Research

Funding: DFG, 215.000 EUR

Project Details:
The early steps of hepatitis C virus (HCV) cell entry involve a complex interplay between the incoming virion and host cell expressed factors. Key host factors in the early phase of HCV cell entry include scavenger receptor class B member 1 (SR-BI), low-density lipoprotein receptor (LDLR) and CD81. Work from the previous funding period has revealed how genetic variation in one host factor, the high-density lipoprotein (HDL) receptor SR-BI, can modulate HCV infection, while highlighting at the same time that to fully understand the mechanisms of early HCV-cell interactions a broader view of the host cell molecules involved is required. In particular, others and we demonstrated that HCV host factors interact with each other and with cholesterol and this critically determines susceptibility. Moreover, we have identified CD81-binding partners calpain-5 (CAPN5) and casitas B-lineage lymphoma proto-oncogene b (CBLB) as novel modulators of HCV entry.
The proposed project for the next funding period has the overarching goal to better characterize how the host factors involved in the early phase of HCV entry interact with the virus and each other, and how these interactions are modulated by genetic and pharmacological factors. The project has four parts: (1) We will evaluate coding SR-BI and CD81 variants in a LDLR/SR-BI negative or - respectively - CD81 negative context for their effect on the HCV replication cycle and especially the early phase of cell entry in vitro. (2) We will determine how selected CD81 variants influence the interaction between CD81 and SR-BI and to what extent this mechanistically explains cell entry phenotypes. Here we will cooperate with project A6 (Pietschmann) which focusesl conversely on variation in SR-BI and membrane cholesterol content. (3) We will investigate how statins and other lipid lowering drugs including the new and highly potent monoclonal antibodies directed at proprotein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of LDLR subcellular localization and function, impact HCV infection. Specifically, we will address the impact on the expression level of SR-BI, LDLR and CD81 and on membrane and cellular cholesterol content of hepatocytes as well as the impact of statin therapy on viral load and hepatic inflammation in patients with chronic hepatitis C. (4) Finally, we will extend our analysis to newly identified CD81 interaction partners CAPN5 and CBLB and their role in HCV cell entry and receptor complex regulation beginning with the generation of human variants to probe whether they impact CD81 and SR-BI interactions as well as HCV infection. Taken together, this work holds the promise of a deeper understanding of the mechanistic role of established and newly discovered HCV entry factors during the early phase of HCV cell entry, its modulation by host genetic variants and non-genetic host factors such as exposure to lipid metabolism-modulating drugs and thus of interindividual variability in the course of chronic hepatitis C.

Cooperation Partners:

Prof. Dr. Thomas von Hahn

Klinik für Gastroenterologie, Hepatologie und Endokrinologie und Institut für Molekularbiologie - Medizinische Hochschule Hannover

Funding: DFG Sonderforschungsbereich 900 "Mirkobielle Persistenz und seine Kontrolle", 215.000 EUR

Project Details:
The early steps of hepatitis C virus (HCV) cell entry involve a complex interplay between the incoming virion and host cell expressed factors. Key host factors in the early phase of HCV cell entry include scavenger receptor class B member 1 (SR-BI), low-density lipoprotein receptor (LDLR) and CD81. Work from the previous funding period has revealed how genetic variation in one host factor, the high-density lipoprotein (HDL) receptor SR-BI, can modulate HCV infection, while highlighting at the same time that to fully understand the mechanisms of early HCV-cell interactions a broader view of the host cell molecules involved is required. In particular, others and we demonstrated that HCV host factors interact with each other and with cholesterol and this critically determines susceptibility. Moreover, we have identified CD81-binding partners calpain-5 (CAPN5) and casitas B-lineage lymphoma proto-oncogene b (CBLB) as novel modulators of HCV entry.
The proposed project for the next funding period has the overarching goal to better characterize how the host factors involved in the early phase of HCV entry interact with the virus and each other, and how these interactions are modulated by genetic and pharmacological factors. The project has four parts: (1) We will evaluate coding SR-BI and CD81 variants in a LDLR/SR-BI negative or - respectively - CD81 negative context for their effect on the HCV replication cycle and especially the early phase of cell entry in vitro. (2) We will determine how selected CD81 variants influence the interaction between CD81 and SR-BI and to what extent this mechanistically explains cell entry phenotypes. Here we will cooperate with project A6 (Pietschmann) which focusesl conversely on variation in SR-BI and membrane cholesterol content. (3) We will investigate how statins and other lipid lowering drugs including the new and highly potent monoclonal antibodies directed at proprotein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of LDLR subcellular localization and function, impact HCV infection. Specifically, we will address the impact on the expression level of SR-BI, LDLR and CD81 and on membrane and cellular cholesterol content of hepatocytes as well as the impact of statin therapy on viral load and hepatic inflammation in patients with chronic hepatitis C. (4) Finally, we will extend our analysis to newly identified CD81 interaction partners CAPN5 and CBLB and their role in HCV cell entry and receptor complex regulation beginning with the generation of human variants to probe whether they impact CD81 and SR-BI interactions as well as HCV infection. Taken together, this work holds the promise of a deeper understanding of the mechanistic role of established and newly discovered HCV entry factors during the early phase of HCV cell entry, its modulation by host genetic variants and non-genetic host factors such as exposure to lipid metabolism-modulating drugs and thus of interindividual variability in the course of chronic hepatitis C.

