Proteome based analysis of circulating SARS-CoV-2 variants: approach to a universal vaccine candidate.

The discovery of the first infectious variant in Wuhan, China, in December 2019, has posed concerns over global health due to the spread of COVID-19 and subsequent variants. While the majority of patients experience flu-like symptoms such as cold and fever, a small percentage, particularly those with compromised immune systems, progress from mild illness to fatality. COVID-19 is caused by a RNA virus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our approach involved utilizing immunoinformatic to identify vaccine candidates with multiple epitopes and ligand-binding regions in reported SARS-CoV-2 variants. Through analysis of the spike glycoprotein, we identified dominant epitopes for T-cells and B-cells, resulting in a vaccine construct containing two helper T-cell epitopes, six cytotoxic T-cell epitopes, and four linear B-cell epitopes. Prior to conjugation with adjuvants and linkers, all epitopes were evaluated for antigenicity, toxicity, and allergenicity. Additionally, we assessed the vaccine Toll-Like Receptors complex (2, 3, and 4). The vaccine construct demonstrated antigenicity, non-toxicity, and non-allergenicity, thereby enabling the host to generate antibodies with favorable physicochemical characteristics. Furthermore, the 3D structure of the B-cell construct exhibited a ProSA-web z-score plot with a value of -1.71, indicating the reliability of the designed structure. The Ramachandran plot analysis revealed that 99.6% of the amino acid residues in the vaccine subunit were located in the high favored observation region, further establishing its strong candidacy as a vaccination option.

Immunoinformatics design of multi-epitope peptide for the diagnosis of Schistosoma haematobium infection.

Schistosoma haematobium has been identified as a significant cause of urogenital disease, as well as a risk factor for bladder cancer and HIV/AIDS. The parasites are obtained trans-dermally by swimming or wading in contaminated freshwater, and they are also transmitted to humans by freshwater snails. The organisms infect the vasculature of the gastrointestinal or genitourinary tracts. Worms live in blood vessels and lay eggs that become embedded in the bladder wall, causing chronic immune-mediated disease and squamous cell carcinoma growth. The primary goal of this research is to predict and design a novel synthetic protein containing multiple immunodominant B cell epitopes using three schistosome proteins: XP-012801068.2, XP-012801892.2, and XP-012793835.2 softwares were used to analyze the proteins' primary, secondary, and tertiary structures (BepiPred, BcPred).The B cell construct was then evaluated using I-TASSER server, and physicochemical properties, as well as homology modeling of the 3 D structure of the protein, was obtained. In silico analyses revealed regions with high immunogenicity. For XP-012801068.2, three epitopes are found between residues 292-334, 3-22, and 314-333; for XP-012801892.2, three epitopes are found in the residues 184-236, 81-100, and 329-348 for XP-012793835.2, four epitopes are found in the residues 185-222, 469-512, 649-713, and 338-357. The construct's has an average length of 308 bp, instability index of 49.96, theoretical PI of 4.2 and a C score -1.59. Furthermore, these parameters analyzed reveals that the constructed multi-epitope peptide has the potential to provide a theoretical basis for the development of a Schistosoma haematobium diagnostic kit.Communicated by Ramaswamy H. Sarma.