Overview of research projects

Funding: BMBF, 95.000 EUR

Project Details:
Das MERS-CoV (Middle East Respiratory Syndrome Coronavirus) ist die Ursache einer schweren und oft auch tödlich verlaufenden Atemwegserkrankung beim Menschen. Da das Virus natürlicherweise im Dromedar zirkuliert, welches vor allem auf der Arabischen Halbinsel ein sehr bedeutsames Nutztier mit engen Kontakt zum Menschen ist, stellt das Virus eine große Herausforderung als zoonotisches Pathogen dar. Dromedare scheiden das Virus in großen Mengen mit Ex- und Sekreten aus, sodass eine Übertragung auf den Menschen sehr produktiv ist, wohingegen die Mensch-zu-Mensch-Übertragung weniger epidemiologisch bedeutsam ist.
Um die derartige Infektionskette zu unterbrechen und um den Menschen vor einer Infektion zu schützen, ist es demnach von Bedeutung, die Virusausscheidung des natürlichen Virusreservoirs und damit des Dromedars zu verhindern. Die hierbei vielversprechendste Methode scheint die wirksame Vakzinierung des Dromedars als natürlicher Viruswirt zu sein.
Bei dem zu untersuchenden Impfstoff handelt es sich um MVA-MERS-S. Hierbei wird das Gen des S Proteins von MERS-CoV in das Genom von MVA (Modifiziertes Vaccinia Virus Ankara) eingebaut, sodass dieses replikationsdefiziente und als sicher getestetes Vektorvirus das MERS CoV S Protein exprimiert und so voraussichtlich zu einer Immunität des Dromedars gegen MERS CoV führt.
Das Ziel des Projektes besteht darin, die Immunogenität und protektive Wirksamkeit des Impfstoffes im Dromedar zu überprüfen. Dabei wird die bestwirksamste Applikationsroute des Impfstoffes ermittelt, das Level und die Langlebigkeit der Immunantworten (inklusive T Zellen), welche aufgrund der Vakzinierung induziert werden, charakterisiert und letztlich die Fähigkeit des Impfstoffes eine Virusausscheidung zu verhindern, untersucht.

Funding: Drittmittelprojekt, gefördert durch die Fritz-Ahrberg-Stiftung., 46.000 EUR

Project Details:
The reduction of the salt content is a regularly discussed topic in recent years, which should be considered by the food processing industry, for example through a reduction or the replacement of sodium chloride with other substances such as potassium or magnesium chloride. In addition to the sensory properties that are mainly perceived by consumers, however, technological and microbiological parameters are also important. The aim of this study is therefore to produce raw sausages and cooked cured meats both with reduced sodium chloride concentrations and with the addition of potassium and magnesium chloride and to analyse both the sensory and other parameters. The aim is to show which (minimum) concentrations of sodium chloride or salt substitutes can be used to produce products that are acceptable for consumers in terms of food quality and, in particular, safety.

Funding: Deutsche Forschungsgemeinschaft (DFG), Bonn plus ein Doktorandenstipendium (HGNI, 1 Jahr, je 1300 ?), 75.850 EUR

Project Details:
CoVid-19 is characterized by infection of the airways by SARS-CoV-2. Apart from the respiratory tract, other organs are also involved, e.g. the intestinal tract. The importance of the intestinal infection is increasingly recognized. In a large proportion of pediatric patients, virus was detected in rectal swabs and virus shedding from the intestine was found even when oral swabs had become negative. Therefore, prolonged virus shedding and fecal-oral transmission have to be considered. This notion is supported by detection of the virus in wastewater.
The aim of this short project is to apply intestinal cell cultures to characterize the infection of differentiated intestinal epithelial cells by SARS-CoV-2 and thereafter intestinal orgranoids.
This in vitro infection approach will target the following aims:
1. Characterization of the replication efficiency of SARS-CoV-2 (virus yield, virus exit, virus entry, apical, basolateral).
2. Localization of the cellular receptor(s) in human intestinal Caco-2 cells
3. Investigation of the trafficking of the cellular receptor(s), determination and subsequent modulation of their mode of interaction with membrane microdomains (lipid rafts, LRs)
4. Effects of glycosylation modulators on the spike glycoprotein and its interaction with intestinal cells
5. Implication of virus infection on the trafficking and function of crucial enzymes of the intestinal physiology (APN, SI, LPH, DPP4).
This project will provide substantial information on the replication of SARS-CoV-2 in intestinal epithelial cells, evaluate its effects on the intestinal function and provide solid hypotheses on the molecular and biochemical basis for the symptoms elicited by SARS-CoV-2 infections. These hypotheses can be then examined at a later stage in intestinal organoids. Further, unravelling the biosynthetic pathway, glycosylation pattern and mode of interaction of the SARS-CoV-2 receptors and its modulation could constitute exquisite targets for potential therapy.