Results:

https://www.sfb900.de/en/

Cooperation Partners:

Prof. Dr. Thomas von Hahn, Klinik für Gastroenterologie, Hepatologie und Endokrinologie und Institut für Molekularbiologie - Medizinische Hochschule Hannover

Funding: Bundesministerium für Ernährung und Landwirtschaft, 682.563 EUR

Project Details:
Unter standardisierten Versuchsbedingungen mit Einzeltierhaltung werden Akzeptanz und Verdaulichkeit sowie Auswirkungen auf die Magen-Darm-Gesundheit junger Mastschweine geprüft, in deren Mischfutter die Komponente Weizen (ca. 70 %) in zunehmenden Anteilen durch Roggen ersetzt wurde. Damit wird eine vergleichende Bewertung der beiden Schwergetreidearten in der Mastschweinefütterung ermöglicht.

Cooperation Partners:

Institut für Tierernährung, Freie Universität Berlin

Institut für Tierernährung, Universität Bonn

KWS LOCHOW GmbH, Bergen/Wohlde

Funding: Landwirtschaftliche Rentenbank, 234.673 EUR

Project Details:
The aim of this project is to develop a concept that enables the implementation of general and specific hygiene measures in mobile houses for laying hens. This concept should take into account both the current epidemic hygiene regulations and animal and environmental protection.

Cooperation Partners:

Hochschule Osnabrück

Weiland Stallbau GmbH & Co. KG

Landwirtschaftskammer Niedersachsen

Landwirtschaftskammer Nordrhein-Westfalen

Funding: Ministerium für Energiewende, Landwirtschaft, Umwelt, Natur und Digitalisierung des Landes Schleswig Holstein., 10.000 EUR

Project Details:
Dieses Projekt hat zum Ziel, geeignete Tötungsmethoden für Ferkel unter 30 kg, bei denen aus Tierschutzgründen eine Tötung erforderlich ist, hinsichtlich ihres praktischen Einsatzes im Betrieb zu bewerten.

Funding: Europäische Innovationspartnerschaft "Produktivität und Nachhaltigkeit in der Landwirtschaft" (EIP Agri) über Kompetenzzentrum Ökolandbau Nds. GmbH, 101.364 EUR

Project Details:
Turkey farming plays an essential role in the production of poultry meat in Germany. The animals are mainly kept on very specialised farms, as the animals make high demands on feed and management. The aim of this project is to cross a robust turkey from genetics and old breeds available on the market. The animals should be healthy, hardy and suitable for keeping under extensive conditions, e.g. also on mixed farms. An essential aspect for the development of the animals is the rearing. In the rearing of turkey chicks, it is currently common practice to incubate eggs artificially. After hatching, the chicks are usually kept in larger groups without the presence of an adult animal or a mother hen. In this project, the conventional hand rearing will be compared with a mother-led rearing, in particular the behaviour of the animals will be investigated with regard to stress resistance, activity, foraging behaviour, fearfulness and social behaviour.

Cooperation Partners:

Kompetenzzentrum Ökolandbau Niedersachsen GmbH, Putenzucht Klein Süstedt i. G., Farmpark-Consult, Bauckhof Fleischmanufaktur GmbH, Öko-Beratungsgesellschaft mbH - Naturland Fachberatung, Bäuerliche Gesellschaft - Demeter im Norden e. V., Ulrike Hoffmeister & Dorothee Hoenig GbR, Praxisbetriebe

Funding: DFG, 449.000 EUR

Project Details:
In this research project, the effects of Ascaris suum infections in pigs on the intestinal transport of nutrients will be investigated. This will be achieved by in vitro measurements on intact epithelium via the electrophysiological response after mucosal addition of nutrients, via flux studies using radiolabelled substrates and via uptake studies in membrane vesicles of the luminal and basolateral membrane of enterocytes. These functional studies are complemented by molecular biology studies on the expression of the transport systems (quantitative RT-PCR, Western blot and immunohistochemistry).

