SARS-CoV-2 Neutralizing Antibodies

The ongoing COVID-19 pandemic has changed the world in a way that hasn't been seen in generations. Since this January, over 18.4M people have contracted the deadly disease, and more than 699,000 lives have been claimed worldwide. The medical research community is exploring every avenue to find solutions for the prevention, detection, and treatment of the disease.

Neutralizing antibodies are of specific interest to scientists, as they can efficiently stop the infection by blocking the interaction between the SARS-CoV-2 virus and the host cells. Most neutralizing antibodies react to the receptor binding domain (RBD) of the spike protein, which directly binds with the cell surface receptor ACE2.


Sino Biological has developed three neutralizing antibodies against SARS-CoV-2. The activities of these antibodies have been extensively validated in both binding assays, and pseudovirus infection assays. These reagents can be used as reference antibodies in neutralization assays, and possibly animal studies as well.

SARS-CoV-2 Neutrazling Antibodies   All SARS-CoV-2 Antibodies   All SARS-CoV-2 Antigens

Specific and Neutralizing Antibodies against SARS-CoV-2 Spike

Anti-SARS-CoV-2 S1 Neutralizing Antibody, Mouse MAb (Catalog# 40591-MM43)

Anti-SARS-CoV-2 RBD Neutralizing Antibody, Mouse MAb (Catalog# 40592-MM57)

Anti-SARS-CoV-2 RBD Neutralizing Antibody, Rabbit MAb (Catalog# 40592-R001)

Neutralization Activity Assay
(Measured by microneutralization assay in vitro)
The microneutralization assay was performed on 293T-ACE2 cells infected with SARS-CoV-2 Spike PSV under the treatment of serial dilutions of neutralizing antibodies. Neutralizing antibodies can effectively inhibit the infection of SARS-CoV-2 Spike pseudovirus on ACE2 overexpression 293T cells.
S1 Neutralizing Antibody
Conc. (µg/mL) Inhibition%
100 96.39%
10 94.57%
1 42.24%
0.1 -5.53%
The IC50 is typically 1.41 µg/mL.
RBD Neutralizing Antibody
Conc. (µg/mL) Inhibition%
100 95.51%
10 93.32%
1 75.69%
0.1 10.11%
The IC50 is typically 0.41 µg/mL.
RBD Neutralizing Antibody
Conc. (µg/mL) Inhibition%
100 99.56%
4 99.9%
0.16 59.29%
0.032 5.59%
The IC50 is typically 0.11 µg/mL.
Competitive-ELISA Assay
(Measured by Inhibitor Screening ELISA Kit )
Neutralizing ability was detected by SARS-CoV-2 Inhibitor Screening ELISA Kit (Catalog# KIT001) using competitive ELISA.
S1 Neutralizing Antibody
Mouse MAb

The IC50 is typically 0.857 nM
RBD Neutralizing Antibody
Mouse MAb

The IC50 is typically 3.694 nM
RBD Neutralizing Antibody
Rabbit MAb

The IC50 is typically 0.066 nM
Specificity Assay
SARS-CoV-2 shares an 80% sequence identity to the 2003 SARS-CoV. Hence, antibodies raised against SARS-CoV-2 antigens often shows a various degree of cross-reactivity with the corresponding antigens of 2003 SARS-CoV. The similarities between SARS-CoV-2 and other members of human coronavirus are very limited. These two neutralizing antibodies are specific to the SARS-CoV-2 which have no cross-reactivity with other 6 Human coronaviruses.
S1 Neutralizing Antibody
RBD Neutralizing Antibody
ELISA-(cross) reactivity was assessed of all 7 kinds of human coronavirus Spike S1 and RBD protein, including SARS-CoV-2, SARS-CoV, MERS-CoV, HCoV-HKU1, HCoV-229E, HCoV-OC43, HCoV-NL65. These two SARS-CoV-2 antibodies are specific to SARS-CoV-2 spike antigen, other human coronaviruses displayed no ELISA-cross-reactivity with them(OD450 in grey).
Affinity Assay
The binding between immobilized SARS-CoV-2 RBD protein (40592-V08B-B) and the anti-Spike antibody 40592-R001 in Octet RED assay.
Recombinant Antibody Production