Background:The emergency of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) variants has led to COVID-19 worldwide with substantial social and economic consequences.SARS CoV-2 S-glycoproteins are involved in viral entry to human cells.They are naturally the main target of host immune responses, and most vaccine designs are based on them.SARS-CoV-2 variants are categorized as variants of...