The need for high-affinity, SARS-CoV-2-specific monoclonal antibodies (mAbs) is crucial in the face of the global COVID-19 pandemic, as such reagents can have important diagnostic, research and therapeutic applications. Researchers at the CDC and the Georgia Institute of Technology have developed an accelerated immunization (using three different immunogens) and hybridoma screening strategy to create novel, SARS-CoV-2-specific mouse mAbs. Several of these purified mouse mAbs with neutralizing properties are available to encourage the development of immunoassays that are broadly reactive to key SARS-CoV-2 variants.

The receptor binding domain (RBD) within the S1 subunit of the S glycoprotein has shown the greatest interest due to its key interaction with the human angiotensin converting enzyme 2 (hACE2) receptor found on many cell types, in particular lung epithelial cells.¹ Differing functions, including binding of diverse protein epitopes, virus neutralization, impact on RBD-hACE2 binding, and immunohistochemical staining of infected lung tissue, were all correlated with variable gene usage and sequence to develop this set of mAbs. Variations in binding to key S mutations of interest and neutralization of variants reported for these novel mAbs offer functional utility in Western blot and ELISA assays.¹

References:

1. Chapman, A. P., et al. “Rapid Development of Neutralizing and Diagnostic SARS-COV-2 Mouse Monoclonal Antibodies.” Sci. Rep. 11 (2021): 9682. PubMed: 33958613.

Image:  Colorized scanning electron micrograph of partially lysed cells infected with SARS-CoV-2 (NIAID/CC BY 2.0)