Dengue virus poses a significant global health challenge, particularly in tropical and subtropical regions. Despite the urgent demand for vaccines in the control of the disease, the two approved vaccines, Dengvaxia and TV003/TV005, there are current questions regarding their effectiveness due to an increased risk of antibody-dependent enhancement (ADE) and reduced protection. These challenges have underscored the need for further development of improved vaccines for Dengue Virus. This study presents a new design using an in silico approach to generate a more effective dengue vaccine. Initially, our design process began with the collection of Dengue polyprotein sequences from 10 representative countries worldwide. And then conserved fragments of viral proteins were retrieved as the bases for epitope screening. The selection of epitopes was then carried out with criteria such as antigenicity, immunogenicity, and binding affinity with MHC molecules, while the exclusion criteria were according to their allergenicity, toxicity, and potential for antibody-dependent enhancement. We then constructed a core antigen with the selected epitopes and linked the outcomes with distinct adjuvant proteins, resulting in three candidate vaccines: PSDV-1, PSDV-2, and PSDV-3. Among these, PSDV-2 was selected for further validation due to its superior physicochemical and structural properties. Extensive simulations demonstrated that PSDV-2 exhibited strong binding to pattern recognition receptors, high stability, and robust immune induction, confirming its potential as a high-quality vaccine candidate. For its recombinant expression, a plasmid was subsequently designed. Our new vaccine design offers a promising additional option for Dengue virus protection. Further experimental validations will be conducted to confirm its protective efficacy and safety.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major viral threat to swine, causing significant economic loss in the global pig farming industry. This virus includes two major genotypes, PRRSV1 and PRRSV2, both characterized by high mutation rates and genetic variability, complicating the development of a universally effective vaccine and disease control. To address this challenge, this study utilizes immunoinformatics tools to identify conserved epitopes and design a multi-epitope vaccine candidate against PRRSV based on reverse vaccinology. The complete sequences of PRRSV-encoded proteins were retrieved worldwide, and the conserved fragments were identified through the alignment of polypeptide sequences. Subsequent screening was conducted to screen epitopes for their potential to be safe and to activate B cells, HTLs (helper T cells), and CTLs (cytotoxic T cells). By conjugating the selected epitopes with distinct adjuvant proteins, three vaccine candidates were designed and termed PRRSV-vaccine (PRRSV-V-1, PRRSV-V-2, and PRRSV-V-3, respectively). Furthermore, systematic evaluations of their physicochemical properties, structural stability, binding with pattern recognition receptors, and induction of the host immune system were performed. PRRSV-V-2 had the most promising physicochemical and structural characteristics, strong binding with toll-like receptors (TLR3 and TLR8), and the most vigorous reactions to host immune responses. As the most promising candidate, the recombinant PRRSV plasmid was in silico designed for expression in Escherichia coli. Our study proposed a novel approach to PRRSV vaccine development against PRRSV, offering a promising strategy for controlling the infection across diverse PRRSV strains in swine. Despite providing significant insights into vaccine design through computational methods, the results of this study remain predictive. So, it is open for the experimental validations of the scientific community to ensure its actual immunological properties, especially the safety and efficacy.

Dengue virus is a global health problem most prevalent in tropical and subtropical regions. However, after the approval of two vaccines, Dengvaxia, TV003/TV005 of Takeda, for its prevention, problems were reported, like enhanced risks of infection or less efficiency of protection. Since then, more struggles have been in demand for the development of better vaccines. Here, we conducted a new design through an in-silico strategy. Initially, epitopes were chosen based on their antigenicity, immunogenicity, and binding affinity with MHC molecule, while excluded with allergenicity, toxicity and potential risk of antibody dependent enhancement. Subsequently, a core antigen was constructed with selected epitopes and linked with distinct adjuvant proteins to achieve three candidate vaccines, PSDV-1~3. PSDV-2 was chosen for further validation based on their advantage in physicochemical and structural properties. With a panel of simulations, this artificial protein showed tight binding with pattern recognition receptors, good stability, robust immune induction, and ultimately was confirmed as a high quality vaccine candidate. The plasmid for its recombinant expression was then designed accordingly. With our new design, one more choice was obtained for the effective protection from Dengue virus. Further experimental validations are still require to confirm it protection capacity and safety.

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a major viral threat to swine, causing a significant economic loss in the global pig farming industry. This virus includes two major genotypes, both characterized by high mutation rates and genetic variability, complicating the development of a universally effective vaccine and the control of disease consequently. To address this challenge, a novel multi-epitope-based vaccine was designed to elicit a robust and cross-protective immune response against multiple PRRSV strains. The complete sequences of PRRSV-encoded proteins were retrieved worldwide, and the conserved fragments were identified through the alignment of polypeptide sequences. Subsequent screening was conducted screened epitopes for their potential to be safe and to activate B cells, CTLs, and HTLs. By conjugating the selected epitopes with distinct adjuvant proteins, three vaccine candidates were designed and termed as PRRSV-Vaccine (PRRSV-V-1, PRRSV-V-2, and PRRSV-V-3 respectively). Furthermore, systematic evaluations of their physiochemistry properties, structural stability, binding with pattern recognition receptors, and induction of the host immune system were performed. PRRSV-V-2 was demonstrated with the most promising physicochemical and structural characteristics, strong binding with TLR3 and TLR8, and the most vigorous reactions of host immune response. As the most promising candidate, the recombinant PRRSV plasmid was in-silico designed for expression in Escherichia coli. Our study proposed a novel approach to PRRSV vaccine development against PRRSV, offering a promising strategy for controlling the infection across diverse PRRSV virus strains in swine.

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a major viral threat to swine, causing significant economic loss in global pig farming industry. The virus exists in two major genotypes, both characterized by high mutation rates and genetic variability, complicating the development of a universally effective vaccine and the control of disease consequently. To address this challenge, a novel multi-epitope-based vaccine was designed to elicit a robust and cross-protective immune response against multiple PRRSV strains. The complete sequences of PRRSV encoded proteins were retrieved worldwide, and the conserved fragments were identified through alignment of polypeptide sequences. Subsequent screening was conducted screened epitopes for their potential to be safe and to activate B cells, CTLs and HTLs. By conjugating the selected epitopes with distinct adjuvant proteins, three vaccine candidates were constructed and termed as PRRSV-Vaccine (PRRSV-V-1, PRRSV-V-2, and PRRSV-V-3 respectively). Furthermore, systematic evaluations of their physiochemistry properties, structural stability, binding with pattern recognition receptors and induction of host immune system were performed. PRRSV-V-2 was demonstrated with most promising physicochemical and structural characteristics, strong binding with TLR3 and TLR8, and most vigorous reactions of host immune response. As the most promising candidate, the recombinant PRRSV plasmid was in-silico designed for expression in Escherichia coli. Our study proposed a novel approach to PRRSV vaccine development against PRRSV, offering a promising strategy for controlling the infection across diverse PRRSV virus strains in swine.