each oligomer/glycolipid combination. The efficient usage of surfactants as a tool for CD1d loading was revealed to be species-specific and depending on the origin of the CD1d producing cells. Additional variation of surfactant-dependent loading efficacy between tested glycolipids was influenced by the acyl-chain length and the modification of the galactosyl head group with PBS57 showing the least dependence on surfactants and the lowest degree of species-dependent differences.},
  language  = {en}
}
@article{SchubertUnkmeirSchneiderSchauliesGulbinsetal.2014,
  author    = {Schubert-Unkmeir, Alexandra and Schneider-Schaulies, Sibylle and Gulbins, Erich and Hebling, Sabrina and Simonis, Alexander},
  title     = {Differential Activation of Acid Sphingomyelinase and Ceramide Release Determines Invasiveness of Neisseria meningitidis into Brain Endothelial Cells},
  doi       = {10.1371/journal.ppat.1004160},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-113031},
  year      = {2014},
  abstract  = {The interaction with brain endothelial cells is central to the pathogenicity of Neisseria meningitidis infections. Here, we show that N. meningitidis causes transient activation of acid sphingomyelinase (ASM) followed by ceramide release in brain endothelial cells. In response to N. meningitidis infection, ASM and ceramide are displayed at the outer leaflet of the cell membrane and condense into large membrane platforms which also concentrate the ErbB2 receptor. The outer membrane protein Opc and phosphatidylcholine-specific phospholipase C that is activated upon binding of the pathogen to heparan sulfate proteoglycans, are required for N. meningitidis-mediated ASM activation. Pharmacologic or genetic ablation of ASM abrogated meningococcal internalization without affecting bacterial adherence. In accordance, the restricted invasiveness of a defined set of pathogenic isolates of the ST-11/ST-8 clonal complex into brain endothelial cells directly correlated with their restricted ability to induce ASM and ceramide release. In conclusion, ASM activation and ceramide release are essential for internalization of Opc-expressing meningococci into brain endothelial cells, and this segregates with invasiveness of N. meningitidis strains. Author Summary Neisseria meningitidis, an obligate human pathogen, is a causative agent of septicemia and meningitis worldwide. Meningococcal infection manifests in a variety of forms, including meningitis, meningococcemia with meningitis or meningococcemia without obvious meningitis. The interaction of N. meningitidis with human cells lining the blood vessels of the blood-cerebrospinal fluid barrier is a prerequisite for the development of meningitis. As a major pathogenicity factor, the meningococcal outer membrane protein Opc enhances bacterial entry into brain endothelial cells, however, mechanisms underlying trapping of receptors and signaling molecules following this interaction remained elusive. We now show that Opc-expressing meningococci activate acid sphingomyelinase (ASM) in brain endothelial cells, which hydrolyses sphingomyelin to cause ceramide release and formation of extended ceramide-enriched membrane platforms wherein ErbB2, an important receptor involved in bacterial uptake, clusters. Mechanistically, ASM activation relied on binding of N. meningitidis to its attachment receptor, HSPG, followed by activation of PC-PLC. Meningococcal isolates of the ST-11 clonal complex, which are reported to be more likely to cause severe sepsis, but rarely meningitis, barely invaded brain endothelial cells and revealed a highly restricted ability to induce ASM and ceramide release. Thus, our results unravel a differential activation of the ASM/ceramide system by the species N. meningitidis determining its invasiveness into brain endothelial cells.},
  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{BeyersdorfWernerWolfetal.2011,
  author    = {Beyersdorf, Niklas and Werner, Sandra and Wolf, Nelli and Herrmann, Thomas and Kerkau, Thomas},
  title     = {Characterization of a New Mouse Model for Peripheral T Cell Lymphoma in Humans},
  series = {PLoS One},
  volume    = {6},
  journal   = {PLoS One},
  number    = {12},
  doi       = {10.1371/journal.pone.0028546},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137946},
  pages     = {e28546},
  year      = {2011},
  abstract  = {Peripheral T cell lymphomas (PTCLs) are associated with a poor prognosis due to often advanced disease at the time of diagnosis and due to a lack of efficient therapeutic options. Therefore, appropriate animal models of PTCL are vital to improve clinical management of this disease. Here, we describe a monoclonal CD8\(^+\) CD4\(^-\) αβ T cell receptor Vβ2\(^+\) CD28\(^+\) T cell lymphoma line, termed T8-28. T8-28 cells were isolated from an un-manipulated adult BALB/c mouse housed under standard pathogen-free conditions. T8-28 cells induced terminal malignancy upon adoptive transfer into syngeneic BALB/c mice. Despite intracellular expression of the cytotoxic T cell differentiation marker granzyme B, T8-28 cells appeared to be defective with respect to cytotoxic activity as read-out in vitro. Among the protocols tested, only addition of interleukin 2 in vitro could partially compensate for the in vivo micro-milieu in promoting growth of the T8-28 lymphoma cells.},
  language  = {en}
}