A recombinant subunit vaccine candidate produced in plants elicits neutralizing antibodies against SARS-CoV-2 variants in macaques

• DOI: 10.3389/fpls.2022.901978
• Publication Date: 2022-09-28T14:10:28Z
• Authors: Narach Khorattana...; Kanjana Srisutthi...; Balamurugan Shanm...; Suwimon Manopwise...; Kaewta Rattanapisit; Chalisa Panapitakkul; Taratorn Kemthong; Nutchanat Suttisan; Suchinda Malaivij...; Arunee Thitithany...; Anan Jongkaewwattana; Waranyoo Phoolcha...
• Keywords: Antibody titer

Since the outbreak of coronavirus disease (COVID) pandemic in 2019, development effective vaccines to combat infection has been accelerated. With recent emergence highly transmissible severe acute respiratory syndrome 2 (SARS-CoV-2) variants concern (VOC), there are concerns regarding immune escape from vaccine-induced immunity. Hence an vaccine against VOC with a potent response is required. Our previous study confirmed that two doses plant-produced receptor-binding domain (RBD) SARS-CoV-2 fused Fc region human IgG1, namely Baiya Vax 1, showed high immunogenicity mice and monkeys. Here, we aimed evaluate three-dose intramuscular injection 1 on days 0, 21, 133 cynomolgus At 14 after immunization, blood samples were collected determine RBD-specific antibody titer, neutralizing antibody, pseudovirus titers. Immunized monkeys developed significantly levels antigen-specific antibodies compared control group. Interestingly, sera immunized also VOCs; Alpha, Beta, Gamma, Delta, Omicron. These findings demonstrate regimen elicits variants.