Posted by In a new study, researchers found that an innovative nanoparticle vaccine candidate against SARS-CoV-2 produces levels of virus-neutralizing antibodies in mice that were 10 times higher than those recovered from COVID-19 infection. This candidate vaccine was designed by scientists from the University of Washington School of Medicine in Seattle and has been transferred to two companies for clinical development. The relevant research results were published in Cell, and the title of the paper is Elicitation of potent neutralizing antibody responses by designed protein nanoparticle vaccines for SARS-CoV-2.
Compared with the soluble SARS-CoV-2 spike protein (S protein) on which many leading COVID-19 vaccine candidates are based, this new nanoparticle vaccine candidate produces 10 times higher neutralizing antibodies in mice, even if the vaccine dose is reduced by 6 times. These data also show that the B cell response after vaccination is strong, which is essential for immune memory and lasting vaccine effect. When injected into a non-human primate, the nanoparticle vaccine produced neutralizing antibodies against many different parts of the spike protein. These researchers said that this may ensure that when variants of the virus appear, these animals can be protected from the mutant strains of the virus. The spike protein is part of the SARS-CoV-2 infection complex.
This candidate vaccine was developed by the structure-based vaccine design technology invented by Washington University School of Medicine. It is a self-assembled protein nanoparticle that displays 60 receptor binding domains of the SARS-CoV-2 spike protein in a highly immunogenic array. The molecular structure of this vaccine roughly mimics the molecular structure of this coronavirus, which may be the reason for its ability to trigger an enhanced immune response.
To combat the COVID-19 pandemic, a safe, effective, and scalable vaccine is needed. There are hundreds of COVID-19 vaccine candidates under development globally. And these research results highlight the utility of robust antigen display platforms and have launched cGMP manufacturing efforts to advance the SARS-CoV-2-RBD nanoparticle vaccine into the clinic. The researchers also hope that their nanoparticle platform may help fight this pandemic, and they believe the potency, stability, and manufacturability of this vaccine candidate differentiate it from many others under investigation.
Reference：
Walls, A. C., Fiala, B., Schäfer, A., Wrenn, S., Pham, M. N., Murphy, M., … & Navarro, M. J. (2020). Elicitation of potent neutralizing antibody responses by designed protein nanoparticle vaccines for SARS-CoV-2. Cell, 183(5), 1367-1382.