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Riedel, C.

Publications and source records attributed to Riedel, C..

7 recordsLinked to original sources

Whole genome screening defines a key role of autophagy in resistance of bovine cells to BVDV infection

Bovine viral diarrhea virus (BVDV, genus Pestivirus, family Flaviviridae) is a notifiable pathogen of cattle which significantly impacts animal health, welfare, and the economy. Several cellular factors important for BVDV infection, such as Jiv, CD46 and ADAM17, have already been identified providing new targets development of effective defense strategies. However, our knowledge about BVDV host factor requirements remains limited, as no genome-wide studies of BVDV host resistance factors were performed to date, in part due to lack of accessible whole genome libraries. To close this gap, we have designed a novel bovine whole genome knockout library and successfully used it to identify a set of BVDV host resistance factors. The validity of our approach is highlighted by the strong selection of cells with inactivated ADAM17 and TMEM41B, which have both been described to be of pivotal importance for BVDV infection. In addition, guides targeting VMP1, recently identified as an important factor for flavivirus infection, were also significantly enriched in our screen. Furthermore, we found differential selection of several proteins essential for triggering autophagy, providing additional strong evidence of this process underlying key cellular functions involved in resistance to BVDV.

cell biology↗

Fertilization impacts microbiomes along the grassland trophic chain

Agricultural grasslands are often managed intensively, influencing soil properties and microbial communities. This can result in significant community changes and challenges to health and function at different levels along the trophic chain. This study investigates how fertilization affects microbial communities in grassland ecosystems in multiple connected trophic compartments. Shifts in microbial composition occurred in response to fertilization with effects being host-dependent and changes being more pronounced in belowground compartments. Strong interactions between trophic levels facilitated transmission of bacterial genera from soil and roots to higher trophic levels. Pig slurry- derived microbes were found in all compartments, but their low prevalence suggests an indirect effect of fertilisation, primarily due to changes in nutrient availability. Our findings emphasize the importance of considering both individual compartments and trophic interactions in ecosystems to fully understand the effects of anthropogenic disturbances on environmental and human health.

microbiology↗

Comparing machine learning models for predicting mutation status in Acute Myeloid Leukemia patients using RNA-seq data

Acute Myeloid Leukemia (AML) is a highly heterogeneous disease. The current AML classifications are based mainly on molecular markers, including cytogenetics features, fusion genes, and the presence or absence of mutations. In this study, we investigated mutation status in AML patients through RNA-seq data in link with differential gene expression. We applied seven machine learning algorithms to identify the presence or absence of NPM1, IDH1/IDH2, and FLT3-ITD mutations, reaching 95%, 93%, and 87% accuracy, respectively. In each case, the best performing models were complex models, suggesting highly complex biological processes at work behind AML.

bioinformatics↗

Axons of cortical basket cells originating from dendrites develop higher local complexity than axons emerging from basket cell somata

Neuronal differentiation is regulated by neuronal activity. Here, we analyzed dendritic and axonal growth of Basket cells and non-Basket cells using sparse transfection of channelrhodopsin-YFP and repetitive optogenetic stimulation in slice cultures of rat visual cortex. Neocortical interneurons often display axon-carrying dendrites (AcDs). We found that the AcDs of Basket cells and non-Basket cells were on average their most complex dendrite. Further, the AcD configuration had an influence on Basket cell axonal development. Axons originating from an AcD formed denser arborizations with more terminal endings within the dendritic field of the parent cell. Intriguingly, this occurred already in unstimulated Basket cells, and complexity was not increased further by optogenetic stimulation. However, optogenetic stimulation exerted a growth-promoting effect on axons emerging from Basket cell somata. The axons of non-Basket cells neither responded to the AcD configuration nor to the optogenetic stimulation. The results suggest that the formation of locally dense Basket cell plexuses is regulated by spontaneous activity. Moreover, in the AcD configuration, the AcD and the axon it carries mutually support each others growth. TeaserTextbooks usually draw cortical neurons with axons emerging from the cell body. Axons emerging from dendrites have been considered a caprice of nature until recent work demonstrated that axon-carrying dendrites are neither a rare nor a random phenomenon. Rather, this morphological configuration awards specific functional properties. Here, we discovered a morphogenetic role of the AcD configuration in developing Basket neurons which deliver axo-somatic inhibition to pyramidal neurons. Driven by spontaneous activity, AcD and the axon mutually promote each others growth such that the axon rapidly forms a denser presynaptic terminal field. Basket cells with axons from the cell body achieve the same complexity with technical assistance via an optogenetic stimulation. This way, a dendritic origin accelerates Basket cell axonal development.

