Structure-based design of hepatitis C virus E2 glycoprotein improves serum binding and cross-neutralization

Brian G. Pierce; Zhen-Yong Keck; Ruixue Wang; Patrick Lau; Kyle Garagusi; Khadija Elkholy; Eric A. Toth; Richard A. Urbanowicz; Johnathan D. Guest; Pragati Agnihotri; Melissa C. Kerzic; Alexander Marin; Alexander K. Andrianov; Jonathan K. Ball; Roy A. Mariuzza; Thomas R. Fuerst; Steven K.H. Foung

We utilized two approaches to design variants of the E2 glycoprotein to improve its antigenicity and immunogenicity (Figure 1) . For one approach, we used the previously reported structure of the affinity matured bnAb HC84.26.5D bound to its epitope from E2 antigenic domain D (31) (PDB code 4Z0X), which shows the same epitope conformation observed in the context of other domain D human monoclonal antibodies (HMAbs) targeting this site (32). Analysis of this epitope structure for potential proline residue substitutions to stabilize its HMAb-bound conformation identified several candidate sites ( Figure 1A, Table 1 ). We selected one of these substitutions, H445P, that is adjacent to core contact residues for domain D located at aa 442-443 (32) for subsequent experimental characterization, due to its position in a region with no secondary structure, and location between residues Y443 and K446 which both make key antibody contacts author/funder. All rights reserved. No reuse allowed without permission.