@article{DixCzakaiSpringeretal.2016, author = {Dix, Andreas and Czakai, Kristin and Springer, Jan and Fliesser, Mirjam and Bonin, Michael and Guthke, Reinhard and Schmitt, Anna L. and Einsele, Hermann and Linde, J{\"o}rg and L{\"o}ffler, J{\"u}rgen}, title = {Genome-Wide Expression Profiling Reveals S100B as Biomarker for Invasive Aspergillosis}, series = {Frontiers in Microbiology}, journal = {Frontiers in Microbiology}, number = {7}, doi = {10.3389/fmicb.2016.00320}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-165386}, pages = {320}, year = {2016}, abstract = {Invasive aspergillosis (IA) is a devastating opportunistic infection and its treatment constitutes a considerable burden for the health care system. Immunocompromised patients are at an increased risk for IA, which is mainly caused by the species Aspergillus fumigatus. An early and reliable diagnosis is required to initiate the appropriate antifungal therapy. However, diagnostic sensitivity and accuracy still needs to be improved, which can be achieved at least partly by the definition of new biomarkers. Besides the direct detection of the pathogen by the current diagnostic methods, the analysis of the host response is a promising strategy toward this aim. Following this approach, we sought to identify new biomarkers for IA. For this purpose, we analyzed gene expression profiles of hematological patients and compared profiles of patients suffering from IA with non-IA patients. Based on microarray data, we applied a comprehensive feature selection using a random forest classifier. We identified the transcript coding for the S100 calcium-binding protein B (S100B) as a potential new biomarker for the diagnosis of IA. Considering the expression of this gene, we were able to classify samples from patients with IA with 82.3\% sensitivity and 74.6\% specificity. Moreover, we validated the expression of S100B in a real-time reverse transcription polymerase chain reaction (RT-PCR) assay and we also found a down-regulation of S100B in A. fumigatus stimulated DCs. An influence on the IL1B and CXCL1 downstream levels was demonstrated by this S100B knockdown. In conclusion, this study covers an effective feature selection revealing a key regulator of the human immune response during IA. S100B may represent an additional diagnostic marker that in combination with the established techniques may improve the accuracy of IA diagnosis.}, language = {en} } @article{HellmannLotherWursteretal.2017, author = {Hellmann, Anna-Maria and Lother, Jasmin and Wurster, Sebastian and Lutz, Manfred B. and Schmitt, Anna Lena and Morton, Charles Oliver and Eyrich, Matthias and Czakai, Kristin and Einsele, Hermann and Loeffler, Juergen}, title = {Human and Murine Innate Immune Cell Populations Display Common and Distinct Response Patterns during Their In Vitro Interaction with the Pathogenic Mold Aspergillus fumigatus}, series = {Frontiers in Immunology}, volume = {8}, journal = {Frontiers in Immunology}, number = {1716}, doi = {10.3389/fimmu.2017.01716}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-169926}, year = {2017}, abstract = {Aspergillus fumigatus is the main cause of invasive fungal infections occurring almost exclusively in immunocompromised patients. An improved understanding of the initial innate immune response is key to the development of better diagnostic tools and new treatment options. Mice are commonly used to study immune defense mechanisms during the infection of the mammalian host with A. fumigatus. However, little is known about functional differences between the human and murine immune response against this fungal pathogen. Thus, we performed a comparative functional analysis of human and murine dendritic cells (DCs), macrophages, and polymorphonuclear cells (PMNs) using standardized and reproducible working conditions, laboratory protocols, and readout assays. A. fumigatus did not provoke identical responses in murine and human immune cells but rather initiated relatively specific responses. While human DCs showed a significantly stronger upregulation of their maturation markers and major histocompatibility complex molecules and phagocytosed A. fumigatus more efficiently compared to their murine counterparts, murine PMNs and macrophages exhibited a significantly stronger release of reactive oxygen species after exposure to A. fumigatus. For all studied cell types, human and murine samples differed in their cytokine response to conidia or germ tubes of A. fumigatus. Furthermore, Dectin-1 showed inverse expression patterns on human and murine DCs after fungal stimulation. These specific differences should be carefully considered and highlight potential limitations in the transferability of murine host-pathogen interaction studies.}, language = {en} } @article{CzakaiLeonhardtDixetal.2016, author = {Czakai, Kristin and Leonhardt, Ines and Dix, Andreas and Bonin, Michael and Linde, Joerg and Einsele, Hermann and Kurzai, Oliver and Loeffler, J{\"u}rgen}, title = {Kr{\"u}ppel-like Factor 4 modulates interleukin-6 release in human dendritic cells after in vitro stimulation with Aspergillus fumigatus and Candida albicans}, series = {Scientific Reports}, volume = {6}, journal = {Scientific Reports}, doi = {10.1038/srep27990}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-181185}, year = {2016}, abstract = {Invasive fungal infections are associated with high mortality rates and are mostly caused by the opportunistic fungi Aspergillus fumigatus and Candida albicans. Immune responses against these fungi are still not fully understood. Dendritic cells (DCs) are crucial players in initiating innate and adaptive immune responses against fungal infections. The immunomodulatory effects of fungi were compared to the bacterial stimulus LPS to determine key players in the immune response to fungal infections. A genome wide study of the gene regulation of human monocyte-derived dendritic cells (DCs) confronted with A. fumigatus, C. albicans or LPS was performed and Kr{\"u}ppel-like factor 4 (KLF4) was identified as the only transcription factor that was down-regulated in DCs by both fungi but induced by stimulation with LPS. Downstream analysis demonstrated the influence of KLF4 on the interleukine-6 expression in human DCs. Furthermore, KLF4 regulation was shown to be dependent on pattern recognition receptor ligation. Therefore KLF4 was identified as a controlling element in the IL-6 immune response with a unique expression pattern comparing fungal and LPS stimulation.}, language = {en} }