A single-dose mRNA vaccine provides a long-term protection for hACE2 transgenic mice from SARS-CoV-2
February 3, 2021
Qingrui Huang, Kai Ji, Siyu Tian, Fengze Wang, Baoying Huang, Zhou Tong, Shuguang Tan, Junfeng Hao, Qihui Wang, Wenjie Tan, George F. Gao & Jinghua Yan.
While the two-dose SARS-CoV-2 mRNA vaccines have been the focus of most vaccine research, there have been concerns about their short-lived protection against the COVID-19 virus. Huang et al. developed and tested their own single-dose mRNA vaccine, mRNA-RBD, on groups of transgenic mice, using polycytidylic acid (poly(C)) RNA as a placebo control. Their goal was to address the questionable lasting power of the current vaccines by evaluating the duration of the neutralizing antibody response following immunization with their RBD-mRNA vaccine. Groups of female mice were injected with 15 micrograms of either the mRNA vaccine or the poly(C) control; half the group was euthanized at 8 weeks, and the other half was tested periodically to determine their humoral immune response. Their results demonstrated that for more than 6 months following inoculation, there were high levels of the protective antibodies present. This data indicated that their RBD-encoding mRNA vaccine was successful at providing long-term protection. However, the paper indicated that further studies are necessary to investigate the involvement of memory B cells in the vaccine response.
Huang Q, Ji K, Tian S, et al. A single-dose mRNA vaccine provides a long-term protection for hACE2 transgenic mice from SARS-CoV-2. Nat Commun. 2021; 12: 776.