Results:

Koehler, S., Springer, A., Issel, N., Klinger, S., Wendt, M., Breves, G., Strube, C. (2023) Effects of adult Ascaris suum and their antigens (total and trans-cuticular excretory-secretory antigen, cuticular somatic antigen) on intestinal nutrient transport in vivo. Parasitology 150, 78-87

 

Koehler, S., Springer, A., Issel, N., Klinger, S., Wendt, M., Breves, G., Strube, C. (2021) Ascaris suum nutrient uptake and metabolic release, and modulation of host intestinal nutrient transport by excretory-secretory and cuticle antigens in vitro. Pathogens 10, 1419

 

Koehler, S., Springer, A., Issel, N., Klinger, S., Strube, C., Breves, G. (2021) Changes in porcine nutrient transport physiology in response to Ascaris suum infection. Parasite & Vectors 14, 533

Funding: Alexander von Humboldt Stiftung AvH, 5.000.000 EUR

Project Details:
Immunvirologische Forschung

Funding: NIH, 318.177 EUR

Project Details:
To achieve a comprehensive mapping of the detailed autonomic, sensory and intrinsic innervation of the colon we have brought together a multidisciplinary team of world experts who have developed breakthrough methodological approaches to assess intrinsic and extrinsic innervation as well as functional circuitry. These recent advanced technologies include the use of tissue clearing (CLARITY), optogenetics, viral tracing, and a miniaturized microelectrode array device capable of a wide range of stimulation parameters, high-resolution microscopy and fiber-optic manometry catheter, as well as laser capture microdissection combined with NanoString nCounter techniques to map the molecular profiling of enteric neurons. These approaches will be applied to define molecular identity of ENS neurons, functional connectivity, detailed autonomic and sensory neuroanatomy, identification of ENS neurons projecting to target colonic cells and influence of different type of electrical stimulation on colonic function (secretion, permeability, motility, afferent nerve modulation). This will provide the foundation of the physiological mechanisms regulating the large intestine and the basis for a strategic development of efficacious treatment for the many intractable colonic disorders.

Cooperation Partners:

Flinders University (AU), University of California Los Angeles (USA), University of Nevada School of Medicine (USA) and Technical University of Munich (DE)

Funding: EU , 330.000 EUR

Project Details:
Full proposal for the call identifier SFS-14-2016 - Research and Innovation Action
"Understanding host-pathogen-environment interactions"

The problem being addressed is the major economic losses to the pig production industry worldwide due to Streptococcus suis (S. suis). This pathogen can cause invasive disease in pigs with symptoms such as acute sepsis, meningitis, endocarditis, pneumonia and arthritis often being reported. Almost 100% of pig farms world-wide have carrier animals (based on consultation with national farming associations veterinary practitioners and scientific researchers). S. suis is also frequently associated with porcine respiratory disease complex which is one of the major causes of mortality in pigs. In polymicrobial respiratory infections S. suis is considered as an opportunist invader and the interactions with other pathogens and the effects on the host?s immune system are not well understood. S. suis is also a zoonotic pathogen and human infections worldwide have increased significantly in the past years, with most cases originating in Southeast Asia . Currently, no efficacious, cross-protective vaccines exist for S. suis and resistance to macrolides, lincosamides, tetracyclines, and sulphonamides has been reported for up to 85% of S. suis isolates in many countries.S. suis is reported to be the most serious pathogen in piglets between the ages of 4 and 12 weeks and a leading cause of mortality in suckling pigs. Reports describing difficulty in disease control and management, especially "failure of bacterin vaccines" are common. Apart from economic losses due to mortality, S. suis infections depress both food conversion efficiency and daily life weight gain, thereby increasing unit production costs. Control is a priority target for the pig production and animal health industry due to the lack of cross-protective vaccines, increasing antibiotic resistance and endemic carriage in pig herds worldwide. Furthermore, there is recent concern about the emergence of hyper-virulent strains able to cause more rapid and severe infections of pigs and humans. The goal of PIGSs is to increase our understanding of the host-pathogen-environment interactions in S. suis infections in pigs, and thereby strengthening the evidence base for new innovations and effective prevention and control strategies. These include policy advice to stakeholders (e.g. farming practices), new diagnostics for virulent strains, subunit protein vaccines and other interventions to manipulate the host's protective microbiota and natural defense/immunity.

Results:

https://onlinelibrary.wiley.com/doi/10.1002/mbo3.1234; https://www.nature.com/articles/s41598-022-18227-3; https://www.mdpi.com/2076-2607/9/2/366; https://www.mdpi.com/2076-0817/13/1/4

Cooperation Partners:

Jerry Wells (NL), Koordinator