Abstract
COVID-19 pneumonia is spreading widely in the world now. Currently, no specific antiviral drugs have been developed. The vaccine is the most effective way to control the epidemic. Passive immune antibodies are also an effective method to prevent and cure COVID-19 pneumonia. We used SARS-CoV-2 S-RBD as an antigen to immunize layers in order to extract, separate and purify SARS-CoV-2-IgY from egg yolk. SARS-CoV-2-IgY(S-IgY) can block the entry of SARS-CoV-2 into the Cells and reduce the viral load in cells. The EC50 of W3-IgY (S-IgY in the third week after immunization) is1.35 ± 0.15nM. The EC50 of W9-IgY (S-IgYin the ninth week after immunization) is 2.76 ± 1.54 nM. When the dose of S-IgY is 55 nM, the fluorescence representing intracellular viral protein is obviously weakenedin Immunofluorescence microscopy.
Results of Sars-CoV-2 /VeroE6 cell experiment confirmed that S-IgY had strong antiviral effecton SARS-Co-V-2, and its EC50 is 27.78 ± 1.54nM vs 3259 ± 159.62 nM of Redesivir (differ>106 times, P<0.001).
S-IgY can inhibit the entry and replication of SARS-CoV-2, which is related to its targeting the ACE2 binding domain.
S-IgY is safe, efficient, stable and easy to obtain. This antibody may have the potential to be an effective method for the prevention and treatment of COVID-19 pneumonia.
Graphical Abstract (see Fig.1.)
Competing Interest Statement
The authors have declared no competing interest.