@article{GeyerChalmersMacKintoshetal.2013,
  author    = {Geyer, Kathrin K. and Chalmers, Iain W. and MacKintosh, Neil and Hirst, Julie E. and Geoghegan, Rory and Badets, Mathieu and Brophy, Peter M. and Brehm, Klaus and Hoffmann, Karl F.},
  title     = {Cytosine methylation is a conserved epigenetic feature found throughout the phylum Platyhelminthes},
  series = {BMC Genomics},
  volume    = {14},
  journal   = {BMC Genomics},
  number    = {462},
  issn      = {1471-2164},
  doi       = {10.1186/1471-2164-14-462},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-121892},
  year      = {2013},
  abstract  = {Background: The phylum Platyhelminthes (flatworms) contains an important group of bilaterian organisms responsible for many debilitating and chronic infectious diseases of human and animal populations inhabiting the planet today. In addition to their biomedical and veterinary relevance, some platyhelminths are also frequently used models for understanding tissue regeneration and stem cell biology. Therefore, the molecular (genetic and epigenetic) characteristics that underlie trophic specialism, pathogenicity or developmental maturation are likely to be pivotal in our continued studies of this important metazoan group. Indeed, in contrast to earlier studies that failed to detect evidence of cytosine or adenine methylation in parasitic flatworm taxa, our laboratory has recently defined a critical role for cytosine methylation in Schistosoma mansoni oviposition, egg maturation and ovarian development. Thus, in order to identify whether this epigenetic modification features in other platyhelminth species or is a novelty of S. mansoni, we conducted a study simultaneously surveying for DNA methylation machinery components and DNA methylation marks throughout the phylum using both parasitic and non-parasitic representatives. Results: Firstly, using both S. mansoni DNA methyltransferase 2 (SmDNMT2) and methyl-CpG binding domain protein (SmMBD) as query sequences, we illustrate that essential DNA methylation machinery components are well conserved throughout the phylum. Secondly, using both molecular (methylation specific amplification polymorphism, MSAP) and immunological (enzyme-linked immunoabsorbent assay, ELISA) methodologies, we demonstrate that representative species (Echinococcus multilocularis, Protopolystoma xenopodis, Schistosoma haematobium, Schistosoma japonicum, Fasciola hepatica and Polycelis nigra) within all four platyhelminth classes (Cestoda, Monogenea, Trematoda and 'Turbellaria') contain methylated cytosines within their genome compartments. Conclusions: Collectively, these findings provide the first direct evidence for a functionally conserved and enzymatically active DNA methylation system throughout the Platyhelminthes. Defining how this epigenetic feature shapes phenotypic diversity and development within the phylum represents an exciting new area of metazoan biology.},
  language  = {en}
}
@article{BrehmKoziolKrohne2013,
  author    = {Brehm, Klaus and Koziol, Uriel and Krohne, Georg},
  title     = {Anatomy and development of the larval nervous system in Echinococcus multilocularis},
  series = {Frontiers in Zoology},
  journal   = {Frontiers in Zoology},
  doi       = {10.1186/1742-9994-10-24},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96504},
  year      = {2013},
  abstract  = {Background The metacestode larva of Echinococcus multilocularis (Cestoda: Taeniidae) develops in the liver of intermediate hosts (typically rodents, or accidentally in humans) as a labyrinth of interconnected cysts that infiltrate the host tissue, causing the disease alveolar echinococcosis. Within the cysts, protoscoleces (the infective stage for the definitive canid host) arise by asexual multiplication. These consist of a scolex similar to that of the adult, invaginated within a small posterior body. Despite the importance of alveolar echinococcosis for human health, relatively little is known about the basic biology, anatomy and development of E. multilocularis larvae, particularly with regard to their nervous system. Results We describe the existence of a subtegumental nerve net in the metacestode cysts, which is immunoreactive for acetylated tubulin-α and contains small populations of nerve cells that are labeled by antibodies raised against several invertebrate neuropeptides. However, no evidence was found for the existence of cholinergic or serotoninergic elements in the cyst wall. Muscle fibers occur without any specific arrangement in the subtegumental layer, and accumulate during the invaginations of the cyst wall that form brood capsules, where protoscoleces develop. The nervous system of the protoscolex develops independently of that of the metacestode cyst, with an antero-posterior developmental gradient. The combination of antibodies against several nervous system markers resulted in a detailed description of the protoscolex nervous system, which is remarkably complex and already similar to that of the adult worm. Conclusions We provide evidence for the first time of the existence of a nervous system in the metacestode cyst wall, which is remarkable given the lack of motility of this larval stage, and the lack of serotoninergic and cholinergic elements. We propose that it could function as a neuroendocrine system, derived from the nervous system present in the bladder tissue of other taeniids. The detailed description of the development and anatomy of the protoscolex neuromuscular system is a necessary first step toward the understanding of the developmental mechanisms operating in these peculiar larval stages.},
