HUMAN IgM ANTI-SARS-COV-2 SPIKE (S1) RBD ANTIBODY (DH6)

Recombinant humanized IgM version of the neutralizing mouse monoclonal antibody MAB12444. Antibody is specific for SARS-CoV-2 receptor binding domain (RBD).

PRODUCT DETAILS – HUMAN IgM ANTI-SARS-COV-2 SPIKE (S1) RBD ANTIBODY (DH6)

• Recombinant humanized IgM antibody, which is specific for SARS-CoV-2 RBD.
• The original monoclonal antibody (MAB12444) is specific for the spike receptor binding domain of SARS-CoV-2, recognizing RBD from Wuhan-Hu-1, UK (Alpha), South African (Beta) Brazilian (Gamma) and Indian Kerala variants. No cross-reactivity observed in ELISA with SARS-CoV-2 subunit 2 (S2) or spike subunit 1 (S1) proteins from SARS-CoV, MERS-CoV, HCoV-NL63, HCoV-OC43, HCoV-229E and HCoV-HKU1.
• The original monoclonal antibody (MAB12444) is neutralizing against SARS-CoV-2, but not against SARS-CoV-1 or MERS-CoV.
• The original monoclonal antibody (MAB12444) is suitable for use as capture or detection antibody in ELISA assays.
• Immunogen was SARS-CoV-2 RBD (REC31882, aa 1-223) expressed in HEK293 cells.

BACKGROUND

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the coronavirus induced disease 19 (COVID-19) which emerged in China in late 2019, resulting in a worldwide epidemic (Zhou et al., 2020). SARS-CoV-2 is an enveloped positive-sense single-stranded RNA virus with a number of important structural proteins, including the envelope (E) protein, the membrane (M) protein, the spike (S) protein, and the nucleoprotein (N). The S protein assists in the attachment of the virus to the human cell and comprises intracellular, transmembrane, and extracellular regions. The extracellular region contains the S1 receptor binding subunit (RBD) and the S2 membrane fusion subunit. Generally, following SARS-CoV-2 infection, antibodies appear after 7–14 days and persist for weeks after viral clearance. The most commonly detected antibodies are against the N protein and the S protein. Coronavirus neutralizing antibodies primarily target the trimeric spike (S) glycoproteins on the viral surface (Wang et al., 2020) and can change the course of infection in an infected individual by supporting virus clearance or protecting an uninfected host that is exposed to the virus (Prabakaran et al., 2009). However, the antibody responses against SARS-CoV-2 remain poorly understood (Tang et al., 2020) and better understanding of how the viral coating triggers a healthy immune system’s recognition and neutralisation of the virus is critical for optimisation of diagnostic tests (Petherick, 2020). It has been suggested that spike RBD may be a better target than N for diagnostic tests (Rosadas et al., 2020). The Native Antigens monoclonal antibodies, which are specific for SARS-CoV-2, have been manufactured to meet the need for improved COVID-19 diagnostic assays.

REFERENCES

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