Time filter

Source Type

Steinau an der Strasse, Germany

Gurumurthy R.K.,Max Planck Institute for Infection Biology | Maurer A.P.,Max Planck Institute for Infection Biology | Machuy N.,Max Planck Institute for Infection Biology | Hess S.,Max Planck Institute for Infection Biology | And 6 more authors.
Science Signaling | Year: 2010

Chlamydiae are obligate intracellular bacterial pathogens that have a major effect on human health. Because of their intimate association with their host, chlamydiae depend on various host cell functions for their survival. Here, we present an RNA-interference-based screen in human epithelial cells that identified 59 host factors that either positively or negatively influenced the replication of Chlamydia trachomatis (Ctr). Two factors, K-Ras and Raf-1, which are members of the canonical Ras-Raf-MEK (mitogen-activated or extracellular signal-regulated protein kinase kinase)-ERK (extracellular signal-regulated kinase) pathway, were identified as central components of signaling networks associated with hits from the screen. Depletion of Ras or Raf in HeLa cells increased pathogen growth. Mechanistic analyses revealed that ERK was activated independentlyof K-Ras and Raf-1. Infection with Ctr led to the Akt-dependent, increased phosphorylation (and inactivation) of Raf-1 atserine-259. Furthermore, phosphorylated Raf-1 relocalized from the cytoplasm to the intracellular bacterial inclusion in an Akt- and 14-3-3β-dependent manner. Together, these findings not only show that Chlamydia regulates components of an important host cell signaling pathway, but also provide mechanistic insights into how this is achieved. Copyright 2008 by Association for the Advancement of Science, 1200 New York Avenue, NW, Wa the American Association for the Advancement of Science; all rights reserved.

Bartfeld S.,Max Planck Institute for Infection Biology | Hess S.,Max Planck Institute for Infection Biology | Hess S.,Hannover Medical School | Bauer B.,Max Planck Institute for Infection Biology | And 4 more authors.
BMC Cell Biology | Year: 2010

Background: The nuclear factor-κB (NF-κB) family of transcription factors plays a role in a wide range of cellular processes including the immune response and cellular growth. In addition, deregulation of the NF-κB system has been associated with a number of disease states, including cancer. Therefore, insight into the regulation of NF-κB activation has crucial medical relevance, holding promise for novel drug target discovery. Transcription of NF-κB-induced genes is regulated by differential dynamics of single NF-κB subunits, but only a few methods are currently being applied to study dynamics. In particular, while oscillations of NF-κB activation have been observed in response to the cytokine tumor necrosis factor α (TNFα), little is known about the occurrence of oscillations in response to bacterial infections.Results: To quantitatively assess NF-κB dynamics we generated human and murine monoclonal cell lines that stably express the NF-κB subunit p65 fused to GFP. Furthermore, a high-throughput assay based on automated microscopy coupled to image analysis to quantify p65-nuclear translocation was established. Using this assay, we demonstrate a stimulus- and cell line-specific temporal control of p65 translocation, revealing, for the first time, oscillations of p65 translocation in response to bacterial infection. Oscillations were detected at the single-cell level using real-time microscopy as well as at the population level using high-throughput image analysis. In addition, mathematical modeling of NF-κB dynamics during bacterial infections predicted masking of oscillations on the population level in asynchronous activations, which was experimentally confirmed.Conclusions: Taken together, this simple and cost effective assay constitutes an integrated approach to infer the dynamics of NF-κB kinetics in single cells and cell populations. Using a single system, novel factors modulating NF-κB can be identified and analyzed, providing new possibilities for a wide range of applications from therapeutic discovery and understanding of disease to host-pathogen interactions. © 2010 Bartfeld et al; licensee BioMed Central Ltd.

A portable reader module includes a housing, a first receptacle configured to removably receive a portable device having an imager, and a second receptacle configured to removably receive a cartridge. The first receptacle includes a first optical entrance for the imager to the internal space of the housing. The second receptacle includes a second optical entrance to the internal space of the housing. A light-deflecting optical element is arranged within the internal space of the housing to define an optical path between the first optical entrance and the second optical entrance. An illuminating path for illuminating the cartridge is defined in the housing. The housing is configured to allow the internal space to be light-shielded.

Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: HEALTH.2012.2.1.2-3 | Award Amount: 3.67M | Year: 2012

The aim of CASyM is a combined large scale effort to sustainably implement Systems Medicine across Europe. For that purpose CASyM will function as a managing and coordinating platform in bringing together a critical mass of relevant European stakeholders such as Systems Biology scientists, clinicians, programme managers, industry/SMEs as well as healthcare providers and patient organizations. The goal of that initial nucleus of experts is the development of a strategy to implement the Systems Biology approach into medical practice and research within the 4 years duration of CASyM. For this purpose it is essential that the involved communities build a vision and coordinated strategy. Our joint effort gathers extensive experience in the coordination and realization of such a new, large-scale European effort, thereby providing the basis for an advanced future medicine. The output of CASyM will be a conceptual framework defining the remits, milestones, mechanisms and metrics for the implementation of Systems Medicine. The development of this framework will overcome competitive barriers and proceed to produce a European roadmap for Systems Medicine as concerted project result.

Kaba H.E.J.,Helmholtz Center for Infection Research | Maier N.,University of Potsdam | Schliebe-Ohler N.,University of Potsdam | Mayer Y.,Microdiscovery GmbH | And 5 more authors.
Journal of Microbiological Methods | Year: 2015

We selected the immunogenic cell wall ß-(1,3)-glucosyltransferase Bgl2p from Candida albicans as a target protein for the production of antibodies. We identified a unique peptide sequence in the protein and generated monoclonal anti- C. albicans Bgl2p antibodies, which bound in particular to whole C. albicans cells. albicans without pretreatment is presented. albicans cells was possible using flow cytometry. albicans from the related yeast Candida glabrata. © 2014 Elsevier B.V.

Discover hidden collaborations