Antibody affinity maturation using yeast display with detergent-solubilized membrane proteins as antigen sources

Protein Eng Des Sel. 2013 Feb;26(2):101-12. doi: 10.1093/protein/gzs077. Epub 2012 Oct 28.

Abstract

Antigen preparations in the form of detergent-solubilized cell lysates could, in principle, render membrane proteins (MPs) compatible with in vitro antibody engineering technologies. To this end, detergent-solubilized cell lysates were coupled with the yeast surface display platform to affinity mature an anti-transferrin receptor (TfR) single-chain antibody (scFv). Lysates were generated from TfR-expressing HEK293 cells by solubilization with detergent-containing buffer after undergoing plasma membrane-restricted biotinylation. Lysate-resident TfR was then combined with a mutagenic anti-TfR scFv library in a competitive, dissociation rate screen, and scFvs were identified with up to 4-fold improved dissociation rates on the surface of yeast. Importantly, although the lysates contained a complex mixture of biotinylated proteins, the engineered scFvs retained their TfR binding specificity. When secreted by yeast as soluble proteins, mutant scFvs bound to cell surface TfR with 3-7-fold improvements in equilibrium binding affinity. Although a known MP antigen was targeted for purposes of this study, employing biotin tagging as a means of antigen detection makes the lysate-based approach particularly flexible. We have previously shown that yeast display can be used to identify lead antibodies using cell lysate-resident MP antigens, and combined with this work showing that antibodies can also be quantitatively engineered using cell lysates, these approaches may provide a high-throughput platform for generation and optimization of antibodies against MPs.

Publication types

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

MeSH terms

  • Antibody Affinity
  • Antibody Specificity
  • Antigens / immunology*
  • Cell Extracts
  • Cell Surface Display Techniques*
  • Detergents / chemistry
  • Directed Molecular Evolution
  • HEK293 Cells
  • Humans
  • Membrane Proteins / immunology
  • Octoxynol / chemistry
  • Peptide Library
  • Protein Binding
  • Protein Engineering
  • Receptors, Transferrin / immunology*
  • Saccharomyces cerevisiae*
  • Single-Chain Antibodies / biosynthesis*
  • Single-Chain Antibodies / genetics
  • Solubility

Substances

  • Antigens
  • Cell Extracts
  • Detergents
  • Membrane Proteins
  • Peptide Library
  • Receptors, Transferrin
  • Single-Chain Antibodies
  • Octoxynol