Project Details:
Ziel des Projektes ist das Vorkommen von Anti-Sperma-Antikörpern und Leukozyten im Samen einer Population von Warmblutzuchthengsten zu untersuchen. Weiterhin sollen die Auswirkungen von Anti-Sperma-Antikörpern und Leukozyten auf die Spermaqualität der betroffenen Hengste und die Entwicklung belegungsinduzierter Entzündungsreaktionen bei Stuten erforscht werden.

Cooperation Partners:

Niedersächsisches Landgestüt Celle

Project Details:
Ziel des Projekts ist die Ozonbegasung als alternative Behandlungsmethode zur herkömmlichen Antibiotikatherapie der bakteriellen Endometritis bei der Stute zu untersuchen. Bei festgestellter Eignung könnte die Etablierung dieser Therapiemethode den Antibiotikaeinsatz in der Fortpflanzungsmedizin beim Pferd senken.

Cooperation Partners:

Pferdeklinik Mühlen

Institut für Veterinär-Pathologie, Universität Leipzig

Funding: BMBF, 261.911 EUR

Project Details:
Inflammation and associated lung injury, such as the acute respiratory distress syndrome (ARDS) are major causes of morbidity and and mortality in COVID-19. The Nrf2 transcription factor activates a comprehensive cell-protective and anti-inflammatory program. It is known from mouse models that pharmacological activation of Nrf2 and induction of this program protects animals from LPS-induced ARDS. In a cell line-based screen for agents against COVID-19, we found 2 Nrf2 activators that prevent the cytopathic effect of SARS-CoV-2 at nontoxic doses. Therefore, the aims of the present project are,
- the establishment of infection models based on
human respiratory epithelial cells, a model for the alveolar
epithelial cell barrier, and ex vivo culture of lung explants,
- Evaluation of the importance of the endogenous Nrf2 program for
the cellular response against SARS-CoV-2, and
- Verification of the 2 identified Nrf2 activators and
identification of additional protective agents via a
comprehensive screening of known Nrf2 activators.

Cooperation Partners:

PD Dr. Frank Pessler, Helmholtz-Zentrum für Infektionsforschung, Hannover

Funding: Drittmittelprojekt, gefördert durch Bundesministerium für Bildung und Forschung., 125.591 EUR

Project Details:
In the second funding period of this sub-project within the Pac-Campylobacter consortium, it aims at combining optimized measures in a synergistic large scale arrangement for reducing Campylobacter spp., meeting the requirements of commercial broiler production and livestock farming. This approach focuses on a combined application of different measures in a "One Health"" approach along the entire food chain to reduce the public health risk effectively in a sustainable manner and provide practical support for veterinary public health authorities regarding this issue."

Results:

Poster Abstracts:

1. Bogun K, Peh E, Siekmann L, Plötz M, Kittler S; Untersuchungen zur Anwendung ausgewählter Säuren und Pflanzenextrakte sowie deren Kombination als Reduktionsmethode von Campylobacter spp. auf Hähnchenfleisch. 62. Arbeitstagung des Arbeitsgebietes Lebensmittelsicherheit und Verbraucherschutz der DVG, 25. bis 28. Oktober 2022

2. Bogun K, Peh E, Plötz M, Kittler S; Combination of a phage cocktail and an organic acid cocktail to reduce Campylobacter in broiler chickens - Examination of possible synergistic effects. 2nd German Phage Symposium, 23.-24.5.2022 Universität Hohenheim

3. Bogun K, Peh E, Siekmann L, Plötz M, Kittler S; Examination of selected organic acids and plant extracts and their combination as a reduction method against Campylobacter on chicken meat Zoonoses 2022 - International Symposium on Zoonoses Research 05.-07.10.2022 Berlin

Funding: Karl-Eibl-Stiftung (Form: Stipendium: 900?/Mo für Doktorand), 18.900 EUR

Project Details:
The aim of the first part of the dissertation project is to establish an innovative technology as a method of separating bull semen. The basis of this technology is the use of microfluidic chips. The second part of the project is to use this technology in genetically valuable breeding bulls whose ejaculates contain less than 70% forward-motility sperm. This technology could also be used to improve the quality of sex sorting of spermcells.

Results:

In this work we used samples with artificially induced damage for establishing protocols for flow cytometric analysis of sperm viability, as well as computer assisted analysis of sperm motility patterns. Moreover, we found that samples previously enriched with damaged sperm were especially useful for testing the effectiveness of different sperm selection procedures.

 

The major aim of this work was to evaluate how microfluidic chips perform in selecting high quality sperm, i.e., in comparison to other techniques such as swim-up and percoll density gradient centrifugation. In addition, we planned to test if sperm selected, using microfluidic chips exhibit better motility behavior, increased fertilization capacity in vitro, and wanted to evaluate the performance with the flow cytometric X/Y-sperm sorting.

 

Both, freshly diluted and cryopreserved sperm were tested also taking into account the variation among individuals. We determined that when using microfluidic sorting and swim-up methods, sperm recovery was low, however, sperm were of superior quality. Sperm recovery was higher after using percoll density gradient centrifugation, but this coincided with the presence of increased numbers of membrane damaged and motile sperm. In addition, the presence of a relatively high ratio of motile sperm in high quality sperm samples exhibited characteristic kinematic parameters including increased movement velocity and linearity; which was maintained when specimens were investigated in viscous media, mimicking oviductal fluid. In our hands, when compared with ordinary processing, remained that the increased sperm quality after microfluidic selection did not result an increased in vitro embryo production. Nonetheless, performing microfluidic sperm selection prior to flow cytometric sorting of X/Y-sperm appeared beneficial; since this improved initial sperm quality to required levels, reduced contents of debris and dead sperm during FACS sorting, and enabled to significantly improve sorting speed and the correctly oriented X-chromosome bearing sperm numbers in the population.

 

In conclusion, the use of microfluidic chips has great potential in reproductive medicine and veterinary assisted reproduction technologies. This is not only beneficial for any easier selection and enrichment of high quality sperm samples, which are more likely to fertilize an oocyte, but as a processing step, also for fulfilling the requirements needed for successful flow cytometric sorting of X/Y chromosome bearing sperm.

The use of microfluidic chips has great potential in reproductive medicine and veterinary assisted reproduction technologies. This is not only beneficial for any easier selection and enrichment of high quality sperm samples, which are more likely to fertilize an oocyte, but as a processing step, also for fulfilling the requirements needed for successful flow cytometric sorting of X/Y chromosome bearing sperm.

https://elib.tiho-hannover.de/receive/tiho_mods_00012249

Cooperation Partners:

Calisici, Oguz, Phytobiotics GmbH

Alkabes, Stephane, Masterrind GmbH Verden

Funding: EU Kommission (Horizon 2020), 3.034.581 EUR

Project Details:
The persistence of Actinobacillus pleuropneumoniae (App) on the tonsils facilitates the spread of the pathogen in pig populations. Microbiological-cultural detection of the pathogen from tonsils has proven to be difficult because the diverse commensal colonization by other bacteria (e.g., Streptococcus suis) often overgrows App during culturing. The use of selective media leads to higher sensitivity of bacteriological diagnostics, but nevertheless, the success rate compared to molecular biological tests (PCR) is not satisfactory.
In most cases, acute outbreaks of porcine pleuropneumonia occur in persistently infected pigs under the influence of trigger factors. In vitro, the influence of stress hormones, such as cortisol and catecholamines on the growth behavior of the pathogen will be investigated. Possibly, catecholamines and cortisol can be used under in vitro conditions to improve the growth behavior of A. pleuropneumoniae.