The self-assembled nanoparticle-based trimeric RBD mRNA vaccine elicits robust and durable protective immunity against SARS-CoV-2 in mice

Signal Transduct Target Ther. 2021 Sep 9;6(1):340. doi: 10.1038/s41392-021-00750-w.

Abstract

As COVID-19 continues to spread rapidly worldwide and variants continue to emerge, the development and deployment of safe and effective vaccines are urgently needed. Here, we developed an mRNA vaccine based on the trimeric receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein fused to ferritin-formed nanoparticles (TF-RBD). Compared to the trimeric form of the RBD mRNA vaccine (T-RBD), TF-RBD delivered intramuscularly elicited robust and durable humoral immunity as well as a Th1-biased cellular response. After further challenge with live SARS-CoV-2, immunization with a two-shot low-dose regimen of TF-RBD provided adequate protection in hACE2-transduced mice. In addition, the mRNA template of TF-RBD was easily and quickly engineered into a variant vaccine to address SARS-CoV-2 mutations. The TF-RBD multivalent vaccine produced broad-spectrum neutralizing antibodies against Alpha (B.1.1.7) and Beta (B.1.351) variants. This mRNA vaccine based on the encoded self-assembled nanoparticle-based trimer RBD provides a reference for the design of mRNA vaccines targeting SARS-CoV-2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • COVID-19 / immunology
  • COVID-19 / pathology
  • COVID-19 / prevention & control*
  • COVID-19 Vaccines* / chemistry
  • COVID-19 Vaccines* / pharmacology
  • Chlorocebus aethiops
  • Female
  • HEK293 Cells
  • Humans
  • Mice
  • Mice, Transgenic
  • Nanoparticles* / chemistry
  • Nanoparticles* / therapeutic use
  • SARS-CoV-2 / immunology*
  • Th1 Cells / immunology
  • Th1 Cells / pathology
  • Vaccines, Synthetic* / chemistry
  • Vaccines, Synthetic* / immunology
  • Vero Cells
  • mRNA Vaccines

Substances

  • COVID-19 Vaccines
  • Vaccines, Synthetic