TY  - JOUR
AB  - Outbreaks of furunculosis cause significant losses in salmonid aquaculture worldwide. With a recent rise in antimicrobial resistance, regulatory measures to minimize the use of antibiotics in animal husbandry, including aquaculture, have increased scrutiny and availability of veterinary medical products to control this disease in production facilities. In such a regulatory environment, the utility of autogenous vaccines to assist with disease prevention and control as a veterinary-guided prophylactic measure is of high interest to the producers and veterinary services alike. However, evolving concepts of epidemiological units and epidemiological links need to be considered during approval and acceptance procedures for the application of autogenous vaccines in multiple aquaculture facilities. Here, we present the results of solid-state nanopore sequencing (Oxford Nanopore Technologies, ONT) performed on 54 isolates of Aeromonas salmonicida ssp. salmonicida sampled during clinical outbreaks of furunculosis in different aquaculture facilities from Bavaria, Germany, from 2017 to 2020. All of the performed analyses (phylogeny, single nucleotide polymorphism and 3D protein modeling for major immunogenic proteins) support a high probability that all studied isolates belong to the same epidemiological unit. Simultaneously, we describe a cost/effective method of whole genome analysis with the usage of ONT as a viable strategy to study outbreaks of other pathogens in the field of aquatic veterinary medicine for the purpose of developing the best autogenous vaccine candidates applicable to multiple aquaculture establishments.
AU  - Wojnarowski, K.*
AU  - Cholewińska, P.*
AU  - Steinbauer, P.*
AU  - Lautwein, T.*
AU  - Hussein, W.*
AU  - Streb, L.-M.
AU  - Palić, D.*
C1  - 72153
C2  - 56469
TI  - Genomic analysis of Aeromonas salmonicida ssp. salmonicida isolates collected during multiple clinical outbreaks supports association with a Single epidemiological unit.
JO  - Pathogens
VL  - 13
IS  - 10
PY  - 2024
SN  - 2076-0817
ER  - 

TY  - JOUR
AB  - Influenza, a respiratory disease mainly caused by influenza A and B, viruses of the Orthomyxoviridae, is still a burden on our society's health and economic system. Influenza A viruses (IAV) circulate in mammalian and avian populations, causing seasonal outbreaks with high numbers of cases. Due to the high variability in seasonal IAV triggered by antigenic drift, annual vaccination is necessary, highlighting the need for a more broadly protective vaccine against IAV. The safety tested Modified Vaccinia virus Ankara (MVA) is licensed as a third-generation vaccine against smallpox and serves as a potent vector system for the development of new candidate vaccines against different pathogens. Here, we generated and characterized recombinant MVA candidate vaccines that deliver the highly conserved internal nucleoprotein (NP) of IAV under the transcriptional control of five newly designed chimeric poxviral promoters to further increase the immunogenic properties of the recombinant viruses (MVA-NP). Infections of avian cell cultures with the recombinant MVA-NPs demonstrated efficient synthesis of the IAV-NP which was expressed under the control of the five new promoters. Prime-boost or single shot immunizations in C57BL/6 mice readily induced circulating serum antibodies' binding to recombinant IAV-NP and the robust activation of IAV-NP-specific CD8+ T cell responses. Moreover, the MVA-NP candidate vaccines protected C57BL/6 mice against lethal respiratory infection with mouse-adapted IAV (A/Puerto Rico/8/1934/H1N1). Thus, further studies are warranted to evaluate the immunogenicity and efficacy of these recombinant MVA-NP vaccines in other IAV challenge models in more detail.
AU  - Langenmayer, M.C.*
AU  - Luelf-Averhoff, A.T.*
AU  - Marr, L.*
AU  - Jany, S.*
AU  - Freudenstein, A.*
AU  - Adam-Neumair, S.*
AU  - Tscherne, A.*
AU  - Fux, R.*
AU  - Rojas, J.J.*
AU  - Blutke, A.
AU  - Sutter, G.*
AU  - Volz, A.*
C1  - 68052
C2  - 54530
CY  - St Alban-anlage 66, Ch-4052 Basel, Switzerland
TI  - Newly designed poxviral promoters to improve immunogenicity and efficacy of MVA-NP candidate vaccines against lethal influenza virus infection in mice.
JO  - Pathogens
VL  - 12
IS  - 7
PB  - Mdpi
PY  - 2023
SN  - 2076-0817
ER  - 

