Fig. 3.

Potential mechanisms explaining the increased resistance of cell-associated HIV-1 to bNAbs-mediated neutralization. a bNAbs may poorly access virions present at the VS because of the physical proximity of donor and target cell membranes. b VS-mediated HIV-1 is associated with high MOIs. c Viruses budding at the VS may incorporate cellular proteins differently than cell-free virions, possibly leading to different susceptibilities to bNAbs. d Env conformation and stability of Env-bNAb complexes at the cell surface. Env conformation may be different at the surface of cell-free virus and at the plasma membrane. The stability of Env-bNAb complexes at the cell surface depends on the antibody and the viral strain. Donor cells are in brown and uninfected cells in blue