neuroscience↗

Epithelial GPR35 protects from Citrobacter rodentium infection by preserving goblet cells and mucosal barrier integrity

Goblet cells secrete mucin to create a protective mucus layer against invasive bacterial infection and are therefore essential for maintaining intestinal health. However, the molecular pathways that regulate goblet cell function remain largely unknown. Although GPR35 is highly expressed in colonic epithelial cells, its importance in promoting the epithelial barrier is unclear. In this study, we show that epithelial Gpr35 plays a critical role in goblet cell function. In mice, cell type-specific deletion of Gpr35 in epithelial cells but not in macrophages results in goblet cell depletion and dysbiosis, rendering these animals more susceptible to Citrobacter rodentium infection. Mechanistically, scRNA-seq analysis indicates that signaling of epithelial Gpr35 is essential to maintain normal pyroptosis levels in goblet cells. Our work shows that the epithelial presence of Gpr35 is a critical element for the function of goblet cell-mediated symbiosis between host and microbiota.

immunology↗

Safe and effective two-in-one replicon-and-VLP minispike vaccine for COVID-19

The large SARS-CoV-2 spike (S) protein is the main target of current COVID-19 vaccine candidates but can induce non-neutralizing antibodies, which may cause vaccination-induced complications or enhancement of COVID-19 disease. Besides, encoding of a functional S in replication-competent virus vector vaccines may result in the emergence of viruses with altered or expanded tropism. Here, we have developed a safe single round rhabdovirus replicon vaccine platform for enhanced presentation of the S receptor-binding domain (RBD). Structure-guided design was employed to build a chimeric minispike comprising the globular RBD linked to a transmembrane stem-anchor sequence derived from rabies virus (RABV) glycoprotein (G). Vesicular stomatitis virus (VSV) and RABV replicons encoding the minispike not only allowed expression of the antigen at the cell surface but also incorporation into the envelope of secreted non-infectious particles, thus combining classic vector-driven antigen expression and particulate virus-like particle (VLP) presentation. A single dose of a prototype replicon vaccine, VSV{Delta}G-minispike-eGFP (G), stimulated high titers of SARS-CoV-2 neutralizing antibodies in mice, equivalent to those found in COVID-19 patients. Boost immunization with the identical replicon further enhanced neutralizing activity. These results demonstrate that rhabdovirus minispike replicons represent effective and safe alternatives to vaccination approaches using replication-competent viruses and/or the entire S antigen. HighlightsO_LISARS-CoV-2 S RBD antigen is preferred over entire S to preclude potential disease enhancing antibodies C_LIO_LIconstruction of a chimeric rhabdovirus minispike protein presenting RBD in native conformation C_LIO_LIconstruction of single round VSV and rabies virus replicon vaccines C_LIO_LIpresentation of minispike antigen on cells and on noninfectious VLPs C_LIO_LIstrong induction of SARS-CoV-2 neutralizing antibodies by the VSV replicon/VLP system in vaccinated mice C_LI

microbiology↗

Cortical network fingerprints predict deep brain stimulation outcome in dystonia

BackgroundDeep brain stimulation (DBS) is an effective evidence-based therapy for dystonia. However, no unequivocal predictors of therapy responses exist. We investigate whether patients optimally responding to DBS present distinct brain network organization and structural patterns.\n\nMethodsBased on a German multicentre cohort of eighty-two dystonia patients with segmental and generalized dystonia, who received DBS implantation in the globus pallidus internus patients were classified based on the clinical response 36 months after DBS, as superior-outcome group or moderate-outcome group, as above or below 70% motor improvement, respectively. Fifty-one patients met MRI-quality and treatment response requirements (mean age 51.3 {+/-} 13.2 years; 25 female) and were included into further analysis. From preoperative MRI we assessed cortical thickness and structural covariance, which were then fed into network analysis using graph theory. We designed a support vector machine to classify subjects for the clinical response based on group network properties and individual grey matter fingerprints.\n\nResultsThe moderate-outcome group showed cortical atrophy mainly in the sensorimotor and visuomotor areas and disturbed network topology in these regions. From all the structural integrity of the cortical mantle explained about 45% of the stimulation amplitude. Classification analyses achieved 88% of accuracy using individual grey matter atrophy patterns to predict DBS outcome.\n\nConclusionsThe analysis of cortical integrity and network properties could be developed into independent predictors to identify dystonia patients who benefit from DBS.

neuroscience↗