Rotaviral gastroenteritis remains a major global health concern, particularly for infants and young children under five years old. Prior to the introduction of the WHO-prequalified rotavirus vaccine, rotavirus (RV) was responsible for approximately 800,000 child deaths annually in developing countries. Although vaccination efforts have reduced this number, RV still causes around 200,000 child deaths each year worldwide. The current WHO-prequalified vaccines are live attenuated and offer limited efficacy of 40–60%, with a slight risk of intussusception in young children. To overcome these limitations, we employed immunoinformatics to design a novel multi-epitope vaccine (MEV) targeting rotavirus outer capsid proteins VP4 and VP7, as well as crucial non-structural proteins NSP2 and NSP5. The RV-MEV incorporates 10 epitopes, including 4 CD8 + T-cell, 5 CD4 + T-cell, and 1 B-cell epitope, all of which are antigenic, non-allergenic, and non-toxic. These epitopes also showed potential to induce interferon-γ (IFN-γ). Molecular simulation studies confirmed stable interactions between RV-MEV and human TLR5 and integrin αvβ5 complexes. The RV-MEV was successfully cloned into a pET28a(+) vector during in-silico cloning. Immune simulation studies predict a strong immune response to the RV-MEV. Future in vitro and in vivo studies are necessary to validate the vaccine’s effectiveness in providing protection against various rotavirus strains in neonates.

The coronavirus pandemic is a major public health crisis affecting global health systems with dire socioeconomic consequences, especially in vulnerable regions such as Latin America (LATAM). There is an urgent need for a vaccine to help control contagion, reduce mortality and alleviate social costs. In this study, we propose a rational multi-epitope candidate vaccine against SARS-CoV-2. Using bioinformatics, we constructed a library of potential vaccine peptides, based on the affinity of the most common major human histocompatibility complex (HLA) I and II molecules in the LATAM population to predict immunological complexes among antigenic, non-toxic and non-allergenic peptides extracted from the conserved regions of 92 proteomes. Although HLA-C, had the greatest antigenic peptide capacity from SARS-CoV-2, HLA-B and HLA-A, could be more relevant based on COVID-19 risk of infection in LATAM countries. We also used three-dimensional structures of SARS-CoV-2 proteins to identify potential regions for antibody production. The best HLA-I and II predictions (with increased coverage in common alleles and regions evoking B lymphocyte responses) were grouped into an optimized final multi-epitope construct containing the adjuvants Beta defensin-3, TpD, and PADRE, which are recognized for invoking a safe and specific immune response. Finally, we used Molecular Dynamics to identify the multi-epitope construct which may be a stable target for TLR-4/MD-2. This would prove to be safe and provide the physicochemical requirements for conducting experimental tests around the world.

Gastrointestinal diarrhea is majorly caused by the rotavirus (RV) in the children who generally are under the age group of 5 years. WHO estimates that ∼95% of the children contract RV infection, by this age. The disease is highly contagious; notably in many cases, it is proven fatal with high mortality rates especially in the developing countries. In India alone, an estimated 145,000 yearly deaths occurs due to RV related gastrointestinal diarrhea. WHO pre-qualified vaccines that are available for RV are all live attenuated vaccines with modest efficacy range between 40 and 60%. Further, the risk of intussusceptions has been reported in some children on RV vaccination. Thus, in a quest to develop alternative candidate to overcome challenges associated with these oral vaccines, we chose immunoinformatics approach to design a multi-epitope vaccine (MEV) while targeting the outer capsid viral proteinsVP4 and VP7 of the neonatal strains of rotavirus. Interestingly, ten epitopes, that is, six CD8⁺T-cells and four CD4⁺T-cell epitopes were identified which were predicted to be antigenic, non-allergic, non-toxic and stable. These epitopes were then linked to adjuvants, linkers, and PADRE sequences to create a multi-epitope vaccine for RV. The in silico designed RV-MEV and human TLR5 complex displayed stable interactions during molecular dynamics simulations. Further, the immune simulation studies of RV-MEV corroborated that the vaccine candidate emerges as a promising immunogen. Future investigations while performing in vitro and in vivo analyses with designed RV-MEV construct are highly desirable to warrant the potential of this vaccine candidate in protective immunity against different strains of RVs infecting neonates.Communicated by Ramaswamy H. Sarma.

The coronavirus pandemic is a major public health crisis affecting global health systems with dire socioeconomic consequences, especially in vulnerable regions such as Latin America. There is an urgent need for a vaccine to help control contagion, reduce mortality and alleviate social costs. In this study, we propose a rational multi-epitope vaccine against SARS-CoV-2. Using bioinformatics, we constructed a library of potential vaccine peptides to predict immunological complexes among antigenic, non-toxic and non-allergenic peptides extracted from the conserved regions of 92 proteomes. We included the most common HLA-I and II molecules in the Latin American population. We also used three-dimensional structures of SARS-CoV-2 proteins to identify potential regions for antibody production. The best HLA-I and II predictions (with increased coverage in common alleles and regions evoking B lymphocyte responses) were grouped into an optimised final construct that meets the necessary safety and physicochemical requirements for conducting experimental tests.