Update: December 01, 2021
Anti-SARS-CoV-2 nucleoprotein antibodies
Anti-SARS-CoV-2 nucleoprotein antibodies (Cat.# 5-CVnp, MAbs C518, C524, C527, C706, C715) bind to the N-terminal part of the nucleoprotein: N47-A173. Several mutations found in circulating SARS-CoV-2 variants are located outside of this region however. Thus, it is important to test all relevant and concerning mutations regardless of their location.
The prevalence of nucleoprotein mutations changes over time. For up-to-date information, see: https://outbreak.info/compare-lineages.
Anti-SARS-CoV-2 nucleoprotein antibodies and the omicron variant
It is expected that all our key antibodies (cat. #5-CVnp) recognize the omicron variant. Mutations P13L, Δ31-33, R203K, G204R can be found in nucleoprotein. All our N-terminal antibodies including C524, C706, C518, C527 and C715 bind to N47-A173 region of the nucleoprotein so mutations are outside of this region.
Compiled information regarding different variants and mutations is shown below. This information is updated regularly. Variants were screened using recombinant antigens, as well as feedback from end-users that have tested selected antibody pairs with live virus variant strains.
Mutations/ Variants/
P13L, Delta31-33, R203K/ Omicron (B.1.1529)
>Mutations located in nucleoprotein are outside the epitope of our key antibodies, incl. C524, C706, C518, C527 and C715. Our antibodies recognize the omicron variant.
Mutations/ Variants/
D3L, R203K / G204R/S235F/ Alpha (B.1.1.7) S
>MAb pairs C524-C706, C518-C706, C715-C706 (cat. #5-CVnp) and pAb (cat. #6-CVnp). See Figure 1 for performance of selected pairs confirmed with patient samples/live virus variants: C524-C706, C518-C706, C715-C706.
Mutations/ Variants/
T205I/ Beta (B.1.351);Epsilon (B.1.427 and B.1.429)
>See Table 1 and Figure 1.
Mutations/ Variants/
P80R, R203K,G204R/ Gamma (P.1)/
>Two of three mutations are the same as in the Alpha variant. P80R mutation. Performance confirmed with live virus variant for C715-C706.
Mutations/ Variants/
D63G, R203M, D377Y/ Delta (B.1.617.2)/
>D63G: see Figure 1. Two other mutations are located outside the epitope of our key monoclonal antibodies.
Mutations/ Variants/
R203M, D377Y/ Kappa (B1617.1)
>Mutations located outside epitope of our key monoclonal antibodies.
Important: To minimize the likelihood that a COVID-19 antigen test will fail to recognize emerging variants, we recommend using more than two antibodies per assay.
Table 1. Detection of SARS-CoV-2 virus variants tested with two recommended pair combinations on lateral flow. Swab samples were used as specimen. Note that line intensity depends on virus load that can vary between samples. The results show that these two pairs detect all three virus variants in lateral flow.
Figure 1. Specificity of anti-SC-NP MAbs sandwich antibody pairs to different point mutations. Signal from recombinant wild type NP (Cat.# 8COV3) was considered as 100%.
While all 1+1 (capture-detection) pair combinations tested are able to detect the key variants currently circulating in the world, we recommend using more than two MAbs in a COVID-19 Antigen test. This will increase the likelihood of the test to efficiently recognize future variants.
Anti-Spike RBD Antibodies
The Alpha variant has deletions and mutations within the spike protein, one of which is within the RBD part of the protein (N501Y). We have confirmed that all our anti-RBD MAbs detect the N501Y variant (recombinant antigen) similarly to the wild type virus.
The Beta variant bears four mutations in its spike protein (K417N, E484K, N501Y, D614G). Our anti-Spike MAbs recognize recombinant variant spike protein similarly to wild type virus.
The Gamma variant contains three mutations in its spike protein (K417N, E484K, N501Y). Same mutations are found in the South African variant. Based on results with the South African variant protein, it is expected that our anti-RBD antibodies recognize the Brazilian variant similarly to the wild type.
Figure 3. Detection of the Beta variant spike (recombinant antigen) with Anti-RBD antibodies. Signal from recombinant wild type RBD (Cat.# 8COV1) considered 100%.
Learn more:
Cat. #5-CVnp. Monoclonal Anti-SARS-CoV-2, Nucleoprotein
Cat. #6-CVnp. Polyclonal Anti-SARS-CoV-2 Nucleoprotein
Cat. #8-CoVnp. SARS-CoV-2, Nucleoprotein, recombinant
Cat. #5-CVs. Monoclonal Anti-SARS-CoV-2, Spike
Cat. #8-CoVrbd. SARS-CoV-2 Spike RBD, mammalian recombinant
Browse our products/Order online: AdvImmuno.com
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