Double and Triple Combinations of Broadly Neutralizing Antibodies Provide Efficient Neutralization of All HIV-1 Strains from the Global Panel

Abstract

The use of broadly neutralizing antibodies (bNAbs) is a promising approach to HIV-1 treatment. In this work, we evaluate the neutralizing activity of the following HIV-1 bNAbs: VCR07-523, N6, PGDM1400, CAP256-VRC26.25, 10-1074, PGT128, 10E8, and DH511.11P, which are directed to different Env surface epitopes. We used the global panel of HIV-1 pseudoviruses to analyze the bNAbs' potency and chose the most potent ones. To achieve maximum neutralization breadth and minimum IC₅₀ concentration, the most effective antibodies were tested in double and triple combinations. Among the doubles, the combinations of N6+PGDM1400 and N6+PGT128 with IC₅₀ ≤ 0.3 µg/mL proved to be the most effective. The most effective triple combination was N6+PGDM1400+PGT128. Our data demonstrate that this combination neutralizes pseudoviruses of the global HIV-1 panel with IC₅₀ ≤ 0.11 µg/mL and IC₈₀ ≤ 0.25 µg/mL.

Keywords: 10-1074; 10E8; CAP256-VRC26.25; DH511.11P; Env; HIV-1; HIV-1 global panel; N6; PGDM1400; PGT128; VCR07-523; broadly neutralizing antibodies.

Figure A1

Schematic representation of expression cassettes encoding the heavy and light chains of antibodies: CMV, cytomegalovirus promoter; Kozak, Kozak sequence; HGH signal LC/HC, signal peptide; VH/VL, variable domain of heavy/light chain; CH/CL, constant domain of heavy/light chain; PolyA, SV40 polyadenylation signal.

Figure A2

Pseudoviruses neutralization curves for bNAbs (A–H) (n = 2, ±SEM, on the Y-scale, 100% means no neutralization and 0%—complete neutralization).

Figure A2

Pseudoviruses neutralization curves for bNAbs (A–H) (n = 2, ±SEM, on the Y-scale, 100% means no neutralization and 0%—complete neutralization).

Figure A2

Pseudoviruses neutralization curves for bNAbs (A–H) (n = 2, ±SEM, on the Y-scale, 100% means no neutralization and 0%—complete neutralization).

Figure A2

Pseudoviruses neutralization curves for bNAbs (A–H) (n = 2, ±SEM, on the Y-scale, 100% means no neutralization and 0%—complete neutralization).

Figure A2

Pseudoviruses neutralization curves for bNAbs (A–H) (n = 2, ±SEM, on the Y-scale, 100% means no neutralization and 0%—complete neutralization).

Figure 1

Schematic representation of glycoprotein Env homotrimer on the viral membrane. Each monomer consists of noncovalently bound gp120 and gp41 polyproteins. Epitopes for bNAbs are depicted in different colors. bNAbs used in this work are listed in frames.

Figure 2

Antibody concentration (ELISA, total human IgG) (n = 3, ±SEM).

Figure 3

Western blot analysis of broadly neutralizing antibodies under reducing conditions.

Figure 4

Pseudoviruses neutralization curves for bNAbs combinations (n = 2, ±SEM, on the Y-scale, 100% means no neutralization and 0%—complete neutralization).