Science: Isolating SARS-CoV-2 neutralizing antibodies protects animals from virus attacks

On June 15, the team from the Scripps Institution of The United States published the latest findings in Science on SARS-CoV-2 neutralizing antibodies, separating the effective neutralizing antibodies (nAbs) against two epithelials on the receptor-binding domain (RBD) and different non-RBD epithelials on the hedgehog protein (S), and found that the use of nAbs could protect Syrian silos that suffer high doses of SARS-CoV-2 attacksDOI: 10.1126/science.abc7520specifically, researchers recruited 17 patients in California who had been infected with SARS-CoV-2 to collect their peripheral blood mononucleocells (PBMC) and plasmaAt the same time, heLa-ACE2 cell lines, which produce powerful and repeatable virus titrons, were developed, and the binding of donor plasma and recombinant SARS-CoV-2 S-proteinand receptor-binding domain (RBD) proteins were tested using pseudo-virus (PSV) neutralization methodsfound that the binding price of donor plasma and SARS-CoV-2 S protein varied greatly, but the effect price of RBD was reduced by an order of magnitudeSARS-CoV-2 neutralizing antibody separation strategy, the researchers identified monoclonal antibodies (mAb) on eight of the donors, cloned and expressed 2045 antibodies, and tested their binding to RBD and S proteins, as well as the neutralizing of SARS-CoV-2 PSV assaysresults were unexpected, and the viral infection responded more strongly to the non-RBD regions of the S protein, but only a small portion was neutralizedIn contrast, RBD binds fewer antibodies, but neutralises a higher proportion of SARS-CoV-2 pseudo-virusesTHE SARS-CoV antigen binding and neutralized antibody isolation and functional screening, the researchers used the S protein and THE RBD protein as antibodies to capture antigen detection binding to non-competitive sites, and found three antigen decision cluster boxes (RBD-A, RBD-B and RBD-C) and S proteins of the three antigen decision cluster boxes (SA, SB and SC), they continued to evaluate the neutrality of monoclonal antibodies against SARS-CoV-2 and SARS-CoV-1 counterfeit virusesThe results showed that the most effective neutralizing antibodies were antibodies against RBD-A epitopes, including two antibodies CC6.29 and CC6.30, which were efficient in neutralizing SARS-CoV-2 pseudoviruses, while CC6.33 was for RBD-B, which neutralized both SARS-CoV-2 and SARS-CoV-1through cell surface competitive experiments and surface plasma resonance (SPR) experiments, the researchers determined that the epitope RBD-A is the preferred target for neutralizing antibodies, and that the corresponding increase in the affinity of mAb and RBD-A may lead to a corresponding increase in neutrality forceIt is worth noting that all three antibodies can neutralise the now mutated SARS-CoV-2 virusSARS-CoV-2-specific neutralized monoantithed protection weight loss and pulmonary virus replication in Syrian hamsters
In order to study the protection of in vitro neutralizing antibodies against SARS-CoV-2 in the body, the researchers screened out two mAbs to treat Syrian hamster animal models The hamster was weighed as a measure of disease caused by infection using the non-existing antibody Den3 of the dengue virus as a control results showed that in CC12.1 and targeted RBD-A epitope treatment, the control group lost an average weight of 13.6%, while the experimental group receiving neutral RBD-A antibodies at a dose of 2 mg or 500 mg was not weight loss, and the lung virus load was further verified by using real-time PCR to determine its lung virus load The researchers measured the serum concentration of antibodies before the Attack of the Syrian hamster nasal virus and found that the antibody serum concentration was about 22 ?g/ml of nAb, which was sufficient to reduce the disease caused by a 50% weight loss at a serum concentration of 12 ?g/ml However, the concentration of effective antibodies required to prevent disease at the site of infection has yet to be determined summary, the study showed that nAb plays a role in the prevention and potential treatment of COVID-19 At the same time, nAb also defines protective tables that can be used to guide vaccine design notable, in addition to the study, Science published four other studies on the same day on antibodies to the new coronavirus, including human-sourceed antibodies and antibody "cocktail therapy." Previously, the results of neutralizing antibodies in the new coronavirus have also been frequently published We look forward to these findings as soon as possible to promote clinical application development and provide a strong medical intervention for the treatment and prevention of new coronary pneumonia References: of the Isolation of the potent SARS-CoV-2 neutralizing antibodies and protection from disease in a small animal model.