Generation and characterization of attenuated PEDV vaccine candidates

• Research unit: FSVO
• Project number: 1.19.07

Key words (German)

Porzine Epidemische Diarrhoe (PED), Impfstoff, lebend attenuierter Impfstoff, reverse Genetik, Coronavirus

Key words (English)

porcine epidemic diarrhea (PED), vaccine, live attenuated vaccine, reverse genetics, coronavirus

Short description (German)

Basierend auf den Ergebnissen und entwickelten Techniken des BLV-geförderten Projekts 1.15.05 (Etablierung von vorsorgenden Massnahmen für PEDV Ausbrüche) sollen attenuierte PEDV-Stämme hergestellt und charakterisiert werden. Der Ausgangsstamm wird von Boehringer Ingelheim (BI) zur Verfügung gestellt und soll am IVI attenuiert und kloniert (reverse Genetik) werden. Anschliessen werden Stocks von 3 PEDV Impfstammkandidaten mit unterschiedlichem Grad der Attenuation für in vivo Versuche hergestellt. Die Charakterisierung des Impfstoffkandidaten bezüglich Attenuation und Immunogenität wird bei Boehringer Ingelheim in Hannover durchgeführt.

Short description (English)

Based on the results and developed techniques of the BLV-funded project 1.15.05 (Establishing preparedness for PEDV outbreaks) we will generate and characterize attenuated candidate PEDV vaccine strains. The parental strain will be provided by Boehringer Ingelheim and will be attenuated and cloned (reverse genetics) at the IVI. Subseqeuntly 3 PEDV vaccine candidate strains with different degrees of attenuation will be produced for in vivo Experiments. The characterization of the candidate vaccine strains regarding attenuation and immunogenicity will be performed at Boehringer Ingelheim in Hannover.

Project aims (English)

Objective 1 (IVI): Apply the established strategy to attenuate high pathogenic PEDV strains and generate three attenuated vaccine candidates.

Objective 2 (IVI): Generate the attenuated PEDV vaccine candidates by reverse genetics and production of virus stocks for in vivo assessment

Objective 3 (BI): Assessment of attenuation and immunogenicity of PEDV vaccine candidates

Achievement of aims (English)

Several PEDV vaccine candidates have been successfully cloned using the TAR cloning in yeast. The clones have been sequence verified by NGS. Several clones have also been equipped with a reporter gene (green fluorescent protein gene) to monitor and facilitate virus replication and production. The obtained viruses will be assessed concerning their attenuation in vivo and subsequently the efficacy to protect from wild-type virus infection will be assessed

Transfer and application (German)

Several PEDV vaccine candidates have been successfully cloned using the transformation-associated recombination (TAR) cloning in yeast. The clones have been sequence verified by NGS. Several clones have also been equipped with a reporter gene (green fluorescent protein gene) to monitor and facilitate virus replication and production. The obtained viruses will be assessed concerning their attenuation in vivo and subsequently the efficacy to protect from wild-type virus infection will be assessed.

We expect that several of the produced vaccine candidates will show sufficient attenuation to move forward to assess the vaccine efficacy. The reverse genetic system to produce the vaccine candidates is versatile and can be applied to modify and adapt the vaccine. This will allow to update the vaccine in case novel strains may emerge. It is also possible to extend this approach to other coronaviruses that cause severe disease in pigs.