TY  - JOUR
AB  - The biological control of plant pathogens is linked to the composition and activity of the plant microbiome. Plant-associated microbiomes co-evolved with land plants, leading to plant holobionts with plant-beneficial microbes but also with plant pathogens. A diverse range of plant-beneficial microbes assists plants to reach their optimal development and growth under both abiotic and biotic stress conditions. Communication within the plant holobiont plays an important role, and besides plant hormonal interactions, quorum-sensing signalling of plant-associated microbes plays a central role. Quorum-sensing (QS) autoinducers, such as N-acyl-homoserine lactones (AHL) of Gram-negative bacteria, cause a pronounced interkingdom signalling effect on plants, provoking priming processes of pathogen defence and insect pest control. However, plant pathogenic bacteria also use QS signalling to optimise their virulence; these QS activities can be controlled by quorum quenching (QQ) and quorum-sensing inhibition (QSI) approaches by accompanying microbes and also by plants. Plant growth-promoting bacteria (PGPB) have also been shown to demonstrate QQ activity. In addition, some PGPB only harbour genes for AHL receptors, so-called luxR-solo genes, which can contribute to plant growth promotion and biological control. The presence of autoinducer solo receptors may reflect ongoing microevolution processes in microbe–plant interactions. Different aspects of QS systems in bacteria–plant interactions of plant-beneficial and pathogenic bacteria will be discussed, and practical applications of bacteria with AHL-producing or-quenching activity; QS signal molecules stimulating pathogen control and plant growth promotion will also be presented.
AU  - Hartmann, A.*
AU  - Klink, S.
AU  - Rothballer, M.
C1  - 63765
C2  - 51621
CY  - St Alban-anlage 66, Ch-4052 Basel, Switzerland
TI  - Importance of N-acyl-homoserine lactone-based quorum sensing and quorum quenching in pathogen control and plant growth promotion.
JO  - Pathogens
VL  - 10
IS  - 12
PB  - Mdpi
PY  - 2021
SN  - 2076-0817
ER  - 

TY  - JOUR
AB  - For many years, brown trout (Salmo trutta fario) mortalities within the pre-alpine Isar River in Germany were reported by the Bavarian Fisheries Association (Landesfischereiverband Bayern e.V.) and local recreational anglers during August and September. Moribund fish seemed to be affected by proliferative darkening syndrome (PDS). In addition, proliferative kidney disease (PKD) caused by Tetracapsuloides bryosalmonae was discussed. To investigate this phenomenon, the present field study monitored brown trout mortalities by daily river inspection in 2017 and 2018. Moribund brown trout (n = 31) were collected and examined using histology, immunohistochemistry, qPCR, and quantitative stereology. Our investigations identified 29 (93.5%) brown trout affected by PKD. Four brown trout (12.9%) displayed combined hepatic and splenic lesions fitting the pathology of PDS. The piscine orthoreovirus 3, suspected as causative agent of PDS, was not detectable in any of the samples. Quantitative stereological analysis of the kidneys revealed a significant increase of the renal tissue volumes with interstitial inflammation and hematopoietic hyperplasia in PKD-affected fish as compared to healthy brown trout. The identified T. bryosalmonae strain was classified as part of the North American clade by phylogenetical analysis. This study highlights PKD and PDS as contributing factors to recurrent autumnal brown trout mortalities.
AU  - Arndt, D.*
AU  - Fux, R.*
AU  - Blutke, A.
AU  - Schwaiger, J.*
AU  - El-Matbouli, M.*
AU  - Sutter, G.*
AU  - Langenmayer, M.C.*
C1  - 57090
C2  - 47469
CY  - St Alban-anlage 66, Ch-4052 Basel, Switzerland
TI  - Proliferative kidney disease and proliferative darkening syndrome are linked with brown trout (Salmo trutta fario) mortalities in the pre-alpine Isar River.
JO  - Pathogens
VL  - 8
IS  - 4
PB  - Mdpi
PY  - 2019
SN  - 2076-0817
ER  -