Vaccine development against Schmallenberg virus: from classical inactivated to modified-live to scaffold particle vaccines

Background Subsequent to its first detection in 2011, the insect-transmitted bunyavirus Schmallenberg virus (SBV; genus Orthobunyavirus) caused a large-scale epizootic of fetal malformation in the European ruminant population. By now, SBV established an enzootic status in Central Europe with regular wave-like re-emergence, which has prompted intensive research efforts in order to elucidate the pathogenesis and to develop countermeasures. Since different orthobunyaviruses share a very similar structural organization, SBV has become an important model virus to study orthobunyaviruses in general and for the development of vaccines. In this review article, we summarize which vaccine formulations have been tested to prevent SBV infections in livestock animals. Main In a first step, inactivated SBV candidate vaccines were developed, which efficiently protected against an experimental SBV infection. Due to the inability to differentiate infected from vaccinated animals (= DIVA capability), a series of further approaches ranging from modified live, live-vectored, subunit and DNA-mediated vaccine delivery to multimeric antigen-presentation on scaffold particles was developed and evaluated. In short, it was repeatedly demonstrated that the N-terminal half of the glycoprotein Gc, composed of the Gc head and the head-stalk, is highly immunogenic, with a superior immunogenicity of the complete head-stalk domain compared to the Gc head only. Furthermore, in all Gc protein-based vaccine candidates, immunized animals can be readily discriminated from animals infected with the field virus by the absence of antibodies against the viral N-protein. Conclusions Using SBV as a model virus, several vaccination-challenge studies in target species underscored the superior performance of antigenic domains compared to linear epitopes regarding their immunogenicity. In addition, it could be shown that holistic approaches combining immunization-challenge infection studies with structural analyses provide essential knowledge required for an improved vaccine design

Recent advances in laccase activity assays: A crucial challenge for applications on complex substrates

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From Corncob By-Product to Functional Lignins: Comparative Analysis of Alkaline and Organosolv Extraction Followed by Laccase Treatment

Corncobs, produced globally at over 200 million tons annually with 11–18% lignin content, represent an abundant and underexploited lignocellulosic resource for sustainable lignin valorization. In this study, two distinct extraction methodologies, alkaline treatment using sodium hydroxide and an organosolv process with a 50:50 ethanol/water mixture, were systematically compared for their efficiency in isolating lignin from corncobs. Both protocols achieved high yields, up to 82% for alkaline and 84% for organosolv extraction under optimized conditions. The resulting lignins displayed notable differences in chemical structure and physical properties, as revealed by spectroscopic and thermal analyses, highlighting their divergent potential for downstream applications. To evaluate the suitability of these lignins to biocatalytic upgrading, post-extraction enzymatic treatment was performed using Pycnoporus cinnabarinus laccase (EC 1.10.3.2). Significant structural modifications were observed in alkaline-extracted lignin, as determined by FTIR spectroscopy, while organosolv lignin remained largely unaltered, a difference attributed to its lower aqueous solubility at the enzyme’s optimal pH. These results demonstrate the critical impact of extraction conditions on lignin reactivity and suitability for enzymatic tailoring. This work underscores the potential for holistic corncob valorization within integrated biorefinery frameworks. Selective extraction and targeted enzymatic modification not only facilitate efficient by-product utilization but also expand the prospects for producing versatile bio-based materials, thereby advancing the transition toward a sustainable, circular bioeconomy

Effect of laccase pre-treatment on the mechanical properties of lignin-based agrocomposites reinforced with wood fibers

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Development of a modular vaccine platform for multimeric antigen display using an orthobunyavirus model

Emerging infectious diseases represent an increasing threat to human and animal health. Therefore, safe and effective vaccines that could be available within a short time frame after an outbreak are required for adequate prevention and control. Here, we developed a robust and versatile self-assembling multimeric protein scaffold particle (MPSP) vaccine platform using lumazine synthase (LS) from Aquifex aeolicus. This scaffold allowed the presentation of peptide epitopes by genetic fusion as well as the presentation of large antigens by bacterial superglue-based conjugation to the pre-assembled particle. Using the orthobunyavirus model Schmallenberg virus (SBV) we designed MPSPs presenting major immunogens of SBV and assessed their efficacy in a mouse model as well as in cattle, a target species of SBV. All prototype vaccines conferred protection from viral challenge infection and the multivalent presentation of the selected antigens on the MPSP markedly improved their immunogenicity compared to the monomeric subunits. Even a single shot vaccination protected about 80% of mice from an otherwise lethal dose of SBV. Most importantly, the MPSPs induced a virtually sterile immunity in cattle. Altogether, LS represents a promising platform for modular and rapid vaccine design.</p

Cytochrome oxidase activity in cognitive brain structures at 720 days of age.

<p>Cytochrome oxidase activity – reflecting overall metabolic activity – was quantified by histochemistry on sagittal brain sections. Data are expressed as µmol/min per g of tissue (means ± SEM) and were obtained from 3 to 4 individuals in each group.</p>*<p>Significant sex effect, <i>P</i><0.05 (ANOVA).</p