  language  = {en}
}
@article{NonoPletinckxLutzetal.2012,
  author    = {Nono, Justin Komguep and Pletinckx, Katrien and Lutz, Manfred B. and Brehm, Klaus},
  title     = {Excretory/Secretory-Products of Echinococcus multilocularis Larvae Induce Apoptosis and Tolerogenic Properties in Dendritic Cells In Vitro},
  series = {PLoS Neglected Tropical Diseases},
  volume    = {6},
  journal   = {PLoS Neglected Tropical Diseases},
  number    = {2},
  doi       = {10.1371/journal.pntd.0001516},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134280},
  pages     = {e1516},
  year      = {2012},
  abstract  = {Background: Alveolar echinococcosis, caused by Echinococcus multilocularis larvae, is a chronic disease associated with considerable modulation of the host immune response. Dendritic cells (DC) are key effectors in shaping the immune response and among the first cells encountered by the parasite during an infection. Although it is assumed that E. multilocularis, by excretory/secretory (E/S)-products, specifically affects DC to deviate immune responses, little information is available on the molecular nature of respective E/S-products and their mode of action. Methodology/Principal Findings: We established cultivation systems for exposing DC to live material from early (oncosphere), chronic (metacestode) and late (protoscolex) infectious stages. When co-incubated with Echinococcus primary cells, representing the invading oncosphere, or metacestode vesicles, a significant proportion of DC underwent apoptosis and the surviving DC failed to mature. In contrast, DC exposed to protoscoleces upregulated maturation markers and did not undergo apoptosis. After pre-incubation with primary cells and metacestode vesicles, DC showed a strongly impaired ability to be activated by the TLR ligand LPS, which was not observed in DC pre-treated with protoscolex E/S-products. While none of the larvae induced the secretion of pro-inflammatory IL-12p70, the production of immunosuppressive IL-10 was elevated in response to primary cell E/S-products. Finally, upon incubation with DC and naive T-cells, E/S-products from metacestode vesicles led to a significant expansion of Foxp3+ T cells in vitro. Conclusions: This is the first report on the induction of apoptosis in DC by cestode E/S-products. Our data indicate that the early infective stage of E. multilocularis is a strong inducer of tolerance in DC, which is most probably important for generating an immunosuppressive environment at an infection phase in which the parasite is highly vulnerable to host attacks. The induction of CD4+CD25+Foxp3+ T cells through metacestode E/S-products suggests that these cells fulfill an important role for parasite persistence during chronic echinococcosis.},
  language  = {en}
}
@article{BrehmHaasGoebeletal.1992,
  author    = {Brehm, Klaus and Haas, Albert and Goebel, Werner and Kreft, J{\"u}rgen},
  title     = {A gene encoding a superoxide dismutase of the facultative intracellular bacterium Listeria monocytogenes},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-60515},
  year      = {1992},
  abstract  = {A gene (Imsod) encoding superoxide dismutase (SOD; EC 1.15.1.1) of the facultative intracellular pathogen, Listeria monocytogenes, was cloned by functional complementation of an SOD-deficient Escherichia coli mutant. The nucleotide sequence was determined and the deduced amino acid (aa) sequence (202 aa) showed close similarity to manganese-containing SOD's from other organisms. Subunits of the recombinant L. monocytogenes SOD (re-SOD) and of both E. coli SODs formed enzymatically active hybrid enzymes in vivo. DNA/DNA-hybridization experiments showed that this type of recombinant re-sod gene is conserved within the genus Listeria.},
  subject      = {Biologie},
  language  = {en}
}
@article{HaasBrehmKreftetal.1991,
  author    = {Haas, Albert and Brehm, Klaus and Kreft, J{\"u}rgen and Goebel, Werner},
  title     = {Cloning, characterization, and expression in Escherichia coli of a gene encoding Listeria seeligeri catalase, a bacterial enzyme highly homologous to mammalian catalases},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-60536},
  year      = {1991},
  abstract  = {A gene coding for catalase (hydrogen-peroxide:hydrogen-peroxide oxidoreductase; EC 1.11.1.6) of the grain-positive bacterium Listeria seeligeri was cloned from a plasmid library of EcoRI-digested chromosomal DNA, with Escherichia coli DHSa as a host. The recombinant catalase was expressed in E. coli to an enzymatic activity approximately SO times that of the combined E. coli catalases. The nucleutide sequence was determined, and the deduced amino acid sequence revealed 43.2\% amino acid sequence identity between bovine liver catalase and L. seeligeri catalase. Most of the amino acid residues which are involved in catalytic activity, the formation of the active center accession channel, and heme binding in bovine liver catalase were also present in L. seeligeri catalase at the corresponding positions. The recombinant protein contained 488 amino acid residues and had a calculated molecular weight of 55,869. The predicted isoelectric point was 5.0. Enzymatic and genetic analyses showed that there is most probably a single catalase of this type in L. seeligeri. A perfect 21-bp inverted repeat, which was highly homologous to previously reported binding sequences of the Fur (ferric uptake regulon) protein of E. coli, was detected next to the putative promoter region of tbe L. seeligeri catalase gene.},
  subject      = {Biologie},
  language  = {en}
}