Development of an innovative recombinant protein vaccine against Aeromonas veronii in European seabass using "omics" technologies (AeroVeroVacc)
Lead Research Organisation:
MOREDUN RESEARCH INSTITUTE
Department Name: Vaccines and Diagnostics
Abstract
Disease within aquaculture systems has led to significant economic and production losses and is one of the main barriers to expanding sustainable aquaculture. Vaccination is widely accepted as an effective strategy to combat pathogenic diseases in aquaculture and a valuable alternative to antibiotics. An emerging bacterial infection caused by Aeromonas veronii has been the cause of significant mortalities in seabass farms in the Aegean Sea. Screening for novel virulence factors in vivo may be one approach for identifying potential vaccine candidates for vaccine development against Aeromonas veronii. A novel immuno-screening
technique, in vivo induced antigen technology (IVIAT), a method that relies on antibodies adsorbed against in vitro cultures of the pathogen, is used to identify immunogenic proteins on bacteria exclusively expressed in vivo during infection. This study will utilise cutting-edge technologies to identify genes specifically expressed or upregulated in vivo within the host. In vivo induced (IVI) proteins common to the three clades of A. veronii affecting European seabass will be selected to design a universal recombinant protein vaccine for A. veronii infections affecting European seabass in the Mediterranean. The project's multidisciplinary nature is strong, involving a combination of microbiology, fish immunology, molecular biology, fish vaccinology, fish health, and aquaculture.
This interdisciplinarity approach is necessary to fulfil the overarching aim of delivering a universal recombinant protein vaccine for A. veronii affecting European seabass. Results emerging from the project will help find the chief proteins or genes that affect the virulence of the bacteria and their functions and relationships, as well as ultimately identify new virulence factors, especially for those pathogens that are antigenically diverse. This project is in line with the EU strategy for the sustainable development of aquaculture.
technique, in vivo induced antigen technology (IVIAT), a method that relies on antibodies adsorbed against in vitro cultures of the pathogen, is used to identify immunogenic proteins on bacteria exclusively expressed in vivo during infection. This study will utilise cutting-edge technologies to identify genes specifically expressed or upregulated in vivo within the host. In vivo induced (IVI) proteins common to the three clades of A. veronii affecting European seabass will be selected to design a universal recombinant protein vaccine for A. veronii infections affecting European seabass in the Mediterranean. The project's multidisciplinary nature is strong, involving a combination of microbiology, fish immunology, molecular biology, fish vaccinology, fish health, and aquaculture.
This interdisciplinarity approach is necessary to fulfil the overarching aim of delivering a universal recombinant protein vaccine for A. veronii affecting European seabass. Results emerging from the project will help find the chief proteins or genes that affect the virulence of the bacteria and their functions and relationships, as well as ultimately identify new virulence factors, especially for those pathogens that are antigenically diverse. This project is in line with the EU strategy for the sustainable development of aquaculture.
| Description | Collaboration with Functional Genomics Centre of Zurich for proteomic and transcriptomic analysis of Aeromonas veronii |
| Organisation | University of Zurich |
| Department | Functional Genomics Centre Zurich |
| Country | Switzerland |
| Sector | Academic/University |
| PI Contribution | We are collaborating with the Functional Genomic Centre of Zurich on the sequencing of Aeromonas veronii samples collected from infected European seabass, as part of the joint work we described with collaborators HCMR. In addition to spleen samples obtained from these fish for proteomics and dual transcriptomics, Dr Darzi has also provided samples of outer membrane preparations from bacteria grown under iron-restricted conditions (to mimic in vivo growth) and from bacteria cultured in standard culture medium as a comparison. She has recently received the proteomic data on the outer membrane proteins and is currently analyzing this data. |
| Collaborator Contribution | The team at the Functional Genomic Centre of Zurich (FGCZ), including Dr Weihong Qi, Dr Adriana Hotz, and Dr Paolo Nanni, is collaborating on our Aeromonas veronii research. Dr. Nanni performed proteomic analysis on the outer membrane protein samples from Fatemeh's studies on iron-restricted bacterial growth, while Dr Qi provided bioinformatic support for these samples. The samples from Greece are yet to be sent to FGCZ for analysis, but Dr Hotz has been advising on the best protocols for extracting RNA for the dual transcriptomics studies (bacteria cultured in vivo together with fish's response to infection) and Fatemeh is optimising the RNA extraction protocol according to Adriana's advice. The Functional Genomic Centre of Zurich's team, including Dr. Weihong Qi, Dr. Adriana Hotz, and Dr. Paolo Nanni, is collaborating with Fatemeh Hassantabar Darzi on her Aeromonas veronii research. Dr. Nanni has performed the proteomic analysis on the outer membrane protein samples from Fatemeh's studies on iron-restricted bacterial growth. Meanwhile, Dr. Qi has provided bioinformatic support for these samples. The samples from Greece are yet to be sent for analysis, but Dr. Hotz has been advising on the best protocols for extracting RNA for the dual transcriptomics studies, ensuring that the methodologies align with the project's scientific goals. |
| Impact | Data is still being analysed. |
| Start Year | 2024 |
| Description | Collaboration with Pantelis Katharios and Adriana Triga from the Hellenic Centre for Marine Research (HCMR), Crete in Greece for the growth of Aeromonas veronii in vivo and in vitro. |
| Organisation | Hellenic Centre for Marine Research (HCMR) |
| Country | Greece |
| Sector | Private |
| PI Contribution | Dr Fatemeh Hassantabar Darzi, the Marie Curie Fellow on this project, spent six weeks at the Hellenic Centre for Marine Research (HCMR), conducting fish trials to gather bacteria cultured in vivo from fish infected with Aeromonas veronii. This trial was carried out as a collaboration between Dr Pantelis Katharios and Dr Adriana Triga from HCMR and ourselves at Moredun Research Institute (MRI). |
| Collaborator Contribution | The Hellenic Centre for Marine Research (HCMR) supplied several Aeromonas veronii strains from outbreaks affecting European seabass in Greece and Turkey for our study. Along with these isolates, they provided whole genome sequencing data, aiding in our proteomic and transcriptomic analysis. From these, two genetically distinct isolates were selected based on their WGS profiles for further examination. These selected strains were cultivated in both tryptic soy broth (TSB) in vitro and within European seabass in vivo. Dr Darzi visited HCMR for a six-week period to conduct infection trials using these two isolates. The primary objective was to collect tissue samples from both infected and control fish for proteomic and transcriptomic studies (bacterial and host response). Notably, the infected fish developed large white nodules on their spleens, loaded with bacteria, which were then harvested as examples of bacteria grown in vivo. The aim is to perform proteomics and dual transcriptomics on the bacteria from these nodules (in vivo), comparing them with those cultured in TSB (in vitro). This investigative work was carried out at the close of 2024, and the analysis of these samples is currently progressing at the Moredun Research Institute. |
| Impact | Analysis of these samples is currently ongoing in collaboration with the Functional Genomic Centre of Zurich (see collaboration with FGZC) |
| Start Year | 2024 |
| Description | Kim Thompson invited to Workshop on Identifying Priority Research Areas for Finfish Health, held at the WOAH Headquarters in Paris from 20-21 February 2025 |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Third sector organisations |
| Results and Impact | The workshop was hosted by WOAH Headquarters in partnership with the STAR-IDAZ International Research Consortium on Animal Health and the WOAH Aquatic Animal Health Standard Commission. It aimed to harness global expertise and scientific excellence by convening a panel of international fish health experts. The purpose was to identify the most critical research priorities in the field of aquatic animal diseases. Expected outcomes ? Strengthen international coordination and collaboration on aquatic animal disease research by improving trust among aquaculture scientific networks; ? Identification of the highest-priority research areas for aquatic animal diseases, in particular those that will have a direct impact on international standards; ? Shared understanding on identified research needs, increasing ownership of workshop results among key stakeholders; ? Research funders & industries representatives (STAR-IDAZ IRC Executive Committee Members) informed on research needs identified ? Enhance WOAH leadership role in bringing together relevant aquatic animal health stakeholders and STAR-IDAZ role as global animal health research network; ? Strengthen, support and more fully utilise WOAH scientific networks ? Facilitate networking and engagement of WOAH Reference centres ? Encourage and support Reference centres in addressing research gaps, specifically those to improve the international standards Output ? High level document on identified major research needs for aquatic animal diseases |
| Year(s) Of Engagement Activity | 2025 |
| URL | https://www.woah.org/en/event/advancing-aquaculture-health-research-a-collaborative-workshop/ |