Vaccines from lactic yeast to combat viral diseases in chicken and cattle
Prof. Dr. Sven-Erik Behrens
Institute of Biochemistry and Biotechnology, Martin Luther University of Halle-Wittenberg
Recipient: Martin Luther University of Halle-Wittenberg
Funding: GO-Bio Phase I (01.06.2013 - 31.03.2018, 2.804.559 Euro)
Animal vaccines typically consist of inactivated or attenuated forms of the virus. A fundamental problem in many vaccination procedures is that it is often impossible to distinguish infected animals from vaccinated animals, which is of crucial importance for the breeding and trade of farm animals. Moreover, vaccine development is often a protracted process, and vaccinations in large operations are a technically complex undertaking.
Together with cooperation partner Karin Breunig, Sven-Erik Behrens and his team have created genetically modified strains of the lactic yeast Kluyveromyces lactis, which are intended to serve as new production organisms in the manufacture of vaccines. The single-celled fungus can produce viral protein molecules both rapidly and in large quantities. All that is required in the second step is to kill the yeast. To trigger the desired immune response, the inactivated cells – including the vaccine – can be administered to the animals directly under the skin (subcutaneously) or even in the feed. Another advantage offered by the technique is that the new vaccines enable a distinction between the natural contagion and the vaccine.
Behrens and his team have two poultry diseases in their sights – namely infectious bursitis and avian influenza – as well as a bovine diarrhoea that is widespread in Germany. All three infectious diseases are caused by viruses. In the first phase of GO-Bio funding, the Halle-based researchers hope to bring the already successfully tested subcutaneous vaccination to technical maturity. They will also be working on increasing the efficiency of the oral vaccination procedure. This would be of particular relevance for poultry vaccination in intensive farming operations. To achieve this, the researchers want to manipulate the genetically modified yeast strains at a molecular level, as well as optimise the cultivation and the means of administration.
Within the framework of the second GO-Bio funding phase, VEROVACCiNES GmbH now intends to further or newly develop and preclinically validate vaccines against various poultry and ruminant diseases - including "bird flu" and "bovine viral diarrhoea". The focus here is on the generation of so-called combination vaccines that are effective against several pathogen variants and can thus reduce the number of necessary vaccinations and their costs. The team also plans to test the avian flu vaccine in a first clinical field study.