Figure 1. Design and characterization of 5 IAs.
(A, B) Schematic diagrams show the structures of IAs, which are scFv-hIgG-Fc–like molecules bearing antibody-binding domains to gp120 or human CD4. scFv, single-chain variable fragment; hIgG, human immunoglobulin G, VH, variable heavy chain; VL, variable light chain; CH, constant heavy chain. (C) The released IAs in culture supernatants were detected by Western blot analysis under reducing conditions. (D) Each IA displayed neutralizing activity against pseudovirus HIV-1ADA. (E) Paired IAs were tested for synergistic effects in a checkerboard neutralization assay. The synergy volumes of –50 to 50, 50 to 100, and >100 in a synergy plot at the 95% CI were used to define additive, slight synergistic, and synergistic effects, respectively. Data represent mean ± SD with duplicates. All experiments were repeated at least twice.