Two new nanoparticle vaccines for SARS-CoV-2, the virus that causes COVID-19, can elicit potent neutralizing antibodies and cellular immune responses in animals, sources with the Guangzhou-based Sun Yat-sen University said Friday.
The university researchers formulated two nanoparticle vaccines based on the receptor binding domain and heptad repeat of the SARS-CoV-2. They could induce a high level of antibodies against COVID-19 in mice and rhesus macaques, presenting a promising vaccination approach against the virus.
The results of the animal tests were published this week in the international journal Immunity.
Lead researcher Zhang Hui said the nanoparticle vaccines were generated by conjugating multi antigenic recombinant proteins to 24-mer nanoparticles that tend to generate stronger immune responses compared with the monomers used in conventional vaccines.
The nanoparticle vaccines were potentially safe and did not cause severe side effects such as organ damage in mice. Besides, no antibody-dependent enhancement of infection was detected in the experiment, according to the study.
"We made 161 trial-and-error attempts over three months before the vaccine's effectiveness and safety were validated in animals," Zhang said.
The vaccines are being applied for clinical approval from the National Medical Products Administration.
"Strengthening vaccine research and development is the fundamental solution to eliminate public health threats," Zhang added.