TY  - JOUR
A1  - Jahn, Martin T.
A1  - Markert, Sebastian M.
A1  - Ryu, Taewoo
A1  - Ravasi, Timothy
A1  - Stigloher, Christian
A1  - Hentschel, Ute
A1  - Moitinho-Silva, Lucas
T1  - Shedding light on cell compartmentation in the candidate phylum Poribacteria by high resolution visualisation and transcriptional profiling
JF  - Scientific Reports
N2  - Assigning functions to uncultivated environmental microorganisms continues to be a challenging endeavour. Here, we present a new microscopy protocol for fluorescence in situ hybridisation-correlative light and electron microscopy (FISH-CLEM) that enabled, to our knowledge for the first time, the identification of single cells within their complex microenvironment at electron microscopy resolution. Members of the candidate phylum Poribacteria, common and uncultivated symbionts of marine sponges, were used towards this goal. Cellular 3D reconstructions revealed bipolar, spherical granules of low electron density, which likely represent carbon reserves. Poribacterial activity profiles were retrieved from prokaryotic enriched sponge metatranscriptomes using simulation-based optimised mapping. We observed high transcriptional activity for proteins related to bacterial microcompartments (BMC) and we resolved their subcellular localisation by combining FISH-CLEM with immunohistochemistry (IHC) on ultra-thin sponge tissue sections. In terms of functional relevance, we propose that the BMC-A region may be involved in 1,2-propanediol degradation. The FISH-IHC-CLEM approach was proven an effective toolkit to combine -omics approaches with functional studies and it should be widely applicable in environmental microbiology.
KW  - high resolution visualisation
KW  - transcriptional profiling
KW  - FISH-CLEM
KW  - cell compartmentation
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167513
VL  - 6
IS  - 35860
ER  - 
TY  - JOUR
A1  - Vendelova, Emilia
A1  - Ashour, Diyaaeldin
A1  - Blank, Patrick
A1  - Erhard, Florian
A1  - Saliba, Antoine-Emmanuel
A1  - Kalinke, Ulrich
A1  - Lutz, Manfred B.
T1  - Tolerogenic transcriptional signatures of steady-state and pathogen-induced dendritic cells
JF  - Frontiers in Immunology
N2  - Dendritic cells (DCs) are key directors of tolerogenic and immunogenic immune responses. During the steady state, DCs maintain T cell tolerance to self-antigens by multiple mechanisms including inducing anergy, deletion, and Treg activity. All of these mechanisms help to prevent autoimmune diseases or other hyperreactivities. Different DC subsets contribute to pathogen recognition by expression of different subsets of pattern recognition receptors, including Toll-like receptors or C-type lectins. In addition to the triggering of immune responses in infected hosts, most pathogens have evolved mechanisms for evasion of targeted responses. One such strategy is characterized by adopting the host's T cell tolerance mechanisms. Understanding these tolerogenic mechanisms is of utmost importance for therapeutic approaches to treat immune pathologies, tumors and infections. Transcriptional profiling has developed into a potent tool for DC subset identification. Here, we review and compile pathogen-induced tolerogenic transcriptional signatures from mRNA profiling data of currently available bacterial- or helminth-induced transcriptional signatures. We compare them with signatures of tolerogenic steady-state DC subtypes to identify common and divergent strategies of pathogen induced immune evasion. Candidate molecules are discussed in detail. Our analysis provides further insights into tolerogenic DC signatures and their exploitation by different pathogens.
KW  - bacteria
KW  - helminths
KW  - immune evasion
KW  - mycobacteria
KW  - transcriptional profiling
KW  - tolerogenic dendritic cells
KW  - steady-state dendritic cells
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175636
VL  - 9
IS  - 333
ER  -