Selection, identification, and characterization of SARS-CoV-2 monoclonal antibody resistant mutants

J Virol Methods. 2021 Apr;290:114084. doi: 10.1016/j.jviromet.2021.114084. Epub 2021 Jan 26.


The use of monoclonal neutralizing antibodies (mNAbs) is being actively pursued as a viable intervention for the treatment of Severe Acute Respiratory Syndrome CoV-2 (SARS-CoV-2) infection and associated coronavirus disease 2019 (COVID-19). While highly potent mNAbs have great therapeutic potential, the ability of the virus to mutate and escape recognition and neutralization of mNAbs represents a potential problem in their use for the therapeutic management of SARS-CoV-2. Studies investigating natural or mNAb-induced antigenic variability in the receptor binding domain (RBD) of SARS-CoV-2 Spike (S) glycoprotein, and their effects on viral fitness are still rudimentary. In this manuscript we described experimental approaches for the selection, identification, and characterization of SARS-CoV-2 monoclonal antibody resistant mutants (MARMs) in cultured cells. The ability to study SARS-CoV-2 antigenic drift under selective immune pressure by mNAbs is important for the optimal implementation of mNAbs for the therapeutic management of COVID-19. This will help to identify essential amino acid residues in the viral S glycoprotein required for mNAb-mediated inhibition of viral infection, to predict potential natural drift variants that could emerge upon implementation of therapeutic mNAbs, as well as vaccine prophylactic treatments for SARS-CoV-2 infection. Additionally, it will also enable the assessment of MARM viral fitness and its potential to induce severe infection and associated COVID-19 disease.

Keywords: COVID-19; Monoclonal antibodies; Monoclonal antibody resistant mutant; Neutralizing antibodies; RBD; SARS-CoV-2; Spike glycoprotein; Viral drift.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibodies, Monoclonal / pharmacology*
  • Antibodies, Monoclonal / therapeutic use
  • Antibodies, Neutralizing / immunology
  • Antibodies, Neutralizing / pharmacology
  • Antibodies, Neutralizing / therapeutic use
  • Antigenic Variation / genetics*
  • Binding Sites / genetics
  • Binding Sites / immunology
  • COVID-19 / drug therapy
  • COVID-19 / virology
  • Chlorocebus aethiops
  • Drug Resistance, Viral / genetics*
  • Humans
  • Phenotype
  • SARS-CoV-2 / drug effects
  • SARS-CoV-2 / genetics*
  • SARS-CoV-2 / immunology
  • Selection, Genetic*
  • Spike Glycoprotein, Coronavirus / genetics
  • Spike Glycoprotein, Coronavirus / immunology
  • Vero Cells


  • Antibodies, Monoclonal
  • Antibodies, Neutralizing
  • Spike Glycoprotein, Coronavirus
  • spike protein, SARS-CoV-2