title: Rapid conformational epitope mapping of anti-gp120 antibodies with a designed mutant panel displayed on yeast.
abstract: gp120 is a substrate for protein engineering both for human immunodeficiency virus (HIV) immunogen design and as a bait for isolating anti-HIV antibodies from patient samples. In this work, we describe the display of a stripped core gp120 on the yeast cell surface. Validation against a panel of neutralizing antibodies confirms that yeast-displayed gp120 presents the CD4 binding site in the correct conformation. We map the epitope of the broadly neutralizing anti-gp120 antibody VRC01 using both a random mutagenesis library and a defined mutant panel and find that the resultant epitope maps are consistent with one another and with the crystallographically identified contact residues. Mapping the VRC01-competitive antibodies b12 and b13 reveals energetic differences in their epitopes that are not obvious from existing crystal structures. These data suggest mutation sets that abrogate binding to broadly neutralizing antibodies with greater specificity than the canonical mutation D368R, useful in rapidly assessing the nature of a vaccine response.
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Jordi
authors.initials: J
authors.lastname: Mata-Fink
authors.forename: Barry
authors.initials: B
authors.lastname: Kriegsman
authors.forename: Hui Xin
authors.initials: HX
authors.lastname: Yu
authors.forename: Hanna
authors.initials: H
authors.lastname: Zhu
authors.forename: Melissa C
authors.initials: MC
authors.lastname: Hanson
authors.forename: Darrell J
authors.initials: DJ
authors.lastname: Irvine
authors.forename: K Dane
authors.initials: KD
authors.lastname: Wittrup
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D057134:Antibodies, Neutralizing / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D015704:CD4 Antigens / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D015195:Drug Design; D018604:Epitope Mapping; D000939:Epitopes / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D005434:Flow Cytometry; D015483:HIV Antibodies / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D015699:HIV Envelope Protein gp120 / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D016296:Mutagenesis; D050505:Mutant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019151:Peptide Library; D011487:Protein Conformation; D015202:Protein Engineering; D012441:Saccharomyces cerevisiae / Q000276:immunology* / Q000378:metabolism
chemical_list: D000888:Antibodies, Anti-Idiotypic; D057134:Antibodies, Neutralizing; D015704:CD4 Antigens; D000939:Epitopes; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; D050505:Mutant Proteins; D019151:Peptide Library