SARS-CoV-2 invades host cells via a novel route: CD147-spike protein

in vitro antiviral tests indicated Meplazumab, an anti-CD147 humanized antibody, significantly inhibited the viruses from invading host cells, with an EC 50 of 24.86 μg/mL and IC 50 of 15.16 μg/mL. Second, we validated the interaction between CD147 and SP, with an affinity constant of 1.85×10 -7 M. Co-Immunoprecipitation and ELISA also confirmed the binding of the two proteins. Finally, the localization of CD147 and SP was observed in SARS-CoV-2 infected Vero E6 cells by immuno-electron microscope. Therefore, the discovery of the new route CD147-SP for SARS-CoV-2 invading host cells provides a critical target for development of specific antiviral drugs. The images were developed after incubation with the secondary antibodies (goat anti-mouse IgG(H+L) goat anti-rabbit IgG(H+L) antibody; at room for 1 hour. ELISA assay was performed to identify the interaction of CD147 and SP. The His-SP (RBD) protein was coated on microplate, and then incubated with different concentrations of His-CD147 protein (2-fold dilution, 400-0.195 μg/mL) at 37°C for 1 hour. After washing with PBST, the samples were incubated with anti-CD147 antibody (HAb18, produced by our laboratory) for 1 hour; and then incubated with horseradish peroxidase (HRP)-labeled goat anti-mouse antibody for 1 hour. After coloration, the OD value at 450 nm was measured with a full-wavelength microplate reader (Epoch, BioTek Instruments, Inc.). The ability of Meplazumab to compete with SP for CD147 binding was performed by competitive inhibition ELISA. The protein His-CD147 was coated onto the wells of microplate, the mixture of His-SP (RBD) and Meplazumab ( 2-fold dilution, 200-0.781 µg/mL) was added and incubated. Subsequently, the samples were incubated with anti-SARS-CoV-2 Spike antibody (40150-R007, Sino Biological, China) and then detected with HRP-labeled goat anti-rabbit antibody for 1 hour at 37°C, the following to