LY-CoV2-derived Anti-SARS-CoV-2 RBD monoclonal antibodies

Specific SARS-CoV-2 Spike-RBD recombinant human IgG1 & mouse IgG2a antibodies

SARS-CoV-2 specific neutralization by Bamlinivimab & Etesevimab

Antibody description

InvivoGen provides a set of recombinant monoclonal antibodies (mAbs) featuring either a human IgG1 or a mouse IgG2a constant region, and the variable region of 'Bamlanivimab (LY-CoV555)' or 'Etesevimab (LY-CoV016'),  two clones originally described as potent  SARS-CoV-2 neutralizing mAbs [1,2]:

— Anti-CoV2RBD-bam-hIgG1 and Anti-CoV2RBD-bam-mIgG2a (derived from Bamlavinimab)

— Anti-CoV2RBD-ete-hIgG1 and Anti-CoV2RBD-ete-mIgG2a (derived from Etesevimab)

InvivoGen's Anti-CoV2RBD-bam and Anti-CoV2RBD-ete mAbs have been generated by recombinant DNA technology, produced in CHO cells, and purified by affinity chromatography, ensuring lot-to-lot reproducibility. Furthermore, these mAbs have been functionally validated by ELISA (see data below). The absence of bacterial contamination has been confirmed by cellular assays.

➔ These antibodies have been functionally validated by ELISA and FACS on SARS-CoV2 Spike variants.

Background

Bamlavinimab and Etesevimab (originally named 'clone CB6') were generated using serum from a convalescent patient [1, 2]. These mAbs specifically target two distinct but overlapping regions of the SARS-CoV-2 S-RBD and potently block its binding to the ACE2 receptor on target cells [1, 2]. 

More details on Bamlavinimab and Etesevimab

Applications

• Detecting the presence of SARS-CoV-2 in culture supernatant and/or in serum (ELISA)
• Flow cytometry binding assays 
• Developing neutralizing antibody cocktails against SARS-CoV-2
• Monitoring SARS-CoV-2 variant escape

Quality control

• Functionally validated by ELISA using Spike-RBD proteins derived from SARS-CoV-2 variants and either HRP or Luciferase detection

References

1. Jones B.E. et al., 2021. The neutralizing antibody, LY-CoV555, protects against SARS-CoV-2 infection in nonhuman primates. Sci Transl Med 13(593), eabf1906(2021).
2. Shi R. et al., 2020. A human neutralizing antibody targets the receptor-binding site of SARS-CoV-2. Nature. 584:120-124.

Figures

SARS-CoV-2 Spike-RBD proteins (3 μg/ml) derived from the Wuhan (A), United Kingdom (U.K.) (B), or South-Africa (S.A.) (C) variants were coated on ELISA plates overnight. A 3-fold serial dilution of Anti-CoV2RBD-bam-IgG2a (red curve), Anti-CoV2RBD-ete-mIgG2a (orange curve), CR3022-derived Anti-Spike-RBD mIgG2a (back curve), of Anti-βGal-mIgG2a antibodies (grey curve) was performed for the capture step. A HRP-labelled Anti-mIgG2a antibody (1/1000 dilution) and the HRP substrate OPD (o-phenylenediamine dihydrochloride) were used for the detection step. Absorbance was read at 490 nm.

Anti-human or Anti-murine IgG F(ab’)2 fragment (2 μg/ml) was coated on an ELISA plate overnight. Anti-CoV2RBD-bam-hIgG1 or -mIgG2a (A), Anti-CoV2RBD-ete-hIgG1 or -mIgG2a (B) along with RBD-Lucia proteins (original, V2 and V4; 1 μg/ml) were added and incubated for 2 hours at room temperature. After washing (3x times), binding affinity was assessed by measuring the activity of Lucia luciferase in the supernatant using QUANTI-Luc™. Data are shown as a fold change over no antibody.

Specifications

Specificity: SARS-CoV-2 Spike RBD
Clonality: Monoclonal
Isotypes: hIgG1 or mIgG2a
Source: CHO cells
Formulation: 0.2 μm filtered solution in a sodium phosphate buffer with glycine, saccharose, and stabilizing agents.
Purification: purified by affinity chromatography with protein G (hIgG1) or protein A (mIgG2a)
Quality control:

• The complete sequence of each antibody construct has been verified.
• Antibody binding has been validated by ELISA using Spike-RBD proteins derived from SARS-CoV-2 variants and either HRP or Luciferase detection.
• The absence of bacterial contamination (e.g. lipoproteins and endotoxins) has been confirmed using HEK-Blue™ TLR2 and HEK-Blue™ TLR4 cellular assays.

Contents

Note: Each antibody is sold separately.

Details

Bamlavinimab and Etesevimab (originally named 'clone CB6') were generated using serum from a convalescent patient [1, 2]. These mAbs specifically target two distinct but overlapping regions of the SARS-CoV-2 S-RBD and potently block its binding to the ACE2 receptor on target cells [1, 2]. Prophylactic administration of Bamlavinimab protects against SARS-CoV-2 infection in non-human primates [1]. Treatment using Bamlavinimab has been authorized under emergency use for COVID-19 outpatients [3, 4]. In addition, a clinical trial (NCT04427501) is investigating the efficacy of Bamlavinimab and Etesevimab combination.

Learn more about the SARS-CoV-2 Spike protein.

References

1. Jones B.E. et al., 2021. The neutralizing antibody, LY-CoV555, protects against SARS-CoV-2 infection in nonhuman primates. Sci Transl Med 13(593), eabf1906(2021).
2. Shi R. et al., 2020. A human neutralizing antibody targets the receptor-binding site of SARS-CoV-2. Nature. 584:120-124.
3. Chen P. et al., 2020. SARS-CoV-2 Neutralizing Antibody LY-CoV555 in Outpatients with Covid-19. N Engl J Med. 384(3):229-237.
4. https://www.fda.gov/media/